The Sangihe tarsier ( (Shekelle and Salim, 2013)) is endemic to Sangihe Island of North Sulawesi, which is a small island in Indonesia that span an area approximately 576km^2. This island is located directly east of the Caleb Sea and southwest of Philippine Sea on the eastern side of the Indonesian archipelago.
Sangihe tarsiers live in a subtropical/tropical climate with some climatic variation between the dry and wet season. They have been found normally in groups of 2-6 primates in coconut trees (Cocos nucifera), bamboo (Bambusa vulgaris), vines, and brush. Sangihe tarsiers are limited to patches of forest, shrubs, and wetlands around agricultural areas, farms and villages. Before human disturbance, they would have roamed in the islands primary forests, which have now mostly been destroyed. The Sangihe Island has an elevation range from below sea level up to approximately 1,524m. This tarsier is found below 1500m, and is considered a lowland species. (Gursky, et al., 2008; Shekelle and Salim, 2013; Shekelle, et al., 2008; Shekelle, 2013)
Once a subspecies of spectral tarsier (Tarsius tarsier) until 2008, Sangihe tarsiers are considered a distinct species. They have large bulging eyes, and weigh between 120-160g as adults, males sometimes outweighing females. Their body is approximately 12-13cm long. They have short golden brown/black/grey coats with some white located on the stomach. Their tail, approximately 300mm long, is somewhat scaly but very long in length compared to body size. Because tarsiers are normally vertically clinging to branches and trees, they have long, cushioned palm and fingers for great hold. Sangihe tarsiers are known for their large skulls with the longest tails of the tarsier species. They are also known to have less woolly fur on the body, tail, and appendages compared to other tarsier species. No information on juveniles’ physical description was found. (Shekelle, et al., 2008; Shekelle, 2013; Yustian, 2007)
Sangihe tarsiers typically live with their mate and are monogamous, but some live in a group where one male mates with a few females. Polygynandrous activities also have been recorded in a tarsier group. This structure depends on the structure and number of individuals in the population. In the Sangihe islands, seasonal changes do not occur, so tarsiers mate year-round. (Mitani, et al., 2012)
Tarsiers breed once a year, sometimes twice a year. They are not confined to a specific breeding season. Most female Sangihe tarsiers mate and have a single offspring each year. At birth, offspring are approximately 25% of female weight. The female tends to leave the young at night in a hidden area while she feeds. The gestational period of Sangihe tarsier’ was not found but the related spectral tarsier (Tarsius tarsier) is on average 178-191 days. Weaning of the offspring occurs approximately 80 days after birth. Female tarsiers typically become sexually mature at 2.5 years of age. (Mitani, et al., 2012; Neri-Arboleda, et al., 2002)
Female Sangihe tarsiers tend to be the main caregivers of the offspring including, carrying, feeding and grooming. Males have been recorded to protect, carry and groom the young in some instances. Offspring tend to stay in the social group of the parents post-independence. Time to weaning is 80 days after birth. (Mitani, et al., 2012)
The lifespan on longevity of the Sangihe tarsier is not known. But, other members of the genus such as the spectral tarsier (Tarsius tarsier) and Philippine tarsier (Tarsius syrichta) have an average lifespan of 12-15 years old in captivity. In the wild, for reference, Horsfield's tarsier (Tarsius bancanus) lives for 8 years. (Carey and Judge, 2000)
All tarsiers are arboreal, mostly staying in the trees during every stage of their lives. In the early mornings and late evenings, male and female Sangihe tarsiers communicate through mating calls. They form social groups of about one male and a few females with their offspring. These nocturnal and arboreal tarsiers spend their nights scavenging for food in groups, mostly feeding on insects and small prey while clinging to trees and branches. Males and females both use scent to mark territory, and message their sex, health, and other specifics. (Merker, et al., 2005; Neri-Arboleda, et al., 2002)
The home range of the Sangihe tarsier has not been specially found, but they have been recorded to make nightly paths which range from 1119m – 1636m per individual. (Merker, et al., 2005; Neri-Arboleda, et al., 2002)
Tarsiers generally socialize and forage in groups. They reside mostly in treetops. Male and female Sangihe tarsiers have a mate recognition system that happens only during mornings and evenings. Females call out two-note sounds while males reply with a single note sound.
Sangihe tarsiers are different than other species of tarsiers which typically have only one-noted sounds for both males are females. These vocal duets are repeated multiple times, females having a whistle note while males have a chirping note. In a threatening situation, they communicate by vocal sounds as well.
Sangihe tarsiers have a lingering scent that they use for communication and documenting territories. This scent is unique to each tarsier and helps with individual recognition. (Shekelle, et al., 2008; Shekelle, 2008; Shekelle, 2013; Yustian, 2007)
Tarsiers mostly forage on insects including moths, grasshoppers, ants, and beetles. They also ingest small vertebrates like birds and lizards. Sangihe tarsiers have been noted to forage in groups. In captivity, individual tarsiers have been reported to consume diets of 48% crickets, 24% worms, 24% grasshoppers, and 4% geckos. Daily intake is about 10-12g a day. (Dahang, et al., 2008; Shekelle and Salim, 2013; Yustian, 2007)
Humans (Homo sapiens) have one of the largest impacts on the Sangihe tarsier hunting them for bush meat. Feral cats (Felis catus), snakes, Asian palm civets (Paradoxurus hermaphroditus), and birds of prey are also known to hunt tarsiers. The brown/grey color of the Sangihe tarsier’s fur helps them camouflage into the trees and foliage to protect them from predators. Also, being arboreal keeps them out of reach from ground predators. (Dahang, et al., 2008; Merker, et al., 2005)
Primates, including Sangihe tarsiers, are important for pollination and seed dispersal of their habitat. Sangihe tarsiers also play the role as prey to feral cats (Felis catus), species of arboreal snakes, Asian palm civets (Paradoxurus hermaphroditus), and birds of prey. Parasite information was not found for the Sangihe tarsier. (Dahang, et al., 2008; Merker, et al., 2005)
Local people of the Sangihe Island trade and use the Sangihe tarsier for bush meat. Also, locals use the Sangihe tarsier for ecotourism to educate the public about this species in a conservation effort. (Shekelle, 2013)
There are no known adverse economic effects ofon humans.
On IUCN Red List, Sangihe tarsiers are listed as “Endangered.” CITES listed them under Appendix II, meaning, trading of the Sangihe tarsiers is controlled to ensure survival. National conservation laws have been in place for the Sangihe tarsier since 1931. Also, conservation outreach has been in place to educate local people on environmental issues and management systems on the island. As an endangered species, a breeding program has been in place to help sustain the population. Researchers believe the population is only going to decline due to habitat fragmentation (CITES, 2016; Shekelle, 2013)
Miriam Minich (author), Radford University - Fall 2015, Cari Mcgregor (editor), Radford University, Zeb Pike (editor), Radford University, Karen Powers (editor), Radford University, April Tingle (editor), Radford University, Jacob Vaught (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.
uses sound to communicate
living in landscapes dominated by human agriculture.
Referring to an animal that lives in trees; tree-climbing.
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.
an animal that mainly eats meat
uses smells or other chemicals to communicate
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.
to jointly display, usually with sounds in a highly coordinated fashion, at the same time as one other individual of the same species, often a mate
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.
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.
parental care is carried out by females
A substance that provides both nutrients and energy to a living thing.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
An animal that eats mainly insects or spiders.
animals that live only on an island or set of islands.
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).
parental care is carried out by males
marshes are wetland areas often dominated by grasses and reeds.
Having one mate at a time.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
found in the oriental region of the world. In other words, India and southeast Asia.
chemicals released into air or water that are detected by and responded to by other animals of the same species
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
having more than one female as a mate at one time
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.
communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
associates with others of its species; forms social groups.
uses touch to communicate
Living on the ground.
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
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
breeding takes place throughout the year
CITES, 2016. "How CITES works" (On-line). Accessed March 25, 2016 at https://cites.org/eng/disc/how.phphttp://www.edgeofexistence.org/mammals/species_info.php?id=1420.
Carey, J., D. Judge. 2000. Longevity Records: Life Span of Mammals, Birds, Amphibians, Reptiles, and Fish. Denmark: Odense University Press.
Dahang, D., K. Severn, M. Shekelle. 2008. Eastern tarsiers in captivity, part II: A preliminary assessment of diet. Pp. 97-103 in M Shekelle, I Maryanto, C Groves, H Schulze, H Fitch-Snyder, eds. Primates of the Oriental Night. West Java: LIPI Press.
Gaffney, R. 2011. Risks to Global Primate Diversity from Climate Change and Others Pressures. Durham University: Durham theses.
Gursky, S., M. Shekelle, A. Nietsch. 2008. The conservation status of Indonesia's tarsiers. Pp. 105-114 in M Shekelle, I Maryanto, C Groves, H Schulze, H Fitch-Snyder, eds. Primates of the Oriental Night. West Java: LIPI Press.
Merker, S., I. Yustian, M. Mühlenberg. 2005. Responding to forest degradation: altered habitat use by Dian’s tarsier Tarsius dianae in Sulawesi, Indonesia. Oryx, 39/2: 189-195.
Mitani, J., J. Call, P. Kappeler, R. Palombit, J. Silk. 2012. The Evolution of Primate Societies. Chicago, Illinois: University of Chicago Press.
Neri-Arboleda, I., P. Stott, N. Arboleda. 2002. Home ranges, spatial movements and habitat associations of the Philippine tarsier (Tarsius syrichta) in Corella, Bohol. Journal of Zoology, 257: 387-402.
Shekelle, M., A. Salim. 2013. "Tarsius sangirensis" (On-line). The IUCN Red List of Threatened Species 2013: e.T21493A9289573. Accessed January 28, 2016 at http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T21493A9289573.en.
Shekelle, M. 2008. Distribution of tarsiers acoustic forms, north and central Sulawesi: With notes on the primary taxonomy of Sulawesi's tarsiers. Pp. 35-50 in M Shekelle, I Maryanto, C Groves, H Schulze, H Fitch-Snyder, eds. Primates of the Oriental Night. West Java: LIPI Press.
Shekelle, M. 2013. Observations of wild Sangihe Island tarisers. Asian Primates Journal, 3/1: 18-23.
Shekelle, M., C. Groves, S. Merker, J. Supriatna. 2008. Tarsius tumpara: A new tarsier species from Siau Island, North Sulawesi. Primate Conservation, 23: 55-64.
Shekelle, M., A. Salim. 2009. An acute conservation threat to two tarsier species in the Sangihe Island chain, North Sulawesi, Indonesia. Fauna and Flora International, 43/3: 419-426.
Yustian, I. 2007. Ecology & Conservation Status of Belitung Tarsier. Germany: Cuviller Verlag.