Search and Serendipity

Something solid

David J. Ringer — Sun, 25 Apr 2010 04:15:09 +0000

MOBILE, ALA. — False expectations, when one has traveled too much and too fast, flicker readily across the consciousness: Toucanets could emerge from the mist. That stub should hold a treeswift. Am I looking for king parrots? Sights, smells, emotions trigger these strange moments. But other moments — the immediate and the real — are the ones that ground the self in time and in place.

An Eastern Kingbird, having just survived a nonstop flight across the Gulf of Mexico, rests a few yards behind the dune line on Dauphin Island, Alabama:

We interrupt this program…

David J. Ringer — Thu, 18 Feb 2010 01:13:57 +0000

VICKSBURG, MISS. — The laptop that has powered Search and Serendipity for almost three years has died, apparently of massive hardware failure. I suspect the motherboard but will never know for sure. It hasn’t been the best of laptops, but it traveled with me to many strange and wonderful places. I guess that’s all over now. Not that I’m sentimental.

The good news is that no important data is lost. The failure has been in progress for about two weeks, so I’ve had ample warning (and frustration).

The bad news is that my blogging schedule will continue to be disrupted for several more days at least.

I am writing this post on the WordPress app for iPhone. I’d been looking for a chance to try it out, but this is an unfortunate way to do it (much better to have been in some exotic locale uploading a photo of a rarity…).

While I’m dealing with this, head on over to 10,000 Birds, where Mike has posted Renato’s video of a hummingbird we saw in Ecuador. It’s awesome because the gorgeous little bird is bathing in puddle on a large leaf, but we are also requesting ID help. Which hummer is it?

OK, I guess now I have no excuses to put off that housework I’ve been avoiding….

Purple Martins in snow and 100,000 blackbirds

David J. Ringer — Mon, 15 Feb 2010 06:50:15 +0000

VICKSBURG, MISS. — Whew, lots going on and a failing laptop on top of everything, so we’re going to cover a lot of ground in this post. Still have heaps of Ecuador photos to share, and more systematics and ID posts in the hopper.

Purple Martins return

I spotted my first Purple Martin of the spring out my bedroom window one week ago — Sunday, Feb. 7. We saw one at the Audubon office on Tuesday, and on Thursday evening, when we returned from Little Rock (that’s another story), a female appeared to have taken up residence in one of our gourds.

SNOW

Friday, it snowed in Vicksburg. We got about 6 inches, which I’m told is the most that’s fallen here in several years. It was a beautiful wet snow that stuck to everything and transformed my “backyard.” I don’t know when or if I’ll see this again here.

Great Backyard Bird Count

Friday also kicked off the Great Backyard Bird Count, so I started counting in the snow. This year, in addition to submitting checklists, I’m also helping out as a reviewer for the state of Louisiana. When reports get flagged by the eBird filters, I follow up on them, contacting the observers for further information if needed.

Northern Cardinal has been the most frequently reported bird on the Great Backyard Bird Count for the last five years. It looks like it’ll claim the title again this year. How cool is it that one of our most frequently encountered birds is also so gorgeous?

Have you ever seen a Purple Martin in the snow? I did on Friday, and here are the (blurry) photos to prove it:

By mid-afternoon, the sun was peeking out, and the snow had already started melting.

While I was on a conference call, I noticed something unusual swimming past with the usual assortment of feral ducks and geese that I see every day. It was a Greater White-fronted Goose (Anser albifrons)! I managed to snap a couple of photos without dropping my phone. After this brief appearance, I never saw the bird again.

100,000 blackbirds

Saturday, I went to count birds at Mahannah Wildlife Management Area in southern Issaquena County. I had good numbers of Canvasback, White Ibis, and sparrows, and I saw three Common Yellowthroats, which was good.

But the real spectacle began as the sun started to set.

I heard the distant clamor of blackbirds and finally spotted a river of Common Grackles up high, moving south. Thousands of birds streamed past — and that was only the beginning. They kept coming. Thousands became tens of thousands, and somewhere along the way, the Red-winged Blackbirds started pouring toward me as well.

The grackles moved high in long ribbons that, at times, stretched farther than I could see in both directions. One such stream passed overhead continually for 20 minutes. The red-wings were much lower, flying in wide bands and in a slightly different direction. Vertigo gripped me briefly as the birds rushed past.

By the time it was done, I’d estimated totals of 75,000 Common Grackles and 30,000 Red-winged Blackbirds — a staggering figure, and one that, so far, gives Valley Park, Mississippi, (the nearest town) more individual birds than anywhere else on the continent in this year’s GBBC.

I couldn’t even begin to hint at the magnitude of the event with my camera, but here are some shots anyway.

My crude colored lines indicate about 50 grackles each. There are about 650 grackles in this image, and it’s just one small section of a stream that passed overhead for several minutes.

OK, you have to see this big to get it, and then you can see a cloud of grackles in the sky, a small, loose flock of red-wings lower down, and thousands of birds packed into the lower tier of trees.

Rusty Blackbird

I got some birding in on Sunday too — four checklists in fact — and was please to hear mockingbirds, cardinals, and House Finches singing. It was almost 60 degrees, and all our beautiful snow is gone already.

I had lots of pelicans and 3,000 Double-crested Cormorants at Eagle Lake north of Vicksburg, and there were a few Rusty Blackbirds feeding on wet ground near the parking lot at the public boat ramp.

One more day

The Great Backyard Bird Count runs through Monday, so you have one more chance to participate!

First day of spring 2010!

David J. Ringer — Thu, 04 Feb 2010 02:23:34 +0000

VICKSBURG, MISS. — At the risk of angering my friends in more northerly latitudes, I’m once again celebrating the first day of spring on the first cross-quarter day — the day halfway between December’s solstice and March’s equinox. This year, that’s today, February 3. It’s spring!

Most of us in the United States regard the vernal equinox (March 20, 2010) as the first day of spring, but various cultures throughout time have celebrated season’s beginnings on the cross-quarter days (this is the origin of Groundhog Day, Celtic Imbolc, and Japanese Setsubun), and in the southeastern United States, I think this makes a good deal of biological sense. Plants come to life and birds begin returning in February; by the time the vernal equinox comes, many of the southern breeding warblers will already be singing on territory.

Exposed surfaces carried a light frost this morning, but I went out early, hunting for signs of spring. At Vicksburg National Military Park, Tufted Titmice were singing persistently — a new development! And something caught my eye in the grasses:

A minuscule Tiny Bluet (Houstonia pusilla, also called Hedyotis crassifolia) reaches for the sun, its face drenched in sparkling dew. It’s the first native wildflower I’ve found in bloom this year.

The birds — Hermit Thrush, Eastern Phoebe, White-throated Sparrow — were still the birds of winter, but songs from titmice and even once from a chickadee told me that something is stirring within them. And though the Purple Martin houses at my office remained empty today, we are expecting martins back any day.

The forest still sleeps, but it is on the verge of waking.

So how about you? Do you see any signs of spring? Or are you siding with Punxsutawney Phil and bundling up for six more weeks of winter?

Great Sapphirewing, Pterophanes cyanopterus

David J. Ringer — Sun, 31 Jan 2010 23:42:07 +0000

VICKSBURG, MISS. — Today’s Ecuador feature highlights the Great Sapphirewings we encountered at Yanacocha Reserve near Quito.

At 6 inches long (or more than seven if you include its bill), the Great Sapphirewing (Pterophanes cyanopterus) is one of the largest hummingbirds in the world. It is larger than all of the other hummingbirds in its habitat and many other species as well, including flowerpiercers, conebills, and chat-tyrants.

The sapphirewing’s scientific name, Pterophanes cyanopterus, is derived from Greek words combined to mean “bright wing” and “blue wing.”

Pinkish-brown underparts identify this bird as a female. When sapphirewings hover, their wingbeats are so slow that they look like large moths fluttering.

This post is part of a series on Ecuador and was included in Bird Photography Weekly #75.

Mexican Ducks are not Mallards … probably

David J. Ringer — Sat, 30 Jan 2010 19:59:45 +0000

Mexican Duck by Pablo Lèautaud

VICKSBURG, MISS. — Version 2.3 of the IOC World Bird List came out last month, and the most interesting change for North American birders is probably the resplitting of Mexican Duck (Anas diazi) from Mallard (Anas platyrhynchos).

The Mexican Duck is resident from southern Texas, New Mexico, and Arizona south through northern and central Mexico. It is essentially non-migratory. Like the Mottled Duck of the Gulf Coast and the American Black Duck of northeastern North America, the Mexican Duck lacks the brightly colored male breeding plumage of the familiar Mallard; both sexes are mottled brown throughout their lives.

Hybrid swarm?

The Mexican Duck has been considered both a full species and a subspecies of Mallard since its formal scientific description in the 1880s. In 1983, the American Ornithologists’ Union lumped it with the Mallard and has left it there ever since, writing in the 1998 seventh edition of its North American checklist that “extensive hybridization in southeastern Arizona, southern New Mexico, and west-central Texas compels merger into a single species (Hubbard 1977).”

The study cited to back up that action was “The Biological and Taxonomic Status of the Mexican Duck” by John P. Hubbard, published by the New Mexico Department of Game and Fish. This study relied on physical characteristics to determine which birds were “hybrids.” Essentially, sets of criteria were established for “pure” Mexican Duck and for Mallard, and birds showing a combination of the features were ruled hybrids. The study concluded that most “Mexican” Ducks occurring in the United States are in fact hybrids and that therefore, the taxon does not deserve recognition as a species under the biological species concept. This analysis became the conventional wisdom and has been parroted ever since.

But it’s bunk. In short, there isn’t much evidence that there is massive, ongoing hybridization between Mallard and Mexican Duck. In a very interesting article, Richard E. Webster writes: “My recent experience in eastern Cochise County [Arizona] and environs is not of the ‘extensive’ hybridization that influenced the decision to lump the two. Rather, it is of no obvious hybridization, because I have not seen an obvious Mallard during the breeding season in the areas I bird, areas in which Mexican Ducks breed at a number of localities in small to moderate numbers.” He goes on to cite studies from the 1980s questioning the “hybrid swarm” theory, breeding bird survey data, and information about breeding biology, all of which seem to contradict the idea that Mexican Duck is being hybridized into oblivion. Apparently no satisfactory genetic studies, which could shed some light on the situation, have ever been done.

What is a Mallard?

The familiar sexually dimorphic Mallard has 10-15 very close relatives around the world, all of which are monomorphic (i.e., lacking a male breeding plumage). Many waterfowl species are capable of interbreeding and producing fertile offspring — even across generic lines — but the situation with the Mallard and its relatives is especially confusing. Interbreeding is rampant under certain conditions; for example, introduced Mallards and indigenous Pacific Black (“Grey”) Ducks (Anas superciliosa superciliosa) have mixed to such an extent in New Zealand that “pure” Grey Ducks are now quite rare.

In North America, Mallards also interbreed with American Black Ducks to a significant degree, but the AOU has always upheld the latter as a valid species.

Kissing cousins?

Two main hypotheses attempt to explain the origins of the Mallard and its closest relatives:

A sexually dimorphic duck, probably rather like the green-headed Mallard of today, was ancestral to the whole clade. Under this scenario, the green-headed Mallard spread out around the world, and various populations began splitting off from it and losing the alternate male plumage, becoming monomorphic. This model can be used to argue that because all the monomorphic forms descended from a dimorphic ancestor, the speciation process did not complete before the populations started coming back into contact again (often due to the activities of humans). Thus, it’s not a stretch to lump them back together.
A monomorphic ancestor gave rise to all or most modern Mallard relatives. Under this scenario, the dimorphic green-headed Mallard is a novelty within the clade. This model can be used to argue that a monomorphic ancestor reached North America and diverged into three populations: American Black Duck, Mexican Duck, and Mottled Duck. Then the green-headed Mallard secondarily invaded North America, coming into contact with the other three populations.

Obviously, if the second hypothesis is closer to the truth, it’s problematic (but not impossible) to treat the Mexican Duck a subspecies of Mallard.

This, in essence, is the argument the IOC uses in resplitting Mexican Duck, citing a 2001 study of Mottled Duck and its relatives:

McCracken et al. (2001) challenged the subspecies status of the Mexican Duck. They found that the Mexican Duck is the southwestern sister “species” of the Mottled Duck and in turn the American Black Duck, all members of a set of original and monomorphic “mallards” that speciated in North America before dimorphic “greenhead” Mallards expanded their range from Europe to North America. They are all closely related members of a recent allopatric radiation with no postzygotic barriers to gene exchange between them. However, they mate assortatively, and do not interbreed freely. McCracken et al (2001) therefore recommended that “Mottled ducks and Mexican ducks be designated as species so that the nomenclature is consistent with phylogeny.” (The Mexican Duck)

Looking closer

The 2001 study is fascinating and well worth a read (link below). Each Mallard carries one of two different genetic signatures in a certain region of its mitochondrial DNA. (Remember that mitochondrial DNA is passed directly from a female to her offspring without recombination.) The trick is that though the Mallard population carries both signatures, the Mottled, Black, and Mexican ducks sampled have only one: type B of the haplotype in question.

McCracken et al. suggest that this pattern was best explained by an invasion of green-headed Mallards into North America. Still able to interbreed with their New World cousins, they would have picked up the mitochondrial genes of the three monochromatic species by crossing with local females, and so the Mallard population would end up with both genetic signatures.

However, the authors note that this hypothesis could be called into question if the type B haplotype were discovered in Mallards in Asia.

So they studied the Mallards in Alaska and the Old World and in 2005 published a paper showing high percentages of type Bs in Alaska but virtually none in Asia and Europe (with one caveat), supporting the idea that Mallards picked up the type B haplotype when they reached the New World. But the high percentage of type Bs in Alaska (far away from the current breeding ranges of any North American monochromatic species) and a confusing result centered around a population of Eastern Spot-billed Ducks in northeast Asia still leave questions open:

In summary, existing data do not support a single explanation for paraphyly of mtDNA haplotypes in Mallards. Instead, a combination of evolutionary processes, including historical and contemporary range expansion, hybridization, and incomplete lineage sorting have likely shaped the current distribution mtDNA haplotype lineages in Mallards and closely related species inhabiting both Asia and North America. Kulikova et al. 2005

To split or not to split?

Despite unanswered questions, the best available evidence indicates that North America’s three monochromatic populations (Mexican, Mottled, Black) did not split off from green-headed Mallards but instead came into contact with that taxon later, and that gene flow then ensued.

This means that treating Mexican Duck as a subspecies of Mallard while elevating American Black Duck and Mottled Duck is probably inconsistent. I say “probably” because paraphyly — reticulation — does happen, so it’s conceivable for populations A and B to diverge, for C to then diverge from B, and then for A and B to remain compatible and even come back together, leaving C a distinct population.

However, it’s not at all clear that this is what has happened or is happening in this case.

But another potential problem is that significant genetic work has never been done on the Mexican Duck; the 2001 McCracken study sampled only four Mexican Ducks from one location in San Luis Potosí.

I can understand why bodies like the AOU might want further clarity in what’s obviously a very complex situation before making a change, but it seems pretty clear that leaving Mexican Duck lumped with Mallard does not reflect the best available information on the complex. Treating the Mexican Duck as a valid species — for now — is a good move by the IOC.

References

American Ornithologists’ Union (AOU) (1998): Check-list of North American Birds (7th edition). American Ornithologists’ Union, Washington, DC.

IOC (2009): The Mexican Duck.

Kulikova, Irina V.; Drovetski, S.V.; Gibson, D.D.; Harrigan, R.J.; Rohwer, S.; Sorenson, Michael D.; Winker, K.; Zhuravlev, Yury N. & McCracken, Kevin G. (2005): Phylogeography of the Mallard (Anas platyrhynchos): Hybridization, dispersal, and lineage sorting contribute to complex geographic structure. Auk 122 (3): 949-965. PDF

McCracken, Kevin G.; Johnson, William P. & Sheldon, Frederick H. (2001): Molecular population genetics, phylogeography, and conservation biology of the mottled duck (Anas fulvigula). Conservation Genetics 2 (2): 87–102. PDF

Webster, Richard E.: The Status of Mottled Duck (Anas fulvigula) in Arizona. Arizona Field Ornithologists.

Trying something new with images

David J. Ringer — Sat, 30 Jan 2010 07:38:34 +0000

VICKSBURG, MISS. — I’ve been storing my images in a Gallery installation for quite some time, but I’ve decided to experiment with the built-in WordPress functionality. I’ve just converted my Sword-billed Hummingbird post to the new system. When you click on a picture, you’ll be taken to a page with a larger version and (bonus!) a comment box. I’m not finished with (or committed to) the process, so let me know if you have any comments. One thing that seems to be missing is the ability to tag photos. Has anyone figured this out?

Update: So far so good. I found a plugin called Media Tags to handle tagging. Not as ideal as having native support, but it works for now.

Also, if you want your picture to appear in the comments, all you have to do is create an avatar linked to your email address with Gravatar. Otherwise, you get a pretty geometric design (an improvement, I hope, over the bland gray figure).

Sword-billed Hummingbird, Ensifera ensifera

David J. Ringer — Fri, 29 Jan 2010 05:10:32 +0000

VICKSBURG, MISS. — At middle elevations in the northern Andes Mountains lives a hummingbird with a bill so spectacularly elongated that it sets its owner apart from all other birds. The Sword-billed Hummingbird (Ensifera ensifera) is the only bird with a bill longer than the rest of its body.

A female Sword-billed Hummingbird. Sword-bills (whose genus and species name, ensifera, means “sword-bearing” in scholarly Latin) have bills 3 1/2 to 4 inches long, which is wildly disproportionate to the rest of their skeletons.

A male.

Sword-billed Hummingbirds and plants with long, tubular flowers like this Passiflora (passionflower) have a special relationship. Sword-bills are the only birds that can reach nectar deep inside the corollas, and in the process of doing that, they transfer pollen from flower to flower. (Can anyone identify this Passiflora to species? I gather it’s difficult.)

And of course, the birds’ tongues are even longer!

All this specialized equipment makes sword-bills look awkwardly spectacular at feeders designed for much smaller birds. Sword-billed Hummingbirds can have bills four inches long, but North American Ruby-throated Hummingbirds are only about 3 1/2 inches in total length including bill and tail!

Check out those pink toes and long black claws.

All pictures taken at Yanacocha and Guango Lodge in Ecuador. This is part two of a series on Ecuador. See more: Pululahua 2010.

Ecuador will blow your mind

David J. Ringer — Thu, 28 Jan 2010 03:58:59 +0000

VICKSBURG, MISS. — I returned this morning from a whirlwind trip to Ecuador. It’s going to take weeks to relate in words and pictures what we encountered in four very full days, so although I’m exhausted, we’d better get started.

This Velvet-purple Coronet (Boissonneaua jardini) — one of about 30 hummingbird species we encountered — is, believe it or not, showing only some of its breathtaking colors in this shot.

I must first thank my hosts, Renato Espinoza and Paola Cevallos of Pululahua Hostal, for their invitation, company, and care. They love their country and its birds and are passionate about seeing them preserved. We’ll find out more about them later.

Seeing representatives of different bird families is exciting to me, so I thought I’d give a tiny taste of what’s to come by showing photos of birds in families I hadn’t encountered before. We’ll start with a real bang (and if you want to hear more about all these birds and many, many more, this would be a really good time to subscribe to my feed or sign up to receive posts by email):

Thinocoridae: Rufous-bellied Seedsnipe, Attagis gayi. Yes, yes, yes!

Capitonidae: Red-headed Barbet, Eubucco bourcierii. This is a female.

Semnornithidae: Toucan-Barbet, Semnornis ramphastinus.

Grallariidae: Yellow-breasted Antpitta, Grallaria flavotincta.

Cotingidae: Olivaceous Piha, Snowornis cryptolophus.

Pipridae: Club-winged Manakin, Machaeropterus deliciosus.

And we’ll close for now with this acrobatic Sapphire-vented Puffleg, Eriocnemis luciani.

¡Voy a Ecuador!

David J. Ringer — Thu, 21 Jan 2010 03:34:14 +0000

Sword-billed Hummingbird by kookr

VICKSBURG, MISS. — You see a brightly colored bird. The colors and patterns are impossible — but you’re trying hard to memorize them (blue crown? auriculars? green?) so you can put a name to the fantastical bird when you get back to your field guide.

It’s a dream. We all have them.

Either that, or you’re getting ready for a trip to Ecuador.

In my case, happily, it’s the latter! Mike Bergin and I have been invited to spend four glorious days birding in Ecuador as guests of Renato Espinoza and Paola Cevallos, owners of Pululahua Hostal.

In terms of species diversity, South America is the planet’s birdiest continent, and Ecuador is the birdiest of them all. For its size, its avifauna is staggeringly speciose; the list exceeds 1600 species. Peru, Colombia, and Brazil all have more species, but they are also many times the size of Ecuador.

There’s no way for me to learn all the species we may encounter before we go, so we’re going to try the immersion approach. And if I drown in a sea of tanagers, hummingbirds, tapaculos, and tinamous, well … there are far worse fates indeed.