The stats read like some sort of apocalypse.
The summer and fall of 2012 was also a terrible year for avian botulism, says Damon McCormick, a researcher and co-director of the Upper Peninsula's Common Coast Research and Conservation, a nonprofit that focuses on the study of common loons. More than 1,500 loons washed ashore just in the 70-mile stretch of Lake Michigan shoreline that is actively monitored.
But that could be just a fraction of dead loons, says McCormick.
The nonprofit oversaw some of the monitoring of beaches for avian botulism, but that accounted for only 13 percent of the northern Lake Michigan shoreline. McCormick estimated, based on the number of loons they found, that upward of 3,000 died in 2012, just in the northern third of the lake.
Many, or most, of these weren't Michigan loons. The fall – when loons and other waterfowl seem hardest hit – is a time of migration for waterfowl, and birds from Wisconsin, Minnesota and Canada use the Great Lakes as a corridor. That's part of the problem. Birds who otherwise might not land in the Great Lakes have to funnel through the area on their migration routes, and that puts them directly into harm's way.
Even if not all of the thousands of birds are Michigan loons, researchers are worried. With Michigan's loon population at about 900 nesting pairs, several years of tough botulism outbreaks could affect the state population.
"It's sobering to see the number of loons that have been involved with over the years," said Tom Cooley, wildlife biologist and pathologist with the Michigan Department of Natural Resources.
"How are we going to understand this substance?"
An answer for avian botulism might be a long time coming. The botulinum toxin and the bacteria, Clostridium, that produces it are difficult to research for a host of reasons, said Lafrancois. First, the Great Lakes are vast, providing a difficult backdrop for research. Wind, time, temperature, water and water currents are all elements researchers have to battle when testing for botulism, and when collecting birds that they suspect have died from botulism.
Second, botulism itself is difficult to research. The botulinum toxin – as well as the Clostridium bacteria – are both regulated by the Centers for Disease Control's National Select Agent Registry. The agency has determined it, as a "biological agent," to pose a "severe threat to both human and animal health," according to the registry website.
Researchers are only allowed half a milligram of the toxin – the most toxic substance known to science, say researchers – in their labs. A half a teaspoon contains 2,500 milligrams.
Researchers also can't propagate the toxin, or have the bacteria that produces the toxin, according to the website.
"The irony is that botulism is along 500 miles of shoreline, and you can make it in your kitchen if you improperly can, but it cannot be experimented with in the lab," said Common Coast researcher Joe Kaplan. "How are we going to understand this substance and how this toxin works if we're not able to directly work with it?"
How the toxin kills
In a healthy bird, proteins travel though its body, telling the bird: lift your wing now. Hold your head up. Swallow.
But when a loon or other diving waterfowl ingests the botulinum toxin, that toxin also travels through the bird's body, cutting those proteins in half.
This paralyzes the bird and unzips its ability to fly, swim, eat or even keep its head out of the water.