Birds of the Basin
The Migratory Millions of Mono
As I write, the phalaropes--minus the few that foddered falcons--are 3,000 miles away in South America, where they are cavorting with flamingoes on saline lakes high in the Andes. Yet somehow the paths they travel, while beyond human design, are parallel with our own. They have as much right to be here as we do--not because they are useful or beautiful, but because they are kin.
David Gaines
Mono Lake, Autumn Equinox, 1987
MONO LAKE INTERNATIONAL AIRPORT
Despite Lee Vining's tiny little airstrip, the Mono Basin has probably the busiest international airport in California with millions of birds arriving and departing between mid-summer and fall. A vital stop on the Pacific Flyway, migrating Eared Grebes, Wilson's Phalaropes, and Red-necked Phalaropes are among the most common of the nearly 100 species of birds that are found around Mono Lake. Why Mono Lake? By mid-summer abundant alkali flies and brine shrimp provide an endless food supply for migrating birds (click here for a bird list). Stream delta, and near-shore wetland habitat also provide good bird habitat.
HIGH DESERT ROOKERY
If you visit a beach in California and you see a California Gull, there's a high probability it was born at Mono Lake. By late spring anywhere from 44,000 to 65,000 California Gulls arrive to breed on Mono's lesser-known islands. Mono Lake is home to the second largest California Gull rookery in North America (Great Salt Lake is the largest). The majority of gulls used to nest on Negit Island, the black cinder cone island to the north of Paoha. In 1979 water diversions lowered the lake level to a point where a landbridge emerged connecting Negit Island with the mainland. Hungry coyotes made easy prey of gull chicks, and the adults abandoned the island. Today the majority of California Gulls nest on the small islets neighboring Negit Island's north shore. A few gulls also nest on the Paoha islets, near Paoha's west shore. The gulls avoid Paoha Island entirely. As of 1999, with the rising lake, gulls began returning to Negit Island, their primary, native nesting grounds. Click here to read an article on the California Gull.
AN INCREDIBLE JOURNEY
Of all the birds that come to Mono Lake, the Wilson's Phalarope stands out as the hardiest traveler. These small shorebirds, not much larger than a fist, arrive at Mono Lake in mid-summer after breeding in the northern U.S. and southern Canada. At Mono Lake they molt their feathers and double their weight after several weeks. By the middle of September they have mysteriously disappeared. Leaving in stages during the cover of darkness, they depart for a journey that takes them all the way to South America. The fact that these birds fly over 3,000 non-stop miles to South America is amazing enough, but what is truly astonishing is how fast these little birds reach their destination--an unbelievable 3 days!
OCTOBER CONVENTION
Move over Las Vegas! One of the greatest conventions in North America takes place on Mono Lake!
The Eared Grebe, a diving, duck-like bird that spends its entire life on water, arrives at Mono Lake in greater numbers than any other species. Aerial surveys have revealed 1.5-1.8 million birds on the lake in the fall--comprising a large portion of North America's population! Mono Lake provides a tasty staging area for these water-bound birds as they feast on brine shrimp. The grebes double, and in some cases nearly triple their weight after gorging themselves on shrimp (but isn't that what conventions are all about?). Many grebes end up getting too fat to fly, and must lose weight before departing for winter destinations.
THE FLYWAY CONNECTION
Mono Lake is a small, vital part of the big migration picture. Because large numbers of phalaropes, gulls and grebes depend on the lake, along with approximately 100 species of other birds, Mono Lake was designated as a part of the Western Hemisphere Shorebird Reserve Network (WHSRN). WHSRN is a collection of critical migratory bird habitats in North and South America. Birds like the Wilson's Phalarope depend on Mono Lake as well as Great Salt Lake, and a host of other lakes in South America for their survival. Mono Lake is twinned with Great Salt Lake in Utah and Mar Chiquita in Argentina because of their combined role in providing critical habitat for Wilson's Phalaropes. If you explore some of the less-visited stretches of Mono Lake during shorebird migration you may see for yourself the lake's importance to birds--American Avocets, Western and Least Sandpipers, Snowy Plovers, White-faced Ibises, Dowitchers, along with the occasional rare appearances of Whimbrels, Baird's Sandpipers, Sabine's Gulls, Black Terns, and Parasitic Jaegers.
WHERE ARE THE WATERFOWL?
The data is incomplete, but there is evidence to suggest that Mono Lake once hosted nearly a million ducks as recently as 1948. Nearly 40 years later in 1986, only 14,000 could be counted. Water diversions to Los Angeles radically changed waterfowl habitat in the Mono Basin. This combined with loss of habitat throughout North America helped reduce waterfowl populations over the decades. Restoration of waterfowl habitat in the Mono Basin may bring increased numbers of migrating ducks, but will we ever see the numbers of the past? Today you can still see a wide variety of waterfowl at Mono Lake, mostly in the fall. Canada Geese, Mallards, Northern Shovelers, Northern Pintails, Gadwalls, Ruddy Ducks, Cinnamon Teals, and Green-winged Teals are locally common around the lake. If you take some time to explore off the beaten path you may encounter the occasional Bufflehead, Lesser Scaup, Snow Goose, or even migrating Tundra Swans in the late fall.
OTHER BIRDS
The Mono Basin is home to millions of birds representing over 300 species. Most are migratory, and over 100 species nest here as well. The Mono Basin watershed has a variety of habitats, and each supports its own collection of bird species--as well as birds commonly seen throughout the basin. Green-tailed Towhees can be seen in the vast sagebrush plains around Mono Lake. Yellow Warblers can be found along the creeks, with the densest population in the state in the Rush Creek Bottomlands. Osprey are fish-eating hawks and can be seen fishing in freshwater streams and lakes and nesting on tufa towers in Mono Lake.
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