Earth Almanac: October/December 2002

Catlike Cat Eaters

Throughout our northern states, strange beasts are being sighted in town and country, often in trees. They are dark, almost black, with the face of a cat and the body of an otter. Adult males may be three and a half feet long and weigh 20 pounds, but they look much bigger than they are—the size of a dog or cougar, according to wide-eyed suburbanites. Winter is the best time to find fishers—a.k.a. "fisher cats"—because hardwood foliage no longer obscures your view, and tracks are visible in the snow. Fishers, giant weasels that were nearly trapped out of existence in the contiguous states because of their luxuriant fur, are making an impressive comeback throughout their range. They're even colonizing new range to the south and northwest. Fishers are one of the few creatures that regularly prey on porcupines, biting them repeatedly in the face, then flipping them on their backs to expose the quill-less belly. They are also fond of house cats, providing yet another good reason to keep Tabby indoors. 

Merry From Berries

Cedar waxwings, named for the waxy red substance exuded from shafts of secondary feathers, disperse color and merriment across winterscapes through most of the temperate 48 states. Like carolers seeking wassail, they burst into berry-laden shrubs, gorging on the frozen fruit until it protrudes from their beaks and they have difficulty getting airborne. Sometimes a berry will be passed from beak to beak, down a long row of birds, then back again, until someone finally swallows it. If berries are fermented, the birds may become so intoxicated that they stumble along the ground and you can pick them up and stroke their jaunty crests. The position of this crest expresses every emotion—fear, when flat; comfort, when low; surprise, when erect. Roving flocks are frequently accompanied by wintering robins and bluebirds and, now and then, a Bohemian waxwing—significantly larger and with cinnamon instead of white on the undertail. The regeneration of forests and the widespread plantings of fruit-bearing ornamentals have sharply increased cedar waxwing populations, especially in the East. Recently, some birds have developed orange instead of yellow tail bands, a change apparently wrought by pigments in the alien honeysuckle berries they've been eating.

Survival of the Coldest

Frigid winters have their compensations, among them common redpolls—hardy finches that arrive on Arctic blasts from boreal realms to take up seasonal residence as far south as New Jersey and Iowa. No other northeastern bird has the redpoll's red cap and black chin, and no songbird anywhere has been seen to survive colder temperatures. Maybe its most important adaptation is a croplike structure in which the birds store seeds to sustain them through extended blizzards and long northern nights. When temperatures drop, stock a feeder or two with thistle or shelled sunflower seeds. But if you find yourself hosting redpolls, don't just watch them from indoors. Their normal winter range is too harsh for most humans, so when these birds visit the United States—often in flocks of 100 or more—you can approach them easily. Note their synchronized movements while rising, perching, and feeding, as if they were being directed by some telepathic drill sergeant. 

Green Gems in Winter

America pays little attention to ferns, particularly in winter, when most are brown and withered. But early European settlers had a passion for them, especially Christmas ferns, which remain green all year and which got their name because they were favored for yuletide decorations. None of our evergreen ferns is larger, and none has such deep-green, highly polished fronds. Christmas ferns abound in the eastern half of our nation, and it's okay to pick or transplant a few. They're an excellent addition to gardens because deer won't eat them. During a thaw, when the snowpack slumps, look for the leathery, lance-shaped fronds lying flat on the ground. As poet-botanist W. N. Clute put it: "No shivering frond that shuns the blast sways on its slender chaffy stem; / Full veined and lusty green it stands, of all the wintry woods the gem." 

School's Out

With the line storms of late autumn and early winter, Atlantic menhaden—herringlike fish that spawn at sea—move in colossal schools out of Northeast bays and estuaries, setting a course for their offshore wintering grounds south of Cape Hatteras, North Carolina. On still days, watch for what looks like rain squalls sweeping across the ocean. If you are in a boat or standing on a dock or a bridge, you may see silver, oval fish, 4 to 15 inches long, streaming by with their mouths open and gills flared as they strain out phytoplankton with their gill rakers. Often a school will be attended below by crashing, boiling striped bass and bluefish, and above by screaming, diving gulls and terns—all swilling protein for their own southbound migrations. Sometimes the bluefish push menhaden onto beaches, where they pile up in windrows miles long and up to three feet high. Tuna, seals, porpoises, and sharks follow the orgy, consuming the menhaden as well as the bass and the blues. But by far the most efficient predators of menhaden are humans, who catch them in purse seines. During the past five years annual U.S. landings have averaged 227,000 metric tons—more than for any other fish save Gulf menhaden (a closely related subspecies) and Alaskan pollack. Most menhaden are rendered into animal feed and additives to plasticizers, resins, lipstick, shortenings, and margarine. Always the menhaden defend against the slaughter with a fecundity that defies human imagination; and while there can be sharp population swings, they appear to result only from natural causes. In 2002 the National Marine Fisheries Service reported the highest spawning stock since the early 1960s. 

Punctuation in Flight

'Tis the season when even lepidopterists forget about butterfly watching, and that's why finding winter butterflies can be so much fun. Species you'll meet are pretty much limited to overwintering anglewings, most notably the question mark, usually brighter than the summer form and named for the silver punctuation mark on each underwing. East of the Rockies (save the extreme northern range, too cold for hibernation and reinvaded by migrating adults each spring) you may encounter a flying question mark on mild winter days. Check woodpiles and outbuildings, where they briefly emerge from hibernation. These butterflies rarely feed on flowers, preferring rotten fruit, carrion, dung, and sap. You may be excused if you'd rather not set out the first three of these food sources. Break off a few birch or maple branches and you may find a question mark sipping the sugary flow.