Why Gulls are Fun & Species Profile: Ring-billed Gull

In much of North America–indeed, in much of the world, winter is a time for looking at large numbers of common species. In my part of the world, in central Maryland, thousands upon thousands of Canada Geese augment our year-round populations, and a birder could easily spend hours sifting through them, marveling at the astounding numbers. Another group that explodes here in winter are the gulls. Ring-billed Gulls, especially, flood urban and rural areas alike, loafing on open water, parking lots, and agricultural fields. They are probably the default gull, perhaps even the default water bird, in most of Maryland throughout the year, a status which is solidified in winter.

One might think that such a cosmopolitan species would, therefore be among the most familiar and recognizable birds in the region. To some extent, that’s true. However, there are few more variable species of bird than those of the gull genus Larus, to which the Ring-billed Gull belongs. The Ring-billed is a perfect example of this variation, and a great species to use to show how, despite being among the most frustrating groups to learn about, gulls are also among the most fascinating and enjoyable.

So what does a Ring-billed Gull (RBGU from here out) actually look like? The answer to that question can be as simple or complicated as you want to go. The standard-issue, adult, RBGU in winter has a pale gray back and wings, white body and head, and yellow legs, eyes, and bill. The head is streaked or spotted lightly with dusky gray-brown, the wingtips are jet black with large white spots on them, and the bill has a characteristic black ring about 2/3 of the way out to the tip. It’s a mid-sized bird, but on the mid-to-small end for a gull, especially a Larus gull. It has long-ish legs, long wings, and a well proportioned head that is fairly rounded with a slim, average-length bill. Overall, an adult RBGU looks relatively slender, neat, and clean.

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This is about as close to average as a RBGU gets. This adult bird has neat streaking that is limited to face and crown, a pale gray back, yellow legs, a crisply patterned bill, and a pale yellowish iris

In flight, the effect is very similar. The relatively small head, slender body, and long wings of the RBGU gives it a long-limbed look. The bird lacks the barrel chest of other, larger gulls, and the small head combined with long, slim wings makes it look far lighter-weight. The black wingtips retain the line of white spots, with two larger white spots, known as “mirrors” being revealed on the spread wing.

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The spread wings reveal limited black at the tip of the wings, a line of white spots along the back edge of the wing, and two white mirrors on the two, outermost primary feathers (wingtip feathers)

All on its own, that doesn’t sound too bad. When compared with other gulls, there are similarities, but plenty of distinctions in shape and size and coloration to help distinguish RGBUs from other species. The difficulties start to come in when you consider all the things that can be different from our “average” gull outlined above. Lets start with some of the more consistent changes we can see.

Age is probably the greatest variable in gull identification. Oftentimes, when scanning a large group of gulls, of any species, you will noticed that many of them do not have the smooth, gray-and-white pattern that is expected. Many of them have underparts that are strongly spotted or barred, and the backs may be primarily brown. These birds are most often not, as is sometimes assumed, a different species but different ages of the predominating species. RBGU have three fairly distinct age groups, and many variations of those groups. One group, the adults, have largely been discussed already. The other, most distinct group, is that which includes birds which less than a year old, birds known as first-cycle birds. Shape and size-wise, they are largely identical to adults, but their plumage is worlds away. The white body feathers are barred and smudged with brown, sometimes quite liberally. They have a neat black band across the end of the tail, their dark wingtips lack the white spots and mirrors of adults, and their wings and backs are marked with brown-and-white bars and cross-bars. The closer they get to their first birthday, generally, the more gray they begin to show on the back and wings. The “bare parts” colors are also different than on adults. The eyes are dark blackish-brown, as is the bill. Both gradually turn pale, with the bill often having a pinkish base (as in the photo below) by the time the bird is a few month old. The legs are pink.

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This is a fairly normal looking first-cycle bird. This bird has rather extensive and heavy brown markings across its entire body, but it is starting to show some of the cleaner gray adult feathers on its back. The wing feathers are very neat and sharply patterned, a product of their newness. Dark eyes and pink legs are characteristic of this age as well. The black on the bill is now largely limited to the tip, as the base is mostly pinkish.

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When looking at a first-cycle bird with a spread wing, the black on the wingtips is much more extensive than on an adult, and the primaries lack the white spots and mirrors, as well. The brown barring and mottling is apparent on both the upperside of the wing, and the underside.

 

The other age group is that which encompasses second-cycle birds–birds that are a year old. Their plumage is a mixture of adult and immature feathers. The back is often more completely gray than first-cycle birds, and the underparts and head often whiter. The wing tends to have more gray feathers, and wingtips may have small white spots. However, there are often still isolated dark bars or spots on the flanks and chest, and a few sets of barred, brown-and-white wing feathers usually remain. The bare parts colors are somewhat variable. The bill and legs may begin to turn yellow at this age, but they often have a fleshy, peachy, coloration. The tends to have neat black tip. Eyes are generally still dark, though this is somewhat variable. This is probably the most variable age, and some birds that are late in their first-cycle can look similar.

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This is a more classic-looking second-cycle bird. The back is mostly gray, but there are some retained, brownish wing-coverts. They are relatively pale, the color bleached out of them due to their old age, but they are still evident. The wingtips are plain black, and the eye is still dark. The bird has fairly heavy markings on the chest and head, but it is whiter than the first-cycle birds. The bill is a striking, peachy color and the black bill tip is crisp. The eye remains dark.

 

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This bird is a good example of the ambiguities that sometimes arise in ageing and identifying gulls. The eye is dark, so its not an adult. The bill is rather dark, with little pink, and certainly none of the fleshy peach color of the prior bird. However, the gray on the back is extensive, and its is extensively, but faintly marked below. My guess is that this is an early second-cycle bird. I don’t think those brown wing coverts and trials would be so frayed and bleached if this bird were under a year old.

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Two adult RBGU… Or not? The back bird has a remarkably dark iris if it’s an adult, and the bill doesn’t look as bright yellow as the front bird. So is it a second-cycle? If it is, the gray on the back is remarkably extensive, and there is precious-little barring on the breast. Sometime gulls just don’t do what their supposed to, one of the things that can make them frustrating to learn. I would consider this bird an adult, but a new adult, one that has probably just shed the last of its second-cycle plumage.

 

The next set of variation I’ll look at is head shape. The standard RBGU is often described as pigeon-headed. The crown is rounded, the forehead is moderately steep, and the bills is rather slim but not overly long. A number of birds show that shape, but a reasonable number do not. The photo below is a great example:

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Notice the difference in head shape between the front bird and the back one. The front bird looks like its head is more angular and flatter-crowned than the back bird, and the bill looks longer. It is a head shape that is vaguely reminiscent of the Herring Gull, a much larger Larus species. Recently, I sent this picture to a more experience gull-watcher for his thoughts. He mused that male and female gulls actually differ subtly in shape. The front bird with the flat crown, more sloping forehead, and thus longer-looking bill has a head shape he says is associated, anecdotally, with male RBGU. The RBGU we are familiar with in field guides, and the bird in the back of this photo, is the round-headed, neat-billed female bird.

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Another RBGU with a rather angular head. The more one looks at large numbers of these birds, the more apparent it is that small variations are the norm, and not the exception

Head pattern is another thing that is remarkably variable. The normal head patterning for older (late second-cycle into adult) birds is even, neat streaking across the head, often with slight concentrations of streaks around the eyes and crown. But often times, for no apparent reason, this streaking is nonexistent, almost as if the bird had molted into summer plumage already, but other times, it is so dark and extensive it gives off a hooded pattern. This is just something that needs to borne in mind. There isn’t really an explanation or trick to it, it just is.

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This bird has extensive dark streaking that extends from the crown to the nape of the neck, and down across the birds breast. In addition to its somewhat extreme extent, it is also smudgier than “normal”. The paler throat imparts a hooded appearance. All the same, it is still a RBGU, and adult bird too. See if you can tell why.

 

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This bird is probably less heavily marked than average, but is close to the middle. The streaking is well-defined and occurs in three areas–around the eyes, the nape of the neck, and the crown. This is an often-seen pattern on RBGUs of any age, but especially adults, like this bird.

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If you just saw this photo with no other info, you would probably think it had been taken in June. But winter birds are sometimes this pale on the head. Only the faintest lines of streaks on the forehead, and behind the eye are visible.

 

So the moral of the story? Gulls are variable, weird, and they don’t follow the rules we prescribe for them a lot of the time. However, they are also attractive and ubiquitous members of the birdlife in most regions so it pays to get used to looking at them, and figuring their quirks out. RBGUs are just one example of the variability that gulls show, but this post could have been written about most any species of gull. Gulls are fun, and the more you learn about them, the easier to understand they become.

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Enjoy!

 

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Extinct Needs to Remain Forever

There seems to be one thing that fascinates and terrifies the scientists of the natural world more than almost anything else: extinction. Extinction can be looked at as the pinnacle of evolution. When a species has failed—when there is absolutely nothing left for it to contribute—a slow and steady decline begins. Evolution removes species naturally through extinction, and in doing so, maintains a healthy and viable ecosystem. However, extinction is also a terrible side-effect of the actions of humans. When extinction is caused while a species is still contributing to the health of an ecosystem, it has dire repercussions. This is the tragedy of human-caused extinction. It isn’t just the loss of a species before its time; it is the corruption of a natural process. In either case, extinction has a definite finality. Extinct means forever—or it did until very recently. Now, in today’s world of rapidly evolving technologies for genetic manipulation, we are faced with a full set of new questions that would have seemed outlandish just a few decades ago.

De-extinction is probably the flashiest (and most controversial) development in conservation and wildlife management in history. In an article that ran in the New York Times in February of this year—which has been widely credited with introducing the concept of de-extinction to the general public—Nathaniel Rich characterized de-extinction as an “ambitious, interdisciplinary and slightly loopy project”, which seems something of an understatement when you pause to think about it. De-extinction is exactly what it sounds like—bringing a living creature that has disappeared from our world back into it. For anyone familiar with Jurassic Park, it is a concept straight out of science fiction. It isn’t just ambitious, its borderline audacious.

De-extinction can be “achieved” through a variety of processes. The more traditional method, are somatic cell nuclear transfer, is also the primary method of cloning. In this process, a non-reproductive cell (somatic cell) from the mother has its nucleus replaced with the nucleus of a reproductive cell from the animal to be cloned. The cell is then given an electric shock to promote division and inserted into the mother animal. This technique can only be used, however, on species for which reproductive cells exist—species which have only recently gone extinct, in other words. For species for which that kind of genetic material is not existent, another, more complicated method is used. First the extant species most closely related to the extinct one must be identified. After this, the genomes of the two species must be examined, and the differences between the two inactivated by replacing the segments of code in the extant species with analogous segments from the extinct species. Afterwards, somatic cell nuclear transfer is used, with the main difference being that instead of a reproductive cell from the clone individual being used, the fabricated genetic code is inserted into the somatic cell.

All that scientific jargon aside, the appeal is obvious and deeply tempting. For a real conservationist, there are few things more troubling than seeing a stuffed specimen of a passenger pigeon or sea cow, and the desire to see one of them alive is overwhelming. Furthermore, unlike so many conservation management schemes, de-extinction is actually monetarily possible. Because de-extinction is so ostentatious and futuristic, it attracts donors that would otherwise ignore wildlife issues and conservation concerns for instance, silicon valley types who are heavily invested in the technology being used, and pharmaceutical companies interested in the implications the genetic manipulations might have on future drug-development.

There are also more esoteric—or at least more difficult to prove—arguments in favor of de-extinction. Many of de-extinction’s supporters argue that we have a moral responsibility to bring back species that we condemned to extinction. We had the power to drive them to extinction, and now that we have the power to undo it, we should use it. Rich describes it as “grasping for a silver lining” in a history dotted by conservation failures and relates how a leading conservation ecologist, Stewart Brand, likens de-extinction, and its effect on people, to the re-introduction of some of America’s formerly lost megafauna “it gives people hope when rewilding occurs — when the wolves come back, when the buffalo come back”. When discussing de-extinction with the general public, it is not surprising that this idea of giving people hope and a sense of morality is one of the most commonly heard discussion-points. There is also a very commonly-heard argument about biodiversity. It has long been understood that the more species there are in existence the stronger biodiversity is, and the healthier the planet is. These arguments aren’t really possible to prove—the first is a moral statement, and the second isn’t so much a law of nature as it is a widely accepted theory or hypothesis on the way the world works. But they sound appealing and comforting, and get passed around extensively.

All of this being said, the arguments against de-extinction are many. In April, 2013 National Geographic’s Carl Zimmer wrote a cover story about de-extinction. It was ahead-of-its time, preceding Rich’s article by nearly a year, and so did not gain nearly the press that it probably deserved. In the article, Zimmer begins by describing the first successful attempt to revive an extinct species. A species of mountain goat from Spain was revived when a clone of the endling—the last existing member of a species—was delivered by a closely-related species. The goat returned from the dead, but only for ten minutes. A severe birth defect caused the young goat to suffocate within minutes, and the species was once again lost. This story set the tone for most of Zimmer’s article. He discusses in detail the methods for bringing back species. He is careful to emphasize both their difficulty and their plausibility—something which is common among the opponents of de-extinction. The party-line for Zimmer and like-minded individuals is that while the science is there, it’s not as easy as proponents make it out to be.

This assertion has its values. When you are dealing with controversy with such wide-ranging implications as de-extinction, perspective needs to exist, and the difficulties that would be faced are massive. However, this is not the most convincing argument against de-extinction, and it is at this point that I will turn to an article from May 2012, not about de-extinction, in order to prove a point. Leslie Kaufman ran an article in the New York Times about zoos and the way they manage their collections. She opens her piece by relaying the stories of two attractive and critically endangered primates. One of which is being saved and one which is not. She follows this up by remarking how zookeepers, vets, and collection managers “are increasingly being pressed into making cold calculations about which animals are the most crucial to save”. Zoos, which had, in the past, been imagined as places of entertainment and education, are now adding “modern Noah’s Ark” to their job descriptions. And deciding which animals to let onto this ark is a painful and desperately difficult decision. One of the problems zoos face is balancing this new responsibility as an ark with their more traditional roles.

In doing this, zoos have always faced criticism from factions that think they should be more devoted to conservation and not as interested in providing entertainment. The problem with this is that zoos did not develop to be arks. They developed as entertainment facilities reliant on public donations, admissions sales, and state grants. They certainly cannot gather the first two sources of income without spending a large amount of their time and resources on keeping zoo visitors happy.

Let us, for a moment, investigate the case of the St. Louis Zoo—one of America’s largest and more successful zoological parks. Despite being so large and well respected, this zoo faces the same struggle as any others. These include coming up with new ways of attracting visitors to the facility to meet the bottom lines. At present, the St. Louis Zoo is known in the zoo business for ostentatious and modern exhibits, displaying high-attraction species of conservation concern, including severely endangered black-and-white ruffed lemurs. The investment of money into breeding and maintaining appropriate exhibits for these species is huge, but having these species displayed brings in large numbers of guests. It has the added bonus of contributing to the conservation of these animals. Generally speaking, however, if zoos must choose between conservation and monetary success, they will choose the latter. An example of this comes straight from Kaufman’s article. She notes that while the St. Louis Zoo is highly committed to conservation, they are currently in the process of building $20 million dollar (around 40% of its total operating budget) polar bear exhibit despite the facts that “its last polar bear died in 2009 and the Marine Mammal Protection Act makes it illegal to remove or rescue the bears from the wild”. Additionally, polar bears are known to be quite difficult to breed in captivity, and individuals whose genes are not already overrepresented in the captive population are rare, so acquiring captive bears from other facilities is quite difficult.

Given this, if the St. Louis Zoo were to gain able to create a clone of a mammoth or genetically engineer one using recovered DNA, it is not entirely unreasonable that they might funnel some funds away from the ruffed lemur projects—a, presumably, less monetarily productive program. And if, after this is done, it is proven the mammoths brings in more money than the lemurs, which is all but guaranteed, it is not unreasonable to imagine the lemur breeding program being significantly scaled back, if not entirely phased out. For a population which is not abundantly common in captivity and which is facing near certain extinction in the wild, such a blow could prove fatal for the survival of the entire species.

The scenario outlined above has not happened anywhere yet, thankfully. But it is not hard to imagine how it might. The individuals who run the de-extinction programs are generally not conservation biologists or wildlife vets. They are computer scientists and geneticists who happen to like animals, or some facet of the natural world. As such, their primary interests are bringing extinct animals back and not the consequences these acts may have. No one seems to have thought about, for example, the space that would be needed to exhibit a mammoth in captivity, nor what its specific dietary or medical requirements would be. This, when combined with the issue of the disruption to the current conservation system, becomes, perhaps, the most convincing argument against de-extinction and which jumps to the forefront of my mind when I think of why it makes me uncomfortable.

Yet, this is also the greatest challenge facing the opponents of de-extinction. They are attempting to be accurate and precise and, thus, un-emotional. This is the sciences’ greatest flaw and strength. It is truthful to a fault. Scientists opposed to de-extinction continue to argue against it by saying that it is possible but difficult and flawed. This is perfectly true and relatively unbiased. But the less-constrained and arguably less professional and scientific proponents of de-extinction continue to appeal to the guilt of the public with moral arguments. As long as emotional cries for action are met with quiet and measured responses, the opponents are fighting a losing battle. The opponents need to embrace the more emotional argument I have outlined above—namely the devastating effects de-extinction’s widespread implementation could have on current conservation practices.

De-extinction is a scientific wonder. The very fact that we can bring back entire species from the grave is mind-boggling. And I must admit that it would be both morally gratifying and very reassuring to see a flock of passenger pigeons blotting out the sun again after one hundred years of absence from this world. However, I also recognize that the sentiment expressed by William Beebe, one of the most prominent naturalists of the twentieth century, when he espoused that “when the last individual of a race of living beings breathes no more, another heaven and another earth must pass before such a one can be again” is what has saved countless species from extinction. Threatening to change that now could unbalance the management of endangered species in a spectacular way. If we know that extinction is reversible, there is no moral imperative for us to act to keep species from disappearing. Extinction will become a catalogue of things that the human race has “put on the shelf”; a list of footnotes to be saved for future examination. Ironically, the prevention of future extinctions is reliant on the infallibility of a sober and chilling fact: extinct has always meant forever.

LINKS TO REFERENCED ARTICLES

http://www.nytimes.com/2014/03/02/magazine/the-mammoth-cometh.html?_r=0

http://ngm.nationalgeographic.com/2013/04/125-species-revival/zimmer-text

http://www.nytimes.com/2012/05/28/science/zoos-bitter-choice-to-save-some-species-letting-others-die.html?pagewanted=all&_r=0

 

 

 

The Politics of Taxonomy

The other day, the American Birding Association (ABA) Blog posted an overview to the first part of this year’s American Ornithologists’ Union (AOU) Checklist proposal (which can be found here http://blog.aba.org/2014/12/2015-aou-check-list-proposals-part-1.html). As usual, there were revisions to the family organizations (Parrots, this year), a genus reassignment (American Tree Sparrow), and multiple new splits. The splits included some reasonably predictable ones–Trindade from Herald Petrel, and Rosalia from LeConte’s Thrasher. However, for every split for which a reasonably measured argument can be made, it seems that one split that is more abstract is proposed. This time around, that split goes to the Painted Bunting.

Painted Buntings north of Mexico can be divided into two subspecies. A western subspecies that breeds in brushy areas of the southern Great Plains, and an eastern subspecies that breeds primarily in the coastal southeast. They are likely inseparable in the field, with the primary differences being moult timing and wintering range.

The Painted Bunting is a species whose proposed split is probably less about a biological difference in populations, and more about ornithology and conservations’ politics. The ABA Blog notes that the split proposal suggests treatment of the two populations as separate species as a way to create a more favorable environment for conservation of the eastern subspecies, which is relatively uncommon and declining. I have had long-discussions with other birders around my age, in which we have both questioned the way that the AOU seems to be deciding which populations of birds deserve full-species recognition. I at least, am not willing to hold anyone at fault for attempting to help a population of creatures that is threatened, but I wonder if the best way to do this is to elevate threatened populations to species status. I am of the opinion that the current trend of elevating many many populations of birds to full species status in order to make conservation funds reach them more easily, or because of differences in mitochondrial DNA that do not translate into field identification is diluting the definition of a species.

In the cases of elevating populations for genetic differences, moult-timing differences etc, the picture is much more complicated. But in the case of raising populations for the purpose of conserving them more easily and effectively, I think that there is a solution that will preserve the vitality of the species definition and protect the species–and it does not come from the AOU at all. I think the solution must come from the governments charged with protecting the populations. The governments must have the ability to recognize populations which are locally threatened and maybe not a full species, and offer them the same kind of protection on the basis that they are a locally significant part of the flora and fauna.

I understand that, until and unless this happens, there will, necessarily, have to be other ways of protecting these populations, and that it is, by some, considered valid to use species recognition as a way of doing this. I don’t have any solutions to this “problem”, but I do think it should be noted that this olution has ramifications for the science of taxonomy and genetics. Just some food for thought…