The bays give up their dead?

27 03 2015

Over much of this winter, I heard from Seanetters telling me they were finding what seemed like fewer dead birds on their beaches. This was mainly from the “hotspot” beaches that typically produce a few birds per walk throughout the winter, when bird mortality is generally highest. Many of these Seanetters went many weeks without finding any birds. Now, as spring advances, our northern cohort of Seanetters are seeing the opposite in many places–sometimes over a dozen birds dead on a stretch of beach. We are also hearing from nature centers and other groups who are receiving reports from the public about what seems like a spike in mortality. So is it?

Before I begin, I offer the caveat that we have not actually analyzed these numbers since they are only now coming in, but I can give some impressions and some hypotheses. First let’s look at what’s been turning up. On some beaches, it seems that a particular species dominates among the carcasses. Ray Bosse, walking along Buzzard’s Bay in Massachusets, found eleven Canada geese on his beach on March 22. Ray’s beach does not typically turn up many birds. Compare these snapshots from our database for Ray’s beach during the winter of 2014 vs. the winter of 2015:

RBosse_winter2015
RBosse_winter2014
2014 was a fairly typical year for Ray–a few birds here and there. 2015 looks a bit different. Ray found no birds from November though the end of February, and then an uptick began, culminating in that big day on the 22nd. Compare Ray’s numbers with those of Warren Mumford, walking in Chatham, MA, a part of the Cape facing out toward Nantucket. Warren’s beach is a fairly reliable producer of dead birds, though not in huge numbers all at once. Then, on March 25th, he too saw a sudden influx, finding 17 dead birds on his beach.

MA_27_winter2015
These kinds of spikes draw our eyes, but are they reflecting current, ongoing mortalities, or something else? To figure that out, we need to look at just what kinds of birds were found on each beach, and in what condition they were in. When we do this, we find some differences between beaches. On Ray’s big day in Buzzard’s Bay (a fine title for a morbid children’s book about bird carcasses), he found mostly one species–Canada geese (CAGO). Warren, however, found a grab bag of different species, basically representing the usual species that turn up on his beach: eiders, White-winged scoters, and gulls. When we see so many different species, it does not rule out a disease process, or other common cause of death, but it makes it far less likely. Few causes would impact everything from American Black Ducks to Herring Gulls to Common Eiders. The other point to consider is the condition of the carcasses. Warren’s birds, in addition to being all sorts of species, are in varied states of decomposition and degradation. Some are very weathered, and almost mummified. Others are intact, and look fairly fresh. This tells us that these birds did not die all at the same time.

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A weathered Common Eider carcass. Likely many months dead.

A much more recently dead juvenile gull.

A much more recently dead juvenile gull.

We appear to be seeing accumulated mortality over time, but revealed to us all at once.

In Ray’s case, the geese are all at just about the same level of degradation, suggesting they died within a much narrower timeframe. Multiple specimens of one species, and all dying around the same time raises our eyebrows a bit higher. For this reason, we are planning to collect a few of these geese and perform necropsies on them. The condition of the carcasses will preclude any advanced diagnostics, but we can hopefully look for signs of trauma, and also assess the nutritional state of the birds. It is very possible that the cause of death in these birds was starvation. The harsh winter, one in which many of our sheltered bays (and not so sheltered ones) actually froze over entirely, and massive snowfalls this year, severely reduced the available grass forage for the geese. It’s our current, working hypothesis. Even if the birds died over the course of a few weeks or even a month, the cold and the ice would have preserved them fairly well. They may even have been on the beach the entire time, just concealed by ice and snow and only now becoming visible. This effect might be expected to be even more pronounced in the bays where dead birds were entirely prevented from washing up by the extensive ice sheets from late January through just a week or so ago. On ocean facing beaches, where open water persisted all winter, are these spikes due to birds that were dead on the beach but hidden by snow? Or are these birds drifting in from other previously ice-locked areas?

What even the larger bays looked like this winter. How many dead birds could be locked in that ice?

What even the larger bays looked like this winter. How many dead birds could be locked in that ice?


If the ice-imprisoned carcass hypothesis is correct, then these high numbers of dead birds on many beaches may represent weeks or months worth of mortality all released at once for the finding as the ice and snow rapidly melt. I look forward to seeing what we find in the CAGO from Ray’s beach to see if we seem to be on the right track in our line of thinking. Watch this space for more news.

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More trash talk

2 03 2015
The waste-to-energy plant (incinerator) in Haverhill, MA. I was apparently up in arms about as soon as it opened in 1989. I was nine.

The waste-to-energy plant (incinerator) in Haverhill, MA. I was apparently up in arms about as soon as it opened in 1989. I was nine.

I am always on the lookout for topics to write about here, and when I get a request from a reader for a specific post, I am both happy to oblige and relieved not to have to cast about for a theme. Seanetter Warren Mumford is a Cape Cod resident but was unable to attend the film screening of Trashed and subsequent panel discussion last week, and he asked me to provide a bit more of a synopsis on what occurred. If you’d like to view the film itself, you can stream it, or find it on iTunes. In general, it covers the end result of our global overconsumption of goods, and our tendency toward blindness as to where those goods end up. Landfills, incinerators, recycling plants all feature in the film, as do the places where our trash ends up inadvertently, including, I hardly need tell you, dear readers, the oceans. I was on the panel after the film primarily to speak to the impacts of trash (especially plastics) on marine wildlife. Jessica Donohue is a Research Assistant at SEA Education Association, and brought her expertise on sampling plastics directly from the oceans, and Dave Quinn, Regional Waste Reduction Coordinator for Barnstable County (Cape Cod), spoke to issues of recycling, composting, reusing, and attempting to reduce our overall waste stream wherever possible. The questions from the audience ranged widely from topics of contaminant induced infertility, to cancer clusters, to styrofoam recycling (very challenging, as it turns out), to composting and plastic bag bans.

Highly recommended.

Highly recommended.

I am currently reading the book Toms River by Dan Fagin, about the fate of a small town in New Jersey ravaged by the blithe dumping of chemical wastes from a dye manufacturing plant over multiple decades, so I have been, for the past week, more consumed than usual by matters of waste and waste disposal. Some of the discussion after the film screening centered around what we might do to combat this issue of our mountainous waste problem, and it seems to me fairly consistently the problem that we do not pay the appropriate price for what we use. The statistics in Toms River on the volume of waste water generated per gallon of dye produced is appalling, and as I read, I considered what a poor job we do reflecting those true costs in the sticker prices on consumer goods. The environmental costs of cheap plastic bottles, bags, food containers, and so on, are not captured in the amount we pay, nor in the what the companies must pay to produce and distribute those goods. Dave Quinn brought up the idea of extending the responsibility of these manufacturers to encompass the entire lifespan of these products (or at least more of it since plastics stay with us for thousands of years). If the producers had to consider, and pay for, the ultimate disposal of their products or their products’ packaging, might things not turn out differently? Certainly we would expect the cost of that non-recyclable, non-reusable juice container to go up, and perhaps that would drive down demand for the most egregiously packaged items.

We discussed what consumers might do as well, and in the film, a small urban shop is featured where shoppers buy all items directly out of bulk bins and take them home in their own reusable containers. This shop was a lovely idyll, but I couldn’t help but bring up the issues of environmental justice and uneven access to high quality food, let alone to high quality food responsibly distributed. I tried not to be flip as I described my teaching work in the small, but rather depressed city of Lawrence, Massachusetts, where the underclasses may have access to no food at all save what they can get at the corner convenience store. This was by no means meant to discourage the opening of more environmentally minded retail shops, but simply to raise the issue that we have a very long way to go before they will be routine in places outside the liberal bastions of the posher cities or their suburbs. For my student population, it’s hard for me to get them to simply throw paper in the recycling bin rather than the trash can right beside it. This flabbergasts me, but it’s a good lesson in how little many of my students think about issues that keep me up at night. Trying to break down that barrier is part of why I teach.





Tale of two beaches

24 02 2015

Over the weekend, I had the great pleasure of serving on a panel discussing waste disposal and the impacts of human trash on the environment and human and wildlife health. Many thanks to Annie Hooper and Wellfleet Bay Wildlife Sanctuary for inviting me! While we were down on the Cape for our whirlwind, sub-24 hour visit, we stopped by First Encounter Beach in Eastham, MA. This is a bay-facing beach, rather than an ocean-facing one, so it is more sheltered, with less wave activity, and thus, more prone to at least partial freeze-ups. We were surprised to find, however, that the bay was entirely locked in by piled slabs of ice as far out to the horizon as we could see. It was not clear where the ice-covered beach ended and the ice-covered bay began.

Here's me at the presumptive edge of the bay.

Here’s me at the presumptive edge of the bay.

My sons were thrilled, as they are on a mountaineering kick in their reading, and this was the closest they will be getting to a glacial crevasse field any time soon.
It was good to get to a beach at all, however ice-covered, as the beach I normally walk in Salisbury, MA has been unreachable for the past month. The mile long road in to the parking lot finally succumbed to the drifting snow this month, and last time I tried to go, I had to give up, and drive my poor Prius in reverse for three quarters of a mile back to the state park entrance when blowing snowpiles made the last reaches impassable. I am hopeful for a walk in March, but we will play it by ear. For the Cape Cod Bay beaches, it’s hard to imagine how any dead bird would ever arrive on the beach, with what looks like miles of ice between the sand and the open water. I have to imagine we will see a downtick in beached birds when we look at the data from those beaches for these latter weeks of winter.
Meanwhile, down south, I have a couple photos to share of Seanetter Lori Porwoll. Lori ordered a SEANET shirt from me a year and a half ago, but her check was quite literally lost in the mail. I only recently unearthed it in an unopened packet of mail I found in a closet, and I finally sent her the shirt. As you can see from the pics, it’s warm enough on Lori’s South Carolina beach to wear the shirt (albeit with a layer underneath).

Our walking billboard, Lori.

Our walking billboard, Lori.

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I know it shouldn’t constantly amaze me–the geographic differences in weather–but it always does. In conversation with an acquaintance of mine from Alabama, she asked why hikers and backpackers in New England complain of missing the trail this time of the year. “Why not just go out? A good jacket and some boots are all you really need, right?” I can scarcely convey to her what nine feet of overall snow looks like, nor what it feels like to walk out into -8 degree air this morning to bring water to the chickens. Even my cross-country ski outings have been curtailed this week by severe wind chills. But, as everyone keeps pointing out, “Spring is coming next month!” I can’t argue with calendar spring being close at hand, but right now, the concept of mud season (spring in New England) seems like something I imagined once and have since mostly forgotten. I will be glad to get back out to beach MA_23 at some point. Come to think of it, couldn’t I do a SEANET survey on skis?





Island views, New England style

17 12 2014

Usually, I manage to juggle my SEANET responsibilities amid my teaching ones. These past couple of weeks, as I descended into finals and student hysteria, I had to entirely toggle off you all and this blog. Apologies for that, but I submitted final grades today, and now turn my attention to you all once again. Today, I have a request for help with identifications on some mystery skulls and weathered wings–it seems our reputation precedes us on that score.

The photos come from an island off the Massachusetts coast, and as I paged through them all, there was a good bit of evidence of muskrat activity–trails, little piles of vegetation, and scat everywhere. Muskrats are native to New England, but when they manage to get out to distant islands, and their predators don’t follow, artificially high numbers can result.

Appledore Island in Maine has historically had a high muskrat population as well, and the animals have become so acclimated to humans that they scamper around in plain sight and approach people unnervingly closely. Last summer, however, there was a conspicuous lack of these rodentine islanders. It seems likely that the Snowy Owls that overwintered on the Isles of Shoals fed heavily on the muskrats, to the extent that I did not see a single one during my week on the island. Their homes and trails looked fairly deserted, and muskrat bones and leathery, weathered skin lay strewn about on all the trails.

There were owls up and down the New England coast this past winter, so it may be that the muskrat populations are reduced on other islands too. But on all these islands, unless every last muskrat was eaten, their populations will likely rebound now that the predation pressure is back down to low levels.

Now, for your perusal, the dead bird photos.  I have my strong suspicions regarding their identities, but I want to get some unbiased opinions from you all first.

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Mystery skull 1.

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Mystery Skull 2.

Mystery wings.

Mystery wings.





Carnage on the coast!

18 11 2014

The title here may be somewhat hyperbolic, but the situation on Gil Grant’s North Carolina beach on November 10 was striking. Gil found 7 dead birds, all of which had been thoroughly dismembered and stripped of flesh. For the most part, all that remained were wings and the occasional flayed skull. Six of the birds were laughing gulls, and one was a ring-billed gull.

ggrant6834-16287Whenever several specimens of a single species or closely related species turn up dead at the same time, we always have to consider a disease as a possible cause. But what else could it potentially be? Gil pointed out one likely suspect himself, writing this note on his report: “all 7 gulls today within 1/2 mile of fishing pier, gill nets, and shrimp boats.”

Nice clean skull, possibly thanks to ghost crabs.

Nice clean skull, possibly thanks to ghost crabs.

This is a situation we encounter a few times a year: a suspected case of bycatch, where birds are entangled and killed in fishing gear and then tossed aside. The diagnosis is not easy to make, however, even in fresh carcasses. When a bird is documented coming up dead in a net or other gear, the case is fairly clear. But we often get only a waterlogged carcass washing up on a beach, and it’s much harder to attribute those deaths to bycatch. The situation on Gil’s beach is further complicated by the heavy scavenging of these carcasses.

ggrant6826-16283This scenario is common–larger scavengers like other gulls pick the carcasses apart, and then, on southern beaches, it appears that ghost crabs do a thorough job of cleaning almost all the remaining flesh off the bones with remarkable speed. You can see a crab burrow near a carcass in one of these photos. We don’t see quite this much cleaning off of bones up here in the north, which, to me, is further support of my ghost crab hypothesis, since we don’t have them up here.

Because of the scavenging, there is no way to determine a definitive cause of death in these birds. But we have at least documented the presence of these several carcasses. I have been chatting with researchers interested in tracking bycatch and marine debris, and they are also interested in these more circumstantial cases, so we may soon be contributing photos from cases like Gil’s to that effort as well. You never know to what use your SEANET reports may be put in the name of conservation science!





State of Wellfleet Harbor Conference on November 8th

4 11 2014

Let us continue the Wellfleet theme just a bit longer, shall we? SEANET ally Jenette Kerr sent along word of a great way to spend this Saturday should you find yourself on Cape Cod. Pertinent points to consider: the conference is free and open to the public AND includes a complimentary continental breakfast!

The 12th annual State of Wellfleet Harbor Conference will be held Saturday, November 8 from
8:30 AM–2 PM at the Wellfleet Elementary School. The conference is free and open to the public.

Diamondback terrapin feels that you should attend this conference. (USDA photo by Jenny Mastanuono)

Diamondback terrapin feels that you should attend this conference. (USDA photo by Jenny Mastanuono)

This year’s event features research and other activities related to the planned restoration of tidal flow to the Herring River as well as surveys aimed at learning more about animals that make a living in and near Wellfleet Harbor—oysters, river herring, horseshoe crabs, diamondback terrapins, and ocean sunfish. Among this year’s presenters will be Nauset High School students who’ve teamed up with fifth graders from Wellfleet and Truro to compare oyster growth and mortality in various locations of the Herring River and Mayo Creek.
“I think this year’s conference offers great examples of how our community of scientists, citizens, and organizations are using scientific inquiry at all scales, from satellites to test tubes, to meet our local natural resource challenges,” notes conference founder Abigail Franklin Archer. “I’m also looking forward to hearing from the youngest researchers we’ve ever had present!”
The conference also will feature a field trip on Sunday from 9:30–11:30 AM, a tour of upper Herring River culverts and road crossings led by some of the scientists and conservationists involved in the river’s planned restoration. Details about the conference and field trip can be found at http://www.massaudubon.org/wellfleet-harbor-conference.

Contemplating the Wellfleet area ecosystem from a hammock. Also a good way to spend a Saturday. (Photo by S. Courchesne)

Contemplating the Wellfleet area ecosystem from a hammock. Also a good way to spend a Saturday. (Photo by S. Courchesne)

Sponsors of this year’s State of Wellfleet Harbor Conference include Cape Cod Five Cents Savings Bank, Mid Cape Home Centers, the town of Wellfleet, the Wellfleet Conservation Trust, Friends of the Herring River and Mass Audubon. Food donations are being made by Mac’s Seafood, the Wellfleet Box Lunch, Dunkin Donuts, the South Wellfleet General Store, and PB Boulangerie.

For more information, contact conference coordinator Jenette Kerr at jkerr@massaudubon.org or
508-349-2615.





Arctic seabirds sound their warning; who’s listening?

9 10 2014

This past weekend, New Hampshire Public Radio, my preferred news venue, wrapped up their fall fund drive. I listen even during the drive, possibly out of a self-flagellating penance for not actually donating. There’s something satisying about the guilt. During the fund drive, the announcers were pushing their drawing for a free trip to Costa Rica. “Unbelievable! The biodiversity is higher than anyplace else on Earth!” You’ll get no argument from me on the merits of a Costa Rican getaway, nor on the diversity of species to be found there. But for certain species groups, the highest biodiversity comes not down near the tropics, but near the poles.

I’ve just been reading a report on Arctic seabirds from the Conservation of Arctic Flora and Fauna (CAFF) group. In it, the authors point out that the cold (though ever warming) waters of the northern oceans have historically been a nutrient bonanza on which these birds can rear their young. Now though, the convergence of the mutliple evils we’ve managed to work on our oceans appear to affecting many of these species quite profoundly.

Seabird populations are challenging to study and count. Aside from the breeding season when they come onto land, many of these long distance seafarers lead a nomadic existence and pinning down their numbers is difficult. For some species, we don’t have reliable census data even for the breeding colonies, or, if we do, only for the past few decades or so. These limitations make it hard to pick up on anything but catastrophic population crashes.

What researchers are finding now, is a disconcerting emptiness on many of the colonies. In Iceland, historically a hotbed for seabird breeding, scientists now find empty puffin burrows, eggs or dead chicks rotting in abandoned tern nests, and entire swathes of islands devoid of much bird life at all for several years running. Seabirds tend to long lives, and one or two bad breeding seasons are easily borne. But as more and more years like this pass, where the adults either return to the colony and fail to rear any chicks, or simply don’t attempt to breed at all, the consequences for the future grow more grim. These adults will continue to age and will ultimately die, even if they live 30 or 40 years before that happens. If there have been no young birds coming up to take their places, the results are clear. What still isn’t clear is why these breeding collapses are occurring. The CAFF report points to changes in sea ice, altered prey distributions, and increasing frequency of extreme weather events as possible players. A 100 year storm, after all, can wipe out many adults in a breeding population. When those 100 year storms are coming every four or five years…a population only has so much resilience.
We do know that seabirds will respond to prey availability changes by altering their foraging behavior. This graph depicts the type of prey brought back to the nest by thick-billed murres. Looking at the blue and yellow sections of each bar, we see the shift beginning in the 1990’s from the ice-associated polar cod to capelin as ice breakup came earlier and earlier in the season.

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Whether or not an alternative prey is equally appropriate for rearing nestlings varies with the prey. Such shifts seem to coincide with decreases in chick survival in some species, so it does appear that one fish is not necessarily as good as another.

Pollutants in the foraging waters and in the prey are still an issue, with mercury levels in some seabirds high enough to affect breeding success, and persistent organic compounds like flame retardants and pesticides in eggs at concentrations high enough to make them unfit for human harvest and consumption. Some researchers even point out that warming oceans boost the metabolisms of the fish swimming in them, which could make them able to swim just a bit faster and evade their avian pursuers. For birds already on the thinnest of margins of survival, even an effect so slight would be piling on their troubles.

One thing is perfectly clear in reading through all these reports and into the research itself; while empty-headed commentators on the pretend news try to drum up paranoia and conspiracy theories about the existence of climate change, the scientists are keeping their heads down, scanning for the few eggs or chicks still viable, certain in the knowledge that climate change is wreaking havoc already, and we may be watching these birds disappear.