The turning of the year offers people and creatures alike the chance to experience more enjoyable weather. Summer’s hot, dry heat becomes winter’s freezing chill, and while some of us are lucky enough to vacation away from our weather woes, creatures in the animal kingdom have fewer options. They often can’t hit the slopes in the summertime or go on island getaway cruises in the winter. However, several species do travel great lengths for the perfect climate.
Mexican Free-Tailed Bats
Free-tails spend the warmer months in widespread habitat that encompasses most of the southern half of the U.S. As northern cold fronts drive temperatures down, they migrate together in massive groups - seriously massive groups! These bats can roost in colonies of several million individuals, so when they take wing together, they darken the skies with their sheer numbers, their wings creating a sound like the rushing thunder of whitewater as they fly for friendlier skies. The density of these colonies have also been known to show up on Doppler radar as an incoming storm system, so meteorologists have learned to see the difference. The longest recorded migrations for Mexican free-tailed bats have seen them overwintering more than one thousand miles south of their summer caves.
Monarch Butterflies
The striking black-and-orange coloration of the monarch butterfly makes it a favorite of collectors, but its beauty is temperamental. Monarchs aren’t built to survive the harsh, colder winters of their favored summer quarters in the Northern Hemisphere. Those living east of the Rockies will begin a southern migration of up to 3,000 miles toward overwintering sites in Mexican pine-oak forests starting in August, while their western cousins will seek out the coastal microclimate of Southern California’s stands of eucalyptus and Torrey pines.
Humpback Whales
Their enormous size daunts us. Their mysterious, haunting songs captivate us. Turns out, though, humpback whales are very much like us in at least one respect: they seek out heat after a long, cold season. These gargantuan creatures like a spot of tropical warmth after a chilly summer in polar waters and they’re willing to go to great lengths to get it. Some pods have it easier than others, journeying a cool 6,000 miles round-trip between Alaskan coastal waters and Hawaiian ones, but others travel as many as 5,200 miles in a single leg from their summer feeding grounds in Antarctica to their winter nurseries near Costa Rica. The record? A whopping 11,706 miles between the Antarctic Peninsula and American Samoa.
Arctic Terns
Imagine being so enamored of the days of longest light that you were willing to travel from one pole to the other, constantly in pursuit of that unbeatable summer sun. Is a journey with a minimum distance of 12,000 miles one way worth getting two summers every year and more daylight than any other living creature? If you said yes, you might be an arctic tern, an unassuming bird of grey and white plumage that stands about a foot tall and has a wingspan of less than three feet. These birds have what’s called a continuous circumpolar migration pattern: they spend their lives travelling between Earth’s northern and southern poles, racking up some 44,000 frequent flyer miles every year.
More than a million wildebeest and zebra cross annually the border between the Tanzanian Serengeti Plains and the Kenyan Masai Mara National Reserve in search of fresh grass and water in what is called 'The Great Migration.'(PEDRO UGARTE/AFP/Getty Images)
The Great Migration
Every year, upward of two million animals migrate in a loose clockwise pattern between the Serengeti National Park in Tanzania and the Maasai Mara National Reserve in Kenya, with wildebeest at the helm and herds of zebra, gazelle, eland and impala in close proximity — and of course, big predators like lions not far behind. The wildebeest follow the rain responsible for their food and water, so no two migrations have the exact same timing, and as the herds are continually in motion it’s tough to pinpoint a beginning or an end to the migration. Still, most say the migration begins with the calving of hundreds of thousands of wildebeest in the Serengeti. The herds travel west and north as their plains begin to dry out, crossing lakes and two major rivers en route to the Maasai Mara reserve; they then travel east and south again as the rains begin to fall again on the short-grass plains from which they began their journey. The whole trip is around a thousand miles, but with so much of the circle of life on display, it’s no wonder this event is called The World Cup of Wildlife.
No comments:
Post a Comment