|
Southern grasshopper mouse
Body size averages between 9-13 cm for the head and body, and 3-6 cm
for the tail. Covered with fine, dense fur. The upper body is a
grayish or pinkish-cinnamon color. The basal two-thirds of the tail
are colored like the upper body. The underside and terminal tip are
both white. The tail of O. torridus is longer than half the length
of its head and body.
Reproduction
Grasshopper mice are capable of breeding year-round, but most
reproductive activity occurs during the late spring and the summer.
Gestation lasts 26-35 days. Females born as early as April may
produce two or three litters before year's end. Females born in late
summer may have as many as six litters during the following breeding
season. Litter size ranges from one to six young. Young weigh
approximately 2.6 grams. They open their eyes at two weeks of age,
immediately begin nursing from their mother, and are weaned at three
weeks of age. Females seldom breed after two years of sexual
maturity.
Behavior
Grasshopper mice are extremely aggressive predators. They are
largely nocturnal, good climbers, and active year round. They hunt
their prey like most sophisticated predators. After stalking their
potential kill, they seize the animal with a rush, killing with a
bite to the head. While overpowering their prey, O torridus closes
its eyes and lays its ears back. Grasshopper mice are solitary
animals, guarding their large territory fiercely against all
intruders. They may, however, live in male-female pairs year round,
although this seems to shorten the life span, as one of the two
partners inevitably kills the other. Grasshopper mice often commit
acts of cannibalism, killing and eating other members of their
species if they are threatened or in need of food. Perhaps the most
unusual thing about the grasshopper mouse is its trademark "howl".
Onychomys can produce a loud, piercing, pure tone, which lasts
between 0.7 and 1.2 seconds, and is audible to the human ear up
to100 meters away. Standing on their hind legs with their noses
pointed upwards, they give this call when faced with an adversary,
including other grasshopper mice, or prior to making a kill. This
shrill warning, often repeated, is compared to a miniature wolf
call, due to its smoothness and prolongation, and to the animal's
wolf-like posture.
Food Habits
10-25% of the diet of O. torridus consists of seeds, plants, and
vegetables. The remainder includes mainly scorpions, but also
grasshoppers, beetles, and small vertebrates, including other
rodents, such as Peromyscus, Perognathus, and Microtus.
In captivity they should be offered a complete diet of rodent lab blocks, and rat or mouse
mix, with bits of fruit or veggies regularly. Cheerios or wheat
bread are great treats, in small quantities. Do NOT feed chocolate,
fried foods, salted foods, candy or junk food! They may enjoy
crickets and mealworms if they are captive bred, never feed wild
insects as they may carry parasites. Vitamins, like Nutri-Cal are a good addition to their diet, and added calcium
during nursing and growth due to demands on their systems at those
times, but take care not to overdo it. Water bottles should be used
to proved constant, clean water. Ceramic or stoneware food dishes
work well for keeping seeds or fresh foods off the floor, and a wire
mesh hopper that allows them to eat the lab blocks through without
extra waste.
|
