What's Your Ecotype?

Three More Recent Papers on Red Knot Migration

noreply@blogger.com (Ian Parnell) — Sat, 30 Jun 2012 05:59:00 +0000

Three more recent papers on Red Knot migration . . . I'll provide summaries later.

ScienceDirect - Emotion, Space and Society : Tangled up in knots: An emotional ecology of field science: Tangled up in knots: An emotional ecology of field science

BioOne Online Journals - Sufficiency of Horseshoe Crab Eggs for Red Knots During Spring Migration Stopover in Delaware Bay USA: "Sufficiency of Horseshoe Crab Eggs for Red Knots During Spring Migration Stopover in Delaware Bay USA"

BioOne Online Journals - Migration and Over-Wintering of Red Knots (Calidris canutus rufa) along the Atlantic Coast of the United States: Migration and Over-Wintering of Red Knots (Calidris canutus rufa) along the Atlantic Coast of the United States

Previous red knot posts:See these previous posts on this subject for more background information and links to scientific papers: Horseshoe Crabs and Red Knots Revisited ( 21 Dec 2010), Ecosystem Connections: Humans, Horseshoe Crabs and Red Knot (16 May 2008) , Red Knot Migration and Horseshoe Crab Egg Abundance Continued (13 Aug 2011), and More on Red Knot Migration: Foraging Conditions in Tierra del Fuego (25 Sept 2011).

An Interesting Mix of Conservation-related Analyses - updated April 1, 2012

noreply@blogger.com (Ian Parnell) — Fri, 23 Dec 2011 18:09:00 +0000

Links to an interesting mix of conservation-related analyses.

Last updated: April 1, 2012
ESA Online Journals - Mapping where ecologists work: biases in the global distribution of terrestrial ecological observations: Mapping where ecologists work: biases in the global distribution of terrestrial ecological observations

Ocean climate variability links incubation behaviour and fitness in Ancient Murrelets (Synthliboramphus antiquus) - Canadian Journal of Zoology: Ocean climate variability links incubation behaviour and fitness in Ancient Murrelets (Synthliboramphus antiquus)

PLoS ONE: Mapping Migratory Bird Prevalence Using Remote Sensing Data Fusion: Mapping Migratory Bird Prevalence Using Remote Sensing Data Fusion. Open Access.

Identifying mismatches between habitat selection and habitat quality in a ground-nesting farmland bird - Gilroy - 2011 - Animal Conservation - Wiley Online Library: Identifying mismatches between habitat selection and habitat quality in a ground-nesting farmland bird. Open Access

ScienceDirect - Trends in Ecology & Evolution : Time for a change: dynamic urban ecology: Time for a change: dynamic urban ecology

Nest-site selection in the Canada Warbler (Wilsonia canadensis) in central New Hampshire - Canadian Journal of Zoology: Nest-site selection in the Canada Warbler (Wilsonia canadensis) in central New Hampshire

Avian responses to experimental harvest in southern boreal mixedwood shoreline forests: implications for riparian buffer management - Canadian Journal of Forest Research: Avian responses to experimental harvest in southern boreal mixedwood shoreline forests: implications for riparian buffer management

PLoS ONE: Avian Conservation Practices Strengthen Ecosystem Services in California Vineyards: Avian Conservation Practices Strengthen Ecosystem Services in California Vineyards

PLoS ONE: Noise Pollution Filters Bird Communities Based on Vocal Frequency: Noise Pollution Filters Bird Communities Based on Vocal Frequency

ScienceDirect - Forest Ecology and Management : Do mature forest birds prefer early-successional habitat during the post-fledging period?: Do mature forest birds prefer early-successional habitat during the post-fledging period?

Spatial ecology and core-area protection of Blanding’s Turtle (Emydoidea blandingii) - Canadian Journal of Zoology: Spatial ecology and core-area protection of Blanding’s Turtle (Emydoidea blandingii)

ScienceDirect - Trends in Ecology & Evolution : Minimum viable population size: not magic, but necessary: Minimum viable population size: not magic, but necessary

PLoS ONE: Identifying and Prioritizing Greater Sage-Grouse Nesting and Brood-Rearing Habitat for Conservation in Human-Modified Landscapes: Identifying and Prioritizing Greater Sage-Grouse Nesting and Brood-Rearing Habitat for Conservation in Human-Modified Landscapes

ScienceDirect - Trends in Ecology & Evolution : A general target for MVPs: unsupported and unnecessary: A general target for MVPs: unsupported and unnecessary

PLoS ONE: Maladaptive Habitat Selection of a Migratory Passerine Bird in a Human-Modified Landscape: Maladaptive Habitat Selection of a Migratory Passerine Bird in a Human-Modified Landscape

ScienceDirect - Biological Conservation : Seeds in farmland food-webs: Resource importance, distribution and the impacts of farm management: Seeds in farmland food-webs: Resource importance, distribution and the impacts of farm management

SpringerLink - Environmental Management, Online First™: Integrating Ecological Knowledge, Public Perception and Urgency of Action into Invasive Species Management

Influence of forest management on pre- and post-fledging productivity of a Neotropical migratory songbird in a highly fragmented landscape - Canadian Journal of Forest Research: Influence of forest management on pre- and post-fledging productivity of a Neotropical migratory songbird in a highly fragmented landscape

Productivity Is a Poor Predictor of Plant Species Richness: Productivity Is a Poor Predictor of Plant Species Richness

Biodiversity and Productivity: Biodiversity and Productivity

BioOne Online Journals - Marking Ruby-Throated Hummingbirds with Radio Frequency Identification Tags: Marking Ruby-Throated Hummingbirds with Radio Frequency Identification Tags

ScienceDirect - Forest Ecology and Management : Effects of even-aged timber harvest on stream salamanders: Support for the evacuation hypothesis: Effects of even-aged timber harvest on stream salamanders: Support for the evacuation hypothesis

ScienceDirect - Biological Conservation : Using multi-scale modelling to predict habitat suitability for species of conservation concern: The grey long-eared bat as a case study: Using multi-scale modelling to predict habitat suitability for species of conservation concern: The grey long-eared bat as a case study

ScienceDirect - Trends in Ecology & Evolution : Minimum viable populations: is there a ‘magic number’ for conservation practitioners?: Minimum viable populations: is there a ‘magic number’ for conservation practitioners?

Genetic mating system and population history of the endangered Western Yellow-breasted Chat (Icteria virens auricollis) in British Columbia, Canada - Canadian Journal of Zoology: Genetic mating system and population history of the endangered Western Yellow-breasted Chat (Icteria virens auricollis) in British Columbia, Canada

PLoS ONE: Collision Mortality Has No Discernible Effect on Population Trends of North American Birds: Collision Mortality Has No Discernible Effect on Population Trends of North American Birds

ESA Online Journals - Woodpeckers, decay, and the future of cavity-nesting vertebrate communities worldwide: Woodpeckers, decay, and the future of cavity-nesting vertebrate communities worldwide

Stable isotopes reveal strategic allocation of resources during juvenile development in a cryptic and threatened seabird, the Marbled Murrelet (Brachyramphus marmoratus) - Canadian Journal of Zoology: Stable isotopes reveal strategic allocation of resources during juvenile development in a cryptic and threatened seabird, the Marbled Murrelet (Brachyramphus marmoratus)

ScienceDirect - Biological Conservation : Predation determines the outcome of 10 reintroduction attempts in arid South Australia: Predation determines the outcome of 10 reintroduction attempts in arid South Australia

Pallid bat (Antrozous pallidus) foraging over native and vineyard habitats in British Columbia, Canada - Canadian Journal of Zoology: Pallid bat (Antrozous pallidus) foraging over native and vineyard habitats in British Columbia, Canada

Economic and geographic drivers of wildlife consumption in rural Africa: Economic and geographic drivers of wildlife consumption in rural Africa

ESA Online Journals - Comparison of statistical and theoretical habitat models for conservation planning: the benefit of ensemble prediction: Comparison of statistical and theoretical habitat models for conservation planning: the benefit of ensemble prediction

ESA Online Journals - Where the wild things are: predicting hotspots of seabird aggregations in the California Current System: Where the wild things are: predicting hotspots of seabird aggregations in the California Current System

BioOne Online Journals - Habitat Suitability and Nest Survival of White-Headed Woodpeckers in Unburned Forests of Oregon: "Habitat Suitability and Nest Survival of White-Headed Woodpeckers in Unburned Forests of Oregon"

BioOne Online Journals - Sufficiency of Horseshoe Crab Eggs for Red Knots During Spring Migration Stopover in Delaware Bay USA: "Sufficiency of Horseshoe Crab Eggs for Red Knots During Spring Migration Stopover in Delaware Bay USA"

PLoS ONE: Aggregating, Tagging and Integrating Biodiversity Research: "Aggregating, Tagging and Integrating Biodiversity Research" Open Access.

Trophic theory of island biogeography - Gravel - 2011 - Ecology Letters - Wiley Online Library: "Trophic theory of island biogeography"

BioOne Online Journals - Modeling Nest Survival of Cavity-Nesting Birds in Relation to Postfire Salvage Logging: "Modeling Nest Survival of Cavity-Nesting Birds in Relation to Postfire Salvage Logging"

PLoS ONE: Egg Production in a Coastal Seabird, the Glaucous-Winged Gull (Larus glaucescens), Declines during the Last Century: "Egg Production in a Coastal Seabird, the Glaucous-Winged Gull (Larus glaucescens), Declines during the Last Century" Open Access.

ScienceDirect - Forest Ecology and Management : Combined long-term effects of variable tree regeneration and timber management on forest songbirds and timber production: "Combined long-term effects of variable tree regeneration and timber management on forest songbirds and timber production"

Analyzing Variability and the Rate of Decline of Migratory Shorebirds in Moreton Bay, Australia - WILSON - 2011 - Conservation Biology - Wiley Online Library: "Analyzing Variability and the Rate of Decline of Migratory Shorebirds in Moreton Bay, Australia"

Population Bottlenecks and Increased Hatching Failure in Endangered Birds - HEBER - 2010 - Conservation Biology - Wiley Online Library: "Population Bottlenecks and Increased Hatching Failure in Endangered Birds"

Population Viability Analysis with Species Occurrence Data from Museum Collections - SKARPAAS - 2011 - Conservation Biology - Wiley Online Library: "Population Viability Analysis with Species Occurrence Data from Museum Collections"

Habitat Loss and Fragmentation

noreply@blogger.com (Ian Parnell) — Sat, 19 Nov 2011 00:58:00 +0000

Evaluating the Effectiveness of Conservation Actions - updated May 6, 2012

noreply@blogger.com (Ian Parnell) — Sat, 08 Oct 2011 18:29:00 +0000

Here is a growing list of articles relevent to evaluating the effectiveness of conservation actions.

Last updated: May 6, 2012

Most recently added:
PLoS ONE: Protecting Endangered Species: Do the Main Legislative Tools Work?: Protecting Endangered Species: Do the Main Legislative Tools Work?

Evaluating indices of conservation success: a comparative analysis of outcome- and output-based indices - Howe - 2012 - Animal Conservation - Wiley Online Library: Evaluating indices of conservation success: a comparative analysis of outcome- and output-based indices

Measures to reduce population fragmentation by roads: what has worked and how do we know? 10.1016/j.tree.2012.01.015 : Trends in Ecology & Evolution | ScienceDirect.com: Measures to reduce population fragmentation by roads: what has worked and how do we know?

PLoS ONE: Recurrent Die-Offs of Adult Coho Salmon Returning to Spawn in Puget Sound Lowland Urban Streams: Recurrent Die-Offs of Adult Coho Salmon Returning to Spawn in Puget Sound Lowland Urban Streams

Assessing the Effectiveness of Marine Reserves on Unsustainably Harvested Long-Lived Sessile Invertebrates - LINARES - 2011 - Conservation Biology - Wiley Online Library: Assessing the Effectiveness of Marine Reserves on Unsustainably Harvested Long-Lived Sessile Invertebrates

Improving biodiversity monitoring - LINDENMAYER - 2011 - Austral Ecology - Wiley Online Library: Improving biodiversity monitoring

Incorporating Effectiveness of Community-Based Management in a National Marine Gap Analysis for Fiji - MILLS - 2011 - Conservation Biology - Wiley Online Library: Incorporating Effectiveness of Community-Based Management in a National Marine Gap Analysis for Fiji

SpringerLink - Journal of Coastal Conservation, Volume 15, Number 1: Evaluating the effects of foraging habitat restoration on shorebird reproduction: the importance of performance criteria and comparative design
Annie F. McIntyre

ScienceDirect - Trends in Ecology & Evolution : Adaptive monitoring in the real world: proof of concept: Adaptive monitoring in the real world: proof of concept

ESA Online Journals - River restoration success: a question of perception: River restoration success: a question of perception. (several 'effectiveness of restoration' articles in this issue)

Contributions of the US state park system to nature recreation: "Contributions of the US state park system to nature recreation" Open Access.

Carbon debt of Conservation Reserve Program (CRP) grasslands converted to bioenergy production: "Carbon debt of Conservation Reserve Program (CRP) grasslands converted to bioenergy production" Open Access.

ScienceDirect - Trends in Ecology & Evolution : Conservation successes at micro-, meso- and macroscales: "Conservation successes at micro-, meso- and macroscales"

ESA Online Journals - Effects of urbanization and urban stream restoration on the physical and biological structure of stream ecosystems.: "Effects of urbanization and urban stream restoration on the physical and biological structure of stream ecosystems."

Avian nest success, mammalian nest predator abundance, and invertebrate prey availability in a fragmented landscape - Canadian Journal of Zoology: "Avian nest success, mammalian nest predator abundance, and invertebrate prey availability in a fragmented landscape"

More on Red Knot Migration: Foraging Conditions in Tierra del Fuego

noreply@blogger.com (Ian Parnell) — Sun, 25 Sep 2011 15:43:00 +0000

A recent paper on red knot migration describes factors at the southern end of their migration route in Tierra del Fuego that may contribute to their decline in numbers, in addition to foraging conditions at the Delaware Bay migration stop-over area.

Escudero et al. (2011) studied foraging conditions at the southern end of red knot migration, a major over wintering site in Argentinean Tierra del Fuego (e.g. see here and here). In particular, they looked at " . . . food abundance, diet and intake rates during January–February in 1995, 2000 and 2008."

They found that in 2000, a year of extremely low migration survival for red knot which coincided with low egg deposition by horseshoe crabs at the Delaware Bay stop-over site(e.g., Baker et al. 2004), foraging at the Tierra del Fuego site was excellent relative to other known over-wintering sites. However, in 2008 foraging success at the southern site declined due to smaller prey and increased human disturbance.

The authors suggest that in 2000, red knot didn't face problems in the Tierra del Fuego overwintering area, which would be consistent with the previous evidence that problems at northern stop-overs negatively affected red knot survival.

However, the poor foraging condition in 2008 could have further contributed to the decline in red knot numbers, and they conclude this finding emphasizes the need for a broader, hemispheric approach, to red knot research and management.

Previous red knot posts:See these previous posts on this subject for more background information and links to scientific papers: Horseshoe Crabs and Red Knots Revisited, Ecosystem Connections: Humans, Horseshoe Crabs and Red Knot and Red Knot Migration and Horseshoe Crab Egg Abundance Continued

References:
ESCUDERO, G., NAVEDO, J. G., PIERSMA, T., DE GOEIJ, P. and EDELAAR, P. (2011), Foraging conditions ‘at the end of the world’ in the context of long-distance migration and population declines in red knots. Austral Ecology. doi: 10.1111/j.1442-9993.2011.02283.x

Rapid population decline in red knots: fitness consequences of decreased refuelling rates and late arrival in Delaware Bay.: Rapid population decline in red knots: fitness consequences of decreased refuelling rates and late arrival in Delaware Bay.

Foraging conditions ‘at the end of the world’ in the context of long-distance migration and population declines in red knots - ESCUDERO - 2011 - Austral Ecology - Wiley Online Library: Foraging conditions ‘at the end of the world’ in the context of long-distance migration and population declines in red knots

Red Knot Superstar “B-95” Seen Again in Tierra del Fuego, Argentina! | WHSRN.org: Red Knot Superstar “B-95” Seen Again in Tierra del Fuego, Argentina!

Shorebird Researchers Document Red Knot's Record-breaking Non-stop Flight and Total Migration Distance: Shorebird Researchers Document Red Knot's Record-breaking Non-stop Flight and Total Migration Distance

Marine Conservation Literature - updated March 2, 2012

noreply@blogger.com (Ian Parnell) — Sat, 20 Aug 2011 02:31:00 +0000

Here is a growing collection of links to interesting looking papers relevant to marine conservation.

Last updated: March 2, 2012

Most recently added:
A cold oceanographic regime with high exploitation rates in the Northeast Pacific forecasts a collapse of the sardine stock: A cold oceanographic regime with high exploitation rates in the Northeast Pacific forecasts a collapse of the sardine stock

ESA Online Journals - Life-history correlates of extinction risk and recovery potential: Life-history correlates of extinction risk and recovery potential

Extinction risk and bottlenecks in the conservation of charismatic marine species - McClenachan - 2011 - Conservation Letters - Wiley Online Library: Extinction risk and bottlenecks in the conservation of charismatic marine species

PLoS ONE: Competing Conservation Objectives for Predators and Prey: Estimating Killer Whale Prey Requirements for Chinook Salmon: Competing Conservation Objectives for Predators and Prey: Estimating Killer Whale Prey Requirements for Chinook Salmon

Reexamining the science of marine protected areas: linking knowledge to action - Fox - Conservation Letters - Wiley Online Library: Reexamining the science of marine protected areas: linking knowledge to action

Fisheries conservation and management: finding consensus in the midst of competing paradigms - Branch - 2011 - Animal Conservation - Wiley Online Library: Fisheries conservation and management: finding consensus in the midst of competing paradigms

PLoS ONE: Global Conservation Priorities for Marine Turtles: Global Conservation Priorities for Marine Turtles. Open Access.

ScienceDirect - Biological Conservation : Cumulative estimates of sea turtle bycatch and mortality in USA fisheries between 1990 and 2007: Cumulative estimates of sea turtle bycatch and mortality in USA fisheries between 1990 and 2007

ScienceDirect - Biological Conservation : Small marine reserves can offer long term protection to an endangered fish: Small marine reserves can offer long term protection to an endangered fish

ScienceDirect - Trends in Ecology & Evolution : Recovery of marine animal populations and ecosystems: Recovery of marine animal populations and ecosystems

Seasonal patterns in bycatch composition and mortality associated with a freshwater hoop net fishery - Larocque - 2011 - Animal Conservation - Wiley Online Library: Seasonal patterns in bycatch composition and mortality associated with a freshwater hoop net fishery

PLoS ONE: Large Recovery of Fish Biomass in a No-Take Marine Reserve: "Large Recovery of Fish Biomass in a No-Take Marine Reserve" Open Access.

National Geographic article: http://newswatch.nationalgeographic.com/2011/08/12/an-ocean-miracle-in-the-gulf-of-california%e2%80%93can-we-have-more-of-this-please/

Role of egg predation by haddock in the decline of an Atlantic herring population: "Role of egg predation by haddock in the decline of an Atlantic herring population"

Inter Research » ESR » v11 » n3 » p245-269: "Global research priorities for sea turtles: informing management and conservation in the 21st century" Open Access.

Global distribution and conservation of marine mammals: "Global distribution and conservation of marine mammals"

Small-scale fisheries of Peru: a major sink for marine turtles in the Pacific - Alfaro-Shigueto - 2011 - Journal of Applied Ecology - Wiley Online Library: "Small-scale fisheries of Peru: a major sink for marine turtles in the Pacific" Open Access.

SpringerLink - Environmental Management, Online First™: "Global Marine Protection Targets: How S.M.A.R.T are They?"

Significant Arctic fish catches going unreported: UBC researchers warn: "Significant Arctic fish catches going unreported: UBC researchers warn"

PLoS ONE: Global Diversity Hotspots and Conservation Priorities for Sharks: "Global Diversity Hotspots and Conservation Priorities for Sharks"

Unexpected patterns of fisheries collapse in the world's oceans: "Unexpected patterns of fisheries collapse in the world's oceans"

Great white shark population lower than previously believed - CSMonitor.com: "Great white shark population lower than previously believed"

CITES meeting rejects protection for marine species - CSMonitor.com: "CITES meeting rejects protection for marine species"

ESA Online Journals - Fish farms, parasites, and predators: implications for salmon population dynamics: "Fish farms, parasites, and predators: implications for salmon population dynamics"

Red Knot Migration and Horseshoe Crab Egg Abundance Continued

noreply@blogger.com (Ian Parnell) — Sat, 13 Aug 2011 14:40:00 +0000

Here are some recent papers about western Atlantic red knot (Calidris canutus rufa) migration and horseshoe crab egg abundance in Delaware Bay, USA.

Karpanty et al. (2011) examined the relationship between the temporal and spatial distribution of horseshoe crab eggs and red knot migration timing in 2004 and 2005 (see here). They found that there was a sufficient abundance of horseshoe crab eggs to sustain the red knot migration, at least at the current red knot population size, but noted that this finding does not rule out the hypothesis the observed decline in the red knot population is related to the decline in the horseshoe crab population and hence horseshoe crab egg abundance. They suggest that if the red knot population does not increase as horseshoe crab egg abundance increases, then managers need to examine other factors and areas.

An important quantitative link in the hypothesis is showing that horseshoe crab egg abundance affects red knot survival on the northward migration to their breeding grounds in the Canadian arctic. McGowan et al. (2011) addressed this link by modelling the relationship between weight gain (mass gain) and the ensuing apparent survival of red knot in relation to horseshoe crab egg abundance (see here). They used a relatively long data set (for ecology) capture-recapture/resighting data with over 16,000 individual captures and 13,000 resightings collected in Delaware Bay (12 years from 1997-2008) and found a positive relationship between horseshoe crab spawning abundance and red knot weight gain, mass and apparent annual survival. This suggests that management to increase horseshoe crab abundance in the Delaware Bay (e.g., reduce harvest) can potentially increase the red knot population.

Smith et al. (2011) looked at how weather can affect red knot foraging opportunities on horseshoe crab eggs in Delaware Bay as a variation on the match/mismatch hypothesis (see here). They found that onshore winds can disrupt foraging opportunities in certain locations and suggest that in addition to managing the harvest of horseshoe crabs to ensure adequate abundance of eggs available during migration, that it is also important to conserve beach areas that are resistant to such weather related impacts on foraging opportunities for migrating red knot on horseshoe crab eggs.

See these previous posts on this subject for more background information and links to scientific papers: Horseshoe Crabs and Red Knots Revisited and Ecosystem Connections: Humans, Horseshoe Crabs and Red Knot

References:

Karpanty, S.M., J. Cohen, J.D. Fraser and J. Berkson. 2011. Sufficiency of Horseshoe Crab Eggs for Red Knots During Spring Migration Stopover in Delaware Bay USA. Journal of Wildlife Management Jul 2011 : Vol. 75, Issue 5, pg(s) 984-994 doi: 10.1002/jwmg.129

McGowan, C.P., J.E. Hines, J.D. Nichols, J.E. Lyons, D.R. Smith, K.S. Kalasz, L.J. Niles, A.D. Dey, N.A. Clark, P.W. Atkinson, C.D.T. Minton, and W. Kendall. 2011. Demographic consequences of migratory stopover: linking red knot survival to horseshoe crab spawning abundance. Ecosphere 2:art69.[doi:10.1890/ES11-00106.1]

Smith, D. R., N.L. Jackson, K.F. Nordstrom and R.G. Weber, R. G. 2011. Beach characteristics mitigate effects of onshore wind on horseshoe crab spawning: implications for matching with shorebird migration in Delaware Bay. Animal Conservation. doi: 10.1111/j.1469-1795.2011.00481.x

Green Grazing: More Articles about Sea Turtle Conservation

noreply@blogger.com (Ian Parnell) — Sun, 07 Aug 2011 22:25:00 +0000

Here are links to recent articles and blogs about sea turtle conservation. First, new research shows how loggerhead turtles use the earth's magnetic field to navigate the thousands of miles along their oceanic migration routes during the years they spend at sea after hatching. Not only may these results be useful in sea turtle conservation, they may also bring new insights into navigation technology for humans. The International Union for the Conservation of Nature (IUCN) categorizes loggerhead sea turles as endangered. (see BBC News - Sea turtles' migration mystery is 'solved'). In a second story, U.S. conservations are pushing for regulatory action under the Endangered Species Act for the leatherback turtle along the U.S. West Coast (see World Environment News - Conservationists Push Action On Protected Turtles - Planet Ark). Finally, here is an interesting blog post from a marine conservation scientist travelling to Ecuador to research the effectiveness of efforts to encourage fishers to use marine conservation technologies, including special fish hooks, to reduce the unintentional catch of sea turtles (bycatch) (see To Ecuador, With Sea Turtles in Mind - NYTimes.com).

Pollinator papers - last updated May 24, 2012

noreply@blogger.com (Ian Parnell) — Sat, 30 Jul 2011 18:19:00 +0000

An eclectic and growing collection of pollinator papers and articles.

Last updated: May 24, 2012
PLoS ONE: Insect Pollinated Crops, Insect Pollinators and US Agriculture: Trend Analysis of Aggregate Data for the Period 1992–2009: Insect Pollinated Crops, Insect Pollinators and US Agriculture: Trend Analysis of Aggregate Data for the Period 1992–2009. Open Access. ESA Online Journals - Roles of scale, matrix and native habitat in supporting a diverse suburban pollinator assemblage: Roles of scale, matrix and native habitat in supporting a diverse suburban pollinator assemblage
PLoS ONE: Spatial and Temporal Trends of Global Pollination Benefit: Spatial and Temporal Trends of Global Pollination Benefit ScienceDirect.com - Biological Conservation - Supporting wild pollinators in a temperate agricultural landscape: Maintaining mosaics of natural features and production: Supporting wild pollinators in a temperate agricultural landscape: Maintaining mosaics of natural features and production Do pathogen spillover, pesticide use, or habitat loss explain recent North American bumblebee declines? - Szabo - Conservation Letters - Wiley Online Library: Do pathogen spillover, pesticide use, or habitat loss explain recent North American bumblebee declines?

PLoS ONE: Organic Farming Improves Pollination Success in Strawberries: Organic Farming Improves Pollination Success in Strawberries

Significant expansion of the distribution of the bumble bee Bombus moderatus (Hymenoptera: Apidae) in Alberta over 20 years11 This paper is dedicated to the memory of Adolf Scholl. - Canadian Journal of Zoology: Significant expansion of the distribution of the bumble bee Bombus moderatus (Hymenoptera: Apidae) in Alberta over 20 years

ESA Online Journals - Landscape-scale resources promote colony growth but not reproductive performance of bumble bees: Landscape-scale resources promote colony growth but not reproductive performance of bumble bees

PLoS ONE: Field Margins, Foraging Distances and Their Impacts on Nesting Pollinator Success: Field Margins, Foraging Distances and Their Impacts on Nesting Pollinator Success. Open Access.

PLoS ONE: Quantitative Historical Change in Bumblebee (Bombus spp.) Assemblages of Red Clover Fields: Quantitative Historical Change in Bumblebee (Bombus spp.) Assemblages of Red Clover Fields. Open Access.

ScienceDirect - Biological Conservation : Gardens benefit bees and enhance pollination in intensively managed farmland: "Gardens benefit bees and enhance pollination in intensively managed farmland"

Pollination ecology in the 21st century: key questions for future research - Parade@Portsmouth: "Pollination ecology in the 21st century: key questions for future research"

Mayer, C., Adler, L., Armbruster, Scott, Dafni, A., Eardley, C., Huang, S., Kevan, P., Ollerton, J., Packer, L. and Ssymank, A. (2011) Pollination ecology in the 21st century: key questions for future research. Journal of Pollination Ecology, 3 (2). pp. 8-23. ISSN 1920-7603

Stability of pollination services decreases with isolation from natural areas despite honey bee visits - Garibaldi - 2011 - Ecology Letters - Wiley Online Library: "Stability of pollination services decreases with isolation from natural areas despite honey bee visits" Open Access.

Translating research into action; bumblebee conservation as a case study - Goulson - 2010 - Journal of Applied Ecology - Wiley Online Library: "Translating research into action; bumblebee conservation as a case study" This paper is Open Access.

Bumble bee species' responses to a targeted conservation measure depend on landscape context and habitat quality

SpringerLink - Environmental Management, Online First™: "Honeybees Increase Fruit Set in Native Plant Species Important for Wildlife Conservation"

PLoS ONE: Space Use of Bumblebees (Bombus spp.) Revealed by Radio-Tracking: "Space Use of Bumblebees (Bombus spp.) Revealed by Radio-Tracking"

PLoS ONE: A Quantitative Model of Honey Bee Colony Population Dynamics: "A Quantitative Model of Honey Bee Colony Population Dynamics"

Decision-making in Conservation - update February 25, 2012

noreply@blogger.com (Ian Parnell) — Wed, 27 Jul 2011 02:49:00 +0000

Green Grazing: Some Good News for Sharks

noreply@blogger.com (Ian Parnell) — Sat, 19 Feb 2011 06:46:00 +0000

Finally, some good news for sharks on both the recreational and commercial fishing fronts.

Sports fishermen in British Columbia have agreed to support the development of new federal sportfishing regulations to reduce the catch of sharks off the province's coast (see here). The new regulation would ban fishing for sharks for which there is a science-based conservation concern and any sharks caught by accident would have to be released. This ban will include the Tope, wide ranging pacific shark species that is, unfortunately for it, also known as the soupfin shark, and listed as 'special concern' under Canada's federal Species at Risk Act.

Meanwhile, across the border in the United States congress recently brought in a law prohibiting catching sharks and taking only their fins (known as 'finning') in U.S. waters (see here). Now boats have to bring sharks into port with the fins attached. Since whole sharks take up more room than just fins, this reduces the number of sharks killed by each vessel.

Beyond Ocean Fertilization: The CBD Moratorium on Geoengineering

noreply@blogger.com (Ian Parnell) — Fri, 04 Feb 2011 02:41:00 +0000

After last week's post on the recent UN report on ocean fertilization, I came across an interesting post on the blog Resilience Science that does a great job of contrasting two points of view about the potential effectiveness of a recent moratorium on geoengineering (see A Moratorium on Geoengineering? Really?). Effectiveness in this case is the likelihood of this moratorium actually controlling the implementation of large-scale geoengineering experiments or projects at the international scale.

The participants in the international Convention on Biological Diversity (CBD) included this moratorium in their October 2010 agreement to protect biodiversity (the CBD previously called for a ban on ocean fertilization in 2008). The post has lots of useful links to background information on the CBD, other reports on geoengineering (pro and con), as well as general material about the potential role for geoengineering in combating global warming.

cheers.

Ocean Fertilization: Is the Verdict In?

noreply@blogger.com (Ian Parnell) — Thu, 03 Feb 2011 03:42:00 +0000

I found this article on Planet Ark - Fertilizing Oceans seen fruitless in climate fight. It's about a recent UN report on the utility of ocean fertilization (see here and here) as a tool for fighting climate change by absorbing carbon from the atmosphere. Some of the issues raised in the report were:

It's hard to monitor ocean fertilization's effectiveness, which is key both for carbon credits and understanding impacts on ocean ecosystems.
It can only store relatively small amounts of carbon dioxide; only about 1-15% of the carbon taken up during nutrient stimulate phytoplankton blooms rains into the deep as 'marine snow' (the tiny carcasses of dead plankton).
It has a low chance of success; the results of a number of large experiments over recent years have brought declining optimism about it.
It might help grow fish in some places, but rob the ocean of nutrients in others.

The report was also skeptical about the utility of 'ocean pipes' for drawing naturally occurring nutrients to the ocean's surface waters.

Here's the the link to the UN report - Ocean Fertilization: A scientific summary for policy makers

Cheers.

Green Grazing: Penguins, Turtles and Whales

noreply@blogger.com (Ian Parnell) — Sun, 23 Jan 2011 18:19:00 +0000

Here are links to some articles on penguins, turtles and whales that captured my attention over the last couple of weeks. The common thread is how new technologies are helping scientists learn about the secrets of wide ranging and hard to observe animals, and also that there is still a lot to learn about the world around us.

Penguins
The 30 second summary: Scientists have found that penguins banded with traditional flipper-bands are at a survival disadvantage compared to unbanded penguins. Banded king penguins didn't live as long, had fewer chicks and exhibited delayed migration-timing relative to unbanded penguins. These results need to be taken into account when interpreting changes in penguin mortality rates over time relative to factors such as fishing and climate change.

The news article: Black, R. (January 12, 2011). 'Unethical' flipper tags are damaging to penguins. BBC News website.

The scientific paper: Saraux, C., C. Le Bohec, J.M. Durant, V.A. Viblanc, M. Gauthier-Clerc, D. Beaune, Y. Park, N.G. Yoccoz, N.C. Stenseth and Y. Le Maho. 2011. Reliability of flipper-banded penguins as indicators of climate change. Nature, 469: 203–206, (13 January 2011), doi:10.1038/nature09630, Received 26 August 2010 Accepted 29 October 2010. Published online12 January 2011.

Turtles
The 30 second summary: Researchers tracked leatherback turtles nesting on the beaches of the African nation of Gabon on their post-nesting treks through the Atlantic and found that they frequent three areas, probably due to the initial areas they were carried to by currents when they first entered the ocean upon hatching. Information shows that they end up in some of the most heavily fished areas of the sea. This data will be useful for conservation purposes as it shows the turtles, for example, traverse the coastal waters of 11 nations as they move down the Atlantic coast of Africa. They are in danger of becoming by-catch in longline fisheries and from being entangled in gillnets used in coastal fisheries.

The news story: Black, R. (January 5, 2011). Leatherback turtles tracked on Atlantic 'danger' trips. BBC News website. (Accessed January 9, 2011)

The scientific paper: Witt, M.J. et al. 2011. Tracking leatherback turtles from the world's largest rookery: assessing threats across the South Atlantic. Proc. R. Soc. B, Published online before print January 5, 2011, doi: 10.1098/rspb.2010.2467

Whales
The 30 second summary: Scientists have found that Transient Killer whales in the eastern pacific prey heavily upon young grey whales, eating up to third of the calves born each year. Not only that, but the Killer whales also store the carcasses, a behaviour not previously observed. Because the whales store and feed on the carcasses in shallow nearshore waters, the dead grey whale calves also provide food for Alaskan bears and sleeper sharks (ironically, another group of Killer whales appears to feed almost exclusively on sleeper sharks).

The news story: Lavoie, J. (January 22, 2011). A third of young grey whales eaten by killer whales, scientists say. The Vancouver Sun.

The scientific paper: Barrett-Lennard LG, Matkin CO, Durban JW, Saulitis EL, Ellifrit D (2011) Predation on gray whales and prolonged feeding on submerged carcasses by transient killer whales at Unimak Island, Alaska. Mar Ecol Prog Ser 421:229-241

Cheers

Tumbling Bumble bees

noreply@blogger.com (Ian Parnell) — Thu, 06 Jan 2011 04:33:00 +0000

This week's hot science story is about declines in North American bumble bees. A paper just published online in the journal Proceedings of the National Academy of Sciences (PNAS) has been getting a lot of press, with articles appearing in numerous print and online media sources (e.g., see here, here and here . . . ). The researchers studied 8 of the 50 bumble bee species found in North America and found large declines in four of them. It appears that like the honey bee and Nosema ceranae, bumble bee declines may be partially due to a pathogen, Nosema bombis. Here's the link to the paper:

Cameron, S.A., J.D. Lozier, J.P. Strange, J.B. Koch, N. Cordes, L.F. Solter and T.L. Griswold. 2011. Patterns of widespread decline in North American bumble bees. PNAS January 3, 2011, doi: 10.1073/pnas.1014743108

The Power of the Press Release Redux

noreply@blogger.com (Ian Parnell) — Fri, 31 Dec 2010 06:05:00 +0000

A couple of years ago I wrote a post about a modern press campaign and its influence on the public understanding of a scientific paper and its relative importance (see here). The paper in question addressed a breakthrough in the study of Colony Collapse Disorder (CCD), which at the time was much in the press. Several press releases hinted and many news articles boldly stated that the research presented in the paper showed CCD was caused by a virus, the Israeli Acute Paralysis Virus (IAPV), though I should make it clear the paper's authors did themselves make such a strong claim themselves.

Well, time has passed and the scientific process has tested the IAPV-CCD hypothesis. Subsequent research has been unable to corroborate the original findings and it fallen by the wayside as more convincing evidence arises for other causes (e.g. the microsporidian Nosema ceranae). In short, while the research was an important part of the science behind understanding CCD, it was not the breakthrough that the press juggernaut conveyed.

The IAPV-CCD juggernaut was launched by savvy use of new media technology to publicize science and accelerated by the public need to know more, or at least something, about the cause of the mysterious disappearance of honey bees across the United States.

A more recent example of this phenomenon comes from a press campaign by NASA that seems to similarly have gone awry. Hints of a big announcement from NASA scientists were followed, somewhat anticlimactically (I think many were expecting an announcement of the discovery of extraterrestrial life), by a press release from NASA scientists reporting the discovery of a species of bacteria capable of incorporating arsenic into its DNA structure in place of phosphorous, a finding at odds with prior understanding and which suggested that the search for extraterrestrial life was perhaps too narrowly focused.

This reminded me of the IAPV story because the hype was incredible for a story that turned out to be not nearly as interesting to the general public as, say, the discovery of actual extraterrestrial life. Perhaps even more odd that the IAPV story because it was not in relation to an issue currently high in the public radar as CCD was, and especially as it was hard to explain to the public - so the bacteria use arsenic instead of phosphorous, so what? Important yes, exciting, perhaps not if you don't study bacteria and think deeply about the conditions necessary to support extraterrestrial life. Yet, there it was in the news, on the Internet, on TV and in the newspaper for what seemed like days.

It seems that we've learned how to market science really well on the Internet, now we just need to learn the appropriate intensity at which to do it.

For more details about the bacteria-phosphorous research and its repercussions from a more scholarly angle read this interesting post from RealClimate.org that looks at this story and the controversy it generated as an example the scientific process in action (see here).

If you find this interesting, you might also want to check out another recent article on scientific peer review on the blog Dot Earth: On Warming, Antarctica, Clouds and Peer Review

Cheers.

Managing Nutrient Pollution in Coastal Ecosystems: Two Examples

noreply@blogger.com (Ian Parnell) — Thu, 30 Dec 2010 17:16:00 +0000

Excess nutrients entering the ocean from sources like the runoff of agricultural fertilizers pose serious problems for coastal marine ecosystems.In some cases, hypoxic (low oxygen) 'dead zones' form, reducing marine biodiversity, fish habitat, and ultimately impacting fisheries (e.g., see here and here). Two well known examples of coastal ecosystems impacted by nutrient pollution are the Gulf of Mexico and Chesapeake Bay.

Two recent scientific papers provide interesting examples of different, but equally important approaches to the challenge of managing nutrient pollution, forecasting its impacts and assessing management actions intended to reduce it.

Ecosystem modeling is a valuable tool for evaluating trade-offs between environmental policies and management actions (e.g., see here). Evans and Scavia (2011) provide an example of the development and application of ecosystem models for predicting future hypoxic events in both Chesapeake Bay and the Gulf of Mexico. One goal of their analysis is to develop robust approaches to calibrating such models that optimize the accuracy and precision of forecasts for highly variable systems, such as the Bay and the Gulf, are changing over time.

Ruhl and Rybicki(2010) provide a different sort of analysis. Rather than using data to model and forecast future hypoxic conditions in Chesapeake Bay, they analyze past data from 18 years of restoration efforts to understand pattern of change observed in an indicator of ecosystem condition, Submerged Aquatic Vegetation(SAV) (see here). Contrary to general opinion about the ineffectiveness of such actions, their analysis suggests that, ". . . environmental policies that reduce anthropogenic nutrient inputs do result in improved habitat quality, with increased diversity and native species abundances."

Both papers are Open Access.

References for this post:

Evans, M.A. and D. Scavia. 2011. Forecasting hypoxia in the Chesapeake Bay and Gulf of Mexico: model accuracy, precision, and sensitivity to ecosystem change. Environmental Research Letters 6(1): doi: 10.1088/1748-9326/6/1/015001. O/A

Ruhl, H. A. and N. B. Rybicki. 2010. Long-term reductions in anthropogenic nutrients link to improvements in Chesapeake Bay habitat. Published online before print September 7, 2010, doi: 10.1073/pnas.1003590107. O/A

Horseshoe Crabs and Red Knots Revisited

noreply@blogger.com (Ian Parnell) — Wed, 22 Dec 2010 06:08:00 +0000

Here's some more detailed information about horsehoe crabs and red knots as a supplement to my 2008 post, "Ecosystem Connections: Humans, Horseshoe Crabs and Red Knot."

Niles et al. 2009a provide an excellent primer on the important connection between the timing of horseshoe crab spawning and red knot migration in Delaware Bay, including factors driving the decline in the horseshoe crab population, the impact of this decline on red knots, the managment actions taken to address the decline, and the effectiveness of these actions for recovering both horseshoe crabs and red knots. They propose an adaptive management strategy to help recover the red knot and horseshoe crab populations to recover.

As a bonus, I've included links to a couple of follow up papers as an example of the scientific process in action - Smith et al. 2009 critique aspects of the Niles et al. 2009a paper, while Niles et al. 2009b responed to this critique.

Also, as an fyi, there is a link to a paper by Cohen et al. 2010. This paper further expands the science underlying red knot conservation.

References for this post:

Niles LJ, J Bart, HP Sitters, AD Dey, KE Clark, PW Atkinson, AJ Baker, KA Bennett, KS Kalasz, NA Clark, J Clark, S Gillings, AS Gates, PM González, DE Hernandez, CD T Minton, RIG Morrison, RR Porter, RK Ross, CR Veitch. 2009a. Effects of Horseshoe Crab Harvest in Delaware Bay on Red Knots: Are Harvest Restrictions Working? BioScience 59(2): 153–164, doi 10.1525/bio.2009.59.2.8 Posted online on February 11, 2009.

Smith, D.R., E.M. Hallerman, M.J. Millard, J.A. Sweka and R.G. Weber. 2009. An Incomplete Analysis. BioScience 59:7, 541-541. Online publication date: 1-Jul-2009.

Niles L.J., H.P. Sitters, A.D. Dey, J. Bart, A.J. Baker, R.I.G. Morrison, K.S. Kalasz and N.A. Clark. 2009b. Response from Niles and colleagues. BioScience 59:7, 541-542. Online publication date: 1-Jul-2009.

Cohen, J.B., S.M. Karpanty, J.D. Fraser and B.R. Truitt. 2010. The effect of benthic prey abundance and size on red knot (Calidris canutus) distribution at an alternative migratory stopover site on the US Atlantic Coast. J Ornithol (2010) 151:355–364, DOI 10.1007/s10336-009-0462-7.

More research on mosquito-borne viruses in Italy

noreply@blogger.com (Ian Parnell) — Sat, 18 Dec 2010 02:16:00 +0000

More mosquito info:

Calzolari M, Bonilauri P, Bellini R, Albieri A, Defilippo F, et al. 2010 Evidence of Simultaneous Circulation of West Nile and Usutu Viruses in Mosquitoes Sampled in Emilia-Romagna Region (Italy) in 2009. PLoS ONE 5(12): e14324. doi:10.1371/journal.pone.0014324 O/A

see also: Tiger Mosquitoes Tour Italia

Honey Bee Colony Collapse Disorder (CCD) VII: IAPV, Nosema ceranae, and CCD

noreply@blogger.com (Ian Parnell) — Sat, 26 Sep 2009 20:08:00 +0000

Is Colony Collapse Disorder (CCD) caused by new or re-emerging pathogens? This is one hypothesis put forward by US researchers in 2007 and two candidates, the Israeli Acute Paralysis Virus (IAPV) and the microsporidian parasite Nosema ceranae, have received the most mention in the press.

I reviewed the available scientific literature to evaluate the weight of scientific evidence for the role of each pathogen in CCD and found that in terms of both the number of scientific papers and their substantial content the weight of evidence supports Nosema ceranae over IAPV as a cause of CCD, at least in Spain. Additionally, recent research does not support IAPV as a cause of CCD, in either the United States or Europe.

However, despite this evidence, there is a knowledge gap in the literature about the role of Nosema ceranae in CCD in the United States, which may arise from early US research focus on IAPV, the later start on research on IAPV relative to Nosema ceranae, or different causes of CCD in Europe and the United States. More experimental research is required to confirm that Nosema ceranae does, or does not, play a role in CCD in North America.

Until then, the current weight of evidence for a cause-effect link between Nosema ceranae and CCD supports the adoption of precautionary bee-keeping practices that account for it.

Background

Soon after colony collapse disorder (CCD) emerged in 2006, US researchers focused on a suite of hypotheses, one of which was that CCD is caused by new or re-emerging pathogens (see here).

In 2007, a paper in journal Science reported that a relatively new virus, the Israeli Acute Paralysis Virus (IAPV), was associated with observed occurrences of CCD, a finding that not only generated a tremendous amount of press coverage (see here), but some international intrigue as well (see here). As recently as this year, US researchers were still discussing of the role of IAPV in CCD in a general science magazine.

Nosema ceranae, while recognized as an emerging threat to honey bees prior to CCD, was quickly dismissed as a candidate pathogen for CCD by the primary US researchers. Little was written in the general press about Nosema ceranae until early in 2009 when it received its own press boost after a paper was published by Spanish researchers which appeared to convincingly connect it to CCD (see here).

The challenge to the layperson following developments in CCD research is keeping such press reports on scientific research results in perspective. Reporters often rely on press releases prepared by research institutions and may let the researchers themselves place their results in context.

While this is an important part of reporting on science, reporters rarely dig deep enough or follow a particular issue long enough to be able to establish the relative importance of a particular paper for the reader, beyond the immediate research being reported. This is especially the case for a topic as significant, complex and long-lasting as CCD; it is difficult for the interested layperson keep abreast of the research initiatives and findings, many of which are not reported upon in the general press.

The purpose of this analysis, then, is to determine the relative weight of evidence for the role of IAPV and Nosema ceranae as causes of CCD by finding and evaluating the peer-reviewed scientific evidence available for each.

Methods

I used Google Scholar to search the peer-reviewed scientific literature for research papers on both IAPV and Nosema ceranae (search is current up to the date of this posting). For each pathogen, I considered both the number of scientific papers published about it, from its first appearance in the literature until the present, and their substantive nature in relation to CCD. That is, for each pathogen, I considered how directly the observational or experimental evidence reported in the papers supported a cause-effect link between it and CCD.

To make the direct case for a cause-effect link between a particular pathogen and CCD, the research had to show that infection by the pathogen in question caused symptoms of CCD:
1) most adult bees have left and failed to return to the hive leaving the queen behind (uncharacteristic of bee behaviour);
2) colony losses are rapid and occur in large numbers; no dead adult bees are found within or near the hive;
3) delayed honey robbing behaviour from nearby colonies and honey predators (highly unusual); and
4) the few adults found within abandoned colonies are often highly infected with multiple pathogens.

Results

Evidence for a Cause-Effect Link between the Israeli Acute Paralysis Virus (IAPV) and CCD

The first published description of IAPV in the scientific literature is in 2007. Maori et al. (2007) report that following unusually high honey bee colony losses in Israel, they isolated IAPV, a virus closely related to two previously known bee viruses, the kashmir bee virus and acute bee paralysis virus.

[Cox-Foster and vanEngelsdorp (2009) write that IAPV was first described in 2004 by Ilan Sela of the Hebrew University of Jerusalem; however, I could not find a published paper to support this. It may be referenced in another paper as a personal communication, or just common knowledge in the bee virus research community. Sela is a co-author of Maori et al. 2007].

That same year, Cox-Foster et al. (2007) published a paper in the journal Science reporting an association between the presence of IAPV and dead colonies exhibiting the symptoms of CCD. This research received much press, but though it showed an association between IAPV and CCD, it did not establish a causal link between them (Anderson and East 2008). For example, CCD could have made the bees susceptible to IAPV infection (Cox-Foster and vanEngelsdorp 2009).

A third IAPV paper published in 2007 reported that the virus had been present in honey bees in the United States for a number of years prior to the onset of CCD (Chen and Evans 2007). So, if IAPV was a cause of CCD, something must have changed to make it more virulent. This ‘something’ could be a new strain arising through genetic mutation, or the arrival of a more virulent strain from outside the US.

Papers relevant to IAPV and CCD that have been published since Cox-Foster et al. (2007) include:
- Palacios et al. (2008): found distinct clusters of the IAPV virus in the United States.
- Blanchard et al. (2008): reported the first detection of IAPV in France, but their results were inconclusive about its relationship to observed colony losses.
- Maori et al. (2009): reported that IAPV can be ‘silenced’ by dsRNA ingestion, suggesting a potential future treatment for the virus.

None of these papers strengthen the support for IAPV as a cause CCD, and recent research weakens the link even further. vanEngelsdorp et al. (2009) report that a replication of the work reported by Cox-Foster et al (2007) did not show IAPV was associated with CCD – that is, they were unable to replicate those earlier results, though they found that the prevalence of other viruses was generally comparable to the prior results.

In summary, the published scientific evidence on IAPV to date does not support the hypothesis that IAPV is a cause of CCD, however, the primary US researchers of CCD remain convinced that a virus of some kind lies at the bottom of the mystery: “The growing consensus among researchers is that multiple factors such as poor nutrition and exposure to pesticides can interact to weaken colonies and make them susceptible to a virus mediated collapse.” (Cox-Foster and vanEngelsdorp 2009)

Evidence for a Cause-Effect Link between Nosema ceranae and CCD

Meanwhile, in Europe there is little or no support for IAPV as a cause of CCD, but lots for Nosema ceranae. There CCD is also called Honey Bee Colony Depopulation Syndrome (HBDS) and research into the role of Nosema ceranae in honey bee colony losses has been going on since before the onset of CCD in the United States, with the pathogen gradually becoming the primary suspect.

Nosema ceranae is a microsporidian (fungal) parasite of the Asian honeybee Apis ceranae that is closely related to Nosema apis, a long known pathogen of the European honeybee Apis mellifera. Nosema ceranae is first mentioned in the scientific literature as a parasite of Apis ceranae in 1996 (see Fries et al. 1996), but not long after that it emerges as a pathogen of Apis mellifera being reported first in Taiwan by Huang et al. (2007) (research submitted for publication in 2005) and then in Spain (Higes et al. 2006).

Since then, research on N. ceranae has steadily accumulated with the publication of at least twenty more papers. For this analysis, I focused on a subset of those papers that describe N. ceranae’s spatial distribution, its pattern of temporal emergence, and the experimental evidence of its role in honey bee colony collapse; however, the citations for the other papers are also included at the end of this article for those interested.

Spatial Distribution of Nosema ceranae:

Nosema ceranae is now widespread throughout the world as a pathogen of Apis mellifera. Klee et al. (2007) summarised its global dispersal as of 2006, when it was present in at least 15 countries across the Americas and Caribbean (Brazil, Martinique, Washington DC), Asia (Vietnam, Taiwan), Europe and Near East (Denmark, Finland, France, Germany, Greece, Italy, Serbia, Spain, Sweden, Switzerland). They attributed its rapid long distance dispersal to the transport of infected honey bees by commercial or hobbyist bee keepers.

Since then, Nosema ceranae has been found in Canada (the provinces of Nova Scotia, New Brunswick and Prince Edward Island) and extended its range in the United States (Minnesota) (Williams et al. 2008). It has also been found in Uruguay (Inverrnizzi et al. 2009), Australia (Giersch et al. 2009) and Hungary (Tapaszti et al. 2009).

Temporal Emergence of Nosema ceranae:

Not only does the scientific literature show that Nosema ceranae has become globally distributed, it also shows that it has been infecting Apis mellifera probably since it was first reported in the literature as a parasite of Apis ceranae. Klee et al. (2007) concluded that N. ceranae had jumped to Apis mellifera ‘within the last decade’ (their paper was submitted for publication in October 2006), a finding consistent with the research of Paxton et al. (2007), who reported that Nosema ceranae had been present in Apis mellifera in Europe since at least 1998.

Where it has become established, N. ceranae has gradually displaced N. apis as the most prevalent nosema infection. Martin-Hernandez et al. (2007) found evidence of Nosema ceranae’s growing severity over time in Europe, with the gradual replacement of N. apis by N. ceranae as the most prevalent nosema infection in in bees samples from Spain, Switzerland, France and Germany. Similar results were found in North America by Chen et al. (2008), who reported that N. ceranae had not only been present there for longer than previously thought (since at least 1995), but that by 2007 it was the primary nosema infection of the honey bees they tested.

Experimental Link between Nosema ceranae and CCD

The rapid spread of Nosema ceranae around the globe and its temporal pattern of emergence and intensification coincided with increasing numbers of colony collapses (e.g., Martin-Hernandez et al 2007). Nevertheless, ‘correlation is not causation’, a saying exemplified by the IAPV case above - and further scientific work would be required to establish the cause-effect link between N. ceranae and CCD.

As Klee et al. (2007) remarked, “Analyses of colonies with and without apparent nosema disease combined with experimental infection trials are needed to determine if there is a causal link between Nosema ceranae and colony collapse.” The scientific research into Nosema ceranae gradually provided strong experimental evidence of a cause-link, at least in Europe. Below is a sketch of the key research findings that establish this connection.

First, Fries et al. (2006) confirmed that Nosema ceranae has become established as a naturally recurring and persistent new infection of European honey bees and could no longer be thought of as a sporadic, exotic infection caused only by the importation of bees or bee products.

Second, experimental infection trials demonstrated that not only was Nosema ceranae able to infect and kill Apis mellifera, it was far more pathogenic than its relative Nosema apis (Higes et al. 2007). In fact, it was soon established that the relative risk of bee depopulation observed in colonies with both Nosema species or N. ceranae only was almost 6 times greater than in colonies without such infections (Martin-Hernandez et al. 2007).

Third, Higes et el. (2007) also described a plausible ‘mechanism of collapse’. They found that bees infected with Nosema ceranae died suddenly after a period of infection, which supported a hypothesis that infected bees die away from the hive while foraging, leading to a steady colony depopulation that would only be detected when a hive (i.e. the queen) could not keep up with the disappearance of foragers in the field (i.e. by laying more eggs and producing worker bees). To an observer, say a commercial beekeeper, this would appear to be a sudden loss and thus one of the key symptoms of CCD – colonies found without adult worker bees and no dead bees near the hive.

Fourth, Higes et al. (2008) showed that natural infection of bee colonies by Nosema ceranae could cause colony collapse. Consistent with the hypothesized ‘mechanism of collapse’ of Higes et al. (2007), they found that signs of colony weakness were not observed until the queen could no longer replace the loss of infected worker bees and that the long period asymptomatic N. ceranae infection helped explain the absence of obvious symptoms until colony collapse occurred.

Importantly, Higes et al. (2008) also showed that Nosema ceranae could be isolated from infected bees, used to infect non-infected colonies, that these colonies subsequently collapsed, and that Nosema ceranae could then be isolated from in bees from those colonies. Theses steps follow Koch’s postulates, a key part of the process for establishing a cause-effect link between a candidate pathogen and a disease. The lack of these steps was a key criticism of the conclusions drawn by Cox-Foster et al. (2007) about the link between IAPV and CCD (e.g., Anderson and East 2008).

Fifth and finally, Higes et al. (2009) reported how Nosema ceranae caused colony collapse in two commercial bee operations, the first such case observed under field conditions. In both cases, analyses supported the conclusion that the observed collapse was due to infection by Nosema ceranae. The researchers searched for and did not find other significant pathogens (e.g., IAPV) or pesticides (e.g., neonicotinoids).

The Weight of Scientific Evidence Favours Nosema ceranae over IAPV as a Cause of CCD

The weight of scientific evidence favours Nosema ceranae over IAPV as a cause of CCD. Not only have more scientific papers been published on Nosema ceranae than IAPV (23 vs. 7), but these papers include a series of substantive papers that experimentally establish a causal link between Nosema ceranae and colony collapse in Europe.

This substantive research shows that Nosema ceranae jumped from Apis ceranae, its natural host, to Apis mellifera sometime in the early to mid-1990’s, that it quickly increased its spatial distribution around the world during the same period of time that Europe and other areas in the world saw increasing instances of colony collapse, that it is now a natural pathogen of Apis mellifera, that it is highly pathogenic to Apis mellifera, that experimental infection of Apis mellifera by Nosema ceranae produces colony collapse exhibiting a key symptom of CCD, that this symptom can be accounted for through a plausible biological ‘mechanism of collapse’, and that natural infections cause colony collapse in commercial beekeeping operations under field conditions in the absence of other suspected causes, such IAPV or pesticides.

No comparable body of research exists for IAPV, and in fact scientific support for IAPV as a cause of CCD in the US has recently waned after vanEngelsdorp et al. 2009 failed to replicate the findings of Cox-Foster et al (2007) – that is, IAPV was not correlated with CCD in this new study.

Thus, based on my two performance measures of number of publications and their substantive content, I conclude that there is a greater weight of scientific evidence for Nosema ceranae as a cause of honey bee colony collapse than for IAPV.

There is No Published Evidence that Nosema ceranae causes CCD in the United States

Yet, a problem remains: while scientific support for IAPV as a cause of CCD has declined since 2007, there is currently no published scientific evidence that Nosema ceranae plays a role in CCD in the United States. This could be for several reasons.

First, the early US research into CCD quickly dismissed Nosema ceranae as a culprit after it was not detected at levels considered high enough to cause colony collapse (see Russell 2007 and also Cox-Foster et al. 2007). This could explain why, in their recent Scientific American article about CCD, Cox-Foster and vanEngelsdorp (2009) do not specifically mention of N. ceranae at all, just that two nosema species were found and dismissed as a possible cause of CCD.

This early dismissal of Nosema ceranae by senior and influential researchers may have biased the direction of research and research funding in the US away from N. ceranae and towards IAPV. This may change with more recent US research that found that in some cases N. ceranae was present in levels high enough to cause colony collapse (van Engelsdorp et al. 2009).

Additionally, perhaps the time has come for greater collaboration between European and US scientists on the potential role of Nosema ceranae in North American cases of CCD. It would at least be useful to rule it out through direct experimentation, rather than indirectly through correlation, especially given the substantial scientific support for its role in CCD in Europe.

Second, research on Nosema ceranae in Europe has been going on a lot longer than research on CCD and IAPV in particular, in the North America. The first papers suggesting a role for N. ceranae in colony collapse were published in 2006, based on research completed in 2005 or earlier, while IAPV emerged as a pathogen of concern in 2007. Based on the publication pattern observed for N. ceranae ( 1 paper in 1996, 2 papers in 2006, 5 papers in 2007, 6 papers in 2008, and 8 papers in 2009) perhaps we can expect more substantive papers on the link between IAPV, or some other virus, and CCD over the next few years.

For example, in their recent article in the popular science magazine Scientific American, Cox-Foster and vanEngelsdorp (2009) describe an experiment in which honey bees were experimentally infected with IAPV and then exhibited symptoms consistent with CCD 1-2 weeks later. While this is consistent with the hypothesis that that IAPV causes CCD, they also observed colonies infected with IAPV that did not collapse, and in fact, some of them even managed to rid themselves of the virus. (While this information is interesting, it was not reported in a peer-reviewed journal, thus I did not consider it in the weight of evidence analysis.)

Third, it is important to remember that CCD is not a ‘thing’, but a collection of symptoms. It is possible these symptoms may arise from multiple causes and that CCD in North America may result from a different set of factors than colony collapse in Europe. This ‘multiple factor’ hypothesis is also one of the contenders brought forward during the early days of CCD, and as noted earlier, seems to be where some US researchers are beginning to focus.

In the meantime, the overwhelming weight of scientific evidence for the cause-effect link between Nosema ceranae and colony collapse in Europe, as well as the presence of N. ceranae in North America, supports the adoption of precautionary beekeeping practices. In fact, some professional beekeepers already manage their operations under the assumption that N. ceranae is the primary culprit in colony collapse (Vass 2009).

Next post CCD post: Pesticides and CCD. Cheers.

References for This Post:

Anderson, D. and I.J. East. 2008. The Latest Buzz About Colony Collapse Disorder. Science 8 February 2008: 724c-725c. Letter in response to Cox-Foster et al. 2007.

Blanchard P, Schurr F, Celle O, Cougoule N, Drajnudel P, Thiéry R, Faucon JP, Ribière M. 2008. First detection of Israeli acute paralysis virus (IAPV) in France, a dicistrovirus affecting honeybees (Apis mellifera). Journal of Invertebrate Pathology. July 30, 2008 online

CBC news (April 22, 2009). ``Parasite behind European honeybee colony collapse, researchers say`` (about the Higes et al 2009 paper below)

Cox-Foster, D. and D. vanEngelsdorp. (April 2009). Saving the Honeybee. Scientific American Magazine. See this link – online version: Solving the Mystery of the Vanishing Bees

Cox-Foster, D.L., S. Conlan, E.C. Holmes, G. Palacios, J.D. Evans, N.A. Moran, P. Quan, T. Briese, M. Hornig, D.M. Geiser, V. Martinson, D. vanEngelsdorp, A.L. Kalkstein, A. Drysdale, J. Hui, J. Zhai, L. Cui, S.K. Hutchison, J.F. Simons, M. Egholm, J.S. Pettis and W.I. Lipkin. 2007. A Metagenomic Survey of Microbes in Honey Bee Colony Collapse Disorder. Science 318 (5848): 283 – 287.

Chen, Yanping and J.D. Evans 2007. Historical Presence of Israeli Acute Paralysis Virus in the United States. American Bee Journal (here too)

Chen, Y., J.D. Evans, I.B. Smith and J.S. Pettis. 2008. Nosema ceranae is a long-present and wide-spread microsporidian infection of the European honey bee (Apis mellifera) in the United States. Journal of Invertebrate Pathology 97(2): 186-188.

Fries I., R. Martin, A. Meana, P. Garcia-Palencia, M. Higes. 2006. Natural infections of Nosema ceranae in European honey bees. J Apicult Res 45: 230–233.

Fries, I., F. Feng, A. da Silva, S.B. Slemenda, N.J. Pieniazek. 1996. Nosema ceranae n. sp. (Microsporidia, Nosematidae), Morphological and Molecular Characterization of a Microsporidian Parasite of the Asian Honey bee Apis cerana (Hymenoptera, Apidae). European Journal of Protistology, 32(3): 356-365.

Giersch, T., T. Berg, F. Galea and M. Hornitzky. 2009. Nosema ceranae infects honey bees (Apis mellifera) and contaminates honey in Australia. Apidologie 40 (2009) 117-123

Higes, M., R. Martín-Hernández, E. Garrido-Bailón, A.V. González-Porto, P. García-Palencia, A.Meana, M.J. del Nozal, R. Mayo and J.L. Bernal. 2009. Honeybee colony collapse due to Nosema ceranae in professional apiaries. Environmental Microbiology Reports Volume 1 Issue 2, Pages 110 – 113, Published Online: 16 Feb 2009.

Higes, M., Raquel Martín-Hernández, Cristina Botías, Encarna Garrido Bailón, Amelia V. González-Porto, Laura Barrios, M. Jesús del Nozal, José L. Bernal, Juan J. Jiménez, Pilar García Palencia and Aránzazu Meana. 2008. How natural infection by Nosema ceranae causes honeybee colony collapse. Environmental Microbiology, doi:10.1111/j.1462-2920.2008.01687.x

Higes, M., P. García-Palencia, R. Martín-Hernández and A. Meana. 2007. Experimental infection of Apis mellifera honeybees with Nosema ceranae (Microsporidia). Journal of Invertebrate Pathology 94(3), March 2007, Pages 211-217

Higes, M., R. Martína and A. Meana. 2006. Nosema ceranae, a new microsporidian parasite in honeybees in Europe. Journal of Invertebrate Pathology 92(2): 93-95, June 2006. doi:10.1016/j.jip.2006.02.005

Huang, W., J. Jiang, Y. Chen and C. Wang. 2007. A Nosema ceranae isolate from the honeybee Apis mellifera. Apidologie 38 (2007) 30-37, DOI: 10.1051/apido:2006054

Invernizzi, C. , C. Abud, I.H. Tomasco, J. Harriet, G. Ramallo, J. Campá, H. Katz, G. Gardiol and Y. Mendoza. 2009. Presence of Nosema ceranae in honeybees (Apis mellifera) in Uruguay. Journal of Invertebrate Pathology, 101(2): 150-153, June 2009.

Klee, J., A.M. Besana, E. Genersch, S. Gisder, A. Nanetti, D.Q. Tam, T.X. Chinh, F. Puerta, J.M. Ruz, P. Kryger, D. Message, F. Hatjina, S. Korpela, I. Fries and R.J. Paxton. 2007. Widespread dispersal of the microsporidian Nosema ceranae, an emergent pathogen of the western honey bee, Apis mellifera. Journal of Invertebrate Pathology Volume 96, Issue 1, September 2007, Pages 1-10

Maori, E., N. Paldi, S. Shafir, H. Kalev, E. Tsur, E. Glick and I. Sela. 2009. IAPV, a bee-affecting virus associated with Colony Collapse Disorder can be silenced by dsRNA ingestion. Insect Molecular Biology 18(1): 55 – 60, Published Online: 19 Jan 2009.

Maori, E., S. Lavi, R. Mozes-Koch, Y. Gantman, Y. Peretz, O. Edelbaum, E. Tanne and I. Sela. 2007. Isolation and characterization of Israeli acute paralysis virus, a dicistrovirus affecting honeybees in Israel: evidence for diversity due to intra- and inter-species recombination. J Gen Virol 88 (2007), 3428-3438; DOI 10.1099/vir.0.83284-0.

Martín-Hernández, R., A. Meana, L. Prieto, A.M. Salvador, E. Garrido-Bailón and M. Higes. 2007. Outcome of Colonization of Apis mellifera by Nosema ceranae. Applied and Environmental Microbiology, 73(20): 6331-6338

Paxton, R.J., J. Klee, S. Korpela and I. Fries. 2007. Nosema ceranae has infected Apis mellifera in Europe since at least 1998 and may be more virulent than Nosema apis. Apidologie 38:558-565, DOI: 10.1051/apido:2007037.

Palacios, G. et al. 2008. Genetic Analysis of Israel Acute Paralysis Virus: Distinct Clusters Are Circulating in the United States. Journal of Virology, July 2008, p. 6209-6217, Vol. 82, No. 13 doi:10.1128/JVI.00251-08

Russell, S. (April 25, 2007). “UCSF scientist tracks down suspect in honeybee deaths” San Francisco Chronicle

Tapaszti, Z., P. Forgách, C. Kővágó, L. Békési, T. Bakonyi, M. Rusvai. 2009. First detection and dominance of Nosema ceranae in Hungarian honeybee colonies. Acta Veterinaria Hungarica 57(3): 383-388, September 2009, DOI 10.1556/AVet.57.2009.3.4. Online Date Monday, July 27, 2009

vanEngelsdorp, D., J.D. Evans, C. Saegerman, C. Mullin, E. Haubruge, B.K. Nguyen, M. Frazier, J. Frazier, D. Cox-Foster, Y. Chen, R. Underwood, D.R. Tarpy, J.S. Pettis. 2009. Colony Collapse Disorder: A Descriptive Study. PLoS ONE 4(8): e6481. doi:10.1371/journal.pone.0006481 (Received: March 6, 2009; Accepted: June 29, 2009; Published: August 3, 2009)

Vass, Keith. (July 20, 2009). Bees are back as scientists uncover cause of colony collapse disorder. Saanich News.

Williams, G.R., A.B.A. Shafer, R.E.L. Rogers, D. Shutler and D.T. Stewart. 2008a. First detection of Nosema ceranae, a microsporidian parasite of European honey bees (Apis mellifera), in Canada and central USA. Journal of Invertebrate Pathology 97(2): 189-192 (February 2008), doi:10.1016/j.jip.2007.08.005.

Other IAPV and Nosema ceranae references of interest:

Antúnez, K., R. Martín-Hernández, L. Prieto, A. Meana, P. Zunino and M. Higes. 2009. Immune suppression in the honey bee (Apis mellifera) following infection by Nosema ceranae (Microsporidia). Environmental Microbiology, doi:10.1111/j.1462-2920.2009.01953.x

Cornman, R.S., Y.P. Chen, M.C. Schatz, C. Street, Y. Zhao, B. Desany, M. Egholm, S. Hutchison, J.S.
Pettis, W.I. Lipkin and J.D. Evans. 2009. Genomic Analyses of the Microsporidian Nosema ceranae, an Emergent Pathogen of Honey Bees. PLoS Pathog. 2009 June; 5(6): e1000466. Published online 2009 June 5. doi: 10.1371/journal.ppat.1000466.

Hayley, J. (July 19, 2007). Asian Parasite Killing Western Bees. Planet Ark.

M. Higes, R. Martín-Hernández, P. García-Palencia, P. Marín and A. Meana. 2009. Horizontal transmission of Nosema ceranae (Microsporidia) from worker honeybees to queens (Apis mellifera). Environmental Microbiology Reports, doi:10.1111/j.1758-2229.2009.00052.x.

Higes, M., Raquel Martı´n-Herna´ndez, Encarna Garrido-Bailo´n, Pilar Garcı´a-Palencia, Ara´nzazu Meana. 2008. Detection of infective Nosema ceranae (Microsporidia) spores in corbicular pollen of forager honeybees. Journal of Invertebrate Pathology 97 (2008) 76–78.

Maori, E., Tanne, E. & Sela, I. 2007. Reciprocal sequence exchange between non-retro viruses and hosts leading to the appearance of new host phenotypes. Virology 362, 342–349. {cited by Cox-Foster et al 2007 as paper that says IAPV first reported in 2004}

Maori, E., E. Tanne and I. Sela. 2007. Corrigendum to “Reciprocal sequence exchange between non-retro viruses and hosts leading to the appearance of new host phenotypes” Virology 362: 342–349. Virology 368(1), 10 November 2007, Page 218.

Mayack, C. and D. Naug. 2009. Energetic stress in the honeybee Apis mellifera from Nosema ceranae infection. Journal of Invertebrate Pathology 100(3): 185-188.

Pajuelo, A.G., C. Torres, F.J.O. Bermejo. 2008. Colony losses: A double blind trial on the influence of supplementary protein nutrition and preventative treatment with fumagillin against Nosema ceranae. J Apicult Res 47: 84–86.

Williams, G. R., Michelle A. Sampson, Dave Shutler and Richard E.L. Rogers. 2008. Does fumagillin control the recently detected invasive parasite Nosema ceranae in western honey bees (Apis mellifera)? Journal of Invertebrate Pathology Volume 99, Issue 3, November 2008, Pages 342-344 doi:10.1016/j.jip.2008.04.005

“The copyright of the article ‘Honey Bee Colony Collapse Disorder (CCD) VII: IAPV, Nosema ceranae, and CCD’ on ‘What’s Your Ecotype?’ is owned by Ian Parnell. Permission to republish ‘Honey Bee Colony Collapse Disorder (CCD) VII: IAPV, Nosema ceranae, and CCD’ in print or online must be granted by the author in writing.”

Previous posts about CCD:

Honey Bee Colony Collapse Disorder (CCD) I: Should we really be surprised? (May 28, 2007)

Honey Bee Colony Collapse Disorder (CCD) II: What’s causing it? (May 30, 2007)

Green Grazing: Water, Flying Food, Ground-level Ozone, Farmland Biodiversity and Colony Collapse Disorder (July 28, 2007)

Green Grazing: SUDS, Biodiversity Stuff, More About Bees, African Agriculture, and Satellite Fish (August 2, 2007)

Honey Bee Colony Collapse Disorder (CCD) III: The Power of the Press Release (September 28, 2007)

Honey bee Colony Collapse Disorder (CCD) IV: IAPV, CCD, Australian Bees and the Silence of the Press (March 27, 2008)

Honey Bee Colony Collapse Disorder (CCD) V: Trends in Reporting and Research (June 12, 2009)

Honey Bee Colony Collapse Disorder (CCD) VI: The Global Status of CCD (July 10, 2009).

Honey Bee Colony Collapse Disorder (CCD) VI: The Global Status of CCD

noreply@blogger.com (Ian Parnell) — Sat, 11 Jul 2009 06:07:00 +0000

What is the global status of honey bee Colony Collapse Disorder? Where is it occurring? Is it getting better or worse? Is its range increasing, or decreasing? Such questions might seem easy to answer given the worldwide concern about CCD; however, they turned out to be surprisingly difficult to address.

Using Google and Google Scholar, I searched for quantitative data on honey bee colony losses collected in the context of CCD and that was published in peer reviewed journal papers, association magazines, or industry and government reports.

I found little recent information: three consecutive years of surveys of US beekeepers starting in 2006, one industry summary report from Canada for 2008, and one paper reporting the results of a survey of beekeepers from Turkey in 2007, and the proceedings of a recent (March 2009) conference on colony losses.

The questionnaire-based US surveys specifically track the location, timing, and intensity of winter losses of honey bee colonies and one index of CCD-like losses (dead colonies found in spring with few or no adult bees). In the most recent survey conducted over the winter of 2008/09 total losses were 28.6% while overall CCD-like losses were 15%, much lower than the 60% reported for 2007/08. Unfortunately, the first survey, conducted over the winter of 2006/07, did not report an overall percentage of CCD-like losses.

Outside of the US I only found two reports that provided statistics on winter colony losses: a report on Canadian colony losses for 2007/08 (about 35% over all provinces) and a paper reporting the results of a survey of Turkish beekeepers over the winter of 2006/07 (close to 40% overall). Interestingly, neither source attributed the high reported colony losses to CCD.

The dearth of published data on colony losses may soon be over. I found the proceedings of a conference on honey bee colony losses. It summarizes talks by bee researchers from more than thirty, mostly European, countries. For each country, the researchers discuss data on colony losses and suspected causes. A review of the summaries indicates that CCD is not yet prevalent in Europe. Researchers tend to attribute losses to familiar pests and pathogens and poor management practices.

In summary, the patchwork of published quantitative data does not support a cohesive assessment of the global status of CCD, but does allow these answers to my initial questions: CCD still occurs in the US, it seems to be less intense there this year, and it is not occurring in other countries for which data could be found. Cheers.

References for this post:

Canadian Association of Professional Beekeepers. 2008. CAPA Statement on Honey Bees Losses in Canada (Spring 2008) – Final Revision.

COLOSS 2009. Proceedings of the 4th COLOSS Conference Prevention of honeybee COlony LOSSes in the Faculty of Agriculture University of Zagreb Svetosimunska cesta 25 Zagreb, Croatia March 3-4, 2009.

Giray, T., B. Çakmak, L. Aydin, I. Kandemir, A. Inci, D. Oskay, M. Ali Döke, M. Kence and A. Kence. 2007. Preliminary survey results on 2006-2007 colony losses in Turkey. Uludag Bee Journal August 2007, pp 101-107

vanEngelsdorp, D., J. Hayes, Jr., R.M. Underwood, J. Pettis. 2009a. A Survey of Honey Bee Colony Losses in the U.S., Fall 2007 to Spring 2008. PLoS ONE.

vanEngelsdorp D., J. Hayes, and J Pettis. 2009b. Preliminary Results: A Survey of Honey Bee Colonies Losses in the U.S. Between September 2008 and April 2009. Abstract issued by MAAREC (Mid-Atlantic Apiculture Research and Extension Consortium. (May 19, 2009). {Paper to follow later.}

vanEngelsdorp, D., R. Underwood, D. Caron, J. Hayes, Jr. 2007. An Estimate of Managed Colony Losses in the Winter of 2006 - 2007: A Report Commissioned by the Apiary Inspectors of America. American Bee Journal 147 (7) 599-603.

Previous posts about CCD:

Honey Bee Colony Collapse Disorder (CCD) I: Should we really be surprised? (May 28, 2007)

Honey Bee Colony Collapse Disorder (CCD) II: What’s causing it? (May 30, 2007)

Green Grazing: Water, Flying Food, Ground-level Ozone, Farmland Biodiversity and Colony Collapse Disorder (July 28, 2007)

Green Grazing: SUDS, Biodiversity Stuff, More About Bees, African Agriculture, and Satellite Fish (August 2, 2007)

Honey Bee Colony Collapse Disorder (CCD) III: The Power of the Press Release (September 28, 2007)

Honey bee Colony Collapse Disorder (CCD) IV: IAPV, CCD, Australian Bees and the Silence of the Press (March 27, 2008)

Honey Bee Colony Collapse Disorder (CCD) V: Trends in Reporting and Research (June 12, 2009)

Honey Bee Colony Collapse Disorder (CCD) V: Trends in Reporting and Research

noreply@blogger.com (Ian Parnell) — Sat, 13 Jun 2009 18:38:00 +0000

What ever happened to Colony Collapse Disorder? Since the IAPV breakthrough of 2008 the press has been relatively quiet on this subject. The journalistic stampede that accompanied CCD`s emergence in 2006 has calmed down to an occasional stray article, most of which simply rehash what is already known and reported.

This makes sense when you consider that in some cases it appears the press stampede was driven by press releases from scientific organizations: no breakthroughs = no press releases = no news articles. Nevertheless, while there may be no big news, or at least big press releases, when you dig down, you will find that lots of research is being done as science continues its slow steady pursuit of CCD’s cause. Let’s take a look at some numbers.

The observation that CCD is currently not a hot news item is easy to demonstrate. A search on Google’s News Archive using the phrase ‘colony collapse disorder’ on May 18, 2009 yielded these results, reported as ‘search year (total hits)’:

2005 (0),
2006 (4),
2007(1,680),
2008 (1,150),
2009 (202 to May 18, 2009, linear projection to 534 for whole year).

Clearly, the number of news articles about CCD increased steeply from 2005 to a peak in 2007. Over this period, the press became aware of the CCD phenomenon and scrambled to learn and communicate about it. There was much uncertainty and concern about what was going on. Then, as fresh information became scarce, the number of articles declined dramatically in 2008 (down by 60% from 2007). Projecting from the numbers up to the search date, it looks like barring any major breakthrough the numbers will continue to drop in 2009.

On the other hand, the number of scientific review and research papers related to CCD has increased each year since 2005, as shown by a search on Google Scholar. Using Scholar’s advanced search option and searching on the phrase ‘colony collapse disorder’ ‘anywhere in article’, restricted to the ‘Biology, Life Sciences, and Environmental Sciences’ category yielded these results, reported as ‘search year (total hits, number relevant)’:

2005(7, 0),
2006(1, 0),
2007(36, ~ 25 – mostly general articles outlining the current scientific thinking about CCD, that is, the hypotheses about causative factors),
2008(67 hits, almost all reference the phrase CCD somewhere, many are research papers, also moving into discussions about the need for wild pollinators),
2009 (31 hits up to May 18/09, mostly original research on aspects of CCD, e.g., pathogens and pesticides. Liner projection to 81 publications).

No doubt as more CCD research is published, press releases will stimulate period increase in press coverage. In subsequent posts I will explore the largest blips on the CCD radar the IAPV breakthrough, focusing on three areas: 1) the (relatively) current status of CCD in the US and around the world, 2) the relative roles of suspect pathogens (e.g., IAPV and Nosema ceranea) appear to play in CCD, and 3) and the growing focus on the link between certain classes of systemic pesticides and CCD. Cheers.

Previous posts about CCD:

Honey Bee Colony Collapse Disorder (CCD) I: Should we really be surprised? (May 28, 2007)

Honey Bee Colony Collapse Disorder (CCD) II: What’s causing it? (May 30, 2007)

Green Grazing: Water, Flying Food, Ground-level Ozone, Farmland Biodiversity and Colony Collapse Disorder (July 28, 2007)

Green Grazing: SUDS, Biodiversity Stuff, More About Bees, African Agriculture, and Satellite Fish (August 2, 2007)

Honey Bee Colony Collapse Disorder (CCD) III: The Power of the Press Release (September 28, 2007)

Honey bee Colony Collapse Disorder (CCD) IV: IAPV, CCD, Australian Bees and the Silence of the Press (March 27, 2008).

“The copyright of the article ‘Honey Bee Colony Collapse Disorder (CCD) V: Trends in Reporting and Research’ on ‘What’s Your Ecotype?’ is owned by Ian Parnell. Permission to republish ‘Honey Bee Colony Collapse Disorder (CCD) V: Trends in Reporting and Research’ in print or online must be granted by the author in writing.”

Measuring Environmental Performance: One Number Is Not Enough

noreply@blogger.com (Ian Parnell) — Sun, 07 Jun 2009 18:59:00 +0000

In his article ‘Saving the Planet by Numbers’, David MacKay offers the quantitatively minded enviro-skeptic a new energy standard for comparing the relative performance of green actions and technologies to each other and the status quo. (MacKay, David. (April 23, 2009). “Saving the planet by numbers” BBC News website).

Unfortunately, a single measure of environmental performance usually is not enough to tell the whole story. MacKay proposes a new standard for putting, “. . . green lifestyle ideas under the spotlight.” This standard would measure energies in Kilowatt-hours and how fast activities use or produce energy in Kilowatt-hours per day, or some other unit of time or distance. He provides an overview of how this standard might be used to compare activities and technologies for four categories: ‘Simple Individual Actions’ like you might find on green top-ten lists; ‘Transport’; ‘Heating’; and ‘Decentralized Power Generation’.

For example, under the ‘Transport’ category, MacKay reports that the average fossil-fuelled British car outperforms hydrogen vehicles at 80 KWh/100 km versus 254 KWh/100 km, respectively. He also includes the performance of electric vehicles (6-20 KWh/100 Km) noting that “. . . even if electricity comes from traditional fossil-fuel power stations, electric cars are still more efficient than petrol cars.”

Multiple Measures of Environmental Performance Help Us to Assess Trade-offs Between Alternatives

Unfortunately, a single measure of environmental performance doesn’t tell the whole story. For example, MacKay’s single-number energy standard can’t be used to compare the relative performance of the transport options in terms of reduced emissions of carbon dioxide.

Since we are usually interested in more than one thing when we address environmental concerns, looking at multiple performance measures can provide a clearer picture of the relative tradeoffs inherent to alternative options, transportation-related or otherwise.

Comparing PHEV Impacts Using Ground-Level Ozone Production and Carbon Dioxide Emissions

This is illustrated by the multiple performance measure approach taken in a paper I recently reviewed that used simulation modeling to explore the impact of large-scale use of plug-in hybrid electric vehicles (PHEVs) on air quality: it compared both ground-level ozone production and carbon dioxide emissions across a range of alternative PHEV-use scenarios (see here).

Interestingly, not only did the researchers find that the large-scale use of PHEVs reduced ground-level ozone production, the main focus of their study, but also that carbon dioxide emissions were lower too.

The latter result was somewhat counterintuitive since the virtual PHEVs were charged using electricity from coal-fired generating stations, increasing the greenhouse gas emissions of these facilities above baseline conditions.

The reason was that the large-scale replacement of gasoline-powered vehicles with PHEVs drastically reduced total car-related emissions, more than compensating for the increased emissions from the coal-fired stations.

Multiple Performance Measures Can Also Increase Confidence in Results

This result would have been missed by focusing on ground-level ozone alone as a performance measure. Thus, in this case at least, using multiple performance measures helped build a stronger-case for the expanded use of PHEVs in areas with power-grids fed with electricity from fossil-fuelled generating stations.

My intent here is not to detract from MacKay’s proposed energy standard. It looks like a useful tool for comparing the energy performance of green actions and technologies – in conjunction with other measures. But I think it’s important to remember that environmental choices usually consider, explicitly or implicitly, multiple objectives and values. Focusing too narrowly on a single measure of performance leaves us open to wrongly interpreting results and can also preclude the opportunity to learn. Cheers.

References for this post:
MacKay, David. (April 23, 2009). “Saving the planet by numbers” BBC News website.

“The copyright of the article ‘Do Measuring Environmental Performance: One Number Is Not Enough’ on ‘What’s Your Ecotype?’ is owned by Ian Parnell. Permission to republish ‘Measuring Environmental Performance: One Number Is Not Enough’ in print or online must be granted by the author in writing.”

Washing Our Car With Rain Barrel Water: How Many Buckets?

noreply@blogger.com (Ian Parnell) — Mon, 04 May 2009 00:37:00 +0000

It rained hard last night and our rain barrel was full by morning. Since the garden was nicely watered, I decided to use some of that dewy fresh rain water to wash our car. I wanted to try out something I'd read about being able to wash a car using only two buckets of water. So, I went to the rain barrel and filled up our one bucket for the soapy water and our battered watering can for rinsing . . . then I went back to the rain barrel the watering can several more times (six I think). Turns out I couldn't wash our car using two buckets of water - either it's too big, or the buckets are too small! In the end, I'm not sure I saved much water over just using a hose with a spray gun, but at least it was rain water that would have gone down the drain otherwise. With a little practice, though, I think I'll be able to get it down to maybe three or four cans. We'll see. Cheers.

End of Post

Do Plug-In Hybrid Electric Vehicles (PHEVs) Really Reduce Emissions?

noreply@blogger.com (Ian Parnell) — Sat, 25 Apr 2009 17:11:00 +0000

Plug-in Hybrid Electric Vehicles (PHEVs) are touted as a technology for reducing vehicle related emissions of carbon dioxide and other pollutants that affect human health. However, do they really achieve net improvements in emissions or just shift them from cars to power stations? Recent research has addressed this question, focusing specifically on the potential of PHEVs for improving air quality by reducing emissions of the pollutants that lead to increased low-level ozone concentrations.

Low-Level Ozone is Geographically Localized Problem with Health Implications

Unlike the global problem of stratospheric ozone loss (i.e. the ‘ozone hole’), ground-level ozone is a geographically localized problem arising when sunlight reacts with Volatile Organic Carbons (VOC) and nitrous oxides (NOx). These precursor chemicals occur naturally, but their primary source is the internal combustion engine, a source which ensures the chemicals are especially concentrated near urban centres. High concentrations of these chemicals can create high levels of ground-level ozone, which harms not only human health (see here), but also the yield of agricultural crops (see here).

Reducing Vehicle Emissions Can Lower Low-Level Ozone Concentrations

Fortunately, ground-level ozone is potentially easier to control than stratospheric ozone loss since more local control can be exerted over emissions that create it. Since ground-level ozone is produced by a photochemical reaction between sunlight and some of the chemicals found in car exhaust, the intensity of its production varies by season, time of day and geographic location – factors that affect the how much sunshine and meets how much air pollution. For example, ground-level ozone production is greatest in the summer during the morning hours in areas with lots of traffic (e.g. city centres during the morning rush hour).

For this reason, one way to control ground-level ozone levels is by shifting the timing and intensity of vehicle emissions. This can be done, for example, by prohibiting the use of certain equipment (e.g., lawn mowers) at certain times of the day, or by using tolls or fees to reduce how many cars enter city centres (e.g., London, England).

Another way is to reduce emissions at the source and low-emission vehicles, like PHEV’s can also play an important role. However, it is important to evaluate how and how much such technology can contribute to reducing the problem rather than just assuming it will always help. A question of particular importance is what is the impact on air quality and greenhouse gas emissions of transferring emissions in one sector (on-road vehicles) to emissions in another sector (power plants burning fossil fuels)?

Plug-in Hybrid Electric Vehicles (PHEVs) Reduce Vehicle Emissions and Improve Air Quality

In a recent scientific paper, Thompson et al. (2009) analysed the effectiveness of PHEVs for reducing vehicle-related ozone concentrations. They tested the assumption that charging PHEVs at night with the unused base-load electricity of coal-fired generating stations would lower the diffuse daytime emissions of VOCs, NOx’s from cars enough to offset the increased localized emissions of these pollutants at coal-fired generating stations. They also looked for a net decrease in carbon dioxide emissions.

The researchers based their analysis on a real power-grid covering the N.E. US states of Pennsylvania, New Jersey and Maryland (PJM). They calculated that the ‘excess’ power available at night from the grid’s base-load power plants (largely coal-fired) could support the substitution of 20% of the grid area’s car fleet with PHEVs. This corresponded to roughly a 20% reduction in diffuse vehicle-related emissions during the day and a 20% increase in localized power plant emissions due to coal at night.

The Effect of PHEVs on Air Quality was Evaluated Using a Complex Photochemical Model

The researchers evaluated the impact of these relative changes in vehicle and power plant emissions using historic emissions data for a severe pollution event in August of 2002 in the power-grid area in combination with a sophisticated and complex photochemical model. The model was used to predict the movement of emissions over space and time of air pollutants while accounting for factors that affect the concentration and creation of pollutants like weather conditions, chemical reactions under varying conditions, and the deposition chemicals from air to ground.

The analysis considered four scenarios: 1) a “base case” scenario with the same emission pattern as found for the August 2002 event; 2) an emissions scenario based on the full utilization of PHEVs during the day and then charging them at night using electricity from coal-fired power plants; 3) a less optimistic scenario where emission reductions due to PHEV use were only half of scenario 2; and 4) a scenario where only car emissions changed and there was no increase in the night time emissions from coal-fired power plants. This latter scenario represents increased used of pollution controls for coal-fired plants, or the increased use of alternative non-emitting power sources like wind generation.

The model results for scenario 1, the “base case” scenario, were compared to the actual 2002 data to see how well the model performed and were found to be highly comparable. This provided confidence that the results found under the other three scenarios would follow realistic patterns of behaviour. The results for scenarios 2-4 were then compared to the modelled “base case” results and expressed in terms of changes from the “base case” numbers over a suite of performance measures.

Increased Use of PHEVs Decreased Low-Level Ozone Concentrations and Carbon Dioxide Emissions

The overall results showed that shifting emissions from cars to coal-fired power plants had the potential to significantly reduce ozone levels over most of the power grid area. However, there were also ‘disbenefits’, or worsened conditions in some areas, arising due to the complex chemistry of ozone. Nevertheless, the researchers concluded that increased PHEV use could generally reduce ozone concentrations, especially for cases where PHEVs were charged at night using lower or non-emitting power sources (e.g., wind power, or controlled coal combustion).

Additionally, the results confirmed that using the shift in emissions from cars to power plants did not increase overall carbon dioxide emissions. The additional power generation from the coal-fired power plants led to an increase of about 99,610 tons of carbon dioxide emissions for the grid-area, while the decrease in vehicle related emissions from replacing cars with PHEVs was about 122,670 tons. This is a net reduction in carbon dioxide emissions of about 23,000 tons. Given their analytical assumptions, the researchers cautiously concluded that, at the least, the scenarios they evaluated would not lead to an increase in carbon dioxide emissions.

Thompson et al. (2009) is a Rich Source of Information on Air Quality Science and Regulations

The answer to the question posed at the beginning of this post is thus, “Yes, increased use of PHEVs can lead to a net-reduction in the emissions and improve air quality – most of the time.”

However, this paper is a rich resource for several reasons beyond just answering that question. First, it provides references for quantitative data and regulatory information on emissions science. Secondly, it illustrates how computer modeling is used to explore complex large-scale environmental issues, in this case to better understand how and if proposed regulations and technology can improve air quality. Third, the work is presented in a straightforward way that is accessible to readers interested in the science behind sustainability and green technologies, but without expert training in air quality science. Finally, the results emphasize that ‘sustainability’ is a context-dependent concept; achieving it can depend on your specific objectives as well as how, where and when it is measured - when it comes to living sustainably, details matter.

Related posts: Gasoline vs. Electric Cars

Reference for this post:
Thompson, T., M. Webber, and D.T. Allen . 2009. Air quality impacts of using overnight electricity generation to charge plug-in hybrid electric vehicles for daytime use. Environ. Res. Lett. 4 014002 (12pp) doi: 10.1088/1748-9326/4/1/014002

“The copyright of the article ‘Do Plug-In Hybrid Electric Vehicles (PHEVs) Really Reduce Emissions?’ on ‘What’s Your Ecotype?’ is owned by Ian Parnell. Permission to republish ‘Do Plug-In Hybrid Electric Vehicles (PHEVs) Really Reduce Emissions?’ in print or online must be granted by the author in writing.”