Vermont Center for Ecostudies

Team Berak Finds Reason for Optimism

2014-02-09T21:36:00.000-05:00

Team Berak, 8 February 2014

Jim Goetz, a dedicated team of Haitian conservationists and I just completed 3 days of banding and point counts at our Berak study site, one of the largest broadleaf forest remnants in Haiti's La Visite National Park. As part of a grant-funded project to provide Payments for Ecosystem Services incentives to local tenants in and around Berak, we are documenting the migrant and resident bird population there, following up studies we conducted in 2005. By simultaneously preventing further forest loss and promoting regeneration, we hope to preserve - and increase over time - this vulnerable "island" of critical habitat. A precious reservoir of biodiversity is at stake. I was encouraged to note that Jim's contract with the local tenant who farms Berak appears so far to be viable - no additional cutting had occurred within the forest core since last winter, and some impacted areas are rapidly regenerating.

We ran 18 mist nets and captured nearly 100 individual birds (95 to be exact) at Berak - 13 carried bands from our field visit a year ago, while one tenacious Narrow-billed Tody still sported its band from 2005! Again, as last February, we were surprised to detect no Bicknell's Thrushes (BITH) in this forest patch, despite having mist-netted two birds at our smaller and more highly impacted La Visite site earlier in the week. Berak, which supported at least 7 BITH in 2005 (we banded 6), does not appear to have changed drastically since then, so the species' complete absence during two consecutive years is puzzling.

Mist-netted La Selle Thrush, Berak, Haiti

Banding highlights at Berak included 2 La Selle Thrushes, a striking but endangered endemic Hispaniolan cousin to our American Robin, and a male Sharp-shinned Hawk (the Hispaniolan subspecies is endemic), which we had captured last year. The dawn and dusk chorus of Rufous-throated Solitaires provided a haunting, magical backdrop to our visit.

Although conservation in La Visite (and elsewhere in Haiti) remains fragile, positive signs provide hope that the tide can be turned. The battle is uphill, to be sure, but the cause is worth every effort we can muster.

Chris Rimmer

Our Blog has moved!

2013-10-01T14:21:00.001-04:00

Thanks for following our blog. We've decided to move to Wordpress. Head on over and check out our new blog site. It has the same good stuff, but a lot easier to read!
http://vtecostudies.wordpress.com/

Thanks!

Vermont Atlas of Life Field Day at Marsh-Billings-Rockefeller National Historical Park

2013-09-22T14:32:00.001-04:00

Join us during the Forest Festival Weekend at Marsh-Billings-Rockefeller National Historical Park on Sunday September 29 for a Vermont Atlas of Life Field Day. Learn about nature and how to contribute your own natural history sightings to the project through iNaturalist. Plan on a moderate hike with staff from Vermont Center for Ecostudies. Each program will focus on a particular nature topic and we'll collect data as we go!

Field Trip (meet at the Forest Center):
8:00am Birds
10:30am Trees
1:30pm Bees
4:00pm Monarch Butterflies (no hike)

Songbirds may have “borrowed” DNA to fuel migration

2013-09-22T13:47:00.001-04:00

Myrtle Warbler. Photo by K.P. McFarland

A common songbird may have acquired genes from fellow migrating birds in order to travel greater distances, according to a University of British Columbia study published this week in the journal Evolution.

While most birds either migrate or remain resident in one region, the Audubon’s warbler, with habitat ranging from the Pacific Northwest to Mexico, exhibits different behaviours in different locations. The northern populations breed and migrate south for the winter, while southern populations have a tendency to stay put all year long.

Evolutionary biologists have long been puzzled by research that indicates some Audubon’s warblers share the same mitochondrial DNA (mtDNA) with myrtle warblers – a different species of songbird that migrates annually to the southeastern U.S., Central America and the Caribbean – even though they look dramatically different.

“Mitochondria are only passed down from mothers to their offspring,” says David Toews, a PhD candidate in UBC’s Department of Zoology. “So it’s a very useful marker for differentiating species. In this case, finding two species of songbirds sharing the same mtDNA is very surprising, so we set out to find out why.”

By analyzing genetic data and stable isotopes in feathers, and by measuring oxygen consumption of the mitochondria in their flight muscles, Toews and fellow researcher Milica Mandic pinpointed the precise geographical location near the Utah-Arizona border where the myrtle warblers’ “wanderlust” genes displace the Audubon warbler’s ancestral mitochondria. This region happens to also be the transition zone where we see a change in the migratory behaviour of Audubon’s warblers.

“Because of its prominent role in reconstructing evolutionary relationships, people often forget that mitochondria actually have a very important function as the main energy generator of cells,” says Toews. “Our findings suggest that over generations, the Audubon’s warbler may have co-opted the myrtle’s mitochondria to better power its own travels.”

Source: Univeristy of British Columbia press release

This map from Toews, et al shows the breeding ranges, migratory behaviour and distribution of mitochondrial DNA (mtDNA) in four groups of yellow-rumped warblers. New data from Toews and colleagues demonstrates that the area where there is a transition in mtDNA is also home to a shift in migratory behaviour, from residents to migrants.)

VCE and Birds Brave the Elements on Final 2013 Mansfield Foray

2013-09-20T17:38:00.002-04:00

After nearly two months away from our favorite mountain haunt, VCE staff could hardly resist a final Mt. Mansfield “fix”. A mid-September overnight foray to our long-term ridgeline study plot has become an annual rite of passage, intentionally timed to coincide with the autumnal resurgence of Bicknell’s Thrush activity. Some years, we’ve had remarkably productive mist-netting, and it’s always a delight to be back up there.

This fall, with little latitude in our schedules to wait for optimal weather, four of us ascended the Mansfield toll road in late afternoon on September 13. We hung our hats on a forecast that predicted slowly clearing skies, after several days of cool rains. Above, thick clouds draping the ridgeline provided our first clue of what awaited. We were greeted by hypothermic conditions that precluded any possibility of mist-netting — temperatures in the low 40sF, buffeting winds, and soaking clouds. We struggled with numb fingers to set up 10 nets, hoping (with low confidence) that conditions might improve by daybreak. They didn't, and temperatures had in fact dropped to the high 30s. After our second cup of coffee in the ski patrol hut, we decided to venture up to the ridgeline, arriving ~7:30 am. Winds were a bit lower than during the previous night, and several Bicknell's Thrushes (BITH) were calling, a few even breaking into song.
 

How to weigh a BITH in inclement weather

Knowing this represented our last chance for field work in 2013, we decided to open nets, check them constantly, and try a few playbacks. Surprisingly, we caught a BITH right off the bat, then another, then a Golden-crowned Kinglet, then another BITH, then...the wind dropped slightly and the temp soared to 39F. We managed to keep our 10 nets open until noon, banding inside a cramped but relatively warm Prius. When all was said and done, we had netted 5 BITH — 3 adults (including one male we banded back in June) and 2 immatures. We also banded 2 kinglets, 1 adult Blackpoll and 1 immature Yellow-rumped warbler. Hardly a major haul, but far better than we had expected when peering out the ski patrol hut windows at dawn.

BITH were far and away the most conspicuous birds on the ridgeline, with at least 8 heard. As usual, they proved themselves far more hardy than us humans. Their annual mid-September resurgence of activity is puzzling, but probably related to the fact that many of them will be right back on the ridgeline about 7 months from now. Most will depart for their Greater Antillean wintering grounds during the latter half of September, though a few will linger into early October. Some may well have pushed off with the clearing cold front that passed that very night, within hours after we hightailed it down the mountain.   


Chris Rimmer checking skull pneumatization of a Blackpoll Warbler

A handful each of Yellow-rumped Warblers and Golden-crowned Kinglets completed our avian encounters outside of netting, although a distant raven croaked once or twice. Not a single junco or White-throat was seen or heard. We didn’t manage to attach our 20th and final geolocator to a Blackpoll Warbler (our fingers were too numb to manipulate the unit on our one netted adult!), but the 19 units that we attached to birds in June and July are now collecting data that will yield priceless insights when we retrieve them next spring.

The Flight of the Falcon

2013-09-11T10:44:00.000-04:00

When asked to name the fastest animal on earth, many people will respond “cheetah.” But it is the peregrine falcon – a cliff-dwelling raptor –that holds that title with the ability to reach speeds of 200+ MPH as they stoop (dive) in flight. (The cheetah tops out at a mere 70 MPH). Equally remarkable is the fact that this speed demon of the skies was nearly wiped out 50 years ago; its recovery ranks among the great success stories of conservation biology and endangered species management.

Historically, the eastern peregrine falcon population was centered in New England and the Adirondack Mountains, ranging south along the spine of the Appalachians to western Georgia. In 1940, the population was estimated at 350 pairs; by the mid-1960s, the species was completely gone from the region, a victim of the devastating pesticide DDT. Today, thanks to a highly successful reintroduction and management program, the species has been removed from the federal list of endangered species, though it remains listed as “threatened” in New Hampshire. It was removed from Vermont’s list in 2005.

The road to recovery began in the early 1970s with the establishment of the Environmental Protection Agency, which banned DDT in the U.S. The Endangered Species Act of 1973 provided protection and much-needed funds for a peregrine recovery program. Around the same time, the technique of breeding peregrines in captivity was perfected, providing a source of birds that could be reintroduced into their vacant range.

In New England, approximately 300 captive-bred peregrines were released during the late-1970s and 1980s at 17 different sites in Massachusetts, New Hampshire, Vermont, and Maine. The reintroduced population grew slowly at first: by 1991 there were just 22 nesting pairs. During the last 20 years, however, New England’s peregrines have undergone a population boom, with an estimated 114 breeding pairs fledging 150 young in 2010. In addition, the use of buildings, bridges, quarries, and other human-made structures for nesting is now widespread, especially in urban areas, where the species only infrequently nested prior to reintroduction.

In the early 1990s, I began working with colleagues to place numbered aluminum bands on peregrine falcon chicks’ legs at nest sites across New England, allowing us to identify individual birds should they be encountered later. Through banding, we have gained insights into falcon movements and dispersal patterns, causes of mortality, and survivorship.

Between 1990 and 2009, we banded 986 nestlings in the six New England states. Of those, 238 (24 percent) were encountered at least once after banding. Most were seen in New England, but nearly 25 percent were found outside the region, including in eight eastern states, three Canadian Provinces, and one bird each in Cuba and Nicaragua. The young male found in Cuba had traveled 1,675 miles from its natal site in Acadia, Maine, the bird in Nicaragua had traveled 2,305 miles from its nest site on Mount Horrid in Vermont.

Peregrine Falcon dispersal in New England.

Of the 238 encountered after banding, 50 were re-sighted at breeding territories across the eastern U.S., with the majority of those (39) returning to New England. There was a strong tendency for peregrines to settle at nest sites similar to those on which they were raised (e.g., those hatched on cliffs were more likely to nest on cliffs, while those from urban sites tended to nest on urban structures). However, movement between habitats was also documented.

On average, female peregrines dispersed farther than males with an average dispersal distance of 149 miles, compared to 104 miles for males. Such female-biased dispersal is widespread among birds. Since males must locate and defend a vacant territory, they will presumably have an advantage if they select a site close to “home.”

Our data also revealed that New England peregrines have strong site fidelity to a nest site. Banded birds returned to the same nest for an average of four years, with some staying at the same site up to 11 years. This is not surprising, given that suitable nesting cliffs are relatively rare, and a really good cliff – with multiple ledges to choose from and abundant prey nearby – is worth fighting for. In fact, there have been numerous cases in which resident adult females waged serious battle with intruding peregrines. In at least three of those cases, the resident bird was killed by the female interloper who then took over the nest siteand paired with the resident male, prompting my colleague Tom French to quip to a reporter, “peregrines may mate for life, but they don’t mourn for a moment.”

Twenty years ago few of us could have imagined the success this project would enjoy. Peregrine falcons have reoccupied the majority of their historic breeding sites in New England, as well as many new sites. In fact, it is difficult to predict the region’s current carrying capacity, given the widespread use of human-created habitats for nesting. Yet, in the face of this resounding success, we must all remember that humans wrote this script, and the play’s still unfolding.

-Steve Faccio

Read the scientific paper behind this story at http://www.bioone.org/doi/abs/10.3356/JRR-12-21.1

Red Spruce Makes a Comeback in New England

2013-09-03T11:46:00.000-04:00

In the 1970s, red spruce was the forest equivalent of a canary in the coal mine, signaling that acid rain was damaging forests and that some species, especially red spruce, were particularly sensitive to this human induced damage. In the course of studying the lingering effects of acid rain and whether trees stored less carbon as a result of winter injury, U.S. Forest Service and University of Vermont scientists came up with a surprising result – three decades later, the canary is feeling much better.

Decline in red spruce has been attributed to damage that trees sustain in winter, when foliage predisposed to injury by exposure to acid rain experiences freezing injury and dies. Paul Schaberg, a research plant physiologist with the U.S. Forest Service’s Northern Research Station in Burlington, Vt., and partners studied red spruce trees in Vermont, New Hampshire and Massachusetts. They found that the influence of a single damaging winter injury event in 2003 continued to slow tree growth in New England for 3 years, longer than had been expected, and had a significant impact on carbon storage.

They also found something they did not expect.

“The shocking thing is that these trees are doing remarkably well now,” said Schaberg, a co-author on the study. Researchers found that diameter growth is now the highest ever recorded for red spruce, indicating that it is now growing at levels almost two times the average for the last 100 years, a growth rate never before achieved by the trees examined. “It raises the question ‘why?’” Schaberg said.

The theories that Schaberg and his colleagues are eager to test include whether the red spruce turn-around can be credited to reductions in pollution made possible by the Clean Air Act of 1990, which helped reduce sulfur and nitrogen pollution. Another possibility is that red spruce may be one of nature’s winners in the face of climate change. For red spruce, warmer winters mean less damage to foliage, which limits growth. Questions for future research also include whether the historic growth rate will continue or whether it will plateau.

The rebound in red spruce growth is described in a study co-authored by Schaberg with Alexandra Kosiba, Gary Hawley and Christopher Hansen, all from the University of Vermont. The study, “Quantifying the legacy of foliar winter injury on woody aboveground carbon sequestration of red spruce trees,” was published earlier this year in the journal Forest Ecology and Management and is available online at:http://www.nrs.fs.fed.us/pubs/43459

“Forest Service science was at the forefront in identifying acid rain and its impacts, and it is enormously gratifying to be at the forefront of discovering this amazing turn-around in red spruce growth in New England,” said Michael T. Rains, Director of the Northern Research Station and the Forest Product Laboratory. “Whether this is a success story for pollution control or a developing story about the effects of a changing climate, we are not yet sure."

In addition to finding the surprising rebound in red spruce growth, Schaberg and his colleagues also answered the question they set out to answer – how did the foliar damage associated with the 2003 winter injury affect carbon storage? They found that the winter injury event reduced the growth of red spruce trees for at least 3 years and resulted in cumulative reductions across the landscape equivalent to the carbon produced by burning 280 million gallons of gasoline.

Historically, red spruce has been an important timber species in the United States. While it remains a major commercial species in Canada, in the United States acid rain and land use changes have resulted in the loss of many red spruce trees.

Source: NRS press release

Seeking a Rare and Vulnerable Alpine Gem

2013-09-01T05:58:00.000-04:00

The White Mountain Fritillary on a hiker's boot

There aren’t many species whose entire range can be covered on foot in a single day. There are, however, several such species in the alpine zone of New Hampshire’s White Mountains. Continuing surveys from last summerseveral VCE biologists, including myself, have visited 100+ points in the alpine zone between Mt. Eisenhower and Mt. Adams, searching for the endemic White Mountain Fritillary (Boloria chariclea montinus). Each point was predetermined to be in suitable habitat for this rare and elusive butterfly. With its flight period, and thus the window for fieldwork, only a few weeks long, we were challenged to visit every point twice this season—no easy task, given unpredictable mountain weather and the fact that long hikes and challenging crawls through krummholz are required to reach many points. Obviously a field job in the mountains has its perks too—from breath-taking views, to glimpses of American Pipits, to a newly informed hiker’s expression of joy when an endangered butterfly lands on his boot!

As for the butterflies, good numbers have been seen on the rare days when the sun is shining and winds are minimal. With only a few points still to be surveyed a second time, we have detected fritillaries at 24 points, with at least as many incidental sightings. These data will be used to zero in on the species’ microhabitat preferences and to set a baseline estimate for future studies to monitor population changes in this endemic, state-endangered butterfly. --Spencer Hardy

Seven Days Newspaper Highlights VCE Loon Biologist Eric Hanson

2013-08-28T12:17:00.001-04:00

Eric with 6 loons behind him

I've always said that one reason the loons have been so successful in Vermont in the past decade is the awareness by boaters and lake-users on how to help the loons. It is articles like this that keep that education going. E.H.

Seven Days is distributed weekly throughout northern Vermont and now has an online version. There was one note-taking error by the author in writing "4 loon chicks" instead of "1" in one of shared stories.

Link to story:

Seven Days article on Eric Hanson

Loon Nest-Warning Signs Fundraising Campaign

2013-08-28T11:41:00.000-04:00

A major reason we can now hear loon calls throughout Vermont has been the use of floating nest-warning signs giving loons a quiet spot for nesting on our busy lakes and ponds. These signs have made a huge difference in the recovery of the loon population from less than 10 nesting pairs in the 1980s to over 70 nesting pairs today.

Help us in maintaining and replacing old and damaged nest-warning signs. Using an online fundraising site called “Crowdrise,” you can make a contribution toward new signs for your favorite lake. The average total cost per sign – including materials and construction – is $80. The new signs will have larger lettering and will be easier to read from a distance.

1) Click on any lake below to link to the Crowdrise website.
2) Hit the "donate" button.
3) Make a donation - thank you.

Thanks for helping us continue one of the most important ways we can help our loons.

Eric Hanson, VCE loon biologist

Lake/Ponds with Nest-Warning Signs

Berlin Pond
Brownington Pond
Buck Lake
Center Pond
Chittenden Reservoir
Derby Pond
Lake Dunmore
Echo Lake (Charleston)
Lake Eden
Lake Elligo
Lake Elmore
Ewell Pond
Great Averill Lake
Great Hosmer Pond
Green River Reservoir
Greenwood Lake
Lake Groton
Harvey's Lake
Holland Pond
Island Pond
Joe's Pond
Kent Pond
Kettle Pond
Little Averill Lake
Little Hosmer Pond
Long Pond (Westmore)
Maidstone Lake
Martins Pond
May Pond
Metcalf Pond
Miles Pond
Mirror Lake (No.10 Pond)
Molly's Falls Reservoir
Newark Pond
Nichols Pond
Lake Ninevah

Norton Pond
Osmore Pond
Peacham Pond
Pensioner Pond
Ricker Pond
Lake Seymour
Somerset Reservoir
South Pond (Eden)
Spectacle Pond
Spring Lake
Sunset Lake (Marlboro)
Wolcott Pond
Woodbury Lake
Woodward Reservoir
Zack Woods Pond

"Sanctuary: A Bird Masque" Celebrates 100 Years

2013-08-18T23:00:00.002-04:00

George Rublee as a Great Blue Heron, 1913

Woodstock, VT and Cornish, NH – This year marks the 100th anniversary of "Sanctuary: A Bird Masque", a poetic drama with dance and music written by Cornish, NH Colonist Percy MacKaye and first performed in 1913 at the Meriden Bird Club’s Bird Sanctuary, just north of Cornish. President Woodrow Wilson had his summer White House in Cornish during that period, and his daughters had leading roles in the play. He and Mrs. Wilson attended the performance. This year’s events will take place on August 24 and 25 at 2 pm. The first is on Saturday in Woodstock at Marsh-Billings-Rockefeller National Historical Park, while Sunday's performance will be in Cornish at Saint-Gaudens NHP.

On both days starting at noon, performances will be preceded by exhibits and eBird demonstrations by VCE, and displays by the Vermont Institute of Natural Science, Change the World Kids, and Audubon Vermont. Admission to both performances will be free of charge.  

The Bird Masque was an early example of environmental activism, with a strong message about the protection of birds from needless slaughter. The masque was a success and continued to be performed around the country; it is credited with the creation of more than 100 bird sanctuaries nationally.

Initially, the play was a result of the Meriden Bird Club acquiring land and establishing the first bird sanctuary in the US. The masque’s success also hinged on Meriden itself, through the town’s dedication to protecting birds, testing and building birdhouses, developing types of feed, and involving the entire community. Meriden became widely known as the “Bird Village” and set standards for other communities and bird clubs to model. Vermont’s already established Bird Club and Botanical Club members included Mrs. Franklin Billings and Miss Elizabeth Billings. Bird feeding stations were observed at the Billings Estate in 1906, as mentioned in a Vermont Bird Club Bulletin. Woodstock organized its first local bird club following a lecture by Baynes to the Lucy Mackenzie Humane Society in 1916.

Earnest Harold Baynes (also a Cornish Colonist, naturalist and first General Manager of the Meriden Bird Club) and MacKaye contributed to the larger conservation movement in America during the 19th and 20th centuries through their bird protection efforts. Baynes went on summer long lecture tours talking about birds, the masque and how to organize bird clubs.

MacKaye gave permission for amateur theater groups to perform the Bird Masque which furthered its reach and conservation message both nationally and internationally; it was performed in England and Japan. Efforts in promoting the Bird Masque and its message contributed to passage of the NPS Organic Act in 1916, signed by President Wilson. Wilson also re-signed the Weeks-McLean Law designed to stop commercial market hunting of migratory birds. In 1918 it was renamed The Migratory Bird Treaty Act.

The masque reenactments will feature music originally composed for the play, reproductions of the original costumes and imaginative bird headdresses for the flock of bird dancers. Cast-member (and birder) Hamilton Gillett of Woodstock describes the play as a "fun, celebratory, and very visual piece."
For more information, visit www.nps.gov/saga or www.nps.gov/mabi.

Lake Fairlee Loon Capture Photos

2013-08-13T13:49:00.000-04:00

The saga of loons taking bait and/or fish just caught continued on Lake Fairlee this past weekend. Here are some photos after the capture. Thanks to Chris and Melissa Madden for helping with the capture and Suzy Kerr, Doug Tifft and many others for monitoring the bird and keeping us informed of its whereabouts. Melissa Madden took the photos.

The loon likely had ingested a hook and line but was actually trying to eat a small fish when we found it Sunday night. It could not swallow anything at the time as a large wad of line was lodged in the throat and tightly wound around both the upper and lower mandibles. The bird was weak but feisty, so we banded and released it after removing the line with my surgical paper scissors. If the loon can begin to eat some small fish, it might recover; if not, then its chances are not so good. We at least gave the loon a second chance.

Mansfield Wrap - Where are the Female Blackpolls??

2013-08-07T10:34:00.000-04:00

The late July wrap-up of VCE's 22nd consecutive field season on Mt. Mansfield's ridgeline left us with a disquieting question: where are all the female Blackpoll Warblers?? Their scarcity on our long-term study plot -- the most striking result so far of this year's monitoring -- has us perplexed and concerned. We captured only 3 females, all during the first half of June, a far cry from the 12 we mist netted in 2012. All were new birds (i.e., previously unbanded), and none were recaptured during the season, suggesting that they may not have stayed on our plot to nest.


Sunrise from the Amherst Trail, Mt. Mansfield (photo by S. Faccio)

For context, during the previous 13 summers (2000-2012), our annual mist netting yielded an average of 10.5 female Blackpoll captures, although numbers ranged widely from only 4 birds (2002 and 2004) to 18 in 2009. Removing those two abnormally low years, when our netting effort was less than usual, we captured an average of 11.6 females annually. Given that we ran more nets for more hours this summer than in most any other year, the precipitous drop raises worrisome questions, and begs an explanation.

Interestingly, numbers of male Blackpolls captured on Mansfield this season were above "normal" (an elusive term in biology), with 23 ending up in our mist nets. This number was likely inflated through our use of vocal playbacks to lure birds into nets for geolocator attachment, but most of these were eventually captured passively during the course of the season. For comparison, during 2000-2012, we mist netted an average of 14.1 male Blackpolls annually, adjusted to 15.7 (range 8-22) when discounting the outlier years of 2002 and 2004. Whatever factors accounted for the steep decline in female captures during 2013, males appear not to have been similarly affected.


Steve Faccio and Brendan Collins attaching a geolocator to a male Blackpoll Warbler

What, if anything, happened to females?? Is 2013 an anomaly, a blip on VCE's 22-year radar of monitoring Mansfield's breeding bird populations? We did not see a similar drop in females of other focal species, like Bicknell's Thrush (we mist netted 10 females, and 22 males). Our best guess is that a combination of spring weather events may have hit female Blackpolls when they were particularly vulnerable. First, storms and associated heavy rains in Florida during early May, at about the time when females may have been arriving from South America via the Caribbean, could have taken a toll on some actively migrating birds. More likely, however, are impacts from the dramatic late May snowstorm that surprised us all here in northern New England and New York. Whiteface Mountain in the Adirondacks recorded nearly 3 feet of snow on May 26, while Mt. Mansfield measured >13 inches! This event would have coincided closely with the return of female Blackpolls, and it's no stretch to imagine that some birds simply didn't survive the conditions, having just arrived after a long, arduous northward migration.

Whatever the reason for 2013's drop in female Blackpolls on Mansfield (and we may never know), we can only hope it's not a sign of deeper problems. Blackpoll Warbler is a species of continental conservation concern for groups like Partners in Flight, and VCE's annual monitoring on Mansfield is one of the only projects that tracks this species' breeding population dynamics. We'll know more a year from now, both after another season of monitoring and from recovery of the light-level geolocators we applied to 18 males and 1 female this summer.

Female Blackpoll Warbler with geolocator (photo by K. McFarland)

Encouragingly, we mist-netted two juvenile Blackpolls during our final July session, indicating that the species' nesting season wasn't a total bust. The VCE crew will return to Mansfield for our annual "mop-up" visit in mid-September. We'll hope to find some Blackpolls still present and to attach our one remaining geolocator to an adult before it departs for points far south. We'll report back then, and we expect to have some fascinating insights to share a year from now. Stay tuned.

It’s not always easy (or pleasant) being a loon volunteer

2013-08-02T10:44:00.002-04:00

Two adults fighting. Photo by David Homer

Unlike most other species of wildlife, people can be witness to every aspect of a loon’s daily life from copulation and egg laying to territorial challenges and even death.

Ricker Pond volunteer, Bonnie Flemming-Richardson, recently watched from less than 50 feet away an intruder loon repeatedly attack a 5 week old chick for 20 minutes resulting in the death of the chick. Part of her wanted to interfere, but another side of the brain said to let nature takes its course. The event was traumatic; the attacking loon appeared almost possessed. Bonnie relives the moment constantly since the event happened in mid-July.

The other hard part is that Bonnie and her husband spend lots of time caring for the nesting raft and nest warning signs and then watching the season progress only to lose one chick to another loon. The other chick died the week before likely from a boat hit. Double-whammy. It’s easy to ask oneself, why keep trying.

Chick loss to intruder loons has always been a major source of “natural” mortality. There are indications that intruder loons are having more impacts on nesting success and chick survivorship as the population continues to grow, but it is difficult to quantify. For example, a large adult male loon was killed by another adult in late May on Nelson Pond. But even 20 years ago when there were less than 25 nesting pairs in Vermont, loons killed other loons while vying for a spot in an existing territory despite numerous unoccupied lakes. Successful territories are in high demand, and loons are willing to fight for them rather than start a new territory on a new lake without any established nest sites. Also, not only does winner of the battle win the territory, usually an experienced and successful mate comes with it.

Why kill the chick? If the takeover has already occurred, the chick is not the attacker's offspring. Killing the chick prior to a takeover might make the pair more vulnerable to a successful takeover later that summer or the following spring.

In the big picture, this competition is a good thing because it will help stabilize the population as more of the available territories become occupied. It’s just a darn hard thing to witness. It happens all the time in the animal world but most of it occurs out of sight and therefore out of mind.

Eric Hanson

AMC Releases New Google Earth Application for Northeastern High Elevation Areas

2013-07-29T11:53:00.000-04:00

The Appalachian Mountain Club is pleased to announce the release of a Google Earth application that presents information on high-elevation areas in the northeastern United States, from the Catskills of southern New York to Baxter State Park in northern Maine. The application provides the first broadly available overview of the region’s mountain ecosystems, and may be accessed through AMC’s web site at http://www.outdoors.org/conservation/wind/wind-research.cfm.

The application is part of a broader on-going assessment of the conservation status, condition, and ecological value of the region’s high-elevation areas (defined in this project as those lying above 2700 feet). The information is being developed to help guide future conservation of high-elevation areas across the region and to serve as an initial site screening tool for wind power development. A detailed report on the assessment is in preparation.

High-elevation areas are a limited part of the northeastern landscape but provide critical habitat values and have an important role to play in allowing the region’s ecosystems to adapt to future climate change. They provide the primary habitat for Bicknell’s thrush, one of North America’s rarest and most habitat-limited migratory songbirds, as well as other species of conservation concern. They are also likely to provide refugia for spruce-fir-dependent species in a future warmer climate. These areas have been a target for wind power development, but inappropriately sited wind power projects threaten to degrade this critical habitat. Evaluation, prioritization and conservation of the most important high-elevation areas is an objective of many state and regional wildlife conservation plans.

The application includes data layers on high-elevation areas, conservation lands, development, timber harvesting since 1975, and documented and potential occurrences of subalpine (balsam fir - heartleaved birch) forest. Information available for individual high-elevation areas includes size, maximum elevation, conservation status, the nature of development (if any), the extent of harvesting, the documented presence of rare plant species or natural communities, the proportion of the area in spruce-fir forest, the documented presence of Bicknell's thrush and potential Bicknell's thrush habitat, whether the area is included in a large roadless area, and whether the area includes high priority habitat identified in state wildlife action plans or other sources.

Funding for this project was provided by the Sarah K. de Coizart Article Tenth Perpetual Charitable Trust, the Northeastern States Research Cooperative and the Saving New England's Wildlife Amplification Program of the Open Space Conservancy (an affiliate of the Open Space Institute). Development of this application was made possible by a software grant from the Google Earth Outreach program.

The AMC welcomes comments or questions about this application.

Contact:

David Publicover
Senior Staff Scientist
Appalachian Mountain Club
P.O. Box 298
Gorham, NH 03581dpublicover@outdoors.org

Pesticide claims lives of children in India

2013-07-24T17:09:00.004-04:00

Devastating news came from India last week when 23 children died and several others were hospitalized from acute pesticide poisoning. Their school lunch contained high levels of an insecticide called monocrotophos. According to the World Health Organization, swallowing just 120 milligrams of the insecticide - the weight of about five grains of rice - can be fatal to humans.

VCE documented exposure to the same pesticide in Bobolinks that winter in rice fields in Bolivia, another country that has widely used monocrotophos. Of those birds still able to fly into our nets, 40% were exposed at lethal and sublethal levels of the highly toxic insecticide.

Other victims of monocrotophos: Dickcissels and Swainson's Hawks

As in other countries like India that allow its use, monocrotophos poisons humans as well as wildlife in Bolivia. Hospitals regularly treat farmworkers with symptoms of short- and long-term nerve poisoning. The insecticide is so toxic that companies producing the chemical never even attempted to register the product in the U.S., as it would not have passed EPA standards.

Upon completion of our study on Bobolinks, VCE facilitated meetings with Bolivian chemical import companies and government agencies that resulted in a temporary ban on monocrotophos. However, the ban has ended, and more work is needed to promote alternatives.

A major producer and user of monocrotophos, India was asked by the World Health Organization to ban the insecticide in 2009. But even as the parents grieve their unspeakable losses, there is talk not of a ban, but a tightening of regulations to better control its use and distribution.

More on the poisonings in India

- Rosalind Renfrew

Loonwatch Day 2013 - wind and the missing chick

2013-07-21T11:08:00.000-04:00

As I drove north to the Canadian border and Great Averill Lake and Wallace Pond at 6 a.m., the trees were already swaying along the roadside. It was not looking good for counting loons on big lakes. The water surface was choppy but it was still possible to pick out a loon head bobbing half-way across Great Averill.   However, I was bobbing up and down as much as the loon once I was in my kayak.

On the windward side of the lake, the waters were calmer and I was able to confirm the hatch of one chick from the NW pair. Further south as I zig-zagged back and forth across this 800 acre lake, I came across 4 adults near the Inlet territory where one of the pair was last observed incubating 2 weeks ago. Knowing the hatch should be about now, I kept my eyes open for a "stashed" chick since the pair might be part of that foursome. Sure enough, over at the edge of the nesting bay, I picked out a gray feather ball 10 feet off shore. Most people would miss this if they did not know to look for it. I was glad to find 2 chicks from 2 late nests on this outing.

Loonwatch day results are just coming in now.   It will be interesting to see how the count numbers compare to previous years on the large lakes. Lake Memphremagog had 2-3 foot whitecaps making surveys essentially impossible. Some volunteers have waited for calmer conditions, which is better than no survey or a really poor survey even if the loons fly about some. I'll share results in a few weeks.   Thanks everyone who helped out (or tried).    Eric Hanson

Where Have All the Monarchs Gone?

2013-07-17T17:45:00.001-04:00

Montréal, July 16, 2013 — The first monarch butterflies generally arrive in Québec in mid-June. This year, experts and the many people taking part in citizen science initiatives monitoring monarchs have seen an estimated drop of 90% in the overall monarch population in eastern Canada. A precipitous decline that has never before been documented. Across the continent, scientists and butterfly enthusiasts are worried, and the Montréal Insectarium echoes their questions and concerns: could the migration of monarchs in eastern North America one day disappear altogether?

A few difficult seasons

Each spring after spending the winter in Mexico, Monarchs gradually move northward through the United States and eventually into Québec. In 2012, their reproduction rates fell dramatically throughout their journey, as they were confronted with extreme temperatures, record drought, flowers empty of nectar and a scarcity of their host plant milkweed. For some of the same reasons, their return to Mexico in the fall was no easier. The result? During the winter of 2012-2013, researchers found that the monarchs’ overwintering area covered just 1.19 hectares of forest— 60% less than the previous year’s area, which was already well below the average of 7 hectares. On top of that, spring 2013 was marked by unusually cold temperatures and record rainfall. The monarchs’ ability to reproduce as they headed back north may have been greatly diminished.

The exceptionally good conditions for butterflies, including the monarch, last year in Québec were not sufficient to counter the negative effects observed in populations elsewhere on the continent. The monarch’s current situation is a striking example of the impact climate change can have on biodiversity. Extreme phenomena associated with climate change and the loss of natural habitat are increasingly common. Butterflies are usually “champions” of adaptation, making recent observations all the more troubling. Although populations could potentially stabilize in the future, the teams at the Montréal Space for Life and the Insectarium remain vigilant and will be closely monitoring the progress of the monarch over the coming years. Meanwhile, we can all take concrete action to help monarch butterflies in the way we garden and use technology.

How can you give butterflies a helping hand?

Here are just two simple ways you can contribute to maintaining monarch populations and our understanding of their plight:

1) Create a monarch oasis in your garden or even on your balcony. You will help the monarchs reproduce and build energy stores for their fall migration. Visit http://espacepourlavie.ca/en/monarch-oasis for more information.

2) Share your observations of monarchs on e-Butterfly. The data accumulated will help researchers’ better document the impact of climate change and other potential issues on the butterfly populations. Visit e-Butterfly.org.

Keep your eyes peeled for monarchs and help us keep the migration alive.

Vermont Loon News

2013-07-16T11:42:00.001-04:00

Loonwatch is this Saturday, July 20th

There are still a few key lakes that need volunteers:

Bomoseen

Adult loon with chick
© Elinor Osborn
Sunset (Benson)
Harriman Reservoir
Island
Wallace
Great Averill
Stiles

and possibly:

Mollys Falls
Ewell
Shadow (Concord)
Mollys
Norton
Osmore
Spring
Woodbury.

If you are interested in surveying one of these lakes or ponds, please contact me, ehanson@vtecostudies.org, and I will confirm with you towards the end of the week.

All Loonwatch forms can be found on the VCE website.

Record Nesting Year!

Volunteers and staff have documented a record 79 nest attempts so far this summer. This easily eclipses the previous record of 72 nest attempts in 2010!

To date, 47 pairs have nested successfully, while 12 were unsuccessful. Of these 12 failed nests, 4 may have failed because of the record rainfall, and another might have been abandoned after prolonged exposure to fireworks nearby. From the successful nests, 73 eggs have so far hatched, but 10 chicks disappeared early on, often after intruder loon activity.

Many nests were started late this year, likely because of water level changes and competition with other loons. We're still waiting to see how these late nests fare.

There have been 5 first-time nests documented on Center Pond, Coits Pond, Green River Reservoir - Big Island, Miller Pond, and Neal Pond. Chicks have hatched out for the first time on Lake Elmore, Long Pond (Eden), and Metcalf Pond.

Eric Hanson holds the Bald Pond loon after removing fishing line
©Maree Bushey

Rescues

On July 11th, VCE Intern Lauren Schramm, volunteer Maree Bushey, and I caught and released an adult loon on Bald Hill Pond. The loon was reported to VLRP after it was seen entangled with fishing gear. I never have high expectations that we will be successful, but with a little luck, good lighting by Lauren, and a dive by me to the back of the boat with net outstretched, we were able to capture the bird and cut the loose fishing line free. The 3800-gram loon appeared very healthy overall. We hope that the ingested hook dissolves in its stomach acids and that the rest of the fishing material passes through. The bird is banded so we should be able to follow its progress.

We have been searching and chasing another loon entangled in fishing line on Green River Reservoir for over a month, but with no success yet.

Yankee Magazine Highlights VLRP

A few weeks ago, Craftsbury acquaintance and Yankee Magazine Blog writer Julia Shipley spent a morning with me. Here is her story.

Guides for Lakeshore Owners and Boaters

VLRP, in association with the Vermont Watershed Grant program and the Redducs Family Foundation, has published two brochures:Vermont's Common Loon: A Guide for Lakeshore Owners andVermont's Common Loon: A Guide for Boaters. These educational materials are being displayed in self-serve boxes at most breeding lakes, as well as included in mailings to volunteers, contributors and partners. We are working closely with lake associations and volunteers to distribute the guides to lake shore owners. If you have received the brochures, please take a moment to read through them. They are full of helpful hints on how to live successfully with loons. If you have not received copies and would like them or know of someone who would be interested, please let me know.

Water Draw Down Intervention

After losing its first 2013 nest to flooding on Thurman W. Dix Reservoir near Barre, the pair re-nested at the southern end of the reservoir on the big island. I called the Barre Public Works, a VLRP partner, to let them know and learned they were planning to draw the water down 4-5 feet in the next 1-2 weeks to repair Hurricane Irene damage to the dam. This would likely have left the new nest stranded, so we decided to try to move it onto a raft in two stages. First, Mike and I placed the raft next to shore and lifted the nest bowl onto the platform along with a lot of extra plant material and muck. Later that afternoon, the loon was observed happily incubating the eggs on the raft. So far, so good.

A week later, VLRP intern Lauren Schramm and I moved the cement blocks further out to place the raft in deeper, safer water. Within 30 minutes, the loon was back on the raft sitting on the eggs. Again, so far, so good. By July 8th, two chicks hatched out. Success! With all the rain, the raft actually prevented the nest from flooding a second time and the draw down issue was averted.

Thank you volunteers and supporters. As always, the continued amazing success of Vermont's loon population could not happen without you.

Eric Hanson
VLRP Director

ehanson@vtecostudies.org

Study Reveals Troubling Trends for Common Loon

2013-07-13T19:27:00.001-04:00

Photo by Sue Premo and Phil Etter.

9 July 2013 – The future looks uncertain for one of the most beloved symbols of the Canadian wilderness. Bird Studies Canada’s new report The Canadian Lakes Loon Survey 1981-2012 reveals worrisome trends for the Common Loon, an iconic species. Pollution (in the form of mercury and acid precipitation) is the suspected cause.

Currently Common Loon pairs are successfully producing enough chicks to maintain a stable population. Unfortunately, Bird Studies Canada’s research shows that their reproductive success (defined as the annual number of young raised to six weeks of age) has significantly declined since 1992. And the trends indicate that even worse news may be around the corner. If the current rate of decline continues, Common Loon numbers are expected to begin decreasing within two decades.

“We are approaching the tipping point. Annual reproductive success may soon drop below the minimum level required for these birds to sustain their numbers,” says Bird Studies Canada scientist Dr. Doug Tozer, the lead author of the report. “Because 95% of the world’s Common Loons breed in our country, Canadians have a critical role to play in monitoring and conserving loon populations.”

Mercury and acid precipitation affect lake health and directly impair loon reproductive success. The burning of fossil fuels (e.g., in cars and at coal-fired power plants) causes mercury and acid emissions. From the air, these pollutants make their way into lakes. Common Loons’ high position in the food chain makes them powerful indicators of lake health and especially

pollution levels.

Higher mercury levels make loons slower, and affect their behaviour. Adults with higher mercury spend less time collecting food for chicks and defending breeding territories. Chicks have compromised immune systems and are less able to avoid predators. Meanwhile on lakes with higher acidity, fish are less abundant and loons produce fewer young.

Individuals can make a difference by supporting loon and lake research and conservation, and participating in Bird Studies Canada’s Citizen Science programs. The results also support further action to reduce harmful emissions from combustion of fossil fuels.

Findings are based on three decades of research by Bird Studies Canada scientists and volunteer surveyors. Over 3000 Citizen Scientists and Bird Studies Canada members contributed their time, data, and support to make this research possible. More detailed analysis can be found in the paper Common Loon Reproductive Success in Canada, published this spring in Avian Conservation & Ecology.

Bird Studies Canada’s Canadian Lakes Loon Survey program has been tracking Common Loon reproductive success at the national level for 20 years (and for 32 years in Ontario). Bird Studies Canada advances the understanding, appreciation, and conservation of wild birds and their habitats. BSC is Canada’s national charity for bird research and conservation.

Source: Bird Studies Canada press release

The Backcountry Road of Undercarriage Doom, and other Mountain Birdwatch adventures

2013-07-09T18:00:00.000-04:00

The roads got rougher and narrower as we drove through the Vermont backcountry. “It’s a shortcut,” I told Mountain Birdwatch intern Laura Tobin. “I don’t usually go this way, but the GPS insists we take this route.” Bushes stretched their scratchy branches into the road, clutching at the sides of my Honda Accord. Abandoned backhoes and giant tractors gaped from dirt mounds dotting the forest. I tried not to wince as scraping sounds announced the presence of rocks grazing my low-clearance vehicle. Finally, the road ended at a tiny gap in the forest, a two-rut track overgrown with tall grasses and littered with fallen branches snaking off into the dark. The GPS urged us on. I believe at this point there were some choice words directed sharply at the GPS.

Laura and I were heading to Battell Mountain, embarking on my annual Mountain Birdwatch training pilgrimage to our two routes along the Long Trail in the Bread Loaf Wilderness. A few of our survey stations on this mountain are dripping with Bicknell’s Thrush, and each year since 2010

"You can almost never see a Bicknell's Thrush!"

I have taken the Mountain Birdwatch technicians and interns to this site to learn the survey protocols, practice cone counts, and experience a few pre-dawn starts before the season begins in earnest. Each year, Bicknell’s Thrush has offered a special surprise during our visit to this amazing site. In 2011, I had just finished telling my 4 technicians that we almost never see Bicknell’s Thrush, since the short, dense fir in which they breed make them almost impossible to spot. Rounding a corner, the entire group caught sight of a male Bicknell’s Thrush, perched atop a lone snag, singing his heart out, offering us unimpeded views for almost 10 minutes. Last year, during our first survey of the morning, four Bicknell’s Thrush engaged in a vigorous dispute, flying in and out of the vegetation, often whizzing right over our heads, and producing their entire repertoire of songs and calls.

Uniting People and Science for Conservation- In the Parking Lot!

Deciding to forego the Backcountry Road of Undercarriage Doom, the rest of our drive along well-established highways and county roads was uneventful. We pulled into the parking lot for the Skylight Pond Trail, joining three other cars in the lot, and we assembled our packs, poles, hats, and bug spray near the car. Suddenly, from behind me, I heard a surprised and somewhat tentative voice say, “Judith?” I turned to see Mountain Birdwatch volunteer Chris Runcie getting out of her car a few feet away; she and her husband Jim had arrived at Battell Mountain to survey their own Mountain Birdwatch route, Battell Mountain South! Despite a season full of moose sightings, bird song, morning sunrises, and glorious mountain hikes, my most joyous moment this field season was this one- uniting people and science for conservation, right there in the parking lot.

Laura celebrates sunset over the Adirondacks

The Runcies got a head start, hiking up ahead of us, and Laura and I followed behind, listening to the suite of songs change as we ascended; Black-throated Green Warblers and Ovenbirds in the lower-elevation hardwoods, shifting to White-throated Sparrows and Winter Wrens at higher elevation, and finally hearing the piercing song of a Blackpoll Warbler once we entered the spruce-fir forest. No Bicknell’s Thrush, though. We scouted the Battell Mountain North route, finding our first three survey stations and conducting cone counts at each point.

Volunteers Chris, Jim, and Maggie Runcie- Maggie isn't allowed to help with the point counts!

We visited the western-facing lookout rock that spawned several generations of Mountain Birdwatch photographs, enjoying views over Lake Champlain and across to the Adirondacks. Reuniting with the Runcies at the camping area, we cooked dinner together and chatted until dusk. Finally, painfully aware that our 3:45 start was much closer than we’d like, we adjourned to our separate tents. As the rustling of clothes, sleeping bags, and tent zippers died down, the evening chorus began- and a fluty, nasal, and wholly beautiful song emerged out of the semi-darkness. Bicknell’s Thrush, performing right in our campground.

In the dark, from three separate tents, three hushed voices simultaneously breathed, “Yay.”

-Posted by Judith Scarl, who is done with field work for the season and now enjoys a nice comfortable bed on a regular basis

First Vermont Atlas of Life Field Day July 20th

2013-07-09T15:28:00.003-04:00

Flowers, trees, amphibians, butterflies, oh my! Step outside and start recording the fascinating world around you, and share your observations with a growing network of "citizen scientists." Curiosity required, no experience necessary. All programs are free of charge and begin at the Forest Center at the Marsh-Billings-Rockefeller NHP. Parking is available at the Billings Farm & Museum on Old River Road in Woodstock. From the Billings Farm & Museum parking lot, cross Rt. 12 to the park, turn right and take the carriage road into the woods to the Forest Center. 

These family-friendly events are organized by the Vermont Center for Ecostudies and feature walks into the Park and demonstrations of how to contribute data to the Vermont Atlas of Life. Bring a smartphone or digital camera if you have one. Load the free app and register for an iNaturalist - Vermont Atlas of Life account beforehand or we can help you get one so you can start contributing your observations. If you have a smartphone, come with the handy data collection app on it.

iPhone app: https://itunes.apple.com/us/app/inaturalist/id421397028?mt=8

Android app: https://play.google.com/store/apps/details?id=org.inaturalist.android 

Come to any or all of the scheduled programs. We will cap off the day with an evening celebration of National Moth Week. Stick around after the final program for a chance to find some of these nighttime residents.

Schedule 

July 20th

Natural History Walks and Surveys

8:00 AM Vermont eBird
10:00 AM General Natural History Survey
12:00 PM Bumblebees
1:00 PM Plants
8:00 PM Moths

iNaturalist Workshops:
2:00 PM
4:00 PM
8:00 PM

Follow this link to connect to the Marsh-Billings-Rockefeller NHP data center on iNaturalist and the Vermont Atlas of Life!

Butterfly Endurance

2013-07-07T17:07:00.002-04:00

With the temperature in the 80s yesterday, I may have overdone it on my mountain bike. I climbed hill after hill giddy with the adrenaline of the previous downhill thrill. Today, my legs feel like they are filled with lead. Athletics have a way of showing your age, but I was heartened to learn that I wasn’t alone.

It turns out that butterflies have the same age old problem. In 2009 scientists in Sweden reported that the flight endurance of a small butterfly called the Green-veined White decreased with age. The Green-veined White (Pieris napi) is found across Europe and Asia, including the Indian subcontinent. Some scientists believe that the Mustard White, a woodland dependent species found here in the Northeast, is a subspecies of Pieris napi while while most now align it as its own species, Pieris oleracea. Either way, they are very closely related and look quite alike.

How do you test endurance in a butterfly? The scientists released individual butterflies 6 feet in the air and when they landed, they were prodded to fly again and again and again until they were unable to fly due to exhaustion. A simple stop watch yielded the total flight time. They tested three age groups that were raised in captivity. One group was kept in cages for 10 days and another was kept in the cages for 5 days. The third group was 1-day-old butterflies newly emerged from the chrysalis and roaring to go. These butterflies probably only have an average adult life span of about two weeks.

It didn’t matter if they were male or female, young and middle-aged butterflies performed about the same. But by the time the butterflies were 10 days old they were over the athletic hill. I guess I must be about 7 in butterfly age. I just can’t keep up with the newly emerged anymore. I’ll have to ride more wisely.

From the blog, One Square Meter, K.P. McFarland

Source: ÅHMAN, M. and KARLSSON, B. (2009), Flight endurance in relation to adult age in the green-veined white butterfly Pieris napi. Ecological Entomology, 34: 783–787. doi: 10.1111/j.1365-2311.2009.01126.x

Bicknell's and Blackpoll Musings from Mt. Mansfield

2013-07-01T15:33:00.000-04:00

One of 2013's better views of the Mansfield summit (K.P. McFarland)

We've had it all on VCE's Mt. Mansfield ridgeline study site this season - from harsh winds and hypothermic temperatures to soaking rains and violent thunderstorms. Thankfully, we've managed to squeeze in several days of field work, continuing our long-term banding operation and conducting point counts. Results at the midway point of our 2013 season may not be definitive, but they are, as always, illuminating.

So far, it appears to be a fairly "typical" season for our focal species, Bicknell's Thrush (BITH). Numbers of vocalizing birds on and around our roughly 40-acre study plot are similar to those of recent years, with 15-20 sounding off on the dusk chorus. After four evening-morning banding sessions, our number of mist-netted individuals stands at 21 -- 9 of them (7 males, 2 females) new (i.e., previously unbanded) birds, and 12 (9 males, 3 females) returnees from a previous year. The grand dame was a female banded as a yearling in 2009, making her now a 5 year-old: we captured her twice in 2009, missed her entirely in 2010, caught her twice in 2011 (including in mid-September), and netted her once last June 28. While a mere babe in comparison to our record 11 year-old male from Stratton Mountain and the three 10 year-olds we've recaptured on Mansfield during the past decade, this female's five years of survival is no mean feat.

Other returning BITH of note so far are two males that we banded as young-of-the-year on September 13, 2011, and then recaptured multiple times last June. In general, relatively few locally-hatched BITH return to either our Mansfield or Stratton study sites, while both adult males and females show annual site fidelity of 60-65%. We believe that dispersal of young birds is important to ensure genetic mixing among the naturally fragmented mountaintop breeding populations of this rare, vulnerable, and possibly declining songbird.

Male Blackpoll Warbler with geolocator (Chuck Gangas)

We're paying special attention to Blackpoll Warblers this year, as we spearhead an innovative effort to attach light-level geolocators to 20 males. This diminutive songster, weighing only 11-12 grams, has long been believed to undergo one of the planet's most spectacular long-distance migrations, striking out each autumn from coastal areas of New England on a non-stop, transoceanic flight to northern South America. However, questions have recently arisen about whether this awe-inspiring feat is typical for the species, or whether some Blackpoll Warblers follow a route that includes stopovers in places like the Caribbean islands. The miniaturization of geolocators now allows us to gain insights on this intriguing phenomenon. As of the end of June, we have attached 0.4-gram backpack geolocators to 13 male Blackpolls, including two birds that we banded in 2009 and have recaptured every season since. We're confident of affixing all 20 units by mid-July, and we'll eagerly await their return a year from now!

As our Mansfield field season #22 winds down over the next two weeks, we anticipate our nets beginning to fill with fledglings. Despite persistently challenging weather (admittedly, more for us researchers than the birds), we anticipate a strong nesting season, as red squirrels and other mammalian predators are all but absent from montane forests, following last fall's scarce cone crop. Singing will soon begin to wane as adults of all species concentrate on raising their young to independence and begin their annual flight feather molt. We'll share our final results and insights next month.

Flower Trap

2013-07-01T13:45:00.001-04:00

With its foot stuck in a milkweed flower like a Chinese finger trap, the European Skipper was struggling to free itself. On another flower nearby only a leg remained from a previous struggle. Survey enough milkweed flowers and eventually you’ll find a few dead insects, usually small species, left dangling from a leg or two.

They are not a carnivorous plant; trapping and death are just an accident. Instead, milkweed has solved the problem of pollination in a unique manner. There are five pinkish hoods with horns where the nectar is located. Milkweed produces copious amounts of sweet smelling nectar in the hoods to attract insect pollinators. Between each of the hoods is a dark spot with a long slit leading down from it. With most of the flowers in the umbel hanging downward, these slits are a natural place for insects to grab with their feet while syphoning nectar upside-down. Unlike most flowers, milkweeds don’t produce tiny grains of pollen to be carried away piece by piece. Instead, the flower produces sticky, orange packets of pollen, called pollinia, which are designed to stick to an insect’s leg. In each of the five slits are two pollinia waiting to be accidentally snagged and carried off.

In order for an insect to pick up one of the pollinia from a milkweed flower, its leg has to slip into a tiny slit between the anthers along the side of the flower. As the insect struggles to pull its leg back out of that tiny opening, it might emerge with a pollinia or two stuck to it. If the insect is too small or too weak, the only way it can escape the flowers grip is to leave its leg behind. Worker bumblebees, much smaller than spring queens, that forage on milkweed often are missing a claw or leg part.

If the flower is lucky, the insect will travel to another milkweed flower in search of nectar and deliver the pollinia. To do this successfully, they must again pass their leg through one of the anther slits in another flower and have the pollinia come into contact with a very small area at the base of the stigma lobe. There’s a cost to the insect for this delivery service. Bumblebees with pollinia attached forage about 25 percent more slowly. The odds for successful pollination are slim. Seed set in milkweeds is often quite low with only a flower or two in the entire umbel producing seed. But a few flowers are enough to produce clouds of drifting seeds each autumn to sow a new generation in some far off field.

European Skipper resting on grass blades with milkweed pollinia stuck to several legs.

Can you spot the lost leg among the Common Milkweed flowers?

Source: One Square Meter