Observations of Small Carnivores in Son Tra Nature Reserve, a Small and Isolated Protected Area in Central Vietnam
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Observations of small carnivores in Son Tra Nature Reserve, a small and isolated protected area in central Vietnam Ulrike STREICHER1 and Larry ULIBARRI2 Abstract Over half the 45.5 km² Son Tra peninsula in central Vietnam is a nature reserve. The peninsula has been isolated from other natural habitat by sea and urbanisation for decades. Various surveys since the 1960s have recorded Large-toothed Ferret Badger Melogale personata, Small Indian Civet Viverricula indica, Common Palm Civet Paradoxurus hermaphroditus, Small Asian Mongoose Herpestes javanicus and Leopard Cat Prionailurus bengalensis; and probably otter (Lutrinae) and Large Indian Civet Viverra zibetha, although the original basis for these two is not available. Several species typical of forest in this region and active at least in large part by day were not found, suggesting that they are possibly susceptible to hunting or need larger landscapes (or both). None of the surveys targeted small carnivores, so some species, particularly nocturnal ones, might have been overlooked. The easily accessible Son Tra KeywordsNature Reserve: breeding with seasonality,its unusually community, confiding wildlife fragmentation, is ideal for habitat wildlife change, and conservation Herpestes javanicus studies and, locality education. records, Melogale per- sonata, persistence Ghi nhận thú ăn thịt nhỏ ở Khu Bảo tồn Thiên nhiên Sơn Trà, một khu bảo vệ nhỏ và cô lập ở miền trung Việt Nam Tóm tắt Khoảng một nửa diện tích 45,5 km² của bán đảo Sơn Trà ở miền trung Việt Nam là môt khu bảo tồn. Bán đảo đã bị cô lập với các sinh cảnh tự nhiên khác bởi biển và các khu đô thị từ vài thập kỷ nay. Nhiều đợt khảo sát từ những năm 1960 đã ghi nhận Chồn bạc má nam Melogale personata, Cầy hương Viverricula indica, Cầy vòi đốm Paradoxurus hermaphroditus, Cầy lỏn tranh Herpestes javanicus, Mèo rừng Prionailurus bengalensis, và có thể là cả rái cá (Lutrinae) và Cầy giông Viverra zibetha, tuy nhiên cơ sở để khẳng định ghi nhận về hai loài này là chưa chắc chắn. Không có ghi nhận một số loài điển hình cho rừng ở khu vực này nhất là trong thời gian ngày cho thấy chúng rất có thể đang bị đe dọa bởi săn bắn hoặc bị ảnh hưởng do cần diện tích sinh cảnh lớn hơn (hoặc do cả hai nguyên nhân). Chưa có các điều tra tập trung vào các loài thú ăn thịt nhỏ, vì vậy một số loài, nhất là các loài hoạt động về đêm, có thể đã bị bỏ sót. Giao thông thuận tiện đến Khu Bảo tồn Thiên nhiên Sơn Trà và việc dễ tiếp cận các loài động vật hoang dã là điều kiện lý tưởng cho các hoạt động nghiên cứu và giáo dục bảo tồn. Introduction are potentially stable, or represent stages in inevitable decline during a lag to adjust to the new level of habitat availability. Little is known about the adaptability of small carnivores in Southeast Asia to habitat fragmentation and isolation. Most Survey area surveys understandably prioritise large, remote areas (e.g. Than Zaw et al. 2008); but with Southeast Asia having some Son Tra Nature Reserve (NR), central Vietnam, is a perfect of the world’s highest rates of forest clearance (e.g. Sodhi et al. place to document a small carnivore community in a small for- 2010), better information on the ability of its wildlife to per- est isolate. The rocky Son Tra peninsula (16°06–09′N, 108°13– sist in converted, degraded and/or fragmented areas is vital to 21′E) is surrounded on three sides by the South China Sea and inform conservation planning and management. A recent rise - in interest in the region’s small carnivores of converted and de- ang (Fig. 1). The foothill area connecting the nature reserve graded areas (e.g. plantations and logging concessions; Mathai withon the the fourth mainland it borders is very the densely fifth largest populated, city ofwith Vietnam: many roads Dan et al. 2010, Wilting et al. 2010, Hedges et al. 2013) has been and houses, the container harbour and much army infrastruc- concentrated in southern (Sundaic) Southeast Asia and has not ture. There is no real non-urban land on this isthmus, nor any been echoed by equivalent interest in documenting the species forest within almost 15 km. Son Tra has been isolated like this surviving in small, long-isolated, patches. To a certain extent, for at least 50 years. Dispersal opportunities for non-volant, non-urban wildlife to the peninsula have thus been very lim- hunting, widespread in northern SE Asia (e.g. Corlett 2007), ited for decades. Son Tra NR comprises 26.7 km² of the overall this reflects (i) the difficulties of disentangling the effects of 45.5 km² peninsula and contains most of the native forest left isolated area, given that many species are known or reasonably on the peninsula. Son Tra rises from sea level to 696 m asl. It suspectedfrom those to of movehabitat through isolation; otherwise (ii) the challenges unsuitable of habitat; defining and an (iii) the very recent nature of much habitat perturbation, mak- The rainy season lasts from June to January and the dry season ing it unclear whether today’s communities in habitat isolates fromreceives February significantly to May. more rainfall and is cooler than Danang. Small Carnivore Conservation, Vol. 51: 18–22, December 2014 18 Small carnivores in Son Tra NR, Vietnam Fig. 1. The Son Tra peninsula, Vietnam. Left, aerial image: blue = sea, green = vegetation, pale grey = urban and other non-vegetated land. Right, roads (thick black lines) and contours (thin lines; interval 20 m). Based on weather parameters, Son Tra’s forest has wet human voice and scent than is typical elsewhere in Vietnam. tropical semi-evergreen forest with never more than 1.8% Wildlife is therefore more easily spotted. During a long-term of trees shedding at least a quarter of their leaves (Ulibarri ecology study of the Red-shanked Doucs (Ulibarri 2013), qui- 2013). Van Peenen et al. (1971), noting that most of the veg- etly sitting observers were occasionally approached within a etation was heavily disturbed even then, divided the peninsula few meters by various wildlife including Red Muntjac Mun- into tropical primary forest, tropical secondary moist forest, tiacus muntjak, ferret badger Melogale and Small Asian Mon- secondary dry forest and grassland. Son Tra held an Ameri- goose Herpestes javanicus. can military base in the 1960s–1970s. Since the end of the During the 1960s and 1970s, Son Tra was the site of many war it has been an important base for the Vietnamese military. wildlife observations (e.g. Hoogstraal et al. 1968, Van Peenen Several roads cross the reserve. The area has been accessible et al. 1971, Lippold 1977). to the public only since 2007. Most of the local people in this Small carnivore records restrictions and cultural predispositions mean hunting and loggingcoastal areregion much are less fishermen prevalent and than not is hunters.typical in These Vietnam, access re- - - trinae) and Leopard Cat Prionailurus bengalensis, were listed maining population of Red-shanked Douc Pygathrix nemaeus forFive Son species Tra NR of insmall various carnivore, surveys plus (Table unidentified 1). Van Peenen otter et(Lu al. inflected Vietnam most (a clearly species by notoriously the survival sensitive of the secondto even largest moderate re (1971) trapped mammals and made some day-time observa- levels of hunting and hugely declined even in some quite re- tions over four periods within 1966–1969. Specimens were mote large forest blocks; e.g. Coudrat et al. 2012) and a large deposited at the United States National Museum. Between De- population of the Critically Endangered valuable timber tree, cember 1995 and May 1997, Dinh (1997) conducted a compre- White Seraya Parashorea stellata (Ulibarri 2013). hensive survey, but the report does not specify source for each - record, and error-prone methods (e.g. signs and interviews) ing, presence of people, animals in this reserve are less shy of were used. A short survey in 2007 focusing on Red-shanked Reflecting the longstanding large, mostly non-threaten Table 1. Small carnivore species recorded in Son Tra, Vietnam, 1966–2014. Species Source Large-toothed Ferret Badger Melogale personata VP, DTPA*, aro* Otter (Lutrinae) DTPA Large Indian Civet Viverra zibetha DTPA Small Indian Civet Viverricula indica VP, DTPA Common Palm Civet Paradoxurus hermaphroditus VP, DTPA, aro Small Asian Mongoose Herpestes javanicus VP, DTPA, VNT, aro Leopard Cat Prionailurus bengalensis DTPA, aro Sources: VP, Van Peenen et al. 1971; DTPA, Dinh 1997; VNT, Vu et al. 2007; aro, authors’ 2010–2014 observations. *Not confirmed to species; the very similar looking Small-toothed Ferret Badger M. moschata occurs widely in Vietnam (Abramov & Rozhnov 2014) and potentially could also occur on Son Tra. Vu et al. (2007) reported Masked Palm Civet Paguma larvata based on interviews with reserve staff and/or local people. 19 Small Carnivore Conservation, Vol. 51, December 2014 Streicher & Ulibarri and came within arm’s length. The follower, assumed on size to be the male (males are considerably larger than females; Francis 2008), was uttering high-pitched excited noises. The gestation period of Small Asian Mongoose is approximately 49 days (Lekagul & McNeely 1977) and if the observed courting incident was followed by a successful mating, cubs would be born towards the end of May. Consistent with this, an adult Small Asian Mongoose leading two cubs was spotted nearby in late July 2014. Ferret badgers’ gestation period is reported to suggests cubs would be born around mid-October. be about 60–80 days (Smith & Xie 2008), so this observation Discussion Fig.