Earth Almanac: May/June 2008

Herp-In-the-Box

Bitter is the heart that doesn’t soar at the sight of a box turtle ambling through new meadow grass or leaf-shaded woods. Now, recovered from winter dormancy, these gentle, gaudy reptiles, which derive their name from the hinged plastron that allows them to completely shut themselves into their shells, are getting about the business of procreation. The male—distinguished by a long tail and long foreclaws—circles his prospective mate, head high. He nudges her and bites at her shell. If she’s in the mood, he’ll mount her from the rear, inserting his hind claws between her carapace and plastron and hooking his tail around and under hers. There are two species of box turtle in the United States: the eastern (which ranges from Texas throughout the southeast and north to Michigan and Massachusetts) and the western, found west of the Mississippi to New Mexico and Colorado. Where the two overlap they sometimes hybridize. Box turtles can live for a century, but they reach sexual maturity slowly, and are extremely vulnerable to depletion. No turtle, especially a box turtle, whose home range may not exceed five acres, should ever be moved to new and unfamiliar territory. But all turtles should be rescued from busy roads. Make sure you place them on the side they were headed for, so they won’t immediately cross again.

No Escape

Where our southeastern coastal plain slouches into swamps, bogs, and wet prairies, otherworldly predators, sometimes a yard tall, are starting their eight-month hunting season. From southern Virginia to Florida and north to Mississippi, they sway in the wind like charmed cobras. They are yellow pitcher plants—carnivorous herbs that compensate for their nutrient-impoverished, usually acidic habitat by devouring insects. Now petals appear on leafless stalks, and glands pump out aroma attractive to pollinating insects but so reminiscent of cat urine that displays at flower shows have been moved to breezeways. Seeking nectar, victims venture down the pitcher’s throat, where a waxy secretion makes them lose their footing and stiff, downward-pointing hairs guide them lower and lower until they fall into a digestive stew of enzymes, bacteria, and a hemlock-like toxin. Save for pollinators that stay high in the reproductive parts and a few large insects, such as wasps, that occasionally chew their way out, there is no escape.

The Biggest Bears

Whatever you learn about the taxonomy of brown bears is likely to be rebutted by your next source. To Americans and Canadians, “brown bear” means a coastal grizzly grown to enormous size on a diet of salmon and other rich protein sources such as whale and seal carcasses. Elsewhere in their range—Russia, France, Spain, Italy, Greece, India, Pakistan, Japan, Korea, China, Mongolia, Syria, Iraq, Iran, and Turkey—“brown bear” means Ursus arctos, of which the grizzly, having crossed from Eurasia on the Bering land bridge at least 50,000 years ago, is a subspecies. In North America there are only grizzlies, but the animals on Kodiak Island, called “Kodiak bears,” have been isolated there for 12,000 years, just long enough to be recognized by most taxonomists as a grizzly subspecies. Kodiak bears, which can weigh 1,500 pounds, are the planet’s largest land omnivores. Now, freshly undenned, they are prowling the beaches in search of carrion. Soon they’ll be feasting on the first returning salmon. In sparse inland habitat, a grizzly may need 300 square miles to make a living. On Kodiak Island, which sustains a healthy population of about 3,500 animals, it needs less than two.