Presumed hybrid gull sighting in Florida!

31 03 2009


Presumed LBBG x HERG chick sighted by Mitchell Harris in Florida (photo by the same).

Presumed LBBG x HERG chick sighted by Mitchell Harris in Florida (photo by the same).

Faithful readers of the SEANET blog will be familiar with the tale of the Lesser Black-Backed Gull observed mated to a Herring Gull on Appledore Island in Maine last summer (see Adventures of a Euro Gull and Update on Julie’s LBBG). The presumed hybrid chicks raised by the pair were banded by Dr. Julie Ellis last summer and nothing had been heard from either one of them…until now. 

One of the birds, sporting a green band on its left leg reading F02, turned up amidst the droves of other, non-celebrity gulls at a landfill in Volusia County, Florida. While birding at the site, Mitchell Harris surreptitiously snapped a picture of the bird and sent it along to Julie here at SEANET. The diminutive gull is decidedly smaller than the average Herring Gull juvenile, and looks mostly like a Lesser Black-Backed Gull from the field reports, but that tell-tale band points to this bird’s unusual heritage.

Dr. Ellis obtained feather samples from the chicks when she banded them last summer, and will soon be submitting them for genetic confirmation of the birds’ hybrid status. For now, we are thrilled that Florida birders have managed to turn up not one, but two needles in the proverbial haystack, finding both the Lesser Black-Backed himself and one of his presumed offspring. Since gulls generally wander for a few years before attaining sexual maturity and heading up to breeding colonies, we have no idea where this young bird may elect to travel next. As Dr. Ellis’ field assistant, Bill Clark, pointed out, it will be interesting to see if this bird summers in Florida, travels up to New England for the warmer months, or does something else entirely. Thanks to all the birders out there keeping their eyes peeled for these banded birds, and especially to Mitchell Harris for this particular report. We will keep everyone posted as we hear further updates on this unusual gull family.

Dead Bird Quiz Plus…answer?

27 03 2009
Could the perpetrator have been a Peregrine?

Could the perpetrator have been a Peregrine?

Well, as Jenette pointed out, this one is both intriguing and grisly. The bird pictured in yesterday’s post is indeed a female Common Goldeneye. Usually our volunteers come across relatively intact carcasses with perhaps a couple of smallish holes due to gull scavenging. Alternatively, of course, many of you find nothing but wings and a well cleaned off keel. This bird seems to be something between those extremes, and the carcass appears quite fresh, as if the perpetrator of this deed had been interrupted mid-meal.

Certainly Peregrine falcons are known to skin their kills and will often even leave the skin over the breast pulled up over the prey’s head. They will then tear the breast muscle away from the sternum as they eat. These bird connoisseurs of the raptor world must remain on our suspect list.

I put this question to bird expert Dr. Richard Veit who had this to say after viewing the photos, “I’ve never seen anything quite like this – it looks like the bird has been skinned.  Peregrine sounds like a possibility. Seals in the Antarctic do something like this with penguins, so I would offer the possibility of a gray seal, but that is just a guess.”

Or perhaps the fierce Gray Seal?

Or perhaps the fierce Gray Seal?



Indeed, we have had volunteers reporting seals occasionally taking eiders and scoters off the surface of the ocean, so our Goldeneye may have fallen victim to just such an event and then washed ashore once the satiated seal abandoned the carcass. 

Of course, we cannot know for sure, but that is the nature of CSI: SEANET. All of you volunteers keep us on our toes with your finds and observations from the field, so keep them coming! We even welcome your photos of things other than dead birds, remarkably, so don’t be shy. You too could attain worldwide fame by being featured on the SEANET blog.

Dead Bird Quiz Plus

26 03 2009

Just when you were probably feeling a bit more confident in your bird i.d. skills, SEANET is throwing a new factor into the mix. Not only do we invite guesses as to species, but in this case, we are also curious about your thoughts on the cause of this bird’s demise.

Carcass found last week by Ray Bosse (LC_03a), Buzzard's Bay Massachusetts

Carcass found last week by Ray Bosse (LC_03a), Buzzard's Bay Massachusetts

The ventral, or belly side, view of the bird (lower photo) shows that almost all the skin has been removed and much of the muscle over the sternum has been scraped away. Volunteer Ray Bosse, who found the bird, wondered what might have inflicted such damage. We at SEANET have our own musings and speculative commentary to offer, but we are interested in hearing from you. Have you ever seen a similar sight on your beach? Do you have any ideas as to what might have done this sort of damage? Any master naturalists out there with an answer for us?

Ventral view of carcass found by Ray Bosse.

Ventral view of carcass found by Ray Bosse.

Tune in tomorrow for the thoughts of amateurs and experts alike!

SEANET in North Carolina

24 03 2009
Hammocks Beach State Park: not a bad place for a business meeting.

Hammocks Beach State Park: not a bad place for a business meeting.

On March 12, SEANET’s Dr. Julie Ellis attended the North Carolina Waterbird Managment Committee Meeting at Hammocks State Park, NC. The program included presentations on topics ranging from shorebirds nesting at the Marine Corps’ Camp Lejeune to the impacts of raccoons in barrier island ecology to genetic diversity research in seabirds. Julie’s presentation on SEANET garnered a great deal of interest, and some leads on potential collaborators in the state.

Julie also had the chance to spend some time with Sue Cameron of the North Carolina Wildlife Resources Commission. When Julie wasn’t too busy wolfing down the wild teal served by Sue’s hunter/chef husband, she had some great conversations with Sue who has previously been involved with SEANET’s investigations into Greater Shearwater die-offs up and down the east coast.

While our potential expansion into the Carolinas has been undertaken cautiously to this point, with a mind toward SEANET’s limited funding and personnel, we recognize that the region is a rich ecosystem critical to many seabird species, and we are encouraged by the interest and enthusiasm for our project among our Carolinian brethren. Thanks to all those who are interested in getting involved, and welcome!

Photos wanted!

23 03 2009
Photos of (dead) marine mammals and sea turtles wanted! (Photo by DolphinCare UK)

Photos of (dead) marine mammals and sea turtles wanted! (Photo by DolphinCare UK)

Our sister program, COASST, is working on a field guide to stranded marine mammals and sea turtles. While COASST is focused on the Pacific Northwest and Alaska, many of the species they see out there also turn up on our eastern beaches. Since many of you Seanetters also moonlight with marine mammal and sea turtle stranding programs, we thought you all might be able to contribute photos to this worthy effort.

The list provided below includes the bicoastal species you may encounter out there.

Our friends at COASST will accept hard copies of photos, or digital photos, of course. Feel free to send photos you may already have, and keep the project in mind should you come across any of these unfortunate animals in the future. You can send the photos to us here at SEANET and we will serve as a liaison to COASST for you.

Keep in mind the same guidelines for getting high quality photos you use for dead seabirds; shoot from directly above the carcass and include the whole body in the shot. As always, keep safety in mind, and do not approach an animal if it is still alive, as stranded animals may feel vulnerable and could therefore become dangerous.

Harbor Seal (Phoca vitulina)
Humpback Whale (Megaptera novaeangliae)
Minke Whale (Balaenoptera acutorostrata)
Bryde’s Whale (Balaenoptera edeni)
Sei Whale (Balaenoptera borealis)
Fin Whale (Balaenoptera physalus)
Blue Whale (Balaenoptera musculus)
Sperm Whale (Physeter macrocephalus)
Pygmy Sperm Whale (Kogia breviceps)
Dwarf Sperm Whale (Kogia sima)
Cuvier’s Beaked Whale (Ziphius cavirostris)
Blainville’s Beaked Whale (Mesoplodon densirostris)
(Possibly) Beluga (Delphinapterus leucas)
Rough-toothed Dolphin (Steno bredanensis)
Common Bottlenose Dolphin (Tursiops truncatus)
Pantropical Spotted Dolphin (Stenella attenuata)
Striped Dolphin (Stenella coeruleoalba)
Short-beaked Common Dolphin (Delphinus delphis)
Risso’s Dolphin (Grampus griseus)
False Killer Whale (Pseudorca crassidens)
Killer Whale (Orcinus orca)
Short-finned Pilot Whale (Globicephala macrorhynchus)
Harbor Porpoise (Phocoena phocoena)

Green Sea Turtle (Chelonia mydas)
Loggerhead Turtle (Caretta caretta)
Hawksbill Turtle (Eretmochelys imbricata)
Kemp’s Ridley (Lepidochelys kempi)
Leatherback Turtle (Dermochelys coriacea)

Gannet die-off in Virginia

20 03 2009
Chesapeake Bay. The Gannets were found in Norfolk, VA (at the bottom of the map)

Chesapeake Bay. The Gannets were found in Norfolk, VA (at the bottom of the map)

SEANET received word this week of a number of “large birds” found dead on a beach in Norfolk, Virginia. A concerned resident contacted the USDA who headed out to the beach and found five Northern Gannet carcasses. The finding has generated a flurry of emails between seabird experts up and down the east coast. The USDA took their standard samples and reported that the birds appeared to have been in the water for some time.

As with any die-off event, regardless of scale, all possibilities must be considered until more information is available. Trauma, disease, toxin, and entanglement in fishing gear are just some of the potential causes of such die-offs.

Entanglement is certainly high on the list given the circumstances of this particular die-off, and Gina Shield, Fishery Biologist for NOAA’s National Marine Fisheries Service, reports that their fisheries observers “frequently document fishery interactions between Northern Gannets and commercial fisheries in the Winter/Spring in the Mid-Atlantic.  Interactions occur primarily in herring/mackerel trawl, gillnet and beach seine and often multiple birds are taken on a given trip.  We haven’t documented any NOGA takes in Feb or March in that area but that is likely a function of  lack of coverage.”

Additionally, Doug Forsell, Migratory Bird Biologist with the U.S. Fish and Wildlife Service, tells us “This is a regular occurrence in southern Virginia at this time of year as large numbers of gannets, common and red-throated loons, and red-breasted mergansers are drowned in gillnets as they move up the coast.” Doug also points out that these birds are usually otherwise healthy, and not emaciated, though they may show signs of trauma from the entanglement.

This points out the importance of a full investigation into die-offs, since without a thorough examination of the affected birds, it is impossible to determine a cause of death, or even to rule out any of the potential causes. Ideally, the birds would be submitted for postmortem examinations and testing. The mid-Atlantic is, at this point, outside of SEANET’s reach, and we currently have no volunteer presence there. We appreciate the information from all the parties who have been involved in discussions of this die-off, and it underscores the need for continued communication. SEANET also sees the mid-Atlantic as its major priority for future expansion, once our southeast and NewEngland programs are stable and fully sustainable.

We will keep you informed of any further developments on this story, so stay tuned to the blog.


Dead Bird Quiz answers

18 03 2009

Brian offered the correct answers to yesterday’s Dead Bird Quiz; indeed, Bird A is a Red-throated Loon, and Bird B a Common Loon.  The two species turn up relatively frequently on SEANET beaches during the winter months before heading inland to breed, be it to lakes and large ponds in Canada and the northern U.S. for the Common Loon, or to ponds of the northern coastal tundra for the Red-throated.

When placed side by side, a significant size difference would be immediately evident between the two species; the Red-throated is the smallest member of the loon family, averaging around 3lbs, while the Common Loon typically weighs in around 9lbs. Rare is the instance, however, when a  Seanetter is presented with a specimen of each species lying side by side.

Common Loon found by Jenette Kerr of Cape Cod. Note the heavy, thick bill.

Common Loon found by Jenette Kerr of Cape Cod. Note the heavy, thick bill.

Of course, the well-equipped Seanetter is much like a Boy Scout, and is always prepared with calipers to measure such things as tarsus and culmen length, which will readily distinguish between the species. But let us inhabit, for a moment, the hypothetical land where our intrepid Seanetter has forgotten her calipers and ruler at home. What other cues might she use in determining the i.d. of a loon-looking bird?

The two photos in this post illustrate one of the most striking differences. The bill of the Common Loon is heavy, thick and straight. The bill of the Red-throated loon is thinner and upturned, conveying something of a sneer, at least to this blogger’s mind. You may, of course, judge for yourself when next you encounter one of these birds on your beach.

Red-throated Loon found by Marcie Lindsay of Rhode Island. Note the thin, upturned bill in comparison with that of the Common Loon above.

Red-throated Loon found by Marcie Lindsay of Rhode Island. Note the thin, upturned bill in comparison with that of the Common Loon above.

Dead Bird Quiz

17 03 2009
Bird A: Found by Marcie Lindsay of Rhode Island in February.

Bird A: Found by Marcie Lindsay of Rhode Island in February.

Bird B: Also found by Marcie Lindsay in January.

Bird B: Also found by Marcie Lindsay in January.

This post has inadvertently turned into the Marcie Lindsay show! Marcie is a Seanetter down in Rhode Island and her photos are reliably well done, showing the salient features of the birds she finds. This makes them excellent candidates for the Dead Bird Quiz.

Offer up your thoughts on these two, and tomorrow’s post will be chock full of helpful identification tips, as you have come to expect from the SEANET blog.

SEANET at WAZE Symposium

16 03 2009

header-2 Over the weekend, a veterinary student group here at Tufts held an excellent symposium entitled “Bridging the Gaps to One Health.” The concept of One Health has been promoted a great deal at the vet school and focuses on promoting communication and collaboration between veterinarians, physicians, ecologists and a host of other professionals and members of the public on issues of conservation.

The student group, known as WAZE (Wildlife Aquatics Zoo Exotics), put together a diverse and talented slate of speakers who brought a variety of perspectives to the topic. You can check out the speakers’ biographies and other related links at the Symposium’s website by clicking on the image at left. SEANET merited a much appreciated mention by Dr. Terry Norton, Director of the Georgia Sea Tutle Center, with whom SEANET met on a recent trip down south (see the previous post “SEANET goes to Georgia“). Additionally, Dr. Inga Sidor, a veterinary pathologist at the University of New Hampshire, spoke about a bacterial disease known as Brucellosis in marine mammals. Dr. Sidor has been in discussions with SEANET about contributing her time to SEANET’s necropsy efforts, bringing to the project her extensive experience with and interest in marine organisms and their pathology.

SEANET was very impressed indeed with the WAZE’s students ambitious program, and thoroughly enjoyed the day. We encourage all of you to attend the Symposium next year as it is open to members of the public for a modest fee.

Tern identification

12 03 2009

While terns don’t tend to turn up (sorry, irresistible pun) on SEANET beaches with anything approaching the frequency of gulls, occasionally we do receive reports of these delicate gull cousins. Often, all that is left is a single wing after the scavengers and the elements have done their work. Such cases have been part of the need behind our new Field Guide to Severed Wings. Since most differentiation of tern species is based on features of the bill, head or tail, identifications based on wings alone are quite difficult.

Common Tern. Wing Chord: 25.1cm

breeding Common Tern. Wing Chord: 25.1cm

breeding Roseate Tern. Wing Chord: 22.6cm

breeding Roseate Tern. Wing Chord: 22.6cm

breeding Least Tern. Wing chord: 16.6cm

breeding Least Tern. Wing chord: 16.6cm

A Seanetter presented with the three wings above, for instance, might well be whipsawed by indecision as to species. Based on appearance alone, they all share a pale gray color, dark outermost primaries, and white margins to the primaries and secondaries. That hapless Seanetter need not despair, however. Take a look at the wing chords listed beneath each picture. You’ll note that the Least Tern is far and away the smallest, and is therefore less likely to be confused with the other two. But the Roseate vs. Common differentiation is quite a bit more challenging. Wing chord for Common Terns falls between 25 and 27cm, while Roseate Terns range from 22 to 24cm. There is, therefore, no overlap between the two, but it does require the Seanetter to be fastidious about the wing chord measurement. Remember, wing chord runs from the wrist (carpal joint) to the tip of the longest primary with the wing held in a natural, folded position, and without flattening the wing against the ruler. If you follow those rules, you should get a clear answer between these two terns every time.