Reptile and Amphibian CrawlIn March and September, rangers in the Shawnee National Forest in Illinois close three miles of Forest Road 345 to protect 50 species of reptiles and amphibians, from stinkpot turtles to southern leopard frogs, as they crawl 1,200 feet between the 800-acre LaRue Swamp and hibernation spots below the Pine Hills bluffs.
Eel OrdealEels from eastern Canada and the United States swim thousands of miles across the Atlantic each year to spawn in the warm waters of the Sargasso Sea. Then they die. Their young drift back to North American streams, where they huddle in slippery masses several miles long.
Garter-Snake OrgySome 20,000 red-sided garter snakes slither out of the grasslands and into warm, 12-foot-deep limestone pits near Narcisse, Manitoba, each September. In April, the garters coalesce in a mass of writhing, mating serpent flesh before heading back to the Canadian prairie.
Lemming UprisingEvery three to four years, when food supplies dwindle, the lemmings of Norway's coastal mountains storm from their burrows in gangs. The rodents scamper down roadways, blitzkrieging cities and forests.
Crab CarnivalIn November and December, millions of red crabs overrun 52-square-mile Christmas Island in the Indian Ocean. They crawl up to nine miles from their rainforest homes, swarming through towns and getting into cupboards and cookie jars before depositing their eggs near the sea.