By Marisha Jaimes
Geographic Range
Myoprocta acouchy, also known as the red acouchy, can be found in Guyana, Suriname, French Guiana, and Brazil, north of the Amazon and east of the Rio Branco. Isolated populations may be found in Colombia and the upper Rio Vaupes. (Emmons, 1990)
Biogeographic Regions:
neotropical
(native
).
Habitat
The habitat of M. acouchy is dense undergrowth in lowland forests. Red acouchis are usually found around fallen trees that are used as runways. Males prefer open forest while females prefer a closed habitat. At night the red acouchis rest in nests of leaves, usually inside a hollow log. Rarely they can be found using burrows made by other species. When using these burrows, M. acouchy will plug up any entrances not in use with leaves. (Dubost, 1988; Emmons, 1990)
These animals are found in the following types of habitat:
tropical
; terrestrial
.
Terrestrial Biomes:
forest
; rainforest
.
Other:
riparian
.
Physical Description
(2.2 to 8.8 lbs)
(15.2 to 18.43 in)
Red acouchis range in total length from 386 mm to 468 mm. With masses between 1.05 kg to 1.45 kg. Red acouchis are dark chestnut-red or orange on the sides and legs. Their mid-back and rump are black or a very dark shade of red. Areas around the mouth and eyes, as well as behind the ears, are almost naked. The whiskers are well developed and are black in color. They have long limbs, the forefeet have four toes and a vestigial thumb with a claw, and the hind feet have three large elongated toes. These toes have hoof-like claws. They have black soles of the bottom of their feet. The mid-back and rump are covered in glossy black or dark red hairs. Some may have an olivaceous appearance. Rump hairs are not banded, which distinguishes them from their close relative Myoprocta pratti, commonly known as green acouchis. Rump hairs are long and straight, hanging over the tail region. Red acouchis have a slender, short tail, which is white underneath as well as at the tip. The tail is often held up, exposing the white underside. (Emmons, 1990)
Some key physical features:
endothermic
; homoiothermic; bilateral symmetry
.
Sexual dimorphism:
sexes alike.
Reproduction
Red acouchis can breed multiple times during a year.
In captivity breeding occurs year round. They tend to have a birth peak in the summer months.
Red acouchi courtship may be highly ritualized, simular to their close relatives in the genera Dasyprocta and Agouti. What is known about the courtship of red acouchis is that males will mark the ground with anal glands when pursuing females. This is done by dragging the hind quaters across the ground. They will also follow females around with the front legs trembling and emitting a high pitched sound. When aroused, the hair on the back and flanks will stand up and go back down suddenly. Ocassionally males will also splash females with urine. (Eisenberg and Redford, 1999; Eisenberg, 1989)
The actual breeding season of the red acouchis in the wild is not well studied. In captivity the species has been observed breeding year-round. When this occurs, there usually is a peak in births during the summer months. Males are fertile year round, while females go into anestrus during the summer. The estrous cycle for red acouchis averages about 42 days. The gestation period averages 99 days. The number of offspring produced in a single litter is from 1 to 3 young with a average of 2. The young will nurse for 2 to 3 months before becoming fully weaned. Young of both sexes will become sexually mature at approximately 304 days. Post-partum estrus can occur but females will usually mate after the young are fully weaned. (Nowak, 1999)
Key reproductive features:
iteroparous
; year-round breeding
; gonochoric/gonochoristic/dioecious (sexes separate); sexual
; viviparous
; post-partum estrous.
Young red acouchis are precocial. Even so, they will remain sheltered inside a burrow until they are several weeks old. The mother returns to the nest burrow to nurse the young. Male red acouchis do not help with raising young. (Eisenberg, 1989)
Parental investment:
precocial
; pre-fertilization (provisioning, protecting: female); pre-hatching/birth (provisioning: female, protecting: female); pre-weaning/fledging (provisioning: female).
Lifespan/Longevity
There is little documentation of the longevity of M.acouchy, the longest living captive animal lived over 10 years. (Grzimek, 1990)
Behavior
There is conflicting information on whether these animals are solitary or social. Emmons states that these animals are solitary, whereas Nowak mentions that these animals will live in social groups usually consisting of one adult male, one adult female, and juveniles. Nowak also states that even though the animals live in groups as big as seven individuals, they seem to use separate home ranges. They are diurnal and move about on the forest floor in a characteristic crouched run. (Emmons, 1990; Nowak, 1999)
Home Range
During the wet season the home range of red acouchis ranges between 9,600 sq. meters to 12,000 sq. meters. Home range size is smaller during the dry season, from 6,500 sq. meters to 7,300 sq. meters. (Dubost, 1988; Nowak, 1999)
Communication and Perception
When alarmed, red acouchis stomp their hind feet and emit a whistle. They also emit a series of high pitched sounds, including a screech like squawk. Red acouchis can be detected by listening for the gnawing sounds they make while eating seeds and nuts. (Emmons, 1990)
Other communication keywords:
vibrations
.
Food Habits
Red acouchis are herbivorous, eating mainly fruits, nuts, seeds, and the cotyledons of seedlings. They are known for burying seeds in the forest floor for use during the dry season, when food is scarce. (Emmons, 1990)
Plant Foods:
wood, bark, or stems; seeds, grains, and nuts; fruit.
Foraging Behaviors:
stores or caches food
.
Predation
- large snakes (Serpentes)
- jaguars (Panthera onca)
- ocelots (Leopardus pardalis)
Red acouchis are prey to many medium-sized tropical, lowland predators, such as snakes and cats. When threatened by a predator, they emit an alarm call. When they flee, it is usually only for a few yards, where they will then hide motionless in a thicket or behind a fallen log. They have been known to circle silently and approach a motionless observer from behind after originally fleeing in alarm. (Emmons, 1990; Macdonald, 1999)
Anti-predator adaptations::
cryptic
.
Ecosystem Roles
The red acouchi behavior of burying seeds helps in the dispersal of seeds of many tree species. Red acouchis are also common prey for many tropical lowland predators. (Macdonald, 1999)
Key ways these animals impact their ecosystem:
disperses seeds.
Economic Importance for Humans: Negative
There are no known adverse effects of M. acouchy on humans.
Economic Importance for Humans: Positive
Red acouchis help with forest regeneration when they bury the seeds of plants species in different places for the use during the dry season. They are also hunted by locals as a valuable meat source. (Nowak, 1999)
Ways that people benefit from these animals:
food
.
Conservation Status
IUCN Red List: [link]:
Lower Risk - Least Concern.
US Federal List: [link]:
No special status.
CITES: [link]:
No special status.
State of Michigan List: [link]:
No special status.
Red acouchi populations seem stable, they are considered lower risk/least concern by the IUCN.
Other Comments
The scientific name for M. acouchy was formerly Myoprocta exilis. Some of the local common names of M. acouchy are cutiara, acoechi, and maboela. (Emmons, 1990; Woods and Kilpatrick, 2006)
Contributors
Tanya Dewey (editor), Animal Diversity Web, University of Michigan Museum of Zoology.
Marisha Jaimes (author), University of Wisconsin Stevens Point. Chris Yahnke (editor, instructor), University of Wisconsin Stevens Point.
