Rusa alfrediVisayan spotted deer

Geographic Range

Rusa alfredi is found only on the Visayan Islands, which are located in the central Philippines. This is one of the rarest, least known, and most narrowly disributed species of deer in the world. Formerly R. alfredi inhabited the larger Visayan Islands of Panay, Negros, Cebu, Guimaras, Leyte, and Samar. Now it is only thought to be found in three to four remaining patches of forest on the islands of Panay and Negros. ("Melbourne Zoo-Flora and Fauna Projects", 1998; Cox, 1987)

Habitat

Visayan spotted deer are most common in the dense interior of the islands. At one time they could be found in larger numbers from sea level to the tops of the mountains throughout the islands. The interiors of the islands are composed of thick rugged tropical forests that range from 750 to 1,000 meters in elevation. The mountains are drained by a series of short violent streams. Visayan spotted deer prefer areas that have undergone a natural disturbance such as fires or landslides. This opens up the canopy allowing the growth of tender plants close to the ground.

A survey in 1991 found that Visayan spotted deer had been extirpated over 95% of its range. The forests are cleared at an excruciating pace by landless peasants and families that were forced into the forest by the collapsing sugar and logging industry. The land that Visayan spotted deer once wandered is now used for farming then abandoned, causing the need for more forest to be cleared. The abandoned agricultural plots are slow to regenerate a secondary forest because of lack of nutrients available in the soil. (Cox, 1987; Heaney and Regalado, 1998)

  • Range elevation
    750 to 1000 m
    2460.63 to 3280.84 ft

Physical Description

Visayan spotted deer have a fine, dense, and soft dark-brown coat on their upper body. They have spots on their backs and flanks, which they retain throughout their life. They have pale white fur on the underside as well as on the chin and lower lip.

Visayan spotted deer are small, the shoulder height of a mature deer is around 75 to 80 cm. Females are much smaller than the males. The ears and tail are relatively short. (Kurt, 1990; Whitehead, 1993)

  • Range mass
    36 to 59 kg
    79.30 to 129.96 lb

Reproduction

The mating system of these deer is not known. However, in other, related deer, the most common mating system is polygyny. Males compete with one another for access to estrous females. Competition often involves sparring and vocalizing. Successful males are typically older and larger, and able to drive away younger, smaller males. These successful males are the ones who mate with the females. It is likely that Visayan spotted deer have a similar mating system. (Nowak, 1999)

The breeding season (rut) of Visayan spotted deer takes place from November to December. Following the breeding season there is a 240 day gestation period, with births in May and June. (Whitehead, 1993)

  • Breeding interval
    Visayan spotted deer breed once yearly.
  • Breeding season
    Breeding occurs in November and December.
  • Range number of offspring
    1 to 2
  • Average number of offspring
    1
  • Average gestation period
    8 months

Information on the parental care of R. alfredi is not available. In most cervids, parental care is strictly by females. Females give birth to one, sometimes two, offspring. The period of nursing lasts from a few weeks to a few months. Young may stay with their mothers past the time of weaning. (Nowak, 1999)

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

Lifespan/Longevity

It is not known how long Visayan spotted deer live. Related deer species can live a maximum of 12-17 years. (Nowak, 1999)

Behavior

Visayan spotted deer are social animals and are generally found in small groups with fewer than eight individuals. Sightings are very rare because of the high hunting pressure and dwindling population. ("Melbourne Zoo-Flora and Fauna Projects", 1998)

Communication and Perception

During the rutting season stag deer will roar. Males are likely to have some physical interactions during the competition associated with rut, if these deer are like other cervids. There are likely some visual and chemical communications from females to males, indicating their estrous status. (Whitehead, 1993)

Food Habits

Visayan spotted deer are herbivores with a diet that includes a wide variety of vegetation. The deer prefer the succulent vegetation that emerges after fires, landslides and other natural disasters. (Heaney and Regalado, 1998; Whitehead, 1993)

  • Plant Foods
  • leaves
  • wood, bark, or stems

Predation

The main predators of Visayan spotted deer are Homo sapiens, (humans). The peasants and other unemployed natives that inhabit the surrounding forest have resorted to hunting as a means of survival. Visayan spotted deer are a protected species but the remoteness of their habitat makes guard patrols very difficult. This puts an increasing pressure on small populations that remain. During the dry season, which is from January until June, hunting pressure is at its highest. (Cox, 1987; Whitehead, 1993)

Ecosystem Roles

It is difficult to speculate on the role that this rare species may play within its ecosystem. Surely, its browsing behavior has some influence on plant communities. It is likely that these deer are able to keep disturbed areas open for longer periods of time by eating down new vegetation. It is also likely that they influence the pattern of ecological succession in the areas of disturbance throught their foraging behavior, probably prefering some types of forage over others.

Economic Importance for Humans: Positive

Visayan spotted deer are a source of food for the native people of the Visayan Islands. Even though it is illegal to kill this species, it doesn’t stop them, and it has a positive effect on their lives by providing food. (Cox, 1987)

  • Positive Impacts
  • food

Economic Importance for Humans: Negative

It is hard to imagine how this species might affect humans negatively. The only possible negative effect would come from enforced protection of the habitat of this animal, which might preclude humans from moving thier subsistence agriculture to more fertile ground. However, there does not seem to be any enforcement of protection of the habitat of R. alfredi.

Conservation Status

Visayan spotted deer are one of the most endangered deer in the world. There are thought to be only a few hundred wild individuals still in existence. This also makes it one of the most endangered mammals in the world. It has a rating of B1 2c on the IUCN categories for critically endangered species. The rating B1 stands for area of occupancy of less than 10 sq km and found in severely fragmented groups. The rating 2c stands for the continuing decline in the quality of habitat. A captive-breeding program was started in 1990 between the Mulhouse Zoo, France and the Philippine Department of Environmental and Natural Resources. The program has grown to three local breeding centers and a number of zoos’s worldwide. The program started with 13 Visayan Deer registered in the international studbook and has since grown to almost 80 registered deer. This species is not listed on any CITES appendix. ("Melbourne Zoo-Flora and Fauna Projects", 1998; Cox, 1987)

Other Comments

The fate of Visayan spotted deer does not look good. If accelerated rates of forest destruction and hunting continue there will be no more deer on the islands in 10 to 15 years. Peasant’s alone account for 50,000 ha of destructed forest land annually. Current practices in the Visayan Islands must change for Visayan spotted deer to make a comeback. The depressed state of the economy and political unrest in the Philippines makes this a difficult task. The deer that are in the captive-breeding programs will not be released until the countryside is able to give them a fair chance for survival. (Cox, 1987; Heaney and Regalado, 1998)

Visayan spotted deer were previously included in the genus Cervus as Cervus alfredi. They have also been considered subspecies of either Cervus mariannus or Cervus unicolor.

Contributors

Nathan Key (author), Humboldt State University, Brian Arbogast (editor), Humboldt State University.

Glossary

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

crepuscular

active at dawn and dusk

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.

folivore

an animal that mainly eats leaves.

food

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

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.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

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

nomadic

generally wanders from place to place, usually within a well-defined range.

oceanic islands

islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

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.

seasonal breeding

breeding is confined to a particular season

sexual

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

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

social

associates with others of its species; forms social groups.

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.

young precocial

young are relatively well-developed when born

References

1998. "Melbourne Zoo-Flora and Fauna Projects" (On-line). Accessed November 13, 2001 at http://www.zoo.org.au/conservation/PSpotDeer.htm.

Cox, R. 1987. The Philippine Spotted Deer & Visayan Warty Pig. ORYX, 21: 37-42.

Heaney, L., J. Regalado. 1998. Vanishing Treasures of the Philippine Rain Forest. Chicago: The Field Museum.

Kurt, F. 1990. Grizimeks Encyclopedia of Mammals. New York: McGraw-Hill Publishing Co..

Massicot, P. "Animal Info-Philippine Spotted Deer" (On-line). Accessed November 3, 2001 at http://www.animalinfo.org/species/artiperi/cervalfr.htm.

Nowak, R. 1999. Walker's Mammals of the World. Baltimore, Maryland: The Johns Hopkins University Press.

Whitehead, K. 1993. The Whitehead Encyclopedia of Deer. Stillwater, MN: Swan Hill Press.