Call of the Wild: Loons
Lab results on Squam eggs from the worst years of the decline, 2005 through 2007, showed surprising spikes in several toxic chemicals, including high levels of two “legacy contaminants”: PCBs, which had been banned from manufacturing in 1979, and chlordane, a pesticide banned in 1988. Newer toxins, such as those found in the stain repellant PFOS and the flame retardant PBDE-99, also appeared well above levels known to affect birds.
The questions were baffling. Was some unseen “point source” of these toxins leaking into Squam? In Maine, Dave Evers, head of BRI, worried about the effect on loons of toxic cyanobacteria “blooms.” Beyond toxins, were smallmouth bass outcompeting perch, the loons’ preferred freshwater prey? What was the effect of recent extreme weather patterns: unusually raw springs and unusually wet summers? Why had the declines disproportionately affected the large lakes? In the years since the 2007 low-water mark, the populations on those lakes had recovered only slightly. How significant were the lab results, given all the factors that historically affect loon nesting? Was it possible that chemicals in the air and water, perhaps in combination with a changing climate, were incrementally, invisibly changing the very ecology of freshwater lakes?
Researchers around New England had more leads than money, no results that definitively fingered a single culprit, but LPC’s executive director, Harry Vogel, spoke of a shared, sinking sense that their work could be touching the edges of a much bigger crisis. If loons were failing on Squam, despite a longer history of successful intervention than anywhere else on the planet, then loons all across New England, and perhaps beyond, were in peril.
There was at least one other place to look for answers. Loon biologists, almost to a person, are freshwater biologists; not surprisingly, their research focuses on the birds’ summer breeding grounds. In the last decade, however, pioneering banding and transmitter work has helped researchers determine that New England’s loons are true Yankees, moving between northern lakes in the summer and the frigid ocean between Maine and Rhode Island in the winter. Quietly floating offshore, with dull-gray plumage in place of their distinctive white-and-black, wintering loons are difficult to observe. Biologists know little about their life on the ocean.
Paul Spitzer was one of the few researchers looking there for clues. He had long studied osprey colonies on Long Island Sound and had been stunned by recent precipitous declines in those colonies to levels even below the DDT era. Spitzer had observed an equally dramatic fall-off in populations of wintering loons in Chesapeake Bay and off the coast of North Carolina. Rafts of migrating loons that had once numbered above a thousand birds had dwindled to less than a hundred. He speculated that osprey and loons, both fish-eating birds, might be reacting to the collapse in the population of menhaden, a once-prolific, small, silvery fish related to herrings and alewives, and an important part of the birds’ winter diet. His work in the Mid-Atlantic raised the possibility that a similar loss of forage fish fit somewhere into the New England loon puzzle.
While the picture on the wintering grounds remained murky, two separate events off the New England coast would reveal hard, clear numbers. During a winter storm in 1996, the barge North Cape ran aground off Rhode Island. Some 828,000 gallons of home heating oil leaked in large underwater plumes into Block Island Sound. Following the spill, 400 dead loons were recovered. Seven years later, an oil spill in Buzzard’s Bay killed more than 200 loons as they flocked up for spring migration. Knowing what we know now, it’s probable that most of them, perhaps all, had flown to the ocean from lakes across New England.
In the aftermath of the Buzzard’s Bay spill, several organizations around the Northeast, including LPC, BRI, and Vermont’s Loon Recovery Project, filed a joint request for damages that might support their recovery work. Eight years on, the wheels of compensatory justice have yet to grind out a settlement. At the end of 2010, $6 million was awarded to mitigate fouled shoreline habitat. “Loons are still in the queue,” says Vogel.
Meanwhile, loon groups across the region were feeling the pinch of the recession, their shoestrings pulled about as tight as they could go. In Vermont, Eric Hanson went to halftime, five months a year; no longer able to afford the insurance, he sold the project’s only boat.
Then during the spring and into the summer of 2010, crude oil poured from the destroyed Deepwater Horizon drilling rig off the coast of Louisiana. Similar to the North Cape spill, much of the oil spread out in deep underwater plumes. The spill began just after breeding loons had left for their summer grounds, sending shockwaves through the community of loon researchers, even 2,000 miles away in New England. BRI’s Dave Evers was called in to assess the spill’s injury to birds. Susie Burbidge cleaned oiled birds on the Gulf before starting the summer field season with LPC. Eventually more than 200 million gallons escaped the blown-out well, the largest offshore oil spill in U.S. history. Capped in July, the well was permanently sealed in September, just as loons across North America were beginning their fall migrations. Most of them–roughly 70 percent of the world’s common loons–were headed to the Atlantic and the Gulf of Mexico.
By fall, we’re calling the young loon “the juvenile.” Bigger than its mother and almost certainly a male, he badgers his parents for food. Nighttime temperatures dip toward freezing. We close the windows and add blankets to the beds. One morning in early October, I walk down to the pond with our son, scan the water, and realize that the adults have gone.
Our juvenile sulks, or so it looks to me, off in a far corner of the pond. His task now is to make the transition from water to air and to find his way to the coast. Over the next weeks, we see him struggle a few times and get briefly airborne, only to drift back to the water. It must be hard to develop the strength–and possibly the nerve, too–that will lift you away from all you’ve ever known.
The days grow shorter and colder. Our daughter catches me on the dock one afternoon, yelling across the pond at the young loon, “Get out of here!”
At the end of the 2010 field season, I’d spoken to Tiffany Grade, LPC’s field biologist for Squam Lake. Squam nests had again failed, one after the other. What most bothered her, she said, was one particular–and preventable–death. A male with a chick had been captured for banding and routine testing and was discovered to have elevated levels of lead. Attempts to recapture the male proved unsuccessful. A territorial battle ended with the weakened male beached on shore, and its chick, hatched the day before ours, killed by the attacking loon.
At Tufts, Mark Pokras performed a necropsy on the dead adult and found a fishing jig, made of lead, legal size. “That lead jig killed two loons,” Grade said.
In the end, only two chicks survived to fledge on the big lake. Elsewhere around the state, results were slightly better. But on Squam, once again, every individual mattered.