Dead Bird Quiz answers

26 02 2014

Let’s delve into these, shall we? Bird A, I was very relieved to find, retained a tell-tale characteristic that vastly simplified this i.d.: the feet. The lobed toes with no webs between mark this bird as a grebe. What sort of grebe though? Here on the East Coast, we get three species turning up with some regularity: Pied-billed, Red-necked, and Horned. The feet won’t give us much by which to differentiate those three, so we must turn to other features. Wouter weighed in on this one, noting “It is medium sized with dark axillary feathers. Therefore, I think it’s Red-necked Grebe.” Wouter is basically never wrong, so let’s look at those aspects of this bird that he’s focusing on. The wing chord, making a guesstimate from the ruler in the photo, is somewhere around 16-17cm. The range for Horned Grebes is typically 13-15, and Pied-billeds smaller still at 11-14cm. Our Bird A is somewhat in between the range for Red-necked Grebe (at 18-21cm) and the smaller Horned Grebe. So, how can we make this call? As Wouter points out, the axillaries (or wing pit feathers) are dark in our Bird A. I have been staring at images of Horned Grebe and Red-necked Grebe underwings at the Slater Museum’s wing website, and am frustrated by a fair bit of overlap in their appearance; both species have darker feathers at the wing pit, variably with age and sex, it appears. Add to that that the specimen we have in Bird A looks to potentially have some twisted feathers near the wing pit where the orange tag is attached, so it’s possible that we are looking at the upper surface of those feathers rather than the under. The only other consideration I have here is the foot color. I don’t find a lot of definitive coverage of this, but in my experience, Horned Grebe feet are a paler gray than Red-necked Grebe feet, which makes me lean toward Horned Grebe for this specimen. On the other hand, the primaries look darkish gray, which tends to weigh more on the Red-necked side of the scale, as Horned Grebes tend to have a very white underwing overall. Persuade me, Wouter and any other Red-necked Grebe proponents!

Horned Grebe underwing

Horned Grebe underwing

Red-necked Grebe

Red-necked Grebe

Bird B takes the challenge of the Dead Bird Quiz to yet another dizzying height. This set of wings is in rough shape, but what we can tell is that they’re quite small, there appears to be a pale lengthwise band running along the upper surface, and there is a substantial amount of white on the underwing, particularly through the secondaries. I thought it might be some sort of shorebird, and Wouter did even better, going so far as to say it’s likely either a Semipalmated or a Wilson’s Plover. We don’t get many shorebirds in our SEANET database, so my experience identifying them is limited. These two species are quite similar, however, as detailed in a previous post, and in that case, we had additional parts to judge by–like feet. And heads. So perhaps with this one, we’ll go with “Unknown Plover.”

Forster's Tern in winter plumage (photo: BRian Gratwicke)

Forster’s Tern in winter plumage (photo: BRian Gratwicke)

Bird C will be a cinch for our southern contingent, but I include it because they’re still novel for me. It’s a tern, to be sure, and when confronted with terns, I often sigh and go take a coffee break. But this one is intact, so I actually stand a chance. Bird C has an faint orange tinge to an otherwise black bill, and some black on the head. From one angle, it looks more like a partial black cap with a white forehead, but from the other angle, it looks more like a black eye patch. That feature is what I latched onto, guessing that this is a Forster’s Tern (which is also what Janet Kurz, the finder, identified it as.) Wouter also concurred, citing additionally the white tail edges and light inner primaries to help clinch it. I like this bird for the DBQ especially because the dishevelment of the feathers over the head change the bird’s appearance substantially. This is a challenge we dead bird enthusiasts are accustomed to–plumage that makes the i.d. in a live bird may be substantially altered or even absent in a carcass. Luckily, there were plenty of other aspects of this bird that we could utilize. And I’m glad we all agree on at least one of these!

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Dead Bird Quiz: because I can edition

19 02 2014

It’s winter, and so the birds are dying fast and furious out there. Additionally, since we began our concerted effort at recruiting volunteers in the Carolinas, we now get a steady influx of southern material for the DBQ. Since I am far better versed in the northern species, these additions have been a welcome challenge, and one I pass along to you, dear readers. This DBQ is a bit of grab bag. Tell me what you think!

Bird A, found in December in South Carolina by the Frantom/Huggins team.

Bird A, found in December in South Carolina by the Frantom/Huggins team.

Bird B: Found by the McQuilkens in South Carolina. Wing chord reportedly 11cm.

Bird B: Found by the McQuilkens in South Carolina. Wing chord reportedly 11cm.

Bird B: upper surface of wings

Bird B: upper surface of wings

Bird C: Found by Janet Kurz in North Carolina in January.

Bird C: Found by Janet Kurz in North Carolina in January.

Bird C: ventral side

Bird C: ventral side





The news from Shoals Marine Lab

12 02 2014

Though we are sunk in the depths of winter, it’s not too early to be contemplating plans for the summer. This year, our intrepid gull research/harassment team will be out at the Shoals Marine Lab on Appledore Island seeking out banded gulls and banding the unbanded for Julie Ellis’ ongoing study of gull ecology. Our first customary stint is in May when the birds are arriving and setting up housekeeping, and we are pulling together plans and people for that week. Right now, it looks like we will be able to offer slots to three undergraduates on the team, including two from North Shore Community College in Massachusetts where I teach. I am strongly committed to broadening access to field biology experiences to my college population, who have, by and large, never had an opportunity like this. I will be inviting student applications soon and reviewing the candidates. I know they (and I) will be very grateful for the incredible support and generosity of the donors who pay their way on the island.

A greener time of year on Appledore. (photo: Cornell University)

A greener time of year on Appledore. (photo: Cornell University)

Shoals Marine Lab itself is undergoing some changes, and a major one has just been announced. New Director Jennifer Seavey will be taking over supervision of the lab, leaving behind her current gig at Seahorse Key Marine Lab in Florida. We’re excited to see what the future looks like under this new leadership. There is a strong contingent of faculty, staff and researchers at Shoals who want to make it more inclusive, bringing in students from more schools and more diverse backgrounds than the traditional population of mainly Cornell and University of New Hampshire, which jointly administer the Lab. I look forward to helping in some way with that mission and will keep you posted on the goings-on. And of course, you can be assured of a blog post or two in May featuring windswept rocky crags and eager undergrads scanning the horizon for birds while being pelted with feces.





Snowy owls on every corner

5 02 2014

It’s a snow day here in New Hampshire (again), so what more fitting topic than Snowy Owls as my whole family sits, snow bound, in our house?

This winter has seen remarkable numbers of Snowy Owls making forays south to the Northeast, Great Lakes, and a rare bird even as far south as North Carolina and as far out to sea as Bermuda. It looks like this irruption may be waning, as anecdotal reports from fellow owl-enthusiasts and Seanetters appear to be dwindling, and February is usually when the birds start to disappear from birders’ checklists, at least in a more normal year. Back in December, I went out on my own SEANET survey and spotted two of the owls, one sitting on a jetty at Salisbury Beach Reservation, and one hanging out on someone’s roof, putting one of those plastic Great-Horned Owl decoys to shame.

This event has been so extreme, the birds are even flying into my house.

This event has been so extreme, the birds are even flying into my house.

We’ve gotten a lot of questions about what drove these birds farther south, and the plain and simple answer is, we don’t entirely know. But there is a serious contender in terms of hypotheses. Generally, when birds show up in significant numbers outside their normal range, two categories of causes come to mind: life has become difficult in the homeland and they’re striking out for greener pastures, or, conversely, life has been so good in the homeland that more birds are surviving, and there isn’t room for them all, pushing some of them into new territory in unaccustomed lands. So far, it looks like this latter explanation may be closer to the truth for the Snowy Owls this year. The summer of 2013 was a banner year for small rodents called lemmings up on the Arctic tundra where the owls breed. Given this boom of rodents, the owls were in a heaven of food and may have been able to fledge two or three youngsters from each nest, rather than the one or even zero they’re able to raise in very lean years. Once they leave their parents, those youngsters need to find hunting grounds of their own. With so many owls prowling around, some would have been pushed farther south in search of wide open plains for hunting. Hence, their appearance at airports and coastal marshes here in the U.S.

Complex as the food webs are in the Arctic, they are fairly simple compared to many. The cyclic boom and bust nature of lemming populations looks similar to the classic ecology textbook example of snowshoe hare populations cycling alongside lynx populations. As with that system, it can be challenging to tell whether the collapses in prey species populations is more due to rising pressure from increasing numbers of predators, or because the rising numbers of the prey species are simply eating themselves out of house and home. Whatever the primary driver, it does appear that Snowy Owls were not hurting for lemmings this year, and those of us who’ve had a chance to see the birds this winter are grateful for getting to see them, and because it seems to be reflecting a great success for them this year.

The irruption can’t go on forever, and some of you may not have gotten to see one of these incredible birds this year, but everyone can learn more at the website of Project SNOWstorm, a collaborative research project tracking the birds through both sightings and via satellite transmitters placed on several birds. You can check out the maps showing the travels of individual birds, and follow all their findings as this event draws to a close with the end of winter.