Dead Bird Quiz answers, at long last

18 06 2013

An inexcusable delay in posting these answers–I blame my travel debacle of late last week. More on that next time. As for the DBQ, I must thank the universe for bringing Wouter to this blog as Bird A is a perfect example of how dead bird i.d. is basically nothing like live bird i.d. Wouter posted this explication on Bird A:

Bird A has a very wide pelvis, a shape that is typical for a goose or duck. The wing is white with black primaries, which fits snow goose or male eider. Because there may be a black secondary and a few black body feathers in the picture, my guess is male Common Eider (Somateria mollissima)

Interestingly/coincidentally, we did have our very first snow goose reported to the database back in April. Wendy Stanton found this bird on Pea Island in North Carolina:

What do you think of that!?

What do you think of that!?

We don’t even have snow goose as an option in our species list! In all honesty, I wouldn’t know a snow goose if it hit me in the head, but after seeing Wendy’s report, it looks like a good fit. Anyway, if you look at this photo, you’ll see the darker primaries that Wouter mentioned. But male eiders have those too, and when in doubt, it’s generally best to go with the common species. As we learned in vet school, when you hear hoofbeats, think horses, not zebras. Of course, being a wildlife vet, this is probably less reliable advice for me…

Bird B is far more intact than Bird A, but still poses some challenges. The feet are useful, and in the photo, it’s clear that all four toes are webbed, marking the bird as a pouchbill (cormorants, pelicans and such.) Though the bill is not fully visible here, we can say it’s no pelican. The wedge-shaped tail says cormorant. But which kind? We don’t have measurements on this bird, and devoted blog reader BiologistOnTheEdge (not her real name) points out that in field guides for normal people (i.e. live bird field guides), cormorants have reported body lengths of over 90cm, and this bird looks smaller than that. It’s a point that got me thinking–what is the deal with those body lengths given in live bird guides? How can you even judge that in a live bird? And is it the measurement from bill to tail tip? Or to toetips? In any case, it’s true that this bird is not 90cm long. But it is a cormorant nonetheless.
The amount of white on the belly tells us this is a juvenile, but of which species? The head is so weather-beaten we can’t really see the throat color, which would have a white patch in a great cormorant and would be brown in a young double-crested. The belly of this bird is quite white looking, so I was initially thinking it was a young great cormorant, whose bellies look like this:

A juvenile Great Cormorant. (photo by Libby Rock)

A juvenile Great Cormorant. (photo by Libby Rock)

Lots of white on the belly, contrasting with a brownish neck. Double-crested cormorant juveniles, on the other hand, tend to have a more brownish overall color to the neck and belly, with little contrast between them, like this:

Juvenile DCCO (photo by S. Courchesne)

Juvenile DCCO (photo by S. Courchesne)

The difference seems quite obvious until you consider that juvenile DCCOs can also look like this:

Juvenile DCCO (photo by Gil Grant)

Juvenile DCCO (photo by Gil Grant)

or even this:

Another one (photo by E. Walker)

Another one (photo by E. Walker)

What Sibley notes as “variation in color of juveniles” is, therefore, quite substantial, and to my mind would include the amount of paleness in our Bird B, especially noting the lack of contrast between breast and belly. And though I don’t take much stock in wing chords guesstimated from photos, this one does seem small enough to be a double-crested.

As usual, I am open to arguing this one back and forth, so if you think I’m missing something, please, dear readers, do call me out. I know you’re not shy about that anyway.





Dead Bird Quiz: there may be no hope edition

10 06 2013

Helen Rasmussen, who walks in Portland Maine, found this bedraggled, waterlogged, mostly skeletal and entirely inside out carcass on her beach this month. She suggested it might be a candidate for the Dead Bird Quiz, and I concur. Not certain we’ll get a species i.d. here, but I do have a great deal of faith in you players of the DBQ. Got any thoughts?

Bird A's wing. One of the only feathered bits still recognizable.

Bird A’s wing. One of the only feathered bits still recognizable.

Bird A's spine, pelvis and leg bones.

Bird A’s spine, pelvis and leg bones.

Bird B was found by Janet Kurz in North Carolina at the end of last month. Janet apologized for forgetting to take measurements of this bird, but asked if we might not figure it out just from the appearance. I think we can! I think she made the right i.d. on this bird, but let’s see if you all agree.

Bird B's underside.

Bird B’s underside.





The (fiscal) year in review

7 06 2013

It’s a rainy, meditative morning here in New Hampshire, and as a snapping turtle lays eggs near my radish patch, I fall to the task of summarizing SEANET’s activities over the past year for our funders. I enjoy this activity, in some ways, as it’s a welcome opportunity to look at our many accomplishments. Despite my having been able to devote only 5-10 hours a week to SEANET this year, I think we’ve done alright for ourselves. Have a look at our summary and see if you agree. Thanks to all of you volunteers and supporters for keeping this program going on a shoestring!

Working from home dictates a creative definition of coworkers. Here's mine today.

Working from home dictates a creative definition of coworkers. Here’s mine today.

This year, we continued our volunteer recruiting activities, focusing on the Northeast and South Carolina. Trainings in Wellfleet and Duxbury, MA as well as Branford, CT have generated 20 new volunteers so far. Nearly fifty people have signed up to attend a training workshop in Charleston, SC on June 13, and an additional workshop is planned for coastal Connecticut this month.

We continue to find new and novel uses for our data, and have entered into an agreement with CapeWind to facilitate the monitoring of seabird mortality before and after the implementation of their Nantucket Sound wind farm project. The SEANET database is now automatically feeding into the Wildlife Health Event Reporter (www.wher.org) at USGS, and the public can view all SEANET reports of beached birds. We have made a major push to review and verify all historic SEANET survey reports, and our data verification is now up to date, reflecting real-time mortality and facilitating use by collaborators. Our large archive of frozen seabird tissue samples from SEANET necropsies have been transported to the American Museum of Natural History in New York so that they may be made available and readily accessible to researchers.

SEANET tracked several mortality events this winter, including heavy die-offs of Razorbills, Common Loons, and unusually high numbers of dead Horned Grebes and Atlantic Puffins. These data will be included in a presentation to the Wildlife Disease Association meeting in July. We also presented a well-attended talk on Common Eider mortalities at the Wellfleet Bay Wildlife Sanctuary on Cape Cod, and for the second year in a row, presented a seminar on citizen science and beached bird surveys to the Tufts Masters of Conservation Medicine students.

Work on the Guide to Beached Birds of the Southeastern United States is accelerating, and all necessary photos and permissions have been obtained from a variety of sources, including SEANET volunteers, amateur and professional photographers and bloggers, and the Museum of Comparative Zoology at Harvard. Most of the book’s content has been passed to the design and layout team, and printing is anticipated this fall.

 

Hurray for SEANET!





Plodding progress on Field Guide to SE Beached Birds

3 06 2013

I’m certain you’ve all been desperate for an update on the Field Guide to Beached Birds of the Southeastern United States. I, for one, have had the southeast on my mind more than usual, between working on the guide and preparing for a training session in South Carolina later this month. Since you are all undoubtedly eager to see how the book is coming along, I thought I would share a glimpse of what I’m working on right now. Most of the individual species pages are ready to go, so I have been drawing up the Group introduction pages, giving an overview of each species group. Here’s the mockup (not yet polished by Beth Mellor, our design and layout pro):

Slide3

I’m really excited to be entering the final stretches of the long process of writing this book. As with childbirth and running marathons, I suspect I will need a long period of forgetting before I take on a project of such magnitude again. My continued thanks to John Stanton for being my stalwart cheerleader in this venture.





More on gillnets: an inadvertent experiment

29 05 2013

Coming close on the heels of last week’s post about estimated worldwide seabird bycatch in gillnets, an experiment that basically did itself. Paul Regular, William Montevecchi and several colleagues have a paper out in Biological Letters examining the effect of the closure of two major Canadian fisheries on murre populations. In 1992, cod and salmon gillnetting was effectively closed down in Atlantic Canada. This resulted in the removal of tens of thousands of gillnets from the foraging waters of seabirds like murres and razorbills, which are heavily impacted by bycatch in these nets. What followed was thus a kind of de facto experiment on the population impact of removing bycatch mortality for these birds. The study authors looked at impacts not only on birds likely to be entangled in gillnets, but also surface feeding seabirds like gulls which are comparatively unlikely to suffer that fate.

Populations of Herring Gulls and Common Murres before and after gillnet moratorium (Regular, et al.)

Populations of Herring Gulls and Common Murres before and after gillnet moratorium (Regular, et al.)

Using both bycatch data and breeding colony census information, the paper tracks the populations of the various species over the decades since the fisheries closures. Data was sufficiently robust to look closely at two species: Common Murres and Herring Gulls. The researchers found a dual and approximately opposite effect on the two species. Murre numbers climbed substantially once pressure from gillnets was removed, but Herring Gull numbers showed a decline. This is likely due to the withdrawal of offal and other fisheries waste when the gill nets were hauled up and stowed away in 1992. Opportunistic feeders, gulls feed heavily on discarded bait and other material tossed overboard by fishermen. As those anthropogenic food sources become less available, gull survival declines. The same phenomenon seems to have followed the closure of many open landfills after the 1970s. The declines in breeding gull populations over the past 30 years seem to reflect a “correction” of sorts–a return to baseline numbers in the absence of man-made buffets. Simultaneously, more specialized feeders like murres have benefited not only from closure of some fisheries, but also from stricter laws governing the discharge of petroleum products by ships off the coasts of the U.S. and Canada.

The closure of the cod and salmon gillnet fisheries in Canada afforded this opportunity to study the effects of bycatch pressure on seabirds, and it appears to be substantial. Fisheries don’t generally remain closed forever though, and if and when the salmon and cod fisheries off the Canadian Maritimes do reopen, the authors of the study point to potential changes in methods to continue to protect murres and other diving birds. One such possibility is cod pots, which operate similar to lobster traps, sitting on the ocean bottom with bait inside. Fish swim in and can’t swim out. This type of gear is highly unlikely to entrap seabirds, though I have known lobstermen who reported finding Common Eiders in their traps from time to time, so never say never.





Request for video clips of Seanetters in action!

24 05 2013
Even the most squeamish among the students sidled up eventually.

The world from a Seanetter’s perspective. Show us how you do it, folks!

My dear Seanetters, we have been invited to run a crowdfunding campaign through the science funding start up Endeavorist! We’re going to set a target of $8,000 to fund necropsies of seabirds involved in mass mortality events. I think we can do it, but to catch the eyes (and the wallets) of potential donors, we need to produce a engaging and compelling 2 minute video. I want to put together a little montage of beach walking footage. Here’s what I need from you:

You can record your video on an iPhone or similar device, so no need for fancy equipment. You can choose to appear on camera talking about SEANET, or you can submit footage (with voiceover or not) from your first person perspective looking out at the world. I would especially like to get footage of your feet as they walk along the beach (so you would literally point the camera at your feet as you walk. About 10 seconds of that is sufficient). Then I can string together a bunch of different people’s feet walking on different kinds of beaches.

If you find a dead bird, I would LOVE some footage of how you process it–tagging it, measuring, any of that stuff. Again, you can have someone else film you, or you can film from your own perspective. Shaky video is ok–I can work with it, and some of that ambiance is desirable.

Anything else you want to film is most welcome–the feel of your beach, why you SEANET, live birds hanging out, anything and everything, Seanetters!

Help a girl out here, and let’s see if we can’t raise 8K!

 

 





Seabird entanglement in gillnets: a global assessment

22 05 2013

Most of the time, when a dead bird is reported on a SEANET beach, we never find out what happened to it. Whether it’s a lack of resources to perform necropsies, or simply that no cause was evident at necropsy and no more extensive diagnostics could be performed, we often end up with unsatisfying partial answers. It’s the nature of the game, I’m afraid. But once in a while, a Seanetter comes upon a pile of waterlogged carcasses along a short stretch of beach. In many of those cases, necropsy is rewarding and the findings are consistent with drowning in fishing gear. We can never say with complete certainty what happened, except in cases where a bird is documented as its hauled up in the net, but we have seen certain signs in drowned birds that are consistent across events and across species.

Hauling in a gill net. Fish are usually caught by their gill covers but may be entangled in other arrangements too.

Hauling in a gill net. Fish are usually caught by their gill covers but may be entangled in other arrangements too.

Most of the time, the species involved in these sorts of events are Red-throated Loons. These birds forage near shore, swimming underwater in pursuit of fish. The most likely culprit in their drownings are near-shore gillnets–a veritable wall of mostly invisible monofilament that the birds don’t notice until its too late. While NOAA here in the U.S. stations marine observers on ocean-going fishing vessels to document bycatch of non-target fish and of marine mammals and seabirds, the near-shore fisheries are woefully under-monitored. We suspect that birds hauled up in such nets are tossed overboard and occasionally turn up in large batches on shore. It’s a difficult phenomenon to track and delineate, as evidenced by an ambitious review article in Biological Conservation. The study sought to identify particular species groups that are most susceptible to gillnet entanglement (think loons and alcids–razorbills, murres, etc) and also areas across the globe where those species are most likely to be severely impacted. Sub-polar and temperate regions (like most of SEANET territory) are high on the latter list. The study also documented some surprising findings, like that gulls, not generally thought particularly vulnerable to gillnets since they tend to feed on near the surface, are, in fact impacted as well.

A slew of Red-throated Loons found on Long Island. Gillnet entanglement was our suspicion here. (Photo by Peg Hart)

A slew of Red-throated Loons found on Long Island. Gillnet entanglement was our suspicion here. (Photo by Peg Hart)

The paper points out what we have been frustrated by for years–the lack of coordinated monitoring and documentation of bycatch in this fishery. By piecing together published and unpublished data from all over the world, these authors estimate a minimum of 400,000 seabirds are killed in gillnets each year, and they suspect the real number is considerably higher. As for what to do about it, the paper does not venture to make recommendations, but has pointed out some promising research into making the nets more visible to the birds, changing the depth at which they are deployed, or, in some cases, switching to another form of gear altogether, though in some cases this last method may only shift the problem to a new species group.

We’re glad this issue is gaining more attention throughout the world, and we will continue to try to do our part in documenting the extent of the problem here on the east coast.








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