Dasyprocta ruatanicaRuatan Island agouti

Geographic Range

Dasyprocta ruatanica is endemic to Roatán Island, which is approximately 48 kilometers off the coast of Honduras. A population occurs on Fantasy Island, which is about 30 meters off the middle south shore of Roatán Island. Roatán Island is a fault block, so it is unlikely that this species populated the island via land bridge. The original human inhabitants of the island, Payans, used agoutis as a food source, so this species was probably either there before the natives or brought with them. (Cox, et al., 2005; Jacobson, 1992; Lee, et al., 2000)

Habitat

Dasyprocta ruatanica is found in brushy, tropical scrub forests. Because of human development, most of the scrub forest that still exists on Roatán Island is on mountains. The highest point on Roatán Island is about 274 meters (900 feet) above sea level. On Fantasy Island, D. ruatanica is common on a tree-covered hill. Among the tree species present are Casuarina equisetifolia, Cocos nucifera, Pentaclethra, Swietenia, and Thrinax. Dasyprocta ruatanica utilizes patches of bamboo for sleeping. On Fantasy Island, D. ruatanica can also be found using the space under hotel buildings. (Lee, et al., 2006)

  • Range elevation
    0 to 274 m
    0.00 to 898.95 ft

Physical Description

Roatán Island agoutis, as well as other agoutis, look like large, long-legged guinea pigs. The head and body of an adult can be from 32 to 64 cm (12.6 to 25.2 in) long and weight between 0.6 and 4 kg (1.3 to 8.8 lb). They are smaller than closely related Central American agoutis (Dasyprocta punctata). The ears are naked and the tail is very short. Agoutis have 5 toes on their front feet and 3 on the hind feet. They have a digitigrade foot posture. The fur is orange-brown and hairs are annulated to the root. The ventral surface is like the back, but slightly more olive-colored. There is a white spot on the chin and a yellow patch in the middle of the belly. The body color darkens along the limbs to a dark brown color on the feet. ("Roatán Island agouti", 2005; Lee, et al., 2000; Lee, et al., 2006; Thomas, 1901)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    0.6 to 4 kg
    1.32 to 8.81 lb
  • Range length
    32 to 64 cm
    12.60 to 25.20 in

Reproduction

Little is known about the mating in Roatán Island agoutis. Central American agoutis (Dasyprocta punctata) form monogamous pair bonds and can breed year round. (Smythe, 1978)

Not much is known about reproduction in Roatán Island agoutis specifically. Some information may be inferred from their close relatives, Central American agoutis. Central American agoutis reach reproductive age at about 6 months old, but this can vary based on food availability and body size. Gestation is about 3.5 months long at which time 1 to 2 young are born. (Smythe, 1978)

  • Breeding interval
    Roatan Island agoutis can breed year round.
  • Range number of offspring
    1 to 2

Little is known about the extent of parental investment in Roatán Island agoutis. Juveniles of about two-thirds of the mother’s size have been observed participating in leading/following behaviors with the mother. At this size, mothers tend to back away when offspring try to nurse. In Cental American agoutis and other agouti species, females usually raise one or two precocial young. They can be observed grooming and bringing food to their young. For about the first two weeks the offspring stay in a small burrow while the mother goes foraging. However, Roatán Island agoutis have not been observed digging or using burrows. ("Roatán Island agouti", 2005; Lee, et al., 2000; Lee, et al., 2006; Smythe, 1978)

  • Parental Investment
  • precocial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

The only lifespan information available for Dasyprocta ruatanica is that individuals have reached the age of 13.7 years in captivity. (Weigl and Jones, 2005)

  • Range lifespan
    Status: captivity
    13.7 (high) years

Behavior

Roatán Island agoutis are not known to be territorial, though their close relative, Central American agoutis, have been known to scent mark trails, feeding, and sleeping spots. Agoutis are mostly diurnal. In an observation of the Fantasty Island population of Roatán Island agoutis, individuals were observed to spend an average of 23.1% of their time sitting and 22.0% feeding. Behaviors such as walking, sniffing, and digging were classified as “looking for food” and such behaviors occupied 29.2% of their time. In this case, digging is classified as looking for food because the animals seem to be burying seeds for storage. Marking took up 2.2% of the time. ("Roatán Island agouti", 2005; Lee, et al., 2000; Lee, et al., 2006; Smythe, 1978)

Home Range

There is no information on home range sizes in Roatán Island agoutis.

Communication and Perception

One social interactive behavior that has been observed in Roatán Island agoutis is muzzling. Another is fleeing with rump hairs erected, which is classified as a conflict behavior. Odor, thumping, and vocalizations are also important forms of communication in Central American agoutis, which can reasonably be inferred as important to D. ruatanica as well. (Lee, et al., 2000; Smythe, 1978)

Food Habits

Roatan Island agoutis are mostly frugivorous. Foods on Fantasy island include coconuts (Cocos nucifera), hibiscus flowers, almonds (Terminalia sp.) and Pentaclethre pods. They have also been observed feeding on rice, oranges, and corn kernels intended for domestic fowl. Like other agouti species, they dig holes for caching food. (Lee, et al., 2000; Lee, et al., 2006)

  • Plant Foods
  • seeds, grains, and nuts
  • fruit
  • flowers

Predation

On Fantasy Island there are no native carnivores. On Roatán Island humans are known to hunt agoutis for food. Unlike Central American agoutis, Roatán Island agoutis have not been observed digging burrows. Smythe (1983) suggested that in Central American agoutis, holes were dug as a method of predator avoidance. Lack of holes suggests that there are no natural predators for Roatán Island agoutis. However, these agoutis do raise their rump hairs when fleeing a threat, which may be a defense against being bitten by predators or conspecifics. (Lee, et al., 2000)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Agoutis in general seem to be important in the dispersal of plant seeds through the habit of scatterhoarding, which is the practice of caching food in scattered ground surface caches. (Smythe, 1978)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

Based on studies of Dasyprocta punctata and Dasyprocta mexicana, it has been suggested that D. ruatanica and other agoutis could be bred in captivity as a food source for humans. It has also been suggested that agoutis may be an ecotourist attraction. ("Roatán Island agouti", 2005; Jori, 2001)

Economic Importance for Humans: Negative

Other than using some of the foods put out for domestic fowl, there are no known negative impacts on humans. (Lee, et al., 2000)

Conservation Status

Roatán Island agoutis are classified as Endangered by IUCN due to its small range, ongoing habitat loss, habitat degradation, and hunting. Roatán Island agoutis occur in two protected areas, but hunting still occurs on Roatán Island. (Schipper, et al., 2008)

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Laurinda Hill (author), University of Alaska Fairbanks, Link Olson (editor, instructor), University of Alaska Fairbanks.

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

food

A substance that provides both nutrients and energy to a living thing.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

frugivore

an animal that mainly eats fruit

herbivore

An animal that eats mainly plants or parts of plants.

island endemic

animals that live only on an island or set of islands.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

tactile

uses touch to communicate

terrestrial

Living on the ground.

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year

young precocial

young are relatively well-developed when born

References

2005. Roatán Island agouti. M Hutchins, W Conway, eds. Grzimek's Animal Life Encyclopedia. Accessed December 08, 2008 at http://www.answers.com/topic/roat-n-island-agouti.

Cox, R., D. Lumsden, K. Gough, R. Lloyd, J. Talnagi. 2005. Electron Spin Resonance and Geomorphic Evidence of Holocene Uplift Along the North America/Caribbean Plate Boundary. Geological Society of America Abstracts with Programs, Vol. 37, No. 2: 39. Accessed December 08, 2008 at http://gsa.confex.com/gsa/2005SE/finalprogram/abstract_82431.htm.

Jacobson, S. 1992. The Bay Islands: Nature and People. Maimi, FL: Colonial Press International.

Jori, F. 2001. La Production de rongeurs en milieu tropical. Bois et Forets des Tropique, 269: 31-41.

Lee, T., H. Hartline, B. Barnes. 2006. Dasyprocta ruatanica. Pp. 1-3 in R Gettinger, K Helgen, L Marinelli, P Owens, V Hayssen, eds. Mammalian Species, Vol. No. 800. online: American Society of Mammalogists. Accessed November 10, 2008 at http://www.bioone.org/archive/1545-1410/800/1/pdf/i1545-1410-800-1-1.pdf.

Lee, T., D. Rhodes, J. Lynons, D. Brannan. 2000. The Natural History of the Roatan Island Agouti (Dasyprocta ruatanica), a Study of Behavior, Diet and Description of the Habitat. The Texas Journal of Science, 52(2): 52(2).

Schipper, J., L. Emmons, N. Woodman, R. Timm, T. McCarthy. 2008. "The IUCN Redlist of Threatened Species" (On-line). Accessed November 10, 2008 at http://www.iucnredlist.org/details/6287.

Smythe, N. 1978. The Natural History of the Central American Agouti (Dasyprocta punctata). Smithsonian Contributions to Zoology, No. 257. Accessed December 08, 2008 at http://si-pddr.si.edu/dspace/bitstream/10088/5240/2/SCtZ-0257-Lo_res.pdf.

Thomas, O. 1901. New insular forms of Nasau and Dasyrpocta. Annals and Magazine of Natural History, Series, 7, 8: 271-273.

Weigl, R., M. Jones. 2005. Longevity of Mammals in Captivity; from the Living Collections of the World. Stuttgart: E. Schweizerbart'sche Verlagsbuchhandlung, Science Publishers.