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Earth Almanac

Trunk Show
Snowbirds
Witch’s Hair
Spoon-Feeding
Tough Berries
Snow Strutters

Trunk Show
From California to Baja, the world’s largest seals are hitting the beaches to mate and give birth. The mature male’s inflatable, trunklike proboscis—which overhangs the lower lip by about eight inches and gives the elephant seal its name—amplifies the outlandish snorts and grunts made during combat for harem supremacy. Much of that combat is bluff and bluster, but some is real, with nasty though seldom fatal wounds delivered by canine teeth. As with many animals in which mating dominance is established through fighting, males are much larger than females, occasionally reaching 5,000 pounds. Females give birth a few weeks after the males’ arrival. Elephant seals come ashore each year to molt their fur and epidermis. This leaves them vulnerable to cold, so they don’t enter the water again until they are reclad, a process that can take a month or more. The annual molt makes the elephant seal the only mammal to undertake two migrations a year—from its feeding grounds in the north Pacific to its breeding habitat in Southern California and Mexico to molt, back to its feeding grounds, then back to Southern California and Mexico to breed.
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Snowbirds
Dark-eyed juncos—also called “snowbirds” because they waft south from boreal breeding grounds on the teeth of blizzards—are flooding fields, parks, and yards across the contiguous 48 states. The birds you see foraging in your yard are likely “yours,” because they usually return to the same winter habitat. In one experiment, nine of a dozen banded in a Massachusetts backyard were seen there the following year. Your flock, numbering as many as 30 birds, will form about a half-hour before sunrise, feed through the day, then disperse to roost about 45 minutes before sunset. Listen to their seemingly absentminded chips as they forage. And watch them as they raise and flash their tails to show dominance, hop, scrape circles in the snow, and perch like miniature “benders of birches” atop grass stems, riding them to the earth to feast on the seeds.
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Witch’s Hair
If you don’t believe in witches or if you don’t believe they’re beautiful, walk an ancient rainforest on a cloudless night anywhere from Northern California to Alaska. Having taken the form of old trees, these witches dance in the Pacific breeze, their long locks sending shards of moonlight shivering across the forest duff. Like many other lichens, witch’s hair, as Alectoria sarmentosa is called, is extremely sensitive to airborne pollutants, making long-term changes in its abundance an accurate indicator of air quality. Now, when ground forage is sealed under snow, this lichen becomes especially important to wildlife. Woodland caribou in particular depend on it to get them through the winter. In British Columbia it has been aptly described as the black-tailed deer’s “bridge to springtime.” Moose and mountain goats eat it, too. Witch’s hair provides food and cover for California and red-backed voles, which, in turn, help sustain spotted owls, great horned owls, saw-whet owls, spotted skunks, pine martens, short-tailed weasels, and long-tailed weasels. Cut-over forests—even when they return to climax condition—don’t sustain this rich diversity of life. Only in true old growth do branches continually fall to the forest floor, bringing with them this abundant winter feast.
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Spoon-Feeding
Birds have evolved all manner of bills—hooks, spears, nutcrackers, seed shuckers, straws, chisels, shears, hammers, tongs, and even spoons. The roseate spoonbill, the New World’s only spoonbill species, looks as if the tip of its bill had been squashed by a garage door. Catching prey is a time-consuming process in which the bird sweeps its bill over the bottom and snaps shut its nerve-rich mandibles when it feels fish, mollusks, or aquatic invertebrates. Spoonbills live along the Gulf of Mexico’s entire coastline to Central and South America and the West Indies. In our Florida population breeding is already under way. Elaborate courtship displays include bill clapping, dancing, presentations of nest material, and flights in which the tongue is extended and the orange throat skin exposed. Especially during nesting the roseate spoonbill seeks the company of other species—in Florida, herons and wood storks; in Texas and Louisiana, gulls, terns, and herons. Audubon may have had it right when he theorized “that the keen sight and vigilance [of these other species] are useful to it in apprising it of danger.” Plume hunters nearly drove roseate spoonbills to extinction, but the feathers became unpopular because their vibrant pink color faded rapidly.
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Tough Berries
January is too cold for insectivorous birds and their prey. So what bonanza could those excited tree swallows have stumbled on as they dip and dive gull-like around that shrub? Like so many other birds, including grouse, quail, turkeys, woodpeckers, pheasants, and countless songbirds, they’re feasting on bayberries. You’ll find bayberry in the East—the northern species, from Newfoundland to North Carolina; the closely related southern species, from New Jersey to Florida. The two readily hybridize, so in overlapping range, identification can be difficult. The berries’ aromatic wax coating, used to make candles, has given the plant its alternate names of waxmyrtle and candleberry. (Make your own candles by boiling the berries and skimming the wax.) Because few shrubs are as resilient to harsh weather and poor soil, bayberry is ideal as a windbreak, hedge, or soil stabilizer. Besides providing winter food for birds, the leathery leaves, retained long into winter, provide excellent wildlife cover. You won’t get berries unless you have at least one male shrub, and since it’s impossible to determine sex when they’re immature, you should plant several.
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Snow Strutters
Joni Mitchell was stretching it some when in her classic ode to winter, “Urge for Going,” she sang: “All that stays is dying, and all that lives is gettin’ out.” Creatures like the snow scorpionfly—a harmless insect that gets its name from the male genitalia, which resemble a scorpion’s tail—stay for the precise reason that so many species that would otherwise eat them are “gettin’ out.” You’ll find these ancient, flightless members of the order Mecoptera most anywhere winter is long and white. Look for them on mild days when they tunnel up through the snowpack and strut around the surface on stilt-like legs that protect their bodies from the cold. Anti-freeze in their blood provides further protection. The female’s wings have shriveled to mere pads. The male’s, narrow and spiny, are vestigial, too, but far from useless. With them he clasps his mate and holds her on his back during copulation. As the sun and temperature sink, snow scorpionflies tunnel back to their mossy grottoes, where they find warmth and secure shelter for their fertilized eggs.
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