Biology Reference
In-Depth Information
Natural-born killers: black-tailed rattlesnake swallowing a desert cottontail, Chiricahua Moun-
tains, Cochise County, Arizona, July 1, 2003. (Photo: L. M. Chan)
We especially relished familiarity with individuals. Male 3 courted females but never
mated, whereas male 26, at about four feet long and three pounds our largest black-
tail, had an enormous range and successfully courted several females. Superfemale 21,
as I later called my all-time favorite snake, was an excellent hunter and good mother,
plus she stayed out of trouble; over the course of twelve years she showed more meal
bulges than any of the others, guarded four litters through their vulnerable first days,
and never betrayed her camouflage by rattling. Woodrats and rock squirrels are staple
prey for this species, but one morning our star gal struck a desert cottontail, followed
the wounded rabbit's chemical trail for more than two hours, and consumed it ninety
yards from the ambush site.
Watching the blacktails not only yielded generalizations about their biology but
sometimes also left us grinning and shaking our heads in disbelief. One morning male
41 crawled over the cobbles and dry leaves of a shady ravine, stopped abruptly, and for
thirteen minutes meticulously tongue-flicked a cliff chipmunk's runway. Then he coiled,
his head pointed at the little squirrel's path. Because hunting-site selection had rarely
been seen, we lingered, observing with binoculars from a few yards away. A dry fern
was centered eight inches into the rattler's strike zone, and after two minutes he ex-
tended the crooked neck posture with which males fight over females, crushed the ob-
structing plant, and re-formed his ambush coil. I shot Dave a skeptical glance and was
reassured by his whispered, “He bent down that fern!” Later, after I published those
ing a prairie rattlesnake tamp down grass around rodent burrows before setting up its
ambush.
