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There is a dispassionate way to think of the Red Knot, the robin-sized shorebird which flocks to the Delaware Bay every year in May and June on the way to its Arctic breeding grounds. If your concern is correctly identifying it, you could look in your eastern Peterson guide (Fifth edition) and read about how it looks during the breeding season: “Face and underparts pale robin red; back mottled with black, gray, and russet.” In case you weren’t sure that you were in Red Knot habitat, you could check your Peterson guide for that, too: “Sandy beaches, mudflats, tidal flats and shores; breeds on tundra.” If you wanted to delve a little deeper, your Peterson would tell you that the knot is a “well-studied species that has very specific stopping spots for feeding and staging during migration.”
Very specific stopping spots? This is not an overstatement. Let’s say you’re not a birder, but a member of the rufa subspecies of the Red Knot, the particular variety of knot that flies up the Atlantic coast (destination: Arctic tundra) as spring unfolds each year. Most likely you winter in the Southern Hemisphere, in Tierra del Fuego, with about 15,000 of your fellows, although you might be part of a 50 percent smaller population which shares a stretch of beach in northern Brazil at Maranhao, or a member of a yet smaller group on Florida’s Gulf Coast or the relatively short Georgia shoreline.
It’s been a tough winter as you search for your usual food, hard-shelled bivalves (such as the blue mussel), along South American beaches often favored by people on vacation. You may find yourself near offshore oil rigs which have been known to spill their black muck into the very water you rely on to yield sustenance. If you’re wintering in the southeastern U.S., you face similar challenges. But spring approaches and it’s time to move north over thousands of miles to your chief re-fueling stop before hitting Canada’s Hudson Bay and beyond, and you can’t wait. The Delaware Bay beckons, with its feast of tiny, translucent eggs laid by dull-brown, prehistoric arthropods called horseshoe crabs. These creatures are shaped like a shallow helmet and about the size of one, too. Their other notable feature is a long, narrow, dark tail that tapers to a sharp point. When the crabs come ashore to mate and lay their millions of eggs, they will seem to fairly cover the Bay beaches they favor (rough ocean-side waves would just wash the eggs out to sea).
What’s the big deal about the unimpressive-looking beads of fat and energy laid by the crabs? You, the Red Knot, have to eat enough of these so that, over the course of a couple of weeks between May and early June, you can reach a weight of at least 180 grams. If you do, you will have the fortitude to continue on to the Arctic and breed successfully. Although, admittedly, you usually consume hard-shelled bivalves, your digestive tract has shrunk over the long migration leaving you unable to digest anything but soft, puny horseshoe crab eggs. If you don’t stuff yourself with enough of them, you’ve got nothing to keep you going. And this would be bad news for you, since you’ve burned through not only your fat reserves while in flight, but also a lot of your muscle and organ tissue.
Two or three decades ago, you and your brethren – not just Red Knots but equally crab-egg-dependent Semipalmated Sandpipers, Ruddy Turnstones, and Sanderlings – arrived on the Delaware Bay in unbelievable numbers to partake of this delicacy. You flocked across the Bay shore of two states, filling airspace and obscuring sand to the amazement of birders on such beaches as Slaughter, Fowler, and Prime Hook in Delaware, and Higbee, Reeds, and Norbury’s Landing on the Cape May peninsula of New Jersey.
Cape May Bird Observatory Director Pete Dunne remembers first discovering this spectacle in 1977. “The sound of the birds was a squeaky and chattering din,” he later wrote. “The rattle of the crab shells in the surf recalled crockery in a well-stirred dishpan.”
This area is considered one of the four most important shorebird stop-overs in the entire world. “I think of it as the mid-Atlantic Serengeti,” says Eric Stiles, New Jersey Audubon’s Vice President for Conservation and Stewardship. The other three most crucial migratory shorebird stop-overs are Alaska’s Copper River Delta, the Wadden Sea in northwestern continental Europe, and the Yellow Sea, between eastern China and the Korean peninsula.
For a long time, no one thought the spectacle in the Delaware Bay would end. Dr. Larry Niles, chief biologist with the Conserve Wildlife Foundation of New Jersey, says that, in the 1980s, estimated counts of the rufa Red Knot in Tierra del Fuego numbered about 90,000 individuals.
Suddenly, in the mid- to late-90s, the numbers of Red Knots and other shorebirds appearing on the Bay for their mid-spring horseshoe crab egg gorge-fest fell dramatically. By 1997, Red Knot numbers had shrunk by more than 50% to only 41,855. The real low point came in 2003, when scientists counted a mere 16,255 Red Knots. The number has been fairly stable since then, fluctuating little from the dismal 2004 figure of just 13,315. Meanwhile, the Semipalmated Sandpiper numbers in the Bay have plummeted by 80 percent. But New Jersey Audubon’s Eric Stiles sees the Red Knot as the “flagship species,” the one that is “really emblematic for a whole suite of other species.” In other words, the Red Knot is the “canary in the coal mine” for the conservation status of a whole range of shorebirds.
But what happened? While birders were ooo-ing and aah-ing over the annual spring shorebird entertainment, fishermen once again had their eye on the crabs. Their take had been huge in the late 19th and early 20th centuries, when astronomical numbers of crabs were caught for the fertilizer industry, but shorebirds, severely persecuted by market and plume hunters, were few at the time. These shorebirds, including the Red Knot, rebounded within several decades once they were spared the shotgun and horseshoe crab egg abundance spiked, to the point that the birds became the attraction that Pete Dunne had hailed 30 years ago. During this period of recovery, fishermen had been catching a certain number of horseshoe crabs – especially “egg-laden” females – as bait for minnow and eel. But, by the early 90s, they had learned of another lucrative use for crabs. There was a newly growing conch industry, and crabs were perfect bait for conch. So fishermen began carting away truckloads of the helmet-like animals as they came ashore to spawn; the catch increased from an estimated 100,000 crabs in the early 90s to two million later in the decade.
Fewer horseshoe crabs meant fewer eggs for the Red Knots and other birds, and they did not react well to this state of affairs. By now, the problem was obvious. A temporary moratorium on the harvest of horseshoe crabs declared by New Jersey Governor Christine Todd Whitman, and initially tentative harvest restrictions instituted by the Atlantic States Marine Fisheries Commission (ASMFC) – affecting not only New Jersey and Delaware, but other Atlantic coastal states like Maryland and Virginia – only saw the numbers of Red Knots and other birds continue to decline. The hard fact is that horseshoe crabs take eight to 12 years to reach sexual maturity. Mature and maturing crabs kept being permanently eliminated from circulation.
As a result, on the New Jersey side of Delaware Bay alone, the density of horseshoe crab egg distribution on the beaches remains poor. In 1992, density was 50,000 eggs per square meter. Eight years later, density had fallen to a minimal 4,181 eggs. Two years ago, density was even lower, at 2,006 eggs per square meter.
In 2004, leading scientists believed that, based on data, the rufa subspecies of the Red Knot would go extinct within six years. And this prediction didn’t factor in the potential for a catastrophic oil spill in the Delaware Bay, which is a top U.S. oil transport waterway. Dr. Niles warns that a major spill at the peak of migration could simply wipe out the Red Knot. The birds have enough natural threats now, at a time when their population is “essentially skimming bottom,” as Dr. Niles puts it, without the additional problem of deadly oil slicks.
In New Jersey, a statutory moratorium on horseshoe crab harvesting will remain in effect until various goals are reached. Delaware has yet to enact similar legislation, and a rule imposing a moratorium was overturned in court, but crab fishermen are limited to the maximum harvest of 100,000 set by the ASMFC. The state has taken further initiative by limiting this harvest to males.
The fact that any harvest at all is permitted in the face of the likely extinction of the Red Knot motivated Bill Stewart, the Conservation Chair of the Delmarva Ornithological Society (DOS), to take action. He declares, “If it wasn’t for Delaware, I don’t think that the Red Knot would exist.”
In 2007, he decided to organize a DOS Bird-A-Thon to raise funds for the purchase of Bay shoreline in Delaware then in private hands. Partnering with the Conservation Fund, the DOS agreed to provide $15,000 the first year and, thereafter, donate what turned out to be increasingly more impressive totals, so that the Fund could buy shoreline and turn it over to Prime Hook National Wildlife Refuge for “eternal management.” There, no crab harvesting would take place. So far, the DOS Bird-A-Thon has helped the Conservation Fund purchase 16 acres of shoreline. The Fund is now working on buying 64 more acres (two miles), and a special DOS account has $28,000 in reserve for this purpose, while Stewart expects to raise another $35,000 this year toward that end. (Additional monies support the Ashland Hawk Watch in northern Delaware.)
Last year (2008), the Bird-A-Thon attracted 433 participants of all skill levels who collected pledges based on the number of bird species they saw or heard in Delaware in a 24-hour-period during any one of several days in May. Stewart notes that this fundraiser has enjoyed considerable support from people all over the U.S. who send in checks earmarked for the Bird-A-Thon. This year, the dates for the DOS Bird-A-Thon are May 2-10. People can learn how to participate or simply donate by going to http://www.dosbirds.org/bird-a-thon.
Ultimately, Dr. Niles, Eric Stiles, and other conservationists believe that only a complete moratorium all along the Atlantic coast on horseshoe crab harvesting will allow the rufa subspecies of the Red Rnot to recover. Maryland and Virginia permit harvests off the coast in accordance with ASMFC quotas: Virginia allows 70,000 crabs, which is less than its quota, while Maryland has chosen to harvest its quota of 173,000, but at a rate of two male crabs for every one female. The significant harvests in Maryland and Virginia remove crabs that would have eventually ended up in the Delaware Bay to spawn.
Under former President George W. Bush, work under the Endangered Species Act came to a virtual halt. The U.S. Fish and Wildlife Service has restarted efforts on endangered species under President Barack Obama, and the rufa Red Knot was recently elevated in priority for consideration as endangered. Nevertheless, Dr. Niles urges that we can’t wait for the federal bureaucracy to afford protection to the rufa. Today’s annual crab harvest levels of 400,000 are substantially greater than the estimated harvest prior to the Red Knot’s decline. “Once the crab population gets back to its carrying capacity, where it was before it was over-harvested, then we can harvest crabs and we will have enough crabs to make eggs for shorebirds,” Dr. Niles observes. “We need to get back to that as soon as possible. We’re slowing recovery down because we’re still harvesting 400,000 crabs.”
Acknowledgments and Literature Cited:
In researching this article, the author spoke with Kevin Kalasz, Wildlife Biologist, Delaware Division of Fish and Wildlife; Stewart Michels, Fisheries Scientist, Delaware Division of Fish and Wildlife; Dr. Larry Niles, Chief Biologist, Conserve Wildlife Foundation of New Jersey; Bill Stewart, Conservation Chair, Delmarva Ornithological Society; Eric Stiles, New Jersey Audubon Vice President for Conservation and Stewardship; and Dr. Jean Woods, Curator of Birds, Delaware Museum of Natural History.
The author also relied on the following articles: “Effects of Horseshoe Crab Harvest in Delaware Bay on Red Knots: Are Harvest Restrictions Working?”, Bioscience Magazine, February 2009, by Dr. Larry Niles, Kevin Kalasz, and 18 others; “Horseshoe Crab Spawning Activity in Delaware Bay: 1999-2008,” Report to the Atlantic States Marine Fisheries Commission’s Horseshoe Crab Technical Committee, February 9, 2009, by Stewart Michels (Delaware Division of Fish and Wildlife), David Smith (U.S. Geological Survey), and Sherry Bennett (New Jersey Division of Fish, Game and Wildlife); and “How the Knot Became Undone,” New Jersey Audubon, Spring/Summer 2007, by Pete Dunne.
As stated in the posting of this ID challenge, identifying mixed flocks of flying birds is tough, even when the action is frozen. Our eyes tend to migrate to the most colorful individuals in the group, in this case the male ducks. The less colorful individuals (females) tend not to catch our eye. In general, the plumage of most female ducks tends toward some shade of brown and many female dabbling ducks seem nearly identical to one another in appearance. It takes practice for one to feel comfortable sorting them all out, even when they are sitting on the water. I have to admit, during late summer and early fall, when males attain a cryptic female-like alternate plumage (formerly called eclipse), I'm disinclined to expend much effort sifting through the massive brown swarm of dabbling ducks. Males, females, and immatures...they all look alike, especially through the haze and heatwaves that typify the hottest months of the year. Thankfully, between late fall and early spring (when these images were taken) the males molt back into their distinctive basic plumages and at least half the birds are readily identifiable.
There are five species of waterfowl in the original images posted with this ID challenge. They include four species of dabbling ducks: Northern Shoveler, Cinnamon Teal, Blue-winged Teal, and Green-winged Teal. There is also one species of diving duck: Redhead. With the exception of Green-winged Teal, these images include both males and females of the other four species. There is a single female Green-winged Teal in each of the original images. So, let's go duck hunting, without guns of course.
Just above the male shoveler in the lower right corner of the image above is a male Cinnamon Teal. Its solid cinnamon-brown head, neck, and underparts are unlike any other North American waterfowl. Just below the male Cinnamon Teal is a paler brown female of that species (partially obscured by the male shoveler). If you look closely these male and female Cinnamon Teal, their head shapes and the length and profile of their bills are nearly identical. Also, note that the slope of the forehead feeds right into the slope of the bill with very little angle change.
Just above the male Cinnamon Teal there is a male Blue-winged Teal. The bright white crescent right behind the bill is diagnostic for males of this species. Take notice of the forehead and bill profile of the Blue-winged Teal. First off, the bill is shorter and thinner than that of the Cinnamon Teal. Additionally, the forehead is steeper and, unlike the Cinnamon Teal, there is a fairly distinct slope change between the forehead and the bill.
On the far left margin of this photo, opposite the male Blue-winged Teal, is a very small duck (the left most bird in this image). It is a female Green-winged Teal. Like the other females, it is mostly brown, but note that it does not show a large powder blue wing patch like the other three species. Its speculum, the dark area at the trailing edge of secondary feathers (the flight feathers closest to the body), is bordered above and below by white. Among common North American ducks, only Green-winged Teal and Mallard show this light-dark-light pattern on the speculum. A Mallard (not pictured here) would be much closer in size to the shovelers and would not have an all-dark bill.
In the top left hand quadrant of this image there is a female Northern Shoveler with two smaller females immediately below it. Experienced western birders had a decided advantage in determining the identities of these two birds. They likely presented the most challenging aspect of this image for many of you. The bird on the left is a female Blue-winged Teal and the bird on the right is a female Cinnamon Teal. We've blown-up this section of the photo (see below) to offer a better, though slightly blurry, look at these two birds.
When faced with trying to separate female Blue-winged and Cinnamon Teal, it is important to focus your attention on the head pattern, the bill shape, and the forehead profile. The female Cinnamon Teal (lower right) has an extremely plain face then tends to become slightly paler towards the bill. Further, there is no evidence of any dark markings on the face and this bird does not show a dark line through the eye. The overall color of the head of a female Cinnamon Teal is buffy and "warm." Conversely, the female Blue-winged Teal (lower left) shows some pattern to the face. As seen on this bird, the feathers right behind the bill and on the chin are very pale and near white. This look should be expected on female Blue-winged Teal. It is not shown in this image, but the cheeks of female Blue-winged tend to look a bit grayer on close inspection, giving them a "colder" overall look. Female Blue-wingeds also have a dark line behind the eye and a less obvious dark line in front of the eye. The dark post-ocular stripe is evident on this bird even though the image is a bit blurry, but the dark in front of the eye can't be seen here.
Finally, let's compare the head and bill profiles of these birds. The Cinnamon Teal has a fairly flat slope to its crown, the angle of which does not change much as it meets the upper ridge of the bill. Their bill is a bit longer and, if seen well, slightly spatulate (broadened and spoon-shaped) at the tip. On the female Blue-winged Teal, the forehead is not as steep as it appears on the male in the top image, but there is a noticeable slope change where the feathered forehead meet the base of the bill. The bills of Blue-winged Teal are also shorter, more tapered, and thinner at the tip.
There is just one species of diving duck in the original pair of images. The image above has been cropped from the bottom picture in the original post. There are single male and female Redheads in this image. We'll start with the easier male, which is uppermost bird on the right side of the picture. Its distinctive cinnamon-brown head, black neck and breast, and mostly white underparts set it apart from the other ducks in this picture. What can be seen of the upper wing surface shows no obvious pattern or speculum markings.
In North America, the only species that bears a significant resemblance to a male Redhead is the male Canvasback. However, male Canvasbacks are whiter below and they do not show the contrasting gray flanks below the base of the wing. Additionally, the bill of a Canvasback is all dark with no apparent pattern. Their bill is also longer and more evenly sloped along the upper ridge. Redheads have a more concave ("dished") upper ridge to their bill and the male's bill is bluish gray over the basal two-thirds, with a sub-terminal white band and a black tip marking the outer third. This bill pattern can be seen, but not easily, on this male Redhead.
The bird in the bottom left corner of this image is a female Redhead. It looks a bit odd because there is a female shoveler (mostly obscured) directly behind it. In flight, female Redheads are tough to separate from many female dabbling ducks and female Canvasbacks. We can only see a portion of the upper surface of the far wing of this bird, but there is little if any evidence of pattern. With the exception of Northern Pintail, all the female dabbling ducks of North America show a fairly patterned speculum and even pintails have a pale trailing edge to the speculum. Female Redheads have a warmer more reddish brown plumage than other North American diving ducks, particularly on the head and upper breast. On this bird, note the amount of brown along the flanks below the base of the wing and how that blends with the brown on the breast and neck. If this were a female Canvasback, it would show a darker, more crisply marked breast and neck with little if any brown farther down the flanks and under the wing. This results in a fairly sharp contrast between the dark breast and pale flanks. Female Canvasbacks also appear paler and mostly gray above unlike the darker warm brown upperparts shown by a female Redhead. Like the male Redhead, this female shows a concave bill profile. Female Redheads also show a diffuse pale buffy area around the base of the bill and they also have a subtle buffy eyering. Both of these features can be seen in this image. Female Canvasbacks also show a light ring around the eye, but it is whiter and wider making it more obvious. Female Lesser and Greater Scaup bear some similarities to female Redheads, but they have much darker heads and more constricted white feathering limited to the area right around the base of their bill. Additionally, neither female scaup shows a pale eyering. In flight scaup have broad white wing lines (limited to the secondaries in Lessers, extending onto the primaries in Greaters).
Hopefully, these hints will be of use the next time you are faced with a mixed flock of ducks, either in flight or on the water. When sorting out female dabblers, it is best to pay attention to the overall size, speculum pattern, face pattern, and the bill and head profile. The same can be said for most diving ducks, although the pattern in the wing tends not to be restricted to the speculum (trailing edge of the secondaries). We invite your comments. Let us know if you find this sort of exercise helpful and better yet, how it might be improved. Once again, thanks to Steve Mlodinow for providing the original image, which was taken near LaPaz, Baja California Sur, Mexico in March 2009.
Identifying birds in flight presents a challenge to most birders. The first problem with flying birds is that they are moving, often very quickly. Additionally, we often see birds flying at a distance, thus size is tough to assess, especially with lone birds or homogenous flocks that offer no size context. While most of us avoid trying to identify small passerines in flight, other species, such as raptors, are most often seen flying, thus they are sometimes easier to identify in flight than when perched. A good example of this is the Northern Harrier, which is a slam-dunk ID when seen flying, but might convince you that you are seeing all manner of hawks, falcons, and owls when perched. A friend of a friend coined the term "The Great Fooler" to describe a sitting harrier. In my circle of birding friends, we've come to call Northern Harriers "foolers," which can be quite mystifying to someone birding with us for the first time. "What page is that on?"
Ducks fall into the middle of this spectrum. Their field marks tend to be bold and often readily visible even at a distance. However, ducks are fast fliers and they compound the challenge of identification by mixing in flocks that often include several species. So, for the purposes of this exercise, we have provided a stop action image of a mixed flock of flying ducks. We'll get you started by pointing out that there are five species in these two images, four that are represented by both male and female birds and one species represented only by females. We invite you try to find them all, name them, and post your results to our comments section. I want to thank Steve Mlodinow for providing the excellent original photo that was cropped to create the images below. Good luck.
If a Pacific seabird faced near-extinction due to a flawed U.S. naval decision, you approached this man and he raised the necessary fuss to stop it. If you needed platforms to help New England raptors successfully nest as their numbers mysteriously plummeted, this man arranged for a grant. If the fauna of a fragile, remote atoll in the Indian Ocean were threatened due to military designs of a NATO nation, this man was at the forefront of the cacophony against it. If the “world’s greatest ornithological spectacle,” situated on a lake in East Africa, required preservation, this man ensured its protection.
If a struggling conservation organization sought to enlighten Americans about the natural world, it hired this man to write and lecture on its behalf. If the average person lacked a portable book that “boiled down” a bird’s field marks to their essentials so that it could be identified without shooting it and examining it in the hand, this man wrote and illustrated such a book. If the world didn’t have enough birdwatchers, this man’s book created the birdwatchers and, thus, an army of conservationists whose numbers grew over decades.
There was a time when one man was the go-to person for any environmental crisis or for more mundane educational efforts. That man was Roger Tory Peterson. When in 1908 he was born in the furniture-manufacturing western New York municipality of Jamestown to working-class, immigrant parents, the fledgling Audubon movement was struggling against the millinery trade, which, for the sake of decorating women’s hats, sponsored the mass killing of birds big and small. Widespread “egging” by collectors disrupted nesting colonies. Even after millinery and market hunting of most migratory birds in North America had been banned, young boys still felled songbirds with a slingshot, simply because they could. But in 1920, when Roger was nearly 12, he discovered birds, through the wild-eyed, beckoning flight of a waking northern flicker. Rather than try to kill it, he was smitten, and from then until the day he died on July 28, 1996 at nearly 88, he pursued, explained, and lobbied for birds with his artist’s feel, photographer’s eye, and scientific mind. (Later in adolescence, he mastered butterflies and moths, as well as wildflowers, but birds would remain his utmost passion.)
An embodiment of the American Dream, Roger Tory Peterson rose to the top of his field without earning a single college credit. He sent himself to art school in New York City following his 1925 high school graduation, while immersing himself in avifauna alongside his companions in the Bronx County Bird Club. Upon seeing some of Roger’s patternistic bird drawings, a friend pleaded with him to turn these into a field guide. Finally, 75 years ago, on April 27, 1934, his A Field Guide to the Birds emerged via Houghton Mifflin, dealing a decisive blow to bird-in-the-hand birding. Then a teacher of natural history at the exclusive Rivers School outside Boston, Roger’s fame and acclaim steadily grew; John Baker grabbed the twenty-something youth for the post of education director at what was then called the National Association of Audubon Societies. Roger had mentors, from near and far, of his own – museum scientist Ludlow Griscom, bird portraitist Louis Agassiz Fuertes, author/artist Ernest Thompson Seton, seminal nature photographer Herbert K. Job – but he laid the foundation for modern birding and conservationist thinking, inspiring generations to follow him into the field and learn about and protect what they found. Among his progeny are Pulitzer Prize-winning biologist E. O. Wilson, eco-tourism entrepreneur Victor Emanuel, and field guide author David Sibley. Among his colleagues were the late Yale luminary Charles Remington and brainy British ornithologist James Fisher.
Roger led the way as art director of the National Wildlife Federation; co-founder of the World Wildlife Fund; battler against DDT; and advocate for the Laysan albatross on Midway, the wildlife of Aldabra, the flamingoes of Lake Nakuru, Kenya, and many more birds and animals across the globe. He edited the Peterson Field Guide series as it exploded into dozens of titles. He wrote and painted until his last day. If he were alive on the occasion of his field guide’s 75th anniversary, he would say the same thing he declared in the Foreword to his Burroughs award-winning 1948 volume, Birds Over America: “One cannot give a large share of his life to … [birdwatching] without soberly reflecting on the mechanics of the well-integrated world of nature. One inevitably becomes a fervent conservationist.” And, as one of his earliest benefactors, Boston educator Clarence Allen, once remarked: “Yes, indeed, the birds are glad that Roger came along.”
Every autumn northwest Portland, Oregon hosts a wondrous avian delight that begins in late August and runs into early October, peaking in mid-September. Each evening thousands of southbound Vaux’s Swifts assemble to roost in the old chimney at Chapman Elementary School. While there are other similar sites found from Washington to Northern California, the Chapman Chimney appears to host more swifts than any other roost. Nightly counts of 15,000-20,000 birds are routine during peak migration.
The swifts, which first appear as tiny black specks on the horizon in the late afternoon, accumulate in ever increasing numbers as the light fades. Appearing out of nowhere, they start out circling in loose formation over the general area. As darkness approaches, this holding pattern gradually tightens up around the school and small numbers begin to swoop towards the chimney, dipping towards the opening over and over, though not quite ready to enter. Eventually, the first bird stalls and flutters downwards into the chimney, which triggers the massive swarm to start funneling in. Once the lead bird goes in the rest resemble a vortex of pepper flakes swirling like a tornado, dropping in so quickly that they are impossible to count. Evening after evening one can stand below the chimney and watch these little birds pack themselves one atop the other until no more seem to fit. On many nights as the darkness deepens stragglers who can’t quite fit give up and fly off to the west towards Forest Park. Where these latecomers spend their night is unknown.
Since 1994 The Audubon Society of Portland has been educating the city’s populace about these swifts through their "Swift Watch" program. Every night during September Audubon volunteers answer attendee’s questions, and teach those who come to view this spectacle about this swift’s natural history. Almost every evening a Cooper's Hawk or a Peregrine Falcon enlivens the show by catching a swift or two, so the onlookers also learn about raptors.
Before local forests were intensively logged, migrating Vaux’s Swifts roosted communally in hollow old-growth trees. As these large trees and snags have been lost, the breeding population has declined. With fewer old trees for breeding and roosting, large chimneys like Chapman’s have provided alternative roost sites, offering a stable location that can be taught to each year’s new generation. Several thousand adults have been counted using the chimney during spring migration, though the numbers are far higher during fall when the adults are ushering their young of the year on their first southbound migration.
About 15,000-20,000 can stuff themselves into the chimney during mid-September. The BBC (British Broadcasting Company) filmed these swifts in the 1990’s as part of a documentary. Cameras placed inside the chimney during this filming showed that these birds cling to one another, sometimes up to four deep and they only occupy the top half of the chimney.
Though these events offer a great opportunity to raise community awareness about local birdlife, the crowds now coming to view the swifts during September have grown to the point where they are wearing on the patience of local residents. In 2008 it was estimated that as many as 3000 people came one particular evening. Persistent problems include driveways and streets being blocked by illegally parked cars and litter from picnics. Swift-watchers are encouraged to be respectful of the neighborhood’s residents. It is best to park as far away as you are willing and walk a few extra blocks to the site. Don't expect to find a parking spot along NW Pettygrove (street along the south side of school) after 5 PM. Please stay off of private property, leave the dogs at home, pack out your own garbage, and don’t bring cardboard for your kids to slide on, or if you do please take it home with you. I can personally attest to the amount of garbage left in the area that is found each morning.
While the evening roost activities garner most of the publicity, there is also a show in the morning. The morning departure, however, is much less dramatic and unpredictable as it is more weather and temperature dependent. Usually the swifts leave very early in the morning, but if the weather is unfavorable they return to the chimney. One very windy cold morning I observed small numbers leaving around 11 am. When the swifts do decide to exit the chimney they do so like water bubbling from a fountain. The birds just barely clear the lip of the chimney, then drop to gain speed, before soaring back into the sky on their sojourn south.
All photos taken by Shawneen Finnegan.
A documentary film called "On the Wing" has been produced Portland-based Real Earl Productions. A video trailer for this film and information about upcoming showings can be found at: swiftsmovie.com.
I am going to speak my mind, because I have nothing to lose – S.I. Hayakawa
Frigatebirds have, as far as I can tell, a unique method of bathing. Before we delve into their personal habits, a brief introduction would be appropriate. Frigatebirds consist of five species of tropical/subtropical seabirds in the genus Fregata that are close relatives of pelicans and boobies. All five species are imbued with an aura of speed and power. Indeed, these attributes inspired their English name as well as their Latin name (Fregata). These birds reminded Linnaeus and his crowd of the dreaded era-of-sail warship, the frigate. Like their naval namesake, Frigatebirds are not petite. The wingspan of the aptly named Magnificent Frigatebird, North America’s predominant species, is more than seven feet (88 inches on average). Despite their size, frigatebirds manage to embody aerodynamic elegance: Those long, narrow, angular wings are attached to a slim bullet-shaped body and deeply forked tail. Befitting this gracile build is a lengthy and relatively thin bill. The business end of that beak, however, looks (and is) lethal, rather like a grappling hook. Indeed, it is used in this manner to snatch fish from the water.
Frigatebirds, for all of their magnificence, have a problem. They are rather large birds with narrow wings and itsy-bitsy feet. Thus they cannot leap into the air like a pelican or run along the water/ground like a swan. A frigatebird on the water or the beach is a frigatebird that will never fly again, thus bathing is a challenge. Landing in the water and shimmying about, spreading droplets hither and yon amongst your plumage like a joyful gull is not an option. Well, it is an option, but for a frigatebird, it is the final option, the last bath. When they do land, it is on trees, cliff edges, or since the advent of sailing, masts.
To solve this challenge, frigatebirds use their strength, speed, and maneuverability. Watching frigatebirds bathing is one of the World’s most unappreciated wonders, comparable with breaching whales and leaping manta-rays. I have had the pleasure of enjoying this spectacle a number of times, often in solitude and amid peaceful surroundings, giving the experience even more luster. Typically, a small group of frigates will approach in leisurely fashion, soaring in lazy circles over some lagoon or large freshwater pond (which, amazingly, includes sewage ponds) near saltwater. They come in as if they have nothing particular in mind. “Don’t mind us, we’re just enjoying some especially nice updrafts in the neighborhood.” My guess is that this initial period is one of inspection, during which the frigates are assessing the safety of their chosen bathtub. Then, one or two will suddenly fold their wings and tail and angle sharply downwards towards the water, the change in direction and action is so abrupt as to startle. The stoop earthwards is not dissimilar to that of a diving Peregrine, and likewise the frigate accelerates with an amazing burst of speed. A few feet above the water, this downward bullet abruptly flares its wings, translating much of the downward speed into horizontal velocity, paralleling the water’s surface, with the bird now flashing along a foot or so above the agua infirma. Before too much of this momentum is stolen by drag, the frigate bounces itself once or twice across the water’s surface, and after splashing satisfactorily, labors to become airborne once again. This is done with great effort and a certain air of desperation. As one frigatebird is taking back to the air, another is typically impacting the water.
Once safely airborne, the now semi-waterlogged bather shakes itself grandly. Frigatebirds shed excess water much like a Labrador retriever after a good swim. It all starts with a slight sideways movement of the head, the side-to-side wave gaining amplitude as it travels tailward, resulting in a substantial shimmy of the body followed by a vigorous wag of the tail. The process is often repeated several times. The difference between a Lab and a frigatebird drying itself is that the frigatebird rarely sprays nearby humans with water of dubious origin, and of course, the frigatebirds are shaking and rattling in mid-air, suspended like a marionette during the process. It is nearly impossible to impart the wonderment of watching this simple maneuver with mere words.
Drying Off: The Shimmy and Tail Waggle
Indeed, I was once so inspired that I wantonly shed my clothes and waded enthusiastically into the reservoir, blissfully ignorant of my legs sinking nearly knee-deep into oozing muck. After a bit of splashing around in the cool smelly waters, I struggled back to shore, trying to maintain my momentum and avoid becoming immobilized by mud – much like a frigate trying to gain altitude after its dip. Finally, upon reaching terra firma, I attempted to dry off with a good shake but only managed to hurt my back and achieve an unpleasant sense of vertigo while panicking the nearby stilts and avocets. Just kidding. Or …
The impact of witnessing these huge birds maneuver so skillfully while traveling at great speeds is beyond my skill as an author. However, some of the birds’ beautiful lines, and the humor of the dunk-and-wag, are not beyond the capabilities of my camera. For these, see the five images above of an adult female Magnificent Frigatebird shaking herself dry. All photos were taken on a glorious afternoon in March 2009 at “El Tanque,” a reservoir that is part of the wastewater system of La Paz, Baja California Sur, Mexico.
All photos taken by Steven Mlodinow using a Nikon D300 with a 400mm lens and a 1.4 teleconverter.
The Ring-necked Duck gets its name from the narrow collar of chestnut-brown feathers at the base of the neck of basic-plumaged adult males. This collar does not connect across the hindneck (Hohman and Eberhardt 1998). Many have suggested that Ring-necked Duck should have been named "Ring-billed Duck" for the prominent sub-terminal white band near the tip of its bill. It is rare indeed to catch sight of the ring on this bird’s neck and many birders have never seen this obscure marking. In order to spot the chestnut collar on a male Ring-necked Duck, one must be fairly close to the bird on a bright sunny day and, the bird needs to have it head raised and neck extended in an “alert” position.
Across much of North America, Ring-necked Ducks are only present during the winter months when lighting conditions are sub-optimal and hunting pressures make waterfowl less approachable. Ring-neckeds undergo a pre-basic molt during late fall and early winter, at which time the adult males acquire their chestnut collar. Hence, the collar is at its brightest during the winter months when lighting conditions and distance make it tough to see. In recent years it has been revealed that most duck species, including Ring-neckeds, undergo a pre-alternate--formerly called pre-basic--molt during the breeding season. This molt leaves the males with a muted (“eclipse”) plumage during the late summer and early fall (Pyle 2005). They subsequently molt again during the fall and early winter when they acquire their basic plumage, which, opposite of most species, is their brightest set of feathers (Pyle 2005).
When viewing conditions are ideal, the chestnut “ring” on the neck of an adult male Ring-necked Duck can be surprisingly conspicuous, as it is in the photos included in this essay. However, most observations leave us wondering, “who named this duck?” The species discussed in this three-part series are but a few of many birds named for cryptic field marks best seen on specimens lying in a museum tray. Feel free to share those mis-named species that baffle you by sending us a comment. We’ll endeavor to offer future photo essays like these in an effort to satisfy your curiosity.
Hohman, William L. and Robert T. Eberhardt. 1998. Ring-necked Duck (Aythya collaris), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/329.
Pyle, Peter, 2005. Molts and Plumages of Ducks (Anatinae). Waterbirds 28(2) pp. 208-219.
Violet-green Swallows are a common sight throughout much of western North America from Alaska south through Mexico, particularly around human habitation. In the minds of many familiar with this bird, spring does not commence until the first “Vee-Gees” arrive and begin prospecting their residential neighborhoods for nest sites.
I have often wondered why the “Violet” is capitalized and comes first in the name of this swallow. It really ought to be named the Green violet-rumped Swallow. When this lovely swallow is perched, the purple and blue hues on the lower rump and upper tail coverts are usually difficult and often impossible to see. Their long folded wings typically obscure the rump and upper tail unless you are very close and looking at the bird from the rear. However, in good light the brilliant emerald green back is hard to miss.
As is the case with all swallows, most encounters with Violet-greens involve flying birds. Their flight is characterized by constant changes in direction, acceleration, deceleration, and banking to and fro. Pack a lunch (and maybe a tent and a sleeping bag) if you set out to capture good flight photos of these birds. Sometimes, getting a clear visual impression of color--including the bright green back--is a challenge even in ideal lighting conditions.
Like the crests of a Double-crested Cormorant, the violet on a Violet-green Swallow is a bit of a phantom field mark. I suspect that many new birders have misidentified their initial Violet-greens because they could not find the alleged coloration that the name promises. In the next day or so, we'll visit one of the ultimate cryptic field marks, the ring on the neck of a Ring-necked Duck.
All photos taken by David Irons using a Canon EOS XSI 450D camera and an EF 100-400mm f/4.5-5.6 lens.
New birders and even some of us grizzled veterans are often left to scratch our heads over how certain birds got their names. Many species have handles that emphasize plumage characteristics that we rarely seen in the field. Unlike the museum curators who doled out these misnomers, we don't often see birds stuffed with cotton and lying flat on their backs. Some classic examples of misnamed birds include Red-bellied Woodpecker, Ring-necked Duck, and one of my favorites, the Red-cockaded Woodpecker. I have no idea what a "cockade" is and I'm not sure I want to ask.
It was crisp and sunny here in Eugene, Oregon today, a mega-rarity of late. So rather than spending most of the day staring into a computer screen, I headed out with my camera to fill some of the blank spots in my library of bird photos. I happened upon three species which have names that often puzzle beginning birders. One of these is the Double-crested Cormorant.
Double-crested Cormorants spend most of their lives showing no crest whatsoever, let alone two of them. However, during late winter/early spring they undergo a partial head molt and acquire a set of specialized feathers that form bushy tufts or crests along each side of the crown (Hatch et al. 1999). In profile, these tufts generally go unnoticed, but if you see an adult Double-crested head-on this time of year, their crests can be quite conspicuous. Though both sexes acquire these specialized crown feathers, males typically have more than females. This appearance is short-lived. Most Double-crested Cormorants will shed their extra crown feathers by June (Hatch et al. 1999).
David Irons took all of these photos on 4 April 2009 at Delta Ponds in Eugene, Oregon using a Canon EOS XSI 450D camera and a EF 100-400mm f/4.5-5.6 lens.
Hatch, Jeremy J. and D. V. Weseloh. 1999. Double-crested Cormorant (Phalacrocorax auritus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/441
Over the next couple days we will offer similar photo essays that will discuss how Ring-necked Duck and Violet-green Swallow got their names.
The Horned Lark is among the most wide-spread species in the Northern Hemisphere. It inhabits short grass prairies, deserts, coastal dunes, and agricultural lands throughout the Holarctic Region and is familiar to those who enjoy open country birding in North America. Like many wide-ranging species, it exhibits extensive geographic variation. There are 21 recognized subspecies in North America (Beason 1995). Horned Larks--called Shore Larks in Europe and Asia--are highly variable in terms of the amount of yellow on the breast, throat, and face. They also show substantial variation in back color, which often approximates the local soil color (Phillips 1964).
It is well known that populations of birds dependent on native short-grass ecosystems are in decline across much of North America. Over the last century, human encroachment and conversion to agriculture have dramatically reduced these habitats. Among the birds most impacted by these losses is the “Streaked” Horned Lark (A. a. strigata). Historically, the breeding range of this subspecies extended from southern British Columbia to Northern California and it was a common to abundant nester throughout western Oregon’s Willamette Valley (Altman 2003).
More recently its range has contracted and today Streaked Horned Larks no longer breed in B.C., Washington’s Puget Trough (from Tacoma north), or the Rogue Valley in southwestern Oregon (Pearson and Altman 2005). The remaining population likely numbers fewer than 1400 birds (Altman pers. comm.). Current breeding activity is mostly confined to the southern Willamette Valley and a few sandy islands along the lower Columbia River. Additional nestings have been documented along the Washington’s outer coast and in the Puget lowlands (Pearson and Altman 2005).
For more than a decade researchers have been closely monitoring this fragile population and working to develop management strategies that will maintain and increase suitable habitat on both public and private lands. Hopefully these efforts will turn the tide. The summer songs and the wonderful hues of this subspecies, among the most colorful of all Horned Larks, would surely be missed by this author.
Altman, Bob. 2003. Horned Lark. Pp. 425-428 in Birds of Oregon: A General Reference. D.B. Marshall, M.G. Hunter, and A.L. Contreras, Eds. Oregon State University Press, Corvallis, OR.
Beason, Robert C. 1995. Horned Lark (Eremophila alpestris), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/195.
Pearson, S.F., and B. Altman. 2005. Range-wide Streaked Horned Lark (Eremophila alpestris strigata) Assessment and Preliminary Conservation Strategy. Washington Department of Fish and Wildlife, Olympia, WA. 25pp.
Phillips, A. 1964. Horned Lark. Pages 93-95 in The birds of Arizona. (Phillips, A., J. Marshall, and G. Monson, Eds.) Univ. of Arizona Press, Tucson.
All photos taken by David Irons.