Lake Champlain’s status as a Great Lake lasted only briefly in 1998. But the skinny, 400-foot-deep body of water that forms Vermont’s western border has always been “great” in one way: It has an unusually large drainage basin. As botanist Mike Winslow points out in his informative guide, Lake Champlain: A Natural History, the lake’s tributaries meander from as far as 120 miles away.
Environmental awareness is the raison d’être of Lake Champlain. Prefaced by Ripton-based activist-writer Bill McKibben, the book is published by the Lake Champlain Committee, a lake stewardship nonprofit based in Burlington and operative in both Vermont and New York.
Winslow’s book is an enjoyable read. LCC’s staff scientist since 2001, the author has genuine love for the lake’s peculiar ecology and a flair for explaining its phenomena clearly. The Vergennes resident has been honing his presentation style for the last eight years in his monthly LCC column “Lake Look,” familiar to readers of North Avenue News and other local papers.
Winslow begins by condensing 500 million years of lake formation into a few succinct pages. Calcium-rich coral reefs from that period, still visible in Isle La Motte, helped create a soft limestone foundation. Eventually, shifting tectonic plates formed the graben — German for “ditch” — that would contain, in succession, Lake Vermont, the salty Champlain Sea and, as of 10,000 years ago, Lake Champlain.
Chapters on the lake’s animals, plants and physical phenomena make Lake Champlain an eye-opening primer for the lay lake user. The kayaker who has passed large squadrons of double-crested cormorants will learn that population-control efforts to oil the birds’ eggs in 1999 merely caused them to move to deeper waters, where they eat even more fish. Anglers dismayed to discover sea lamprey wounds on their catch will read that those jawless suckers are native; it’s the lake trout that are stocked, having disappeared from these waters in the late 19th century. A late-season jogger on Burlington’s bike path might be surprised by the water’s rank smell; in autumn, Winslow informs us, the temperature of the water’s upper layer equalizes with that of its depths, causing a turnover of the stagnant lower layers.
Winslow, who earned a master’s in botany at the University of Vermont, ends by diagnosing the current state of the lake’s health: It’s over-brimming with nutrients. Excess phosphorus is the primary culprit, he says, and its major source is not agriculture but developed — i.e., paved — land. One look at Burlington’s suburbs from Interstate 89 suggests that the amount of surfaced land in the Champlain drainage basin is only going to grow.
Winslow concludes on a hopeful note — individuals can still make a difference, he says. Scoop your poop, wash your car away from pavement — and check out the Lake Champlain Committee website for more tips.
Lake Champlain: A Natural History by Mike Winslow. Lake Champlain Committee, 150 pages. $18.95.
Winslow speaks on “Lake Champlain in Winter” on February 19 at the Ilsley Library, Middlebury, 7 p.m. Free and open to the public. Info, 388-4095.