By Eve Broughton
Jack rabbits are crazy; why else would they run ahead of a car for three-fourths of a mile without turning off the road? Maybe they just like a good run, and they are built for it, able to go as fast as 35 mph. They have very long hind legs and can bound 20 feet.
Lepus californicus ranges from Texas and Mexico to Oregon and California. We tend to associate them with arid regions, but they are present and happy here.
Here too, is the cottontail, aka brush rabbit, Sylvilagus bachmani. But while the hares (jack rabbits) like a moderately open situation with a mixture of grasses, forbs, and shrubs, the bunnies (cottontails) prefer dense brushy cover or thick grass (in which they make runways) and rarely come out in the open. However, cottontails have been seen frolicking in a meadow in the moonlight. Perhaps they prefer fun to run.
Lepus is a nocturnal feeder, eating a varied diet of whatever is available at the time: grasses, forbs, twigs, and buds. Their range may be over half a square mile in some places, but they do not migrate. Nor do they make nests, using shallow depressions beneath shrubs and small trees for cover, warmth, shade, and giving birth.
The hare breeding season runs from late January to August, producing three to four litters a year. After a gestation of 41 to 47 days, the three or four young are born fully furred with their eyes open, and are mobile soon after birth. A good thing that is, because they are nursed for only two to three days.
In contrast, cottontails can have up to five litters a year with one to seven young per litter. The gestation time is 22 days, and the young are born hairless.
Both have light undersides but the jack rabbit is darker on top, with black-tipped ears and tails. It is also twice as large, with proportionately longer legs and ears.
Nor does the cottontail have as wide a range, S. bachmani being limited to Oregon and California. There are many other species and genera of hares and rabbits across the Northern Hemisphere. It is thought they evolved in Asia during the Paleocene from an ancestor common also to rodents and elephant shrews.
Hares and rabbits, and their kin the pica, (all lagomorphs) are not rodents. Their skulls can be easily distinguished from rodents by the dentition. While both have large ever-growing gnawing incisors, lagomorphs have four, not two, upper incisors. The second pair is smaller and found behind the front pair.
Lagomorphs have more, and larger, cheek teeth, which are ever growing. Rodent molars are small, and not ever growing, probably because the rodent diet of seeds, grains and tubers is high-energy and need less chewing than the grasses that lagomorphs prefer. Grasses contain silica, which is highly abrasive. Also, rodents do not have milk teeth: lagomorphs do, although these are lost in utero or soon after birth.
Eve Broughton lives in Whitethorn, and was educated at UC Berkeley.
This article is part of a series about natural life on the Lost Coast, sponsored by the Lost Coast Interpretive Association, which may be contacted at email@example.com. For photos, educational information and news about the Lost Coast, please visit the Lost Coast Interpretive Association’s Facebook page. https://www.facebook.com/pages/Lost-Coast-Interpretive-Association/241253955966296.
PHOTOS COURTESY OF KIM CABRERA
1. Blacktailed jack rabbit
2. Brush rabbit cottontail