Taiwan Serow (Capricornis swinhoei)

The Taiwan serow is the smallest member of the genus Capricornis and an endemite of the main island of Taiwan.

Names

Chinese: 台灣長鬃山羊 (wikipedia)

English: Taiwan Serow [2] Formosan Serow [3]

French: Serow de Taiwan [3], Saro de Taïwan [1]

German: Taiwan-Serau [9], Formosa-Serau [3]

Russian: Тайваньский серау (wikipedia)

Spanish: Sirao de Taiwan [1], Sirao de Formosa [3]

Taxonomy

Capricornus swinhoei Gray, 1862

Type locality: Formosa (Taiwan) [3]

The Taiwan Serow is closely related to the Japanese Serow (C. crispus), but molecular genetic data indicate C. swinhoei is a seperate species. There are also morphological differences: For example cheekteeth are smaller in the Taiwan Serow. [4] Monotipic. [3]

diploid chromosome number: 50 [1, 3]

Similar species

In the wild, no similar species share the range of the Taiwan Serow. The closely related Japanese Serow (C. crispus) is much shaggier and has a larger body size and shorter ears. All other serow species are much larger and have a shaggy mane on the nape of the neck. Gorals (Nemorhaedus sp.) also have a light throat bib, but are generally grayer. [5] Only the Himalayan Brown Goral is similarly rich brown in color. Unlike the Taiwan Serow, gorals do not have visible preorbital glands in front of their eyes. [5]

Distribution

endemic to Taiwan; widely distributed in the mountainous regions throughout the island. [2]; rather in the eastern and central parts of the island

General description

(strongly aberrant figures)

length / head-body: 80-114 cm [3], 95-102 cm [1]

shoulder height: 50-65 cm [3], 67-70 cm [1]

weight: 18-30 kg [3], 30-35 kg [1]

tail: 7-12 cm [3], 6-7,5 cm [1], 6,2-13,7 cm [4]

markings on head: face grey-brown [4]; chin, throat, and posterior jaw pale yellowish to reddish brown [3]; black and yellow markings on the chin, throat and neck, with a large square throat-bib just under the jowls [1]; black zone in the interramal space [4]

ears: relatively large (larger than in Japanese Serow), brown externally, paler internally [1]

horn length: 15-26 cm [3]; 7,4-11,2 cm [1]

pelage characteristics: short, soft and curly; not as bushy as the Japanese Serow [1]; Groves and Grubb (2011) find it rather thick and coarse with much woolly underfur. [4]

pelage colour: brown to dark brown [3], darkish brown to reddish [1], uniform black-brown, brown, reddish brown, or dark brown, with a grayish or reddish tinge [4]

dorsal stripe: narrow, black [1]; thin or unclear, slightly lengthened nuchal stripe [4]

infants pelage: entirely fawn-brown; hair short; white streak behind the corner of the mouth; white patch on the throat; faint dorsal stripe [4]

mane: lacking, unlike in other serows [1, 3, 5]

undersite: slightly lighter, with a reddish tinge in the middle; hinter part of the belly creamy, sometimes suffused with red, going halfway down the inside of the thighs [4]

legs: noticeably darker than body [3]; front of the legs, from the „knee“ and the hock to the hoof, brown or black, this area becoming broader near the hoof; reddish brown at the back of the legs. [4]

sexual dimorphism: very little [1]

Horns

The horns are arched anteroposteriorly, and horn sheaths have a series of transverse rings. Horn length data of Damm, and Franco, 2014 [1] and Wilson and Mittermeier, 2011 [3] is rather contradicting: 7,4-11,2 cm [1] and 15-26 cm [3]. The authors agree in that the Taiwan Serow’s horns are shorter than those of the Japanese Serow.

Little sexual dimorphism is shown and males and females have horns of similar size. Horns of adult males show greater wear than those of females and the grooves of annual rings are more distict in females. The horn formation and wear gives indication of age. Indicators include size, curvature, thickness of transverse horn rings and number of transerse rings. Horns begin to develop at about four months. As adulthood is reached, the thicker transverse rings are forced upward by development of thinner horn rings at the base, and the size of annual growth increments relative to age decreases. [1]

Habitat

Taiwan Serows are adapted to steep and rugged terrain and may use steep and craggy rock faces and cliffs to avoid predators. Since rugged terrain is available independently from elevation, serows occur within a great altitudinal range, from 50 to 3.900 metres, just below the peak of Yu-shan, the highest mountain in the country [2]. Other authers have indicated slightly different figures: 200 to 3.870 m [1, 3]. This altitudinal range is greater than that of the Japanese Serow. [1] Most populations seem to occupy areas higher than 1000 m because of human encroachment [2, 3]. Despite the fact that environmental conditions usually deteriorate with height, populations of Taiwan Serow can be high at high altitudes, particularly in remote areas or in the vicinity of cliffs. [2]

At lower altitudes the Taiwan Serow seems to be even more dependent on areas close to ridges and cliffs. [2]

Because of the great altitudinal range of the Taiwan Serow, the species lives in a wide varity of mountainous habitats, from lowland tropical and subtropical rainforests, mixed broadleaf-conifer forests and warm temperate rainforests at mid-altitudes, to coniferous forests, alpine meadow, and tundra at the highest altitude range. [2]

For two habitat types some characteristic plant species are mentioned. At altitudes higher than 3.000 metres, the Taiwan serow’s habitat is composed of alpine grasslands dominated by Yushania niitakaymensis. In one coniferous forest the following species were found: Formosan juniper (Juniperus formosans), Flaky Juniper (Juniperus squamata), Chinese Hemlock (Tsuga chinensis), and Taiwan Fir (Abies kawakamii). [2]

Mortality / Predators

Mortality related to skin parasites has been reported. [2] The Formosan Clouded Leopard (Neofelis nebulosa brachyura) apparently preyed on Taiwan Serows. [5] This species is believed to be extinct now.

Food and feeding

The Taiwan Serow is „principally a browser“ [3] or an „intermediate feeder“ – between selective browser and roughage eater. [1] Taiwan serows feed on grasses, shrubs, browse, young twigs, some fruits, and even juvenile parts of conifers.

Preferred food plants are (based on information from aborigines): Elatostema edule, Anisogonium esculentum, Begonia laciniata, Polygonum chinensis, Chamabainia cuspidate, Mussaenda parviflora, Perrottetia arisanensis, Pellionia arisanensis and Urtica fissa. [2] Urtica fissa is a stinging nettle species, which the Taiwan Serow eats without ill effects. [1]

Analysis of relationships between forest structures and occurrence frequencies suggested that Taiwan Serows may prefer disturbed and early-succession forests with gaps where they find grass and shrubs to browse. [2]

Breeding

mating: September-December – in captivity [3], September-January, with peak conception from late October to early November [1]

gestation: 210 days [3]

parturition: March-July [3], May [1]

young per birth: 1 [2]; single offspring, twins are rare [1]

weight of newborns: 1,3 kg

Activity patterns

The Taiwan Serow is diurnal and nocturnal, but principally dirurnal [3] – at least in areas with least human activities. [2] It is most active during the 3 hours after sunrise and during the 4 hours before sunset (but lower activity levels than in the morning). Seasonal variations of activity levels were more pronounced in the afternoon. However, Taiwan serow could become more nocturnal in areas close to human activities. [2]

Movements, home range and social organisation

The social system of the Taiwann Serow is probably similar to those of the Japanese Serow, which is basically solitary or found in small groups of up to four individuals. [3] Up to eight animals have been maintained in captive groups. [2]

The Taiwan Serow scent-marks with preorbital glands [2, 3] and has localized dung sites. [2] Male home ranges may overlap with one or two females. [1]

An average density of 22 serows/km² was estimated in part of high altitudes of Yu-shan National Park. [2]

Young Taiwan serows were observed to follow their mothers with occasional hiding behaviour suggesting a follower type. In the wild, young serows had also been photographed by camera traps to follow their parents in spring and fall. [2]

Habitat segregation was found between Taiwan Serow, Sambar Deer (Cervus unicolor swinhoei) and Reeve’s Muntjac (Muntiacus reevesi micrurus). There may be competition in the wild with these species, though the effects of these interactions require further research. [2]

Threats / Conservation Status

The Taiwan Serow is classified as „Least Concern“ on the IUCN Red List. [2]

Greatest concern is the continued degradation and fragmentation of native forests, and agricultural encroachment and related human activities. [3] In addition, heavy poaching pressure over the past decades may have caused the population to decline. [2]

In the past, wildlife was a source of food for the local indigenous people in Taiwan. Because of the growth in the livestock industry over the past 40 years in Taiwan, food from wildlife is becoming less and less important and hunting serow is now banned throughout Taiwan.

However, wild meat is still preferred over livestock meat in certain situations such as ceremonies or gifts. Better economic conditions may also increase the demand for wild meat. Wild meat is still taken through illegal hunting and poaching seems to have increased in recent years, partially because the immigration of foreign workers into Taiwan have caused unemployment among the indigenous people, who have returned to their villages and now practice hunting for a living.

Nevertheless, current poaching pressure still seems lower compared to several decades ago. It is unknown whether current hunting pressure has a significant adverse effects on serow populations. In addition, forestry, agricultural, road construction activities in the mountainous regions have encroached upon the virgin forests originally inhabited by serow.

The latest possible threat to serow comes from increasing recreational and tourist pressures, but the impact is unknown.

Serow populations may be increasing in recent years. Casual observations by park rangers, hikers and wildlife researchers suggest this. However, this impression might be confounded because more people are now involved in outdoor activities. More sightings of serow may lead to a biased impression of increasing populations. Population trends need further research.

Serow is protected in National Parks and in Nature Reserves. Recently, through the development of environmental-protection awareness and enforcement of related wildlife protection laws, conditions for serow have improved. [2]

Hunting

Since 1989, the Taiwan serow has been listed as a “Precious and Rare species” under Taiwan’s Wildlife Protection Act, and hunting the species is prohibited. [2]

Ecotourism

Taiwan Serow watching is not yet considerable, but people do go. There are few reports of people on mammalwatching.com observing serow on the island.

John Wright from the UK reports to have seen 8 serows on a 2,5 hour night drive through Dasyueshan Forest Reserve (east of Fengyuan and Taichung) on July 2016.

Dominique Brugiere from France also visited Dasyueshan Forest in the second half of April in 2016. He saw a total of 13 serows in four days and nights, „mostly at night“, spotlighting along the road.

Bob Hawley (pers. comm.) says „if people want to go out at night looking for serows, then they might find some“, although they can be tricky to see as they’re often on wooded slopes. His experience is that the serows he saw at night did not seem too be perturbed by his presence. He thinks that might be due to low hunting pressure in the parks, and because of the presence of tourists and park workers.

Literature Cited

[1] Damm, Gerhard R. and Franco, Nicolás, 2014: The CIC Caprinae Atlas of the World – CIC International Council for Game and Wildlife Conservation, Budakeszi, Hungary in cooperation with Rowland Ward Publications RSA (Pty) Ltd., Johannesburg, South Africa.

[2] Chiang, P.J. & Pei, K.J-C. 2008. Capricornis swinhoei. The IUCN Red List of Threatened Species 2008: e.T3810A10096148. http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T3810A10096148.en. Downloaded on 12 April 2017.

[3] Wilson, D.E. and Mittermeier, R.A. [eds], 2011: Handbook of the Mammals of the World. Vol. 2. Hoofed Mammals. Lynx Edicions, Barcelona.

[4] Groves, Colin and Grubb, Peter, 2011: Ungulate Taxonomy. The John Hopkins University Press.

[5] Castelló, José R., 2016: Bovids of the World – Antelopes, Gazelles, Cattle, Goats, Sheep, and Relatives. Princton University Press.

[9] Matschei, Christian, 2012: Böcke, Takine und Moschusochsen. Filander Verlag

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