Euoticus elegantuluswestern needle-clawed galago

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Geographic Range

Eouticus elegantulus occupies the upper levels of the African rainforest canopy throughout the countries of Southern Cameroon, south of the Sanaga River, Rio Muni (Mainland Equatorial Guinea), Gabon, Congo and South Nigeria. (Macdonald, 1987)

Habitat

Needle-clawed bushbabies live in primary and secondary forests. They are completely arboreal and nocturnal, occupying the closed canopy of Africa’s tropical rainforest up to about 50 m in height. (Sussman, 1979)

Physical Description

Euoticus elegantulus receives its common name from its distinctive nails. These primates have needle-like nails on all digits except the second toe, which has the usual toilet claw. The nails have a central keel that comes to a point and the tips of the fingers are well padded to help grip barks while these animals forage for gums.

Needle-clawed bush babies are monomorphic, ranging from 495 to 555 mm in length from head to tip of tail. Without the tail, they range from 215 to 235 mm. They weigh between 270 and 360 g.

The fur is very soft, dense, and cinnamon tinted with a darker median dorsal stripe. The tail is long and cylindrical. These animal have short muzzles, huge eyes, and large mobile ears to help keep a lookout for predators. They can also rotate their heads 180 degrees.

Galagos have four incisors and two canines which form a “tooth comb”. This structure helps them to groom their fur. To help clean the tooth comb they have a second, fleshy comb, armed in front with hard pointy horns, and located under the tongue.

No geographic or seasonal variation has been reported. E. elangantulus is distinguished from other bush babies by having a different fur color, different dentition, and a thicker tail. (Hill, 1953; Nowak, 1999; Singapore Zoological Gardens Docents, 2001)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    270 to 360 g
    9.52 to 12.69 oz
  • Range length
    495 to 555 mm
    19.49 to 21.85 in
  • Average basal metabolic rate
    1.205 W
    AnAge

Development

In captivity individuals can live up to fifteen years.

(Macdonald , 1987)

Reproduction

The mating system of these small, nocturnal primates has not been reported. Male ranges overlap with those of females, suggesting some level of polygyny in the mating system.

Euoticus elegantulus has no fixed breeding season. Studies have shown that they can have two breeding seasons per year: One in mid-summer and one in mid-winter, depending on food abundance. Females bear a single offspring at a time. Gestation period is about 4 months.

Young of this species can catch insects by 4 to 8 weeks of age. They are weaned by 6 to 11 weeks. By the age of 4 months, a young galago is independent of the mother, but it continues to grow and develop for a year.

When a baby is born, the mother hides out for 3 days away from the male, which might kill the newborn. Infants are born fully furred with their eyes open. Although they have poor coordination, they have the ability to cling to their mother's fur right after birth.

When a mother is foraging she leaves her infant in a nearby hidden nest, or carries the baby with her in her mouth, occasionally leaving it clinging on a nearby branch while she collects food.

Age of sexual maturity is not known for this species. (Flannery, 2001; Hill, 1953; Singapore Zoological Gardens Docents, 2001)

  • Breeding interval
    A female can breed twice per year, depending on food availability.
  • Breeding season
    There is no fixed breeding season, but peaks may occur in mid-summer and mid-winter.
  • Average number of offspring
    1
  • Average number of offspring
    1
    AnAge
  • Average gestation period
    4 months
  • Average gestation period
    122 days
    AnAge
  • Range weaning age
    6 to 11 weeks
  • Average time to independence
    4 months

The mother nurses her young for about 6 to 11 weeks. During that time, she cares for the young by carrying it with her on foraging trips, or keeping it safe in a nest.

No male parental care has been reported. (Singapore Zoological Gardens Docents, 2001)

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

Lifespan/Longevity

These animals are thought to live 3 to 4 years in the wild, and 10 to 15 years in captivity. (Flannery, 2001)

  • Range lifespan
    Status: wild
    3 to 4 years
  • Range lifespan
    Status: captivity
    10 to 15 years

Behavior

Euoticus elegantulus is considered a nocturnal and solitary forager, even though it isn’t purely nocturnal or purely solitary in foraging. These animals do have activity in the day as well. After their nightly foraging, at dawn females form matriarchal groupings and have close contact and mutual licking. Females sleep with their young. They may also sleep in groups averaging 2 to 8 galagos, but which can be as large as 20 animals. These sleeping associations are thought to reinforce social bonds. Some mated pairs may sleep together and at other times the male may keep in close contact with the females in his territory outside of the nest.

Females forage in small groups, but males forage alone. Experiments have shown that females chase other adult females introduced into their home ranges. Galagos are territorial and warn off rival groups with warning calls. They mark their territory with scents from various scent glands.

The dominant male in an area is typically the heaviest. His territory overlaps with that of most of the females. He will tolerate light-weight males in his territory and moderate-weight males on periphery of his territory. Light–weight males are nomadic until they gain sufficient weight to hold a territory of their own.

Southern needle-clawed galagos are quadrupedal runners and leapers. They leap from tree to tree and can cover a 12 m space in a single upward jump. When gliding, these animals use a parachuting method where they spread their arms and legs out to achieve maximum surface area to slow their descent.

In this species males disperse and females are philopatric. (Flannery, 2001; Singapore Zoological Gardens Docents, 2001)

Home Range

Home range size for this species is not reported.

Communication and Perception

Bush babies were named after the cries they emit to identify their territory, which sound like a crying baby. They are constantly prepared for instant flight. They have a series of alarm calls to alert conspecifics to threats of danger. Their series of calls include territorial calls, which sound like a "quee"; alarm calls, which sound like "tee-ya"; infant calls, which sound like "tsic"; maternal calls, which also sound like the infant "tsic" call, but are more powerful; contact-rejection calls, which sound like "ki-ki-ki", and are staccato; aggressive calls, which are described as a "hoarse growl"; and distress calls, which sound like "weet".

Bush babies also have a large glandular area that is used for olfactory communication (scents are secreted from a brachial gland). They will also deposit urine for territorial markings and have social grooming to strengthen the mother/infant bond. (Hill, 1953; Nowak, 1999; Singapore Zoological Gardens Docents, 2001)

Food Habits

Euoticus elegantulus is a nocturnal feeder, and is primarily gummivorous. The needle-clawed nails of this species are specially adapted for this diet. They also feed on insects and fruits. Seventy five percent of the diet of this species consists of gums, 20% insects, and 5% fruits (along with some buds). The types of gums they eat upon are, Entada gigas, Albizia gummifera, and Pentacletra eetveldeana.

When foraging for gums, needle-clawed galagos use a regular pathway of trees, stopping at each one every night. These animals can stop at 500 to 1000 gum feeding locations in a single night.

The type of insects and other invertebrates that bushbabies eat belong to the orders Coleoptera (beetles), Lepidoptera (both caterpillars and moths), Orthoptera (grasshoppers), Hymenpoptera (ants), Isoptera (termites), Myriapoda (centipedes and millipedes), Arachnida (spiders), and Gastropoda (slugs). During the dry season, this species strictly survives off of gums. (Nowak, 1999; Sussman, 1979)

  • Animal Foods
  • insects
  • terrestrial non-insect arthropods
  • mollusks
  • Plant Foods
  • fruit
  • flowers
  • sap or other plant fluids

Predation

As predators, they keep the population of their prey in check. They are also eaten by larger creatures, mainly night birds of prey such as owls. (Singapore Zoological Gardens Docents, 2001)

Ecosystem Roles

As nectar feeders, these tiny creatures pollinate some plants. Galagos may also disperse the seeds of the fruits that they eat. As predators, they keep the population of their prey in check. E. elegantulus shares its habitat with another species of bush baby, Galago demidovii. They both exploit the canopy but there isn’t any real competition because they occupy different levels of the canopy and prey on different sizes of prey. (Flannery, 2001; Sussman, 1979)

  • Ecosystem Impact
  • disperses seeds
  • pollinates

Economic Importance for Humans: Positive

These animals are used in behavioral research, and are enjoyed by visitors to zoos.

  • Positive Impacts
  • research and education

Economic Importance for Humans: Negative

In 1940, it was discovered that galagos are a reservoir for the virus which causes yellow fever. Although the galagos don't become ill from this disease, mosquitoes can transmit the disease from the galagos to humans. (Flannery, 2001)

  • Negative Impacts
  • injures humans
    • carries human disease

Conservation Status

The biggest threat to the species E. elegantulus is habitat destruction. There is a lot of timbering and clearing of land for plantations and illegal hunting. To prevent forest primates from extinction, proper forest reserves will have to be put up and that demand sufficient funds. (Bermont and Lindberg, 1975)

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Lili Santilli (author), Humboldt State University, Brian Arbogast (editor), Humboldt State University.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

acoustic

uses sound to communicate

arboreal

Referring to an animal that lives in trees; tree-climbing.

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

dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates

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.

fertilization

union of egg and spermatozoan

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.

nocturnal

active during the night

omnivore

an animal that mainly eats all kinds of things, including plants and animals

polygynous

having more than one female as a mate at one time

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

saltatorial

specialized for leaping or bounding locomotion; jumps or hops.

scent marks

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

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.

solitary

lives alone

tactile

uses touch to communicate

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

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

Bermont, G., D. Lindberg. 1975. Primate Utilization and Coservation. New York: John and Wiliey Sons.

Flannery, S. 2001. "Southern Needle-clawed Galago (Euoticus elegantulus)" (On-line). Accessed (Date Unknown) at http://members.tripod.com/uakari/euoticus_elegantulus.html.

Hill, W. 1953. Primates: Comparitive anatomy and Taxonomy. Great Brittain: Edinburgh at the University Press.

Macdonald, D. 1987. The Ecyclopedia of Mammals. New York: Facts on file Publications.

Napier, J., P. Napier. 1985. The Natural History of the Primates. Cambridge Massachusetts: The MIT Press.

Nowak, R. 1999. Walker's Mammals of the World, Sixth Edition. Baltimore and London: The Johns Hopkins University Press.

Parker, S. P., 1990. Grizmek's ecyclopedia of mammals. West Germany: McGraw-hill Inc..

Singapore Zoological Gardens Docents, 2001. "GALAGOS or BUSHBABIES" (On-line). Accessed (Date Unknown) at http://www.szgdocent.org/pp/p-galago.htm.

Sussman, R. 1979. Primate Ecology: problem-Oriented Field Studies. New York: John Wiley and Sons.