It's spring, and that means the animals of the world are in motion again — flying, swimming, running and crawling to their summer homes and breeding grounds. The Nature Conservancy is celebrating this annual pageant of nature with a listing of the “Top Five Must-See Migrations” in Wyoming.
“Whether one is witness to the elevational movements of large mammals or the intercontinental flights of birds and butterflies, migrations expose the less visible networks that connect places to each other,” explains Trey Davis, the Conservancy’s Northern Wyoming Stewardship Coordinator. “Migrations highlight the links, limits and adaptability of the cast of characters who share the land.”
In southwestern Wyoming, one of the longest remaining overland mammal migrations occurs each spring and fall. Pronghorn, which can run at speeds up to 65 miles per hour, travel more than 150 miles from Grand Teton Park to the upper Green River Basin. In the spring, they make their return north to the Park from the grasslands and sagebrush where they’ve waited out the deep winter snow, bringing with them newly born young. The Wildlife Conservation Society formally named this trek the “Path of the Pronghorn” and helped make it the first federally protected wildlife migration corridor.
As the snow begins to melt and grasses turn green, herds of elk numbering in the thousands return to the high country of Wyoming’s mountain ranges. Yellowstone National Park in northwest Wyoming is perhaps one of the best places to view these herds in their summer range. But, as the harsh cold days of winter descend, so too do these animals. During the fall months, spectacular elk migrations occur in places like: Carter Mountain and Pitchfork Ranch, Tensleep Preserve, and the National Elk Refuge in Jackson.
The annual migration of North America’s monarch butterfly is an amazing phenomenon—like birds, the monarch makes a north-south migration. Relying on environmental cues the monarchs head south, flying as far as 3,000 miles to reach their winter home. But no single individual makes the entire round trip. Female monarchs deposit eggs for the next generation during these migrations, so second, third and fourth generations make the return trip north in the spring.
Monarchs typically begin to arrive in Wyoming in June where they will spend the warm summer months. Finding these lightweight flyers means finding out where milkweed occurs—milkweed is the only type of plant that monarch caterpillars can eat. When cold weather appears, the monarchs begin their winter migration towards Mexico and the California coast. But scientists still have much to learn about this unique migration and are continuing research and tracking projects.
This species has one of the longest hummingbird migration flights, flying up to 3,000 miles from its breeding range in Alaska to wintering grounds in Mexico. In the spring months, between February and May, the rufous hummingbird travels north to summer breeding grounds in Wyoming and other parts of the northern U.S. These small, pugnacious birds find comfort in flower gardens, hummingbird feeders and wildflower meadows throughout the state’s mountain ranges, particularly in western, southwestern and southeastern Wyoming. The species is known for its bully-like behavior at bird feeders and flowers, chasing other hummingbird species (and the occasional tanager or oriole) away to keep the food all to itself.
Spring in eastern Wyoming sees the return of the graceful American avocet. This long-legged shorebird uses shallow freshwater wetlands as breeding grounds, laying up to 4 eggs per nest. American avocet chicks leave the nest within 24 hours after hatching, and day-old chicks can walk, swim and even dive to escape predators. Come fall, these birds take flight once again to winter in the warmer climes of the southern Atlantic and Pacific coasts of Mexico and the U.S.January 07, 2011