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Earth Almanac

Mad Hares
Splendor in the Grass
Twist and Sprout
What Lurks Below
Pretty Poison
Sun-baked Lizard

 

Mad Hares
March hares may be “mad,” but the hares of the Great Basin and northern Great Plains are that way from February through July—never more so than in May, when mating peaks. Having shed their white winter pelage for brown and gray, male white-tailed jackrabbits abandon their solitary lifestyles, assembling in groups of three to five. A group will pursue a female, charging and jumping at her and fighting furiously among themselves, though almost never causing visible injury. When she has chosen her partner the couple will rise on their hind feet and spar with their forelegs, then copulate. Meanwhile, females impregnated earlier in the season are delivering young—usually four or five, born fully furred and open-eyed. Even before they’re weaned, their mother may be pregnant again. White-tailed jackrabbits are capable of bursts of 40 miles per hour and can leap as high as 12 feet. Eyes, set high on their heads, afford an almost 360-degree field of vision. And enormous, richly veined ears provide a cooling system as well as early predator detection. Like other members of the hare–rabbit family, white-tailed jacks re-ingest their soft fecal pellets, sending vegetation through the digestive system twice, thereby improving nutrient intake. In arid regions, where water conservation is a priority, the final, harder scats are dry.

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Splendor in the Grass
Throughout most of the United States except parts of the arid West, grasshopper sparrows are courting with low, fluttering flights, sometimes accompanied by song. The grasshopper sparrow is atypical in all sorts of ways. For one thing, it is stockier than most sparrows. For another, it eats more insects, and while it rarely passes up a grasshopper, it is named for its distinctly un-sparrowlike vocalization—a buzzing trill reminiscent of grasshopper music from a summer meadow. Also unlike most other sparrows, males have two different songs, both of which are sometimes heard at night. One song, territorial, consists of several staccato notes followed by the grasshopper buzz. The other, used primarily to establish and maintain the pair bond, is a set of squeaking notes of varying pitch. A descending trill is uttered by both sexes to announce arrival at the nest, a covered cup with a side entrance hidden in the grass. You will almost never flush a female directly from her eggs. But you might glimpse her as she dashes rodentlike through the grass, eventually taking wing and frequently feigning injury. Because so many of our grasslands have been developed, grasshopper sparrows are thought to be declining at a rate of roughly four percent a year. But so expansive is their range that they are classified as a species of “least concern” by the International Union for Conservation of Nature.

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Twist and Sprout
In the rich, well-drained high country and piedmont of our southern Appalachians, mountain magnolias are opening their enormous white flowers—some six inches across. So desperate for sunlight are these hardwood trees that their branches and boles are often contorted, having sprung from leaders that constantly twist to take advantage of openings in the forest canopy. For this reason, and because the wood is soft, mountain magnolias have little value as timber or firewood, but they greatly benefit wildlife. Injuries to the fragile bark often result in rotting wounds easily exploited by cavity nesters, and in autumn the scarlet, thumb-sized fruits are relished by many kinds of birds and mammals. Magnolias are an ancient genus thought to have evolved before bees appeared, which may explain why they’re pollinated by beetles. The sex organs of magnolias are tougher than those of most flowering plants because beetles, which chew and crawl and are generally clumsy, would otherwise destroy them.

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What Lurks Below
If you thought griffins—eagle-beaked lions capable of flight—were mythical, you weren’t looking closely enough. In late spring, most anywhere in the United States where dirt or sand is loose, warm, and dry, antlions—larvae of large, lacy-winged insects that resemble damselflies save for their clubbed antennae—are lying in ambush. Now, in their flightless form, they live at the bottom of conical pits, an inch or two across at the top, that they’ve excavated by inscribing concentric and ever-deeper rings. The antlion’s alternate name, “doodlebug,” comes from the rambling, doodle-like patterns it leaves as it crawls around looking for the right place to dig. It waits just under the point of the inverted cone, sometimes with its sickle-like mandibles showing. When an ant or small insect stumbles into the pit, the antlion kicks up sand or dirt, causing miniature landslides that send the victim tumbling to its doom. When you find a cone, tickle the sides with a pine needle and watch the puffs of material thrown into the air by the deluded antlion. Antlions go dormant when disturbed, so they’re easily caught. Keep one in a lidless jar full of sand, and feed it ants. Eventually it will pupate, emerge, and lumber clumsily into the air.

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Pretty Poison
Even before grass appears, open woodlands, plains, and railroad right-of-ways in our upper Midwest and south to Texas brighten with sundry shades of indigo. In scattered clusters and vast carpets, prairie larkspur is opening its blossoms to the late-spring sun and bumblebee pollinators. A mature plant may stand close to four feet high and support as many as 30 flowers on a 10-inch spike. The name larkspur comes from the projection at the back of each flower that resembles the hind toe of a bird. Prairie larkspur belongs to the family Ranunculaceae, named for Ranunculus—a figure in Greek mythology noted for his colorful clothing. Even more impressive was his singing, which dazzled everyone, especially himself. One day, while crooning to some wood nymphs, he became so excited by his own voice that he expired in the middle of the performance, whereupon the magician-musician Orpheus converted him to a flower. Prairie larkspur is unpopular with ranchers because it’s deadly to cattle. But, at least in earlier times, it partially redeemed itself by killing lice when afflicted ranchers rubbed it into their hair.

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Sun-baked Lizard
In our Mojave, Sonoran, and Colorado deserts, long-tailed lizards a foot long or more are breeding. Now they’re sometimes seen foraging in pairs—presumably as mated couples. This may indicate pair bonding, unusual among reptiles. Look for desert iguanas during the day in and around creosote bushes. Even when the temperature hits 113 degrees Fahrenheit they’ll be active. No other North American lizard is as tolerant of heat. Desert iguanas use abandoned mammal burrows for refuge and nesting sites, modifying them by excavating a central chamber and sealing the entrance with sand. The three to eight eggs laid in the summer will hatch in September, and when the young emerge the adults will become less active, perhaps to reduce competition for food. Their diet consists of flowers, buds, fruits, leaves, mammals, lizards, and feces. Desert iguanas secrete a fluid from their thighs that fluoresces in wavelengths they can see, suggesting an adaptation for perceiving others of their species.

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