|Scientific Name:||Diplogale hosei|
|Species Authority:||(Thomas, 1892)|
Hemigalus hosei Thomas, 1892
|Taxonomic Notes:||This species was previously often included in the genus Hemigalus but Corbet and Hill (1992) suggested that morphological differences supported placement in its own genus, Diplogale. Phylogenetic analysis corroborates this (Wilting and Fickel 2012).|
|Red List Category & Criteria:||Vulnerable C1 ver 3.1|
|Assessor(s):||Mathai, J., Duckworth, J.W., Wilting, A., Hearn, A. & Brodie, J.|
|Contributor(s):||Hon, J. & Azlan, M.J.|
Hose's Civet is listed as Vulnerable because its population is likely to be lower than 10,000 mature individuals, based on an area of occupancy (AOO) estimated as 28,000 km²; the assumption of a very patchy distribution even within this area; an indicative population density of one individual per km² (based on studies of similar-sized, largely ground-dwelling civets such as Malay Civet Viverra tangalunga in Borneo; e.g., Colón 2002) in areas considered highly ‘suitable’ for the species; and the very low detection rates in other areas suggesting overall density to be much below this. It is also estimated that there will be an ongoing population decline of at least 10% over the next three generations (taken as 15 years). This decline is expected because of increased pressure on higher-elevation forests as a result of expansion of logging activities and monoculture plantations to higher elevations, coupled with increase in shifting agriculture and indiscriminate hunting practices using nets and snares as a result of human displacement caused by mega hydro-electric dam projects in the centre of Borneo. The combination of such human-induced activities poses the threat of a highly fragmented landscape through which habitat specialists such as Hose’s Civet may be less able to disperse than at present, leading to increasingly isolated populations. Although there are no figures to support this ongoing decline in population size, it is precautionary to acknowledge that these threats will probably take place within the next 15 years, and so to classify the species as Vulnerable.
|Previously published Red List assessments:||
|Range Description:||The cryptic and elusive Hose's Civet is endemic to Borneo. It has been found in Brunei Darussalam, Kalimantan (Indonesian Borneo – one record only; photographically validated; Samejima and Semiadi 2012) and Sabah and Sarawak (Malaysian Borneo). Records suggest it has a highly restricted and patchy distribution within the higher-elevation forests of interior Borneo, with occasional records at lower altitudes (Jennings et al. 2013, Mathai et al. in prep.). It appears to exhibit little habitat plasticity with records mainly in natural forest (e.g., Yasuma 2004; Wells et al. 2005; Mathai et al. 2010a,b; Brodie and Giordano 2010; Matsubayashi et al. 2011) and rarely in logged-over forest (Samejima and Semiadi 2012, J. Mathai pers. comm. 2014); the species' use of recently abandoned or current shifting agriculture and monoculture plantations remains unknown, given the low survey effort in them. The full elevational range of existing records extends from 325 m (Samejima and Semiadi 2012) to 1,700 m a.s.l. (Dinets 2003). Most of the population may occur above 800 m a.s.l., based on the paucity of lower records despite high relevant survey effort there.
In Brunei, the species has been recorded in Ulu Temburung National Park at 450 m and 1,500 m a.s.l. (Francis 2002, Yasuma 2004). This, the largest protected area in the country, comprises lowland, upland and montane forest and is the site of the only live capture anywhere in its world range by 2014 (Yasuma 2004). Brunei remains poorly surveyed and Hose’s Civet should not at present be assumed to be restricted in the country to Ulu Temburung National Park. As of mid-2014, the only record from Indonesian Borneo has been from a recently logged (8 years previously) secondary forest in the Schwaner Mountains, Central Kalimantan (Samejima and Semiadi 2012), in 2011 at 325 m a.s.l. which is, as of late 2014, the lowest elevation recorded for the species.
The species has been recorded from a few localities in Sarawak, mainly in the interior north. The holotype is from Mount Dulit in north-eastern Sarawak, collected in 1891 at 1,200 m a.s.l. (Van Rompaey and Azlan 2004). The largest series of collected specimens - four - was from the Kelabit Highlands in northern Sarawak (Davis 1958). A logging concession in the nearby Upper Baram is one of the few places where the species has been among the most commonly camera-trapped small carnivores (Mathai et al. 2010a,b, in prep.) although many of these detections were from pockets of natural forest within the logging concession. The species has also recently been camera-trapped in Pulong Tau National Park and the proposed protected area of Hose Mountains (Brodie et al. in prep).
In Sabah, the species has been recorded from several protected areas: Kinabalu Park (Dinets 2003, Wells et al. 2005); Crocker Range National Park (A.J. Hearn pers. comm. 2014); Tawau Hills National Park (A.J. Hearn pers. comm. 2014); and the Maliau Basin-Imbak Canyon Conservation Area (Brodie and Giordano 2010, Matsubayashi et al. 2011). It has also recently been camera-trapped in the Ulu Padas Forest Reserve (Brodie et al. in prep.). Most of these records are from primary forests at elevations between 500 and 1,500 m a.s.l.
As part of this assessment, a GIS exercise applied data from the Borneo Carnivore Symposium (June 2011) for which a habitat suitability analysis (incorporating a MaxEnt analysis and a respondent opinion assessment) was conducted (Mathai et al. in prep.). This analysis estimated about 28,000 km² of broadly suitable habitat for Hose’s Civet, restricted to the higher-elevation forests of interior Borneo. To estimate the potential habitat loss, the Miettinen (2011) dataset of land-cover change for the years 2000-2010 was used. This analysis estimated that there had been a loss in suitable land-cover classes of 3-7% (1,100 km² to 8,300 km²) during this period.
Native:Brunei Darussalam; Indonesia (Kalimantan); Malaysia (Sabah, Sarawak)
|Estimated area of occupancy (AOO) - km2:||28000|
|Continuing decline in area of occupancy (AOO):||Yes|
|Extreme fluctuations in area of occupancy (AOO):||Unknown|
|Estimated extent of occurrence (EOO) - km2:|
|Continuing decline in extent of occurrence (EOO):||No|
|Extreme fluctuations in extent of occurrence (EOO):||No|
|Continuing decline in number of locations:||Yes|
|Extreme fluctuations in the number of locations:||Unknown|
|Lower elevation limit (metres):||325|
|Upper elevation limit (metres):||1700|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||There is almost no information on population estimates and breeding status of Hose’s Civet. It has rarely been detected; with the increasing number of studies in Borneo using camera-traps, encounter rates remain very low. The paucity of research on the species prevents reliable quantitative estimates. The wide altitudinal spread of records suggest that the species ought to be common in collections; the fact that it is not suggests very strongly that something renders it very localised, very low density, or both. Moreover, the large survey effort by capable researchers using appropriate techniques in areas that seemingly ought to hold the species (forest within the documented altitudinal and geographic range), still yield low encounter rates (if at all), further corroborating the hypothesis of a highly patchy distribution and low density. Unlike other civets, this species is apparently seldom encountered by native hunters. Again, this gives credence to the hypothesis of patchy distribution and low density, although other explanations are possible such as, until recently, local hunters not venturing far from their villages or high into the mountains when hunting.
As part of this assessment, a GIS exercise applying data from the Borneo Carnivore Symposium (June 2011), for which a habitat suitability analysis (incorporating a MaxEnt analysis and a respondent opinion assessment) was conducted (Mathai et al. in prep.), estimated about 28,000 km² of broadly suitable habitat for Hose’s Civet, restricted to the higher-elevation forests of interior Borneo. Assuming that about two-thirds of the population are mature individuals, this would give a total of roughly 19,000 mature individuals if the population density is taken at 1 individual per km². For a ground-dwelling small carnivore with very low encounter rates, this density is likely to be much at the higher end (see Colón 2002 for a study on the much more frequently encountered Malay Civet Viverra tangalunga in Borneo). Hence, it is likely that the overall density in this 28,000 km² area is 0.5 individuals per km² (or less), giving a population size of less than 10,000 mature individuals.
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||The few records of Hose’s Civet and the paucity of research on the species render its habitat preference and ecology difficult to characterise. The full elevational range of existing records extends from 325 m (Samejima and Semiadi 2012) to 1,700 m a.s.l. (Dinets 2003) though whether this upper limit of 1,700 m is a real guideline occurrence limit or simply an artefact of search effort patterns remains to be ascertained. Current records suggest that a large proportion of the species may occur at elevations above 800 m. However, Samejima and Semiadi (2012) suggest that in some parts of the species’s range, such as the Schwaner Mountains in Central Kalimantan, areas below 450 m may be part of its main habitat. Hose’s Civet appears to exhibit little habitat plasticity with records mainly in natural forest (e.g., Yasuma 2004; Wells et al. 2005; Mathai et al. 2010a,b; Brodie and Giordano 2010; Matsubayashi et al. 2011) and rarely in logged-over forest (Samejima and Semiadi 2012, J. Mathai pers. comm. 2014). In a logging concession in the Upper Baram, Sarawak, for example, the species has been detected in logged forest (less than 10 years previously) where reduced-impact-logging techniques have been applied; frequency of detection is, however, much lower than in primary forest in the same logging concession (J. Mathai pers. comm. 2014). The species’s use of recently abandoned or current shifting agriculture and monoculture plantations remains unknown, given the low survey effort in them. The species is strictly nocturnal and thought to be primarily solitary and ground-dwelling. Its partly webbed feet and hair between its footpads have been speculated to be adaptations towards foraging among mossy streams and boulders (Payne et al. 1985); recent studies appear to corroborate this with the species's presence being positively correlated with presence of moss and number of boulders (J. Mathai pers. comm. 2014). Yasuma (2004) speculated that the species dens in holes between rocks and/or tree roots. It is not known what the species eats in the wild. Payne et al. (1985) suggested it forages for small mammals whereas Davis (1958) speculated that it primarily consumes arthropods. Based on captive observations of the single individual ever caught alive, Yasuma (2004) suggested that the species forages on small fish, shrimps, crabs, and frogs near streams, or catches insects and other animals on mossy ground.|
|Generation Length (years):||5|
|Use and Trade:||Hose's Civet is taken as part of general mammal hunting for food across its range. There is no evidence of specific targeting by hunters.|
|Major Threat(s):||Because of the few records of Hose’s Civet and the paucity of research on the species, it is difficult to characterise even the current major threats, let alone minor and future ones. Based on the GIS exercise as part of this assessment (see sections on 'Range description' and 'Population' for details of this GIS exercise), it was predicted that between 2000 and 2010, only around 3-7% of forests in potentially suitable land-cover classes were lost. This indicates that deforestation rates within the Bornean central highlands have been low. Although this may be the case, it is projected that higher-elevation forests will come under increasing pressure from the logging industry because much of the lowland forest has already been logged, and also from the expansion of oil palm plantations to higher elevations facilitated by climatic warming and improved cultivars (Brodie in review). Moreover, the construction of several massive hydro-electric dams in central Borneo will cause the displacement of several thousand indigenous people; this, in turn, is predicted to increase levels of unsustainable and indiscriminate hunting practices such as the use of nets and snares to which many largely ground-dwelling species, plausibly including Hose’s Civet, are highly susceptible. Human displacement caused by hydroelectric dams is also projected to increase shifting agriculture at higher elevations and this, coupled with habitat loss through infrastructure development linked to the dams, logging and oil palm expansion, poses the threat of a fragmented landscape through which habitat specialists such as Hose’s Civet might be less able to disperse than at present, leading to increasingly isolated populations. Based on a combination of such threats, a decline of more than 10% in the Hose’s Civet population is very likely over the next 15 years (approximately three generations).|
|Conservation Actions:||Hose’s Civet is not a CITES-listed species (CITES 2014), presumably because it is unlikely to feature in international trade owing to its rarity and rather plain pelage (Mathai et al. in prep). The species was listed as ‘threatened’ in the IUCN Action Plan for the Conservation of Mustelids and Viverrids as it was (then) known from only 15 specimens worldwide and there were, at that point, no direct sighting records of a live, wild individual (Schreiber et al. 1989). It is found in some protected areas within its range such as Pulong Tau National Park in Sarawak (Brodie et al. in prep.), Ulu Temburong National Park in Brunei (Yasuma 2004), Kinabalu Park (Dinets 2003, Wells et al. 2005), Crocker Range National Park (A.J. Hearn pers. comm. 2014), Tawau Hills National Park (A.J. Hearn pers. comm. 2014), and the Maliau Basin-Imbak Canyon Conservation Area (Brodie and Giordano 2010, Matsubayashi et al. 2011) in Sabah. However, it is not known how large any of these populations may be or whether any of them are viable populations. Possible strongholds where conservation efforts should arguably be concentrated have been identified (Mathai et al. in prep.) although more research is required to ascertain population status in these areas to verify this. In Malaysian Borneo, the species is listed as ‘Protected’ under the Sarawak Wild Life Protection Ordinance (1998) and the Sabah Wildlife Conservation Enactment (1997), implying limited protection. However, the species is not listed as a protected animal in Brunei under the Brunei Wild Life Protection Act (1978) nor Indonesian Borneo under the Appendix of the Government of Republic of Indonesia Regulation No. 7 (1999).|
|Citation:||Mathai, J., Duckworth, J.W., Wilting, A., Hearn, A. & Brodie, J. 2015. Diplogale hosei. The IUCN Red List of Threatened Species 2015: e.T6635A45197564. . Downloaded on 29 June 2016.|