Blanford’s Jerboa
Jaculus blanfordi occur in the southern and eastern desert plains of Iran, southern and western Afghanistan, and western Pakistan. They inhabit arid regions where extensive sand dunes are interspersed with gravel plains. These jerboas inhabit very arid rocky basins and areas of extensive rolling or flat sand dunes interspersed with gravel plains. They have also been reported from the shores of the Persian Gulf near Bushehr.
Blanford’s jerboa
Like all jerboas, Jaculus blanfordi are saltatorial animals that have specialized adapatations for their desert environments. All jerboas have elongated hind-limbs that are about four times as long as their forelimbs. The short forelimbs are positioned close to the head and used for gathering food and burrowing. Locomotion is performed using the hind-feet and the posterior end of their long tails. A unique adaptation of members of this genus is the fusion of the metatarsal bones into one “cannon bone” as well as the loss of the first and fifth toes on each hind foot. Undersides of the three remaining long and laterally compressed toes are covered with thick, stiff hairs. The combination of these features improves traction and provides powerful leverage, so it’s not surprising that members of this genus can jump to heights of nearly 2.25 m when escaping predators.
The pelage is thick, comprised of thin and soft hairs that are dorsally cream-colored but blending with white ventral hairs along the sides of the body. The eye-lashes and long sensory hairs are gray or black, and the whiskers are white. The thick and compressed toe hairs are white near the skin and dark brown on the outer edges. The tail tuft is divided black anteriorly and white posteriorly. They have large, round eyes that are set close to the ears, ovally elongated ears that are relatively small compared to other dipodids, and a fold of skin which can be pulled over the nose while burrowing.
Reproduction
Very little is known about the reproductive cycle of this species. Based on data from other members of the genus and from a few available collected specimens of Jaculus blanfordi, the gestation period is believed to be approximately forty days long. One to three litters are born each year and litters generally consist of three to four altricial young.
Behavior
Jaculus blanfordi are non-colonial, nocturnal rodents that spend their days sleeping and nights foraging. They build intricate burrows by beating and shaping the sand with their blunt heads and muscular noses, forming tunnels between 1.5-2.5 meters long. The burrows are characterized by one entrance and several exits. If a mound of soil is visible from above-ground, it is an indication of an emergency exit that the individual sometimes forms by lightly packing a hole and leaving it closed until an emergency arises. There are no food storages or excrements kept inside the burrows, but camel fur or other soft materials may be used to line the dens during the winter months. During the summer months, the openings are sealed with approximately 50cm of soil, an act that bedouins believe is to prevent snakes or warm air from penetrating into the burrow.
At night Jaculus blanfordi forage independently, sometimes over distances of several miles. Individual burrow systems are in close proximity to each other and, on numerous instances, individuals have been found sleeping in the same burrow during the day. Further studies are needed to determine the social systems of this species. Other species of this genus have been reported to hibernate in extreme temperatures. Although this behavior has not been studied in this species, Jaculus blanfordi in Iran have been observed to be actively foraging above ground late in December with temperatures below freezing. Daily cycles of complete torpidity in colder winter months have also been observed in captive individuals.
Food Habits
The diet consists mainly of leaves and sprouting vegetation in wet seasons and of succulent roots, seeds and grains when rainfall is low or in the summer. 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.
