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Last night I had the rare opportunity to watch Chimney Swifts come in to their evening roost. They’ve provided me with another wildlife mystery, however. Their roost is somewhere on top of a high rise dormitory on the OSU campus, and there ain’t no chimneys up there.

Chimney Swifts are fascinating creatures. Most closely related to hummingbirds, swifts may spend more time on the wing than any other birds. I’ve read that swifts eat, drink, mate, and even sleep on the wing. If that last one is true, then they must get a lot out of little power naps!

Chimney Swift portrait, Powdermill Nature Reserve

Most folks are familiar with swifts - they are pretty conspicuous - but they’re probably often mistaken for swallows or bats. Some folks get the chance to experience swifts up close and personal: occasionally, babies will fall from their chimney nests and be found clinging to the side of a homeowner’s fireplace. But most of us know them simply as twittering little black boomerangs strung through cigars that can do about Mach 3 in a straightaway.

They fly more slowly when coming to roost. Last night right at 9 pm when the full, red moon had just risen in the east, I noticed our resident flock of about 50 swifts circling and twittering over the roof of Kerr Hall. I had seen them do this before, so I figured they must be roosting somewhere on the roof of that building. The roof, however, is flat, and there are no chimneys.

As the minutes passed and the birds continued circling, the little black shapes became harder to discern against the darkening sky. The first stars blinked on around 9:10. Finally, I thought I had an idea where the birds were going, so I posted myself at the best vantage I could find. There! One at a time, birds were dropping from the wheeling flock, holding their stiff wings aloft, and floating like butterflies in an irregular path to their roost. By 9:16, the twittering fell silent as the last swift wafted down into the roost.

My next assignment? Convince the maintenance crew of a college dormitory to let me climb out onto the roof of their 11-story building and try to figure out where these little guys are roosting.

For more information about swifts, check here.

Another sad environmental disaster in the making was reported here today. Blue Crabs, this generation’s Chesapeake mainstay, are in a population tailspin thanks to water pollution in the Bay and overharvesting by watermen.

Again, as a society, we refuse to learn a lesson. Overharvesting destroyed the oyster stocks in the Chesapeake Bay, and they’ve never recovered. People sounded the alarm about Blue Crabs many years ago, and not enough was done. In fact, the same issues of declines in “submerged aquatic vegetation” that were discussed decades ago in reference to waterfowl populations are affecting crabs today.

If you’ve ever considered an environmentalist an “alarmist”, then this message is for you: listen to them and take heed! This is the kind of stuff they raise alarms about. (1) Population of something declines. (2) Scientists point out that human activities are the likely cause of the decline. (3) Activists take up the mantle to try to motivate society to fix the problem. (4) Society ignores activists. (5) Population declines continue; whatever economic features are linked to the species in question begin to suffer. (6) Industry collapses as resource base diminishes. (7) Society questions if there might be a problem.

We’re at stage 7 with Blue Crabs in the Chesapeake Bay. (We’re somewhere between 4 and 5 on global warming.)

The Great Auk was a large, flightless seabird from the North Atlantic that was hunted to extinction in 1844. The birds were easy to exploit from their remote nesting colonies, where sailors were said to sometimes simply herd the live birds up gangplanks and into their boats. The birds provided a source of fresh meat on long voyages, and were a welcome relief from hard tack. The large eggs were also collected for food, and auk down provided insulation. Once humans developed the ability to reliably sail to nesting colonies of Great Auks, the species was headed down the all-too-familiar path of exploitation that leads to extinction.

Their superficial resemblance to penguins is a wonderful example of convergent evolution, i.e., unrelated species developing through natural selection similar strategies to solve similar problems. In this case, both penguins (order Sphenisciformes) and auks or alcids (order Charadriiformes - this includes auks as well as terns, gulls, plovers, and sandpipers) have evolved the ability to swim rapidly and at depth in ocean water to pursue fish. Through convergent evolution, both groups have developed thick, torpedo-shaped bodies, dense plumage for warmth in cold climates, countershaded coloration (dark above and white below), and reduced wings that can assist in swimming by flapping underwater.

A closer look, however, reveals important differences. For example, auks possess clearly webbed feet, and these probably provide a good deal of propulsion during swimming. The heavy, club-like feet of penguins are generally not used during swimming, as propulsion comes mainly from the flipper-like wings. A penguin’s wings are in fact so modified as flippers for swimming, that they are stiff and bladelike, having lost the ability to fold against the body as do the wings of most other birds. Auk wings are different, in fact all 22 living species are able fliers while all penguins are flightless. Finally, these two groups of seabirds are separated geographically: all auks occur exclusively in the Northern Hemisphere (principally in the far north) and penguins are confined to the Southern (except of course, for the Galapagos Penguin, whose distribution straddles the Equator).

To further add to the confusion between penguins and auks, the word “penguin” is thought to derive from “pinioned” or “pin-winged”. When sailors first encountered the flightless Great Auk with its reduced wings, they described it as a bird who’d had its wings clipped to keep it from flying away. As more and more Europeans explored the southern oceans , they encountered there many black and white “pinioned” seabirds, and they referred to them as they did to the Great Auk - “penguins.” So penguins actually get that name from the history of sailors encountering the flightless Great Auk, and unrelated species from an entirely different hemisphere. Now you know.

But I digress . . .

The reason I’m posting about Great Auks today is that I encountered one recently. Well, sort of, but I was wrong.

While enjoying a great visit with old chum Greg Keller now at Gordon College in Massachusetts, Greg indicated that he had something really cool to show me - something he inherited as part of the College’s natural history collection.

He produced a leaded glass box containing several old eggs.

Only one, that of a Mute Swan, was labeled. The others were fairly easy to identify as ostrich, emu, and rhea, but the last two seemed a bit more interesting. One was not much larger than a chicken egg, and it had a buffy-olive color. Would an oologist from the 19th century have included the egg of a Rhode Island Red in a prized collection like this? It didn’t make sense. Then it hit me - tinamou! Tinamous are roughly chicken-sized and shaped birds from Central and South America that are most closely related to the rheas, ostriches, and emus. Tinamou eggs are beautifully glossy, and this would really have been a treasured specimen for an egg collector.

But the egg that really captured our attention was different. It was an obvious charadriiform egg, based on its pyriform shape and the pattern of uneven dark blotches on a light background. It was however, huge - almost as big as the emu egg in the box. Greg had done some background research based on his hunch that the egg in question was actually that of a Great Auk. All evidence pointed to that being the case. If authentic, this would be the rediscovery of a currently uncatalogued specimen of an extinct species, and a priceless find. It was a thrilling item to behold.

Emu egg (L) and Great Auk egg (R)

Alas, Greg finally had the chance to travel to the Museum of Comparative Zoology at Harvard University, and direct comparison with known eggs confirmed his nagging suspicion that the Great Auk egg in his possession is, in fact, a well-crafted replica.

While our hopes of having encountered a piece of an extinct creature were dashed, I find myself perhaps even more interested in the mystery. Who made this egg, and why? Was there money to be had in producing egg forgeries during the height of the egg collection fad of the 19th century? Was this an honestly produced replica used for display while its authentic antecedent was kept in a more secure location? Had the original owner of the egg been the craftsman who produced it, or had he himself been duped into thinking it was authentic? Where one mystery ends, a new one begins . . .

From overhunting and egg collecting, through the atrocities of the millinery trade and the unintended long-term consequences of DDT, from the introduction of exotic invasive species to nesting sites formerly free of predators and loss of critical nesting habitat from coastal development and the operation of off-road vehicles, from oil spills and inshore water pollution and overfishing, and on through the effects of changing ocean currents and rising sea levels . . .

coastal seabirds are in long-term population decline.

Some of the best studied mixed species colonies in Scotland are apparently in the midst of 15 years of poor reproductive success and colony abandonment. Traditional breeding sites that formerly supported thousands of pairs of various species are now just shadows of their former glory, or have been abandoned altogether. If this was just a Scottish problem it’d be bad enough, but stories like this have been the norm from different regions of the globe for many years. While many seabirds benefit from relatively long lifespans (> 15 years) and populations can generally withstand a few bad years in a row, 15 bad years indicates that something unusual is happening.

In the midst of banding waterthrushes last week, we also had the good fortune of catching a couple of other beautiful birds. The first was the Eastern Phoebe, a species that shares riparian forests with waterthrushes. Phoebes advertise their presence early in the spring with their harsh, grating “song” - “FEE-bee! Fee=brrrrrt!” Holding one in the hand reminds me why we call them “tyrant” flycatchers.

Then, after we had decided to make tracks, we went to collect one of the nets and found a female Black-and-White Warbler waiting for us. These little sprites feed like woodpeckers by gleaning prey from bark, but nest like ovenbirds, on the ground in the leaf litter. The male’s song sounds like a squeaky wheel: “wee-see-wee-see-wee-see . . . “

The Louisiana Waterthrush (pinnacle of avian evolution) nest we found last week fledged three youngin’s yesterday - there was one unhatched egg left in the nest. With a great deal of luck (and a little skill) we were able to capture and band both parents and all three fledglings on the same day.

The nest was in a stream bank on an intermittent tributary to a somewhat larger intermittent tributary. We placed two nets across two of these reaches, each about 15m from the nest itself. The trick is to get the adults bringing food to the nest or leaving to get more food after a delivery. They visit the nest with beakfuls of stonefly and mayfly larvae, tadpoles, water spiders, etc., about every 10 minutes. When the get close to the nest they run along the ground, so nets set too close to the nest will never catch the adults.

The nest site - follow the trail of leaves.

The parents were wary while feeding, as a few crows were hanging around in the treetops. Eventually, though, we nabbed the female. Later we pulled the fledglings from the nest to band them and then tried (in vain) to get them to stay back in the nest when we were done. We got the male a little while later by playing a couple of bursts of waterthrush song.

beautiful female waterthrush

female’s brood patch - area of dropped feathers from the breast that aids in heat transfer to eggs and young during incubation and brooding.

lousy picture of squirmy fledgling

portrait of a haggard waterthrush father - worn out by fledgling care and territory defense

I’ve been informally studying waterthrushes in Oklahoma for a few years now. It looks as though their breeding densities in cross timbers forests are comparable to those of Appalachian forests in the core of their range. Yesterday’s banding effort could help me establish information related to site fidelity - to what degree do the adult birds return to the same territories to breed in subsequent years? Also, philopatry (the return of fledglings to their natal area) is of interest to me. Finally, banding can help me establish age structures - banding has revealed some individuals of this species live in excess of 10 years in the wild!

As something of a sasquatch aficionado, I’m fairly well versed on the folklore of hairy wild men from different parts of the world. Though they go by different names, the general theme of a hairy, bipedal, giant, wildman/ape that lives in the thickest, wildest, most remote corners of our world is a fixture in North America, South America, Russia, China, Tibet, Nepal, Indonesia - even Australia. We rarely, however, gain a glimpse into the mythology of such a creature from the Indian subcontinent, so I was pleased to find this story posted today.

The “mande barung” is India’s wild man, a denizen of the thickest jungle and nearly inaccessible canyons of the Northeast. It is said to be large and heavily built. It is shy and avoids human contact, although it occasionally leaves large footprints behind to betray its presence. The locals know all about it, and have shared their stories of encounters with these creatures for centuries.

Sound familiar? This description could just as easily be applied to Australia’s “Yowie,” China’s “Yeren,” Nepal’s “Yeti,” or Canada’s “Sasquatch.” There’s one more thing mande barung shares with these others: there is not a scrap of indisputable physical evidence that they exist at all.

Stories are great, and evidence that can’t be easily ascribed to a known source keeps me interested and hopeful that spectacular creatures like this do still exist out there. But I ain’t holding my breath . . .

A new study (also here) published in the Proceedings of the National Academy of Sciences provides perhaps the most compelling evidence yet for something those of us with brains have known all along: if you’re gay, you were born that way.

Apparently, relatively simple brain scans reveal that the two hemispheres of the brain are roughly the same size in heterosexual women and gay men. The same comparative technique indicates that heterosexual men and lesbian women share an asymmetric morphology, with the right hemisphere the larger. The research also pointed to similar patterns in the amygdala, with more connections to the right hemisphere in straight men and gay women, and more connections to the left in straight women and gay men.

So, how much more evidence do we need? When will people in this country wake up to the FACT of important biological bases for homosexuality? To discriminate against our gay and lesbian brothers and sisters is akin to discrimination against people for any other genetic nonconformity, and it’s an affront to the principles of equality on which this nation was founded.

There are plenty of reasons for me not to like cross timbers forest. It’s hot out here in the summer, and the ticks can be pretty bad. To combat them, I wear long-sleeved shirts and long pants with rubber boots. Then I duct tape the boots to my pants. I also tend to carry more water. which just weighs me down even more.

In most of these forests, fire suppression has allowed eastern redcedar to proliferate beneath the canopy of oaks, so there is a frequent impenetrable gauntlet of interlocking cedar boughs blocking your way. Where there isn’t cedar, there is greenbriar, hooking your ankles and puncturing your thighs. It seems sometimes that every step takes extra effort. Oh for the soft crunch of leaves underfoot and the occasional downed log on which to rest!

But the cross timbers’ patchwork of oaks and prairies also holds delights that have taken hold of me. I once came upon a nestling chuck-will’s widow in a cross timbers patch. I’ve seen a young black snake rattle its tail in the leaves to mimic the sound of an angry rattlesnake. I’ve bonded with a foraging armadillo on a warm December day.

Last week, I spent a delightful morning in the cross timbers. I knew it would be a good day when we found this tarantula in the road nearby our survey site:

Then this dickcissel sang his prairie serenade (such as it is) for (or rather, “in spite of”) us:

Finally, I had the great luck of finding two nests in the span of just a few minutes. The first belonged to a Bewick’s Wren, and it was the first nest of that species I’ve ever discovered. Next, I was thrilled to locate a nest of Louisiana Waterthrush - the pinnacle of avian evolution. Here’s the mother sitting tight:

So if you’re willing to brave some heat and ticks and greenbrier, wonders await you in the cross timbers.

Found and interesting article here on the influence of climate change on populations of rare birds.

I’ve been thinking too narrowly about this issue. Here in the States, we primarily worry about the timing of migrations as a result of a rapidly warming planet. Will long distance migrants (whose flights are largely triggered by changes in apparent daylength) begin to miss out on locally abundant foods that had previously served as important sources of fuel for migration? Next on my list of concerns might be seabirds whose main source of food relies on upwellings of nutrients in the oceans. Will changing ocean temperatures alter those upwellings, either shutting them down or shifting them away from key nesting areas? Will rising sea levels leave beach-nesting birds with no place to nest?

But the potential impacts of climate change extend even further than these examples. According to the 2008 IUCN Bird Red List, populations of birds the world over are suffering due to ramifications of rapid climate change from global warming. As is so often the case, interacting influences muddy the waters of clear causes, while they exacerbate the detrimental effects.

A great example is the `Akeke`e, a Hawaiian honeycreeper.

Jim Denny photo.

These birds occur only on Kaua`i where they nest in high elevation wet forests. Apparently, recent weather patterns in the Hawaiian Islands have made these forests so wet that many nests are being flooded in the pounding rains. The birds are also susceptible to exotic, invasive mosquitoes that spread avian malaria - previously unknown on the islands. In response to pressure from the mosquitoes, the birds moved higher and higher up the mountains where the chilly air was a barrier to the little bloodsuckers. But recent temperature increases have modified those high elevation temperatures, and the mosquitoes are colonizing the higher elevations as well.

So the problem isn’t so much the warming temperatures, it’s the fact that we’ve introduced the dang mosquitoes. Same with the seabirds. Losing beach nesting areas wouldn’t be such a huge deal if we hadn’t already robbed the birds of 90% of their former habitat by building condos on the beaches. While we’re arguing over how best to combat global warming, it seems to me that we should redouble our efforts to protect and restore habitats.