Travels of tagged birds

Kathleen Kelly, who walks Old Orchard Beach in Maine, was rather surprised, on her December 29th survey, to find a Herring Gull tagged in usual SEANET fashion (orange cable ties on wing and legs) that she’d never seen before. It appeared that a bird tagged elsewhere had turned up on Kathleen’s beach. Turns out, her beach abuts the territory of another dedicated Seanetter, Barbara Grunden. Going back into our database, it turns out that Barbara had found and tagged a Herring Gull on November 18th. More than a month later, it turned up a ways south on Kathleen’s beach.

Herring Gull found on ME_54 in mid-November. (photo: B and C Grunden)

The same Herring Gull, though well-weathered now, on ME_81. (photo: K. Kelly)

If we ever doubted the merits of tagging birds, here’s a case that reminds us to continue. Had this bird not been tagged, it would have been counted twice, as separate birds on two separate beaches, inflating the tallies for both. This case also shows us that one cannot rely on a carcass’ position on the beach to identify it. Many of our Seanetters make notes like, “must be the same bird from last month; is in same spot.” While it could be the same bird, this case demonstrates that whether it’s tides, waves, scavengers, or dogs doing the moving, carcasses do travel.

We had another case of following a tagged bird on its travels at least up to the point of its death this month; Nat Goddard, walking for us on Cape Cod, found a whole slew of dead Common Eiders late in October. One of these was a banded male (or parts of it anyway). Nat got this info from the banding lab when he reported the number:

Hatched in 2005 or
earlier, in Lockport, Nova Scotia, Canada (Coordinates: LAT: 43.58333; LON: 65.08333).  Bander c/o Randy Milton, Nova Scotia Dept of Natural Resources, 136 Exhibition Street, Kentville NS B4N 4E5.

What’s left of a banded male Common Eider (photo: N. Goddard)

Banded in Nova Scotia more than seven years ago; found dead on Cape Cod in 2013. Where he went in between, no one knows.

Whether the banders ever got any sightings in between this bird’s banding and his death, we don’t know, though it’s unlikely. Federal bands are small and difficult to read on live birds, and in a sea duck with its legs almost perpetually in the water, the task approaches impossibility. What various travels this bird undertook over the past several years, we’ll never know. But presumably it traversed the Gulf of Maine several times. Remarkable survivors, especially as I contemplate my own SEANET walk today; the temperature right now has yet to break 10 degrees. Of course, as the eiders know, a down coat goes a long way.

Happy New Year, Seanetters!

On the lookout for Razorbills

Bad as this tired old seabird joke may be, it is timely. Christmas-time coincides with the presence of large numbers of alcids off the shores of the east coast, and this year is no exception. Doug McNair counted 4-5,000 Razorbills off Cape Cod on December 20th, and Tony Diamond, seabird scientist at the Atlantic Laboratory for Avian Research at the University of New Brunswick tells us that a Razorbill was found beached in Florida as well. Normally, Florida would be fairly far afield for these northern birds, but after last year’s unprecedented southern irruption, nothing would surprise us.

Razorbills and guillemots on the water. (photo geograph.org)

So we’re putting out a plea to Seanetters and non-Seanetters alike: keep your eyes peeled, go birding on the beach, and report what you see. If you SEANET, great! If not, and you only want to report live birds, please sign up for an ebird account and start reporting! And if you’re not a Seanetter and you find a sick or dead bird, report it to the Wildlife Health Event Reporter. We’re eager to see how this winter compares with last, and we’re counting on you all to help. Let us know what you spot!

Loons in trouble?

This time of year, Common Loons have arrived on the ocean wintering waters, far from the northern lakes where they breed. But the minds of many scientists and conservationists are still on the breeding season. An opinion piece out in the Boston Globe recently speaks to a troubling decline in chick survivorship. The causes of this are unknown as yet, but what is sure is that too many years of poor survival among chicks will eventually lead to a future with fewer adult loons. This is a discouraging thought, after years of intensive protection and management had led to substantial increases in the loon population overall.

The trouble isn’t limited to chicks either. On Squam Lake in New Hampshire, the mid 2000s saw precipitous declines in numbers of breeding adult loons. Since the worst year of the decline, between 2004 and 2005, modest gains in breeding pairs have been made, but overall reproductive success has been depressed. On Squam Lake too, it appears, it’s getting harder to raise chicks to fledgling age.

The Loon Preservation Committee launched an initiative to study the problem on Squam Lake, and they have some answers, many more hypotheses, and ever more questions. What is clear is that even when a species has begun to recover well from an historic population decline, we have to remain vigilant, even as research dollars shift away toward more imminent troubles. The mindset that we “fix” biodiversity threats, brush off our hands and walk away is clearly not a functional one. We’ll be watching the news out of the LPC and from Biodiversity Research Institute, among many others, to see what news they have to bring about loons. Here’s hoping that scenes like this one, which I filmed from my kayak in Maine this summer, continue to be common on our New England lakes for generations to come–both our generations, and theirs.

Dead Bird Quiz answers

Alright, so Bird C was a gimme–big yellow raptor feet, black body, white head and tail: gotta be an adult Bald Eagle, and so it was. Gil, who found the bird, reports to us that the carcass was transferred to US Fish and Wildlife via North Carolina Wildlife Resources Commission.

Birds A and B, being incomplete (mere wings, in fact) presented greater challenges to our intrepid quiz players. Bird A, on first glance appeared tricky. A dark wing covered in sand, it was a bit hard to make out the identity of the species based on the upper wing photo. Fortunately, we had a closeup of the details of the underwing, which was light overall, but with a small brownish line of feathers near the wrist. That appearance is distinctive and marks this bird as an American Black Duck. Fortunately, you needn’t take my word for it, since both John Stanton and Wouter van Gestel rang in and concurred on that one.

Bird B: White arrow points to the long, luxurious tertials that mark it as not a Dovekie, which has short, businesslike ones.

Bird B was a tricky one and not a species we see reported everyday. At first glance, it appears we have a nondescript dark wing with a slightly lighter, though still gray, underwing. Plain dark wings with dark undersides generally bring a short list of possibilities to mind: ducks (surf scoters and black scoters, for instance) and cormorants. But in this case, there was one marking that leads us in a different direction. Looking at that underwing, one can see a whitish color to the ends of the secondary feathers. So, now we have a dark upper wing, dark underwing, but with some white to the secondaries. In our upcoming Field Guide to Beached Birds of the Southeastern U.S., I’ve devised a key to severed wings, and when I use that guide on our Bird B, it takes me to Dovekie, which wouldn’t be a bad guess, except for some outstanding discrepancies. First, based on the ruler in the photo of Bird B’s wing, the wing chord is too long to be a Dovekie, which have very small wings (11-13 cm). Our Bird B looks to be in the 18-20cm range instead. Also, if you look at the underside of Bird B’s wing, you can see the primaries are dark, the secondaries have a white band, and the tertials are rather long, protruding well past the secondaries. This is typical of many duck species, but also of a bird that does not appear in the new Field Guide primarily because it’s not truly a seabird. The American Coot is, I would posit, the most likely identity of this bird. I am bolstered in my opinion by that of Gil Grant, who found it, and also thought it was a coot, and by Wouter, who said the same.

American Coots are not typically on my mind when I’m reviewing SEANET walks. It’s not that we don’t have them up here in New England, but they just aren’t regular finds (though a little farther south, Jerry Golub in New Jersey has found several in his tenure with us). This Bird B was a good reminder of how even unusual birds can be accurately identified: first, look at the specimen and see if it fits with a common species. If yes, you’re probably all set. But if there are characteristics that don’t jive with your list of usual suspects, focus on those details and see where they lead. Sometimes, it might be right down the path to the elusive and secretive coot.

American Coots in action with wings still attached. (Photo: Wing-chi Poon)

Dead Bird Quiz! (You know what to do.)

Bird A: Found by Kathleen Kelly in Maine last month.(photo: K. Kelly)

Bird A: underside of wing (photo: K. Kelly)

Bird B: Found by Gil Grant in North Carolina this month. (photo: G. Grant)

Bird B: underside of wing (photo: G. Grant)

Bird C: just for novelty’s sake. Also found by Gil Grant in North Carolina (photo: G. Grant)

Risky business: how we view wildlife disease

In October, a study came out in the Journal of Wildlife Diseases examining how Americans assess the risks posed to them from diseases that originate or circulate in wildlife populations. Humans are notoriously poor at allocating risk; swimming at a beach where a shark has been sighted recently gives a person pause, while climbing into a car each morning for a drive down the highway raises not an eyebrow, despite the fact that vastly, vastly more people will die on the roads in one year in America alone than were killed by sharks worldwide over the past decade. In this, we magnify the risk of shark attack and minimize the risk of driving.

Based on this trend, and in my general interest in wildlife disease, I was most interested in the findings of this recent study. The researchers sent questionnaires to random recipients all over the country. The respondents were asked about one of three diseases: rabies virus; the mosquito-borne West Nile Virus (WNV); and plague, which is caused by the bacterium Yersinia pestis and circulates in rodent populations out west. Respondents were asked about their impressions of severity of risk (how dire are the consequences of infection?), susceptibility (how likely is it that infection will occur?), and dread (how much worry or anxiety does thinking about the disease induce?). Finally, they were asked to assess all these impressions in terms of human health; the health of pets, livestock and other domestic animals; and the health of wildlife.

Survey distributed to respondents nationwide.

Perhaps cynically, I had assumed that the average American would mainly be concerned with human health and domestic animal health. What the study showed, however, was that respondents were quite concerned about the impacts of disease on wildlife themselves. Overall, respondents tended to feel that the severity of risk was greatest for humans (this makes sense–if one’s child contracts rabies, for instance, the personal consequences are enormous), but both susceptibility and dread were quite high when ranking risk to wildlife. Respondents were particularly concerned about diseases known to arise or spread when human disturbance alters a region’s ecology. Lyme disease, Hantavirus, West Nile Virus and many others are now known to undergo shifts in infection patterns, prevalence and exposure risk based on human alterations to the environment.

Some other general trends revealed in this study may offer additional insights into how best to educate the public. Women tended to perceive greater risks across the board than men, while a college degree and greater age were linked to a decline in overall assessment of risk. Contrary to the study authors’ expectations, respondents with young children assigned less risk to all three diseases, than those without young children, though the underlying reasons for this are unclear and warrant further study.

What this paper does show is that we need not always take the human health angle when communicating with the public about wildlife diseases. It appears that many Americans are at least somewhat concerned with the health and survival of wildlife populations for their own sake. This affinity for wildlife can be enlisted in a push for greater understanding of the interrelatedness of human, domestic animal and wildlife health. This concept of One Health seems to be gaining traction, I am pleased to see. I am also gratified to see that education is a strong predictor of accurate risk assessment. These two points underpin the basic approach we take here at SEANET: in education and preservation of wildlife lie the salvation of the world.

Tagging birds and humane concerns

One of the things I find most rewarding about maintaining this blog is the contact it gives up with people outside the SEANET community. When members of the public see anything unusual in the seabird world, they tend to head straight to the internet and google what they’ve seen. Searching “tagged bird” or “tagged gull,” or “dead bird on beach” for instance, will bring up our blog among the first few results.

Last week, I received an email from a woman in Massachusetts alerting me to an ongoing discussion among birders and bird photographers about the appropriate treatment of rare and unusual birds. How much disturbance is acceptable, for instance, in pursuit of the perfect shot, or ideal view? In the course of this discussion, humane concerns for the birds came up often, and someone brought up banding and tagging birds under that umbrella.

I visited one of the photo fora where the discussions were taking place, and was surprised to find a picture of a SEANET tagged bird, bearing its orange cable ties and aluminum tag. The caption suggested that the bird had died from the tag’s presence, and that it was cruel practice. Of course, we at SEANET tag only dead birds, so cruelty and humane treatment are not relevant to our study, but public perception certainly is, so I elected to take the opportunity to educate the public about some of the ongoing bird tagging studies they may encounter in their travels, particularly here in New England.

A SEANET tagged bird: orange cable ties and an aluminum tag are placed post-mortem. (photo: W. Stanton)

The purpose of marking, banding or tagging any bird is to study it. By recording all sightings of a given bird after it is captured and marked, scientists can get at least a rough picture of where it travels, rests, breeds, and so on. The larger and more conspicuous the marking, the more likely the bird is to be noticed, recorded and reported. The spectrum runs from the metal, federal bands placed on the legs of songbirds caught in mist nets, to large fluorescent wing tags with obvious alphanumeric codes. Even the largest of the metal federal bands are impossible to read with the naked eye on a live bird with any power to get away, and so these are generally only reported when a bird is recaptured and the band can be read in the hand, or by birders with spotting scopes and a lot pf patience, or when the bird is found dead. This means that very little can be gleaned about a bird’s travels when only a federal band is placed.

Field readable bands boost resightings well above plain metal bands. (photo: Jon Worthen)

To help boost sightings, many projects (including our own Julie Ellis’ study on gulls breeding on Appledore Island, Maine) utilize what are known as “field readable bands.” These are usually brightly colored PVC or metal bands with a short, clear alphanumeric code. These bands can be read easily with binoculars, or if a bird (a gull, for instance) approaches closely in order to steal your sandwich. While using the field readable bands does substantially boost resightings, it’s still mainly people with binoculars or at least a nice camera who record and report these bands.

A ring-billed gull tagged for the Mass. DCR study.

A few steps beyond field readable bands are the gaudy, fluorescent wing tags used, for instance, by the Massachusetts’ Department of Conservation and Recreation water quality study. These large tags result in amazing resight rates. Around 70% of birds tagged in this way are seen by a member of the public at least once subsequent to release. This is several times the resighting rate attained in many studies using only field readable leg bands. I wrote to Dan Clark, who is one of the principal investigators on the DCR study, and asked him about the tagging methods, and how they respond to people worried about the impacts the tags have on the birds. He responded,

“We have tagged over 1500 gulls.  These gulls have flown hundreds of miles (ranging from Florida to Newfoundland), strongly suggesting that the tags don’t interfere with flight, and individuals have survived multiple years with the tags.  These tags are not permanent – they eventually come off.  The gulls we’ve recaptured without their tags show a small area of scar tissue where the tag was, but no damage to the wing or ability to fly.  It is important to recognize that any wildlife study that handles and marks individuals always has the potential to influence the behavior or life expectancy of the animal.  Researchers must always weigh the importance of the data being collected against the potential to impact the study animal.  We were careful in our preparation and execution of tagging.  We sprayed each tag with antiseptic before deployment to discourage bacteria.  Of all the tagged birds we released, less than 10 were found dead or injured.  In only 2-3 cases was the wing-tag suspected of contributing to their condition.  We felt our study objectives (gulls and drinking water quality for 2.2 million people in metro Boston) justified the capture and marking of individual gulls.  The data we received has contributed to our knowledge of inland gull ecology and informed our management decisions as we strive to maintain high water quality standards.”

To give you a sense of the anatomy of the wing where the tags are placed, take a look at the diagram below.

The black triangle roughly outlines an area called the patagium. This is a membranous region of skin with an elastic tendon at the leading edge. There are no bones in this area, nor are there any blood vessels. This makes it a very good candidate for placing a wing tag. The DCR tags were affixed by making a small puncture in that patagium and securing a rivet through the hole. The most apt parallel in humans would be an ear piercing. As Dan pointed out, complications from these tags are exceedingly rare.

While Dan is finished with the wing tagging aspect of his study, these are long-lived birds, and you are likely to see them out and about for several years. Hopefully you will spot a few and report them, and please, help us spread the word to concerned members of the public–these are well-supervised, well thought out studies carried out by dedicated and conscientious wildlife scientists. We welcome your thoughts, comments, and questions, via email or via comments here on the blog.

Happy tagged bird sighting!