Hi! My name is Larry Neel, and I am a nongame biologist for the Nevada Division of Wildlife (NDOW). When most people think of Nevada one of the last things that come to mind is water, so Nevada is probably one of the last places a person would come to look for common loons! This may surprise you, but I want to share with you a discovery we have made of a large migration of loons that "refuels" at Walker Lake on their long journey north.
Walker Lake is a large desert lake 12 miles long and 6 miles wide situated at the eastern foot of the Wassuk Range, about 5 miles north of the small town of Hawthorne, Nevada. (See if you can find it on a map.) The lake serves as the terminus of the Walker River, which flows some 154 miles from the eastern slopes of the Sierra Nevada. Walker Lake is rich in fish life--Lahontan cutthroat trout, tui chub, and Tahoe sucker. The cutthroat trout is a game fish highly sought after by anglers. Tui chub and Tahoe suckers are nongame fish that serve as a food source for the trout and for thousands of fish-eating migratory birds, including common loons.
Starting about April 1, common loons, on migration from their wintering grounds off the coast of southern California to breeding sites yet unknown, begin to arrive at Walker Lake to build up their fat reserves for the next leg of their journey. By April 15, loon numbers have increased to 700-1,000 birds on the lake. The build-up of migratory birds at a site during migration is called 'staging'. After reaching these concentrations, departure occurs fairly rapidly and by May 1 nearly all the loons have left Walker Lake.
In the fall, the loons begin to arrive at Walker Lake around October 1, and stay until mid-November. Fall concentrations tend to run higher than in spring, and counts commonly go over 1,000 in mid-October.
It is believed that a combination of factors contribute to Walker Lake's attractiveness to migrating loons. One factor is its location. If you draw a line from say, Monterey, California to Yellowstone or Grand Teton national Park, that line would fall directly over or very near to Walker Lake. Although no banding studies have been conducted to verify this, biologists suspect that birds once thought to have migrated in the fall southeast from Montana, Wyoming and some of the central prairie provinces of Canada to winter in the Gulf region may in fact be migrating west to the California coast to winter. these birds find Walker Lake a very welcome stopover on their long, arduous journey.
Another important aspect about Walker Lake is its forage fish productivity. Using population estimation techniques such as netting and creel census, biologists estimate about 4.4 million tui chub in the lake. The overwhelming majority of chub and suckers are available to the loons as a food source. Walker Lake is only 90 feet deep at its deepest point, so all the lake is accessible to diving loons. Its water is relatively clear, which facilitates the loon's sight-hunting method. All these factors together add up to a loon "fish-a-rama" in the middle of the Nevada desert.
On April 12, my colleague John Elliott, NDOW fisheries biologist responsible for Walker Lake and I will be conducting our spring water bird census. We count common loons, double-crested cormorants, western and Clark's grebes, and American white pelicans using our binoculars from a 16-foot boat. We run three or four transects up and down the lake, making sure our transects are far enough apart that we do not double count birds.
On April 22, NDWS, the Lahontan Audubon Society and the Mineral County Chamber of Commerce will host the sixth annual "Walker Lake Loon Festival". Thee birds are decked out in their stunningly beautiful plumage and, if we are luck, they keep contact with one another with their 'tremolo' call. This year we have the extra special treat of having ms. Judy McIntyre of Utica College as our guest. She is a well-known biologist who has done considerable research on common loons and has published in magazines like National Geographic and written a book of her own about loons. We hope you will be thinking about us as we celebrate this age-old natural event. Thanks!
Larry Neel Nevada Division of Wildlife