Although Talas tuco-tucos are fairly solitary animals, spatial organization within a population is socially important. They clearly recognize odors from urine, feces, and wood shavings from other individual members of the population. Scent recognition helps to uniformly distribute burrows within a specific area. In addition to being spatial cues, these sex distinctions are significant in mating behavior.
Talas tuco-tucos also communicate with vocalizations. Only males produce the “tuc” sound, which gives rise to the common name of the family (tuco-tuco). The song consists of multiple “tuc” sounds, lasts roughly ten to twenty seconds, and serves to establish spatial organization. This means of communication is also implicated in mating behavior.
Communication Channels: acoustic ; chemical
Other Communication Modes: scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
There are no known conservation efforts for Ctenomys talarum.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
The mounds and burrows of C. talarum bare and erode soils in some agricultural areas.
Negative Impacts: crop pest
There are no known positive effects of Ctenomys talarum on humans.
This species is an herbivore. Its grazing activities and burrowing impact the composition of plant communities where it lives.
Ctenomys talarum is parasitized by several families of the order Nematoda, as well as several lice species, such as Eulinognathus americanus, Gyropus parvus, and Phtheropoios forficulatus. Although prevalence of parasitism does not differ between sexes of C. talarum, the intensity does vary.
In populations near urban areas of the Buenos Aires Province, C. talarum is an intermediate host of the cestode parasite Taenia taeniaeformis. A prevalence of 64% in some populations indicates that C. talarum is an important host to the parasite, whose final host is domestic dogs, a common predator of C. talarum in urban areas.
Ecosystem Impact: creates habitat; soil aeration
Talas tuco-tucos are herbivorous, feeding on roots and grasses. Unlike most subterranean rodents, Talas tuco-tucos leave their burrows to forage for vegetation above ground. Captive C. talarum preferentially consume the grass species Bromus unioloides.
Plant Foods: leaves; roots and tubers
Primary Diet: herbivore (Folivore )
Ctenomys talarum is a South American rodent found only in eastern Argentina. They are also known as Talas tuco-tucos. Three subspecies are morphologically similar and are distinguished only by the specific region which each occupies: C. t. occidentalis along the eastern border of the province of La Pampa; C. t. recessus along the southern coast; and C. t. talarum along the eastern coast of the province of Buenos Aires.
Biogeographic Regions: neotropical (Native )
Talas tuco-tucos spend most of their lives in underground burrows, which can be found in pastures with flat terrain. Burrows have a branching structure, measure 6 to 8 cm in diameter, are shorter than 25 m in length, and are at least 30 cm in depth. Compared to neighboring sympatric species C. australis, C. talarum prefers firmer, more organic soils, which tend to host a denser composition of vegetation.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland
In wild populations, the overall mortality rate of C. talarum is 0.05 per week. The probability of survival during the winter (March to October) is 0.19, while the probability of survival during the summer (October to March) is 0.38. With a lifespan of 20 to 22 months, individuals rarely live through more than two reproductive seasons.
In captivity, Ctenomys talarum develops hyperglycemia and cataracts. As much as 40% of individuals in a colony show deteriorative eye change. Blood sugar levels may increase nearly 75%.
Status: wild: 20 to 22 months.
Status: wild: 3.0 years.
Ctenomys talarum has a cylindrical body, reduced neck, and short tail. Mean total length ranges from 212.0 to 254.0 mm, mean length of head and body is 167.5 mm, and the mean tail length is 66.7 mm. The mean skull length and mean nasal length are 37.4 mm and 11.9 mm, respectively. The average breadth of braincase for C. talarum is 14.6 mm. Males and females have mean masses of 186.0 g and 128.0 g, respectively, while the average mass for all recorded individuals is 133.0 g. Baculum is small and narrow, with a mean length and proximal and distal breadth of 6.4 mm, 1.32 mm, and 0.9 mm, respectively.
The short, fine hair of C. talarum is dark grey to black dorsally, blending to reddish-brown laterally and cream ventrally. Distinct white patches are found at the base of each ear, as well as in the inguinal and axillary areas. The tail is brown and dark grey. Hind feet have white, bristle-like hairs, and both front and hind feet have long, curved claws. Both eyes and ears are small. Cteonmys talarum molts during the summer and autumn seasons. Some intersexual differences exist in the five-phase molt; females molt earlier than males.
Ctenomys talarum is distinguished from closely related species in that it is, by measure of total length, smaller than C. azarae, C. australis, and C. mendocinus. Tail length of C. talarum is also noticeably smaller than that of C. australis and C. mendocinus. Compared to C. azarae, C. talarum has short and broad nasals. Ctenomys talarum is distinguished from C. minutus and C. torquatus by its smaller, flatter baculum.
Range mass: 0.090 to 0.190 kg.
Average mass: 0.133 kg.
Range length: 212.0 to 254.0 mm.
Average length: 233.4 mm.
Range basal metabolic rate: 1.08 to 2.00 cm3.O2/g/hr.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Talas tuco-tucos are preyed on by several species of carnivorous birds, including Athene cunicularia, Asio flammeus, and Tyto alba. Predators also include several carnivore species, such as Galictis cuja and Leopardus geoffroyi. Near urban areas, domestic cats and domestic dogs prey on Talas tuco-tucos. The primary predator-avoidance strategies include cryptic fur coloration and the ability to dig rapidly and efficiently close openings to their underground tunnels.
Anti-predator Adaptations: cryptic
Ctenomys talarum clearly recognizes interspecific chemical signals from cues in urine, feces, and soiled wood shavings. Each sex distinguishes the scents of same and other sexes. Furthermore, C. talarum identifies the reproductive status of individuals of the opposite sex and selects mates via such chemical cues.
Mating behaviors of C. talarum depend a great deal on vocalizations. Only males produce the “tuc” sound, which gives rise to the common name of the family (tuco-tuco). The song consists of multiple “tuc” sounds, lasts roughly ten to twenty seconds, and serves to establish the spacing of individual males within the area.
Paternity tests using DNA analysis and analyses of testes size have shown that C. talarum is polygynous. In these studies, a single male was found to have sired offspring litters with multiple females.
Usually, C. talarum is solitary, and only one individual inhabits each burrow. However, during the breeding season, males and females are often found together in the same burrow.
Mating System: polygynous
Male Talas tuco-tucos have extended reproductive availability, covering most of winter and into summer. Females are more restricted in their breeding availability. Talas tuco-tucos have two reproductive periods, interrupted by an inactive period of 6 to 8 months. All males are reproductive in July, and the majority of pregnancies occur in August. During the breeding season, the mean prevalence of pregnancy is 0.66.
Most births occur between October and December, and average litter size is between 4 and 5 offspring. The energetic costs of gestation and lactation are similar, although the gestation period is twice as long as that of lactation. When young are about 30 days old, females refuse to allow suckling. Females exhibit postpartum estrus, and it is possible that a female may be pregnant and lactating at the same time. At the point of sexual maturity, the average weights of females and males are 137.52 g and 176.62 g, respectively. Females tend to maintain a constant weight after reaching maturity.
In captivity, the age of first reproduction is eight months, and females come into estrus two times per year. Captive C. talarum has an average gestation period of 102 days and a mean litter size of 5 offspring, with a range of between 1 and 7 individuals.
Breeding interval: The reproductive cycle for C. talarum is bimodal, with two litters produced per year. An inactive period of 6 to 8 months separates these episodes.
Breeding season: Although males are reproductively capable for nearly eight months of the year, the breeding season for females is much more restricted. The majority of mating episodes occur in the months of July and August.
Range number of offspring: 4.000 to 5.000.
Average number of offspring: 4.55.
Average gestation period: 102 days.
Average weaning age: 30 days.
Average time to independence: 60 days.
Range age at sexual or reproductive maturity (female): 6 to 8 months.
Range age at sexual or reproductive maturity (male): 6 to 8 months.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; post-partum estrous
Average birth mass: 8 g.
Average gestation period: 102 days.
Average number of offspring: 4.
Apart from the mating episode, male and female Ctenomys talarum do not interact. Thus, females are responsible for all aspects of caring for offspring. Male C. talarum provide no prenatal or parental care.
Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
The Talas tuco-tuco is a large rodent ranging in size from 212 to 254 mm (8.35 to 10.00 in), more than twice the size of a house mouse. Its tail length varies from 56 to 75 mm (2.20 to 2.95 in) and it weighs approximately 118 g (4.2 oz). The species shows significant sexual dimorphism. The Talas tuco-tuco basically has a cylindrically-shaped body, but is larger around the head and shoulders. It has short fine hair, which is normally a mix of hazel, gray and red on the back, and white on the underparts. It also has a distinct white patch on either side of the head, along the lower edge of its ears. Its eyes and ears are small compared to its headband it has very long, curved claws on all four feet.
The Talas tuco-tuco is subterranean, living in burrows. Only one inhabits a particular burrow at a time; however, some build extensive burrowing systems connecting individual burrows with tunnels. They prefer areas with loamy soil, grass, perennials plants and woody shrubs. In some cases, they can be found in sandy soils as well. They are usually found along the coasts of the Buenos Aires, La Pampa and Santa Fe provinces.
Talas tuco-tucos are herbivorous, feeding on roots and grasses. Unlike most subterranean rodents, Talas tuco-tucos leave their burrows to forage for vegetation above ground.
Males can be sexually active throughout the year, but females have a much more restrictive breeding season, so that most pregnancies occur around August. An average litter consists of four offspring, with a slight about 1.63 females being born per male. The lactation period is estimated at about 45 days. In a study, one male was found to have copulated with all the females in the area.
Predators include the burrowing owl, short-eared owl, barn owl, and variable hawk. Lice that feed on the species include Eulinognathus americanus, Gyropus parvus, and Phtheropoios forficulatus.  Trichostrongylids can be found in the small intestine, and trichurids in the caecum of the Talas tuco-tuco.
The Talas tuco-tuco is solitary, aggressive and territorial. They use scent recognition to distinguish between individuals. Males engage in one on one confrontations with other males for prospective mates, using their sharp incisors as weapons. These can also be used as digging tools, but they prefer to use their claws when building their burrows. Although they are subterranean, they spend much of their time above the ground, foraging for food.