Dipodomys compactus is believed to be the most primative of the extant kangaroo rats due to its tooth morphology. Also, many Dipodomys go their entire life without drinking free-standing water. They have developed a way of concentrating their urine more effectively than any other North American mammal. All of their water is metabolic or comes from foods that are ingested.
Research on communication in D. comapctus is not extant. However, it is likely that this species is like other members of the genus. Kangaroo rats are not highly vocal, although they do make sounds. Most communication is through scent cues and foot drumming. Tactile communication occurs between mothers and their young, between mates, and between combatants in territorial aggression. Some visual signals, such as body posture, are probably also used in communication with conspecifics.
Communication Channels: visual ; tactile ; acoustic ; chemical
Other Communication Modes: scent marks ; vibrations
Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical
The range of D. compactus is rather small, but the population is healthy and shows no signs of decline. This species is not protected under IUCN, ESA, or CITES as of this time.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
Dipodomys compactus has been known to pick seeds from newly planted fields.
Negative Impacts: crop pest
There is no evidence that this species produces a postive impact on human economies, although, as food for handsome predators, it may provide some indirect benefit to human populations.
Gulf Coast kangaroo rats are food for a variety of animals. They also implact the plant community through herbivory and dispersal of seeds.
Ecosystem Impact: disperses seeds; soil aeration
Preferred foods consist of grasses, seeds, annual plants, and shrubs. Insects, fruits, buds, leaves, and stems also make up a part of their diet. Dipodomys have been known to amass up to 50 quarts of seeds and grains in their underground storage chambers.
Like other members of the genus, D. compactus does not need to drink water. This is clearly an adaptation to the very dry habitats it occupies. These animals make water metabolically, and obtain some from the moister foods they eat. They conserve water by making really concentrated urine.
Animal Foods: insects
Plant Foods: leaves; roots and tubers; wood, bark, or stems; seeds, grains, and nuts; fruit
Foraging Behavior: stores or caches food
Primary Diet: herbivore (Granivore )
Dipodomys compactus has a limited distribution in the southernmost region of Texas and on the islands in the Gulf of Mexico just off the Texas coast. The islands they inhabit run from the Padre Island region in the North, to the barrier islands of Tamaulipas Mexico in the South.
Biogeographic Regions: nearctic (Native )
Other Geographic Terms: island endemic
The habitat of D. compactus remains relatively homogeneous throughout their range. Sandy soils that are disturbed or loose are favored. Along with sandy soils, they have a preference for open, sparsely vegetated dunes. Almost all of these animals are captured on the leeward or sheltered side of the landform they inhabited. It is also noteworthy that very few individuals have been captured in undisturbed brush covered areas.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: desert or dune
Other Habitat Features: agricultural
Dipodomys have lived up to 9.8 years in captivity. However, the average life span in the wild is around 2 years. It is likely that D. compactus compares to other members of the genus.
Range lifespan
Status: captivity: 9.8 (high) years.
Average lifespan
Status: wild: 2 years.
Dipodomys compactus is of medium size, weighing between 44 and 60 g. Males of the species are larger than females, weighing an average og 53 g compared to the average of 45 g for females. However, males are smaller in cranial comparisons. The total length of these animals is between 203 and 266 mm, with males averaging 228.1 mm and females averaging 227.6 mm. The tail length is between 104 and 135 mm, with males and females both averaging just over 199 mm.
Pelage coloration varies slightly between individuals. The color can range from a gray phase to a reddish orange tint. The varying color is found underneath the black guard hairs on the back, and more noticeably on the sides. The hairs are short and fairly coarse. All color phases have white cheek patches.
Range mass: 44 to 60 g.
Range length: 203 to 266 mm.
Sexual Dimorphism: sexes alike; male larger
Other Physical Features: endothermic ; bilateral symmetry
As with any North American rodent, common ground dwelling predators include coyotes, foxes, raccoons, and various other carnivores. Rattlesnakes, owls, and hawks also prey on this species. Footdrumming may be a warning signal used when encountering snakes.
Known Predators:
Anti-predator Adaptations: aposematic
The only time D. compactus is not solitary is during the breeding season. Other than that, very little is known of the breeding and mating behaviors. Sexual dimorphism in this species suggests polygyny.
Very little is known of the reproductive behavior of D. compactus. Two individual cases have been observed and recorded. A pregnant female was captured on the 6th of July while carrying 2 embryos. A separate female was taken on the 23rd of August showing signs of two placental scars.
Reproduction in other species of this genus has been fairly well documented. In the genus Dipodomys, breeding can occur throughout the year, but tends to be fine tuned to food availability. Most species are polyestrous. The estrous cycle in Dipodomys ordii is short, lasting only 5-6 days. Cycle lengths for Dipodomys merriami and Dipodomys microps were recorded as 12 and 13 days, respectively. It is not know where in this range of variation D. compactus falls. Most species in the genus can produce two or three litters in a year.
Gestation lengths of between 29 and 26 days have been recorded for members of the genus. The longest gestations were recorded after a postpartum estrus. Litter sizes of 1 to 6 young have been recorded, which is consistent with the average of 2 young per litter observed in D. compactus.
The young are altricial, with birth weights of 3 to 6 g. In Dipodomys hermanni, hairs are reported to be visible at approximately 14 days of age. Weaning takes place at anywhere from 21 to 29 days, although the young may remain in their natal nest for as many as five weeks. Ability to dig small pits is seen at 40 days in D. hermanni, and by two months of age, members of this species can dig tunnels as long as 20 cm. Animals within the genus Dipodomys can become reproductively mature at 2 months of age under good conditions. Adult weight in D. hermanni was not attained until 10 to 16 weeks of age, and adult pelage not until 17 to 20 weeks.
Although it is not known with certainty how D. compactus compare to other members of the genus in reproductive parameters, it is likely that it is similar.
Breeding interval: Most species of Dipodomy breed two or three times per year.
Breeding season: Breeding in Dipodomys may occur throughout the year, but seems to peak in the summer.
Average number of offspring: 2.
Range age at sexual or reproductive maturity (female): 60 to 84 days.
Range age at sexual or reproductive maturity (male): 60 to 84 days.
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
No research has been done specifically for D. compactus, but in general, Dipodomys young are raised by the mother until they are ready to set out on their own. Young are born without hair, and don't open their eyes for the first two weeks of life. Dipodomys mothers have been known to move their litters around by carrying them to avoid danger or flooding. Male parental behavior has not been reported.
Parental Investment: no parental involvement; altricial ; pre-fertilization (Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Protecting: Female)
The Gulf Coast kangaroo rat (Dipodomys compactus) is a species of rodent in the family Heteromyidae found in Mexico and the state of Texas in the United States.[3] Its appearance and ecology are very similar to those of its putative sister species, Ord's kangaroo rat.[4]
Adult Gulf Coast kangaroo rats are about 220 mm (8.7 in) long including a tail of about 120 mm (4.7 in). There are two distinct color forms, an ashy gray and a reddish- or yellowish-buff. In both cases the purest color is on the sides and flanks with hairs in the dorsal region having dark tips giving a blackish sheen. The cheeks are white and the ears and upper and lower tail stripes are brown. This species is generally paler in color than other kangaroo rats and can be distinguished from the Ord's kangaroo rat by its shorter, uncrested tail and its shorter, coarser fur.[5]
The Gulf Coast kangaroo rat is found in southeastern Texas, southwards from Bexar and Gonzales counties, and in Zapata County, in Mustang Island and Padre Island, just off the coast of Texas, and in the barrier islands off the state of Tamaulipas in Mexico.[1][5]
The Gulf Coast kangaroo rat is mainly nocturnal and feeds on seeds which it collects in its cheek pouches and carries back to its burrow.[1] It lives in sparsely-vegetated locations with sandy soils, often among dunes and normally on the down-wind slope of a dune. Plants found growing in the vicinity include sea oats (Uniola paniculata), bluestem grass (Andropogon), saltgrass (Distichlis), fringe-rushes (Fimbristylis), sunflowers (Helianthus) and croton (Croton). In sparse mesquite (Prosopis) savannah in Texas it is associated with wiregrasses (Aristida), hairy grama (Bouteloua hirsuta) and hooded windmill grass (Chloris cucullata), as well as prickly pear (Opuntia).[5]
The population trend of the Gulf Coast kangaroo rat appears to be steady and no particular threats have been identified. In suitable habitat it is quite common and the IUCN has listed it as being of "least concern".[1]
The Gulf Coast kangaroo rat (Dipodomys compactus) is a species of rodent in the family Heteromyidae found in Mexico and the state of Texas in the United States. Its appearance and ecology are very similar to those of its putative sister species, Ord's kangaroo rat.
