|Scientific Name:||Boulengerula taitana|
|Species Authority:||Loveridge, 1935|
|Red List Category & Criteria:||Endangered B1ab(iii)+2ab(iii) ver 3.1|
|Assessor(s):||IUCN SSC Amphibian Specialist Group|
|Contributor(s):||Gower, D.J., Measey, J., Wilkinson, M., Malonza, P. & Loader, S.|
Listed as Endangered given that its extent of occurrence (EOO) is estimated to be 309 km2, its area of occupancy (AOO) is estimated to be ca 47 km2, it is known from three threat-defined locations, and there is a continuing decline in the area, extent and quality of its habitat in the Taita Hills of Kenya.
|Range Description:||This species is endemic to three of the four Taita Hills: Dawida (2,228 m asl, 38 km2), Mbololo (1,800 m asl, ca 8 km2), and Kasigau (1,645 m asl, 0.85 km2) (Malonza et al. 2010). It is known from about 1,000-1,900 m asl and its range, taken as a proxy for extent of Occurrence (EOO), is estimated to be ca 309 km2, while its area of occupancy (AOO) is estimated to be ca 47 km2 (Malonza et al. 2010). It was previously recorded only from Mbololo and Dawida; the relatively new isolated record from Mount Kasigau comprises a 50 km extension to the south-east of its occurrence (Malonza et al. 2010). Despite this extension, it is considered to have a much more restricted AOO than previously thought, given that more recent, extensive surveys have revealed that it does not occur in large areas of the Taita Hills of suitable altitude as they fall within a rain shadow (J. Measey pers. comm. May 2012). If each of the Taita Hills is considered a threat-defined location, it would occur in three such locations (J. Measey pers. comm. July 2013).
|Range Map:||Click here to open the map viewer and explore range.|
It is locally abundant in Mbololo and Dawida blocks at elevations between 1,230-1,859 m asl, and less so in Mount Kasigau forest from 1,000-1,635 m asl (Malonza et al. 2010). Historical collections at Wundanyi since the 1970s appear to suggest that there there have been no obvious declines in overall population sizes here (M. Wilkinson pers. comm. May 2012). However, there has been a decline at the type locality (summit of Mbololo), which is now a pine plantation, and caecilians have not been located again at this site despite surveys, although they are found below this site (J. Measey pers. comm. May 2012), In addition, recent interviews with local landowners and workers in the area suggest that there have been declines in intensively farmed areas (J. Measey pers. comm. May 2012). Inferences on population declines are based on continuing degradation of habitat. The population is not considered to be severely fragmented.
|Habitat and Ecology:||It is soil-dwelling, living in montane forests and in secondary habitats, including plantation forests and cultivated land (Malonza et al. 2010). It favours moist soils rich in organic matter and can often be found under decomposing leaves, logs and debris, including terrace banana, avocado, at fig tree bases, and it can also be found alongside permanent water, inclusive of drainage channels (Malonza et al. 2010). However, while it is tolerant of low-intensity agricultural practices, surveys indicate that it cannot withstand more intense farming (J. Measey pers. comm. July 2013). It is oviparous with direct development, and is not dependent upon water bodies. Mean egg clutch size is ca five eggs, with an estimated range of 2-9 per clutch (see Malonza et al. 2010 and references therein). Developing offspring actively feed on their mother's skin (Kupfer et al. 2006).|
|Use and Trade:||In the past (2004 assessment) it has been recorded in the international pet trade in very small numbers, but there have been no further records since.|
|Major Threat(s):||Deforestation and increasing intensification of agriculture within its distribution is a threat (J. Measey pers. comm. May 2012). In particular, soil erosion and gully erosion are very serious and of great concern in the Taita Hills (Sirviö et al. 2004), especially on steeper slopes (Malonza et al. 2010), and this was an ongoing threat in 2009 (J. Measey pers. comm. May 2012). This caecilian is commonly found in dark fertile soil, but has not been found in areas where soil erosion has occurred (Malonza et al. 2010).|
The forest fragments on the Taita Hills are protected by the Kenya Forest Service, but they are still subject to disturbance (P. Malonza pers. comm. May 2012). However, current conservation actions are planned to rehabilitate some plantations into suitable habitat (J. Measey pers. comm. May 2012), although this is expected to take many years. Prevention of soil erosion and soil conservation activities are needed. Population monitoring is needed at the type locality.
Channing, A. and Howell, K.M. 2006. Amphibians of East Africa. Edition Chimaira, Frankfurt am Main.
Glaser, H.S.R. 1984. Observations on an abundant caecilian, Afrocaecilia taitana, in Kenya. ASRA Journal: 47.
Gower, D.J. and Wilkinson, M. 2005. Conservation biology of caecilian amphibians. Conservation Biology 19(1): 45-55.
Hebrard, J.J., Maloiy, G.M.O. and Alliangana, D.M.I. 1992. Notes on the habitat and diet of Afrocacilia taitana (Amphibia: Gymnophiona). Journal of Herpetology: 513-515.
Howell, K.M. 1993. Herpetofauna of the eastern African forests. In: Lovett, J.C. and Wasser, S.K. (eds), Biogeography and Ecology of the Rain Forests of Eastern Africa, pp. 173-201. Cambridge University Press, Cambridge.
IUCN. 2013. IUCN Red List of Threatened Species (ver. 2013.2). Available at: http://www.iucnredlist.org. (Accessed: 13 November 2013).
Kupfer, A., Müller, H., Antoniazzi, M.M., Jared, C., Greven, H., Nussbaum, R.A. and Wilkinson, M. 2006. Parental investment by skin feeding in a caecilian amphibian. Nature 440: 926-929.
Malonza, P.K. and Measey, G.J. 2005. Life History of an African caecilian: Boulengerula taitanus Loveridge 1935 (Amphibia Gymnophiona Caeciilidae). Tropical Zoology: 49-66.
Malonza, P.K., Lötters, S. and Measey, G.J. 2010. The montane forest associated amphibian species of the Taita Hills, Kenya. Journal of East African Natural History 99(1): 47-63.
Measey, G.J. 2004. Are caecilians rare? An East African perspective. Journal of East African Natural History: 97-117.
Nussbaum, R.A. and Hinkel, H. 1994. Revision of East African caecilians of the genera Afrocaecilia Taylor and Boulengerula Tornier (Amphibia, Gmnophiona, Caecilidae). Copeia: 750-760.
Sirviö T., Rebeiro-Hargrave, A. & Pellikka, P. 2004. Geoinformation in gully erosion studies in Taita Hills, SE-Kenya, preliminary results. 5th African Association of Remote Sensing of Environment Conference. Nairobi.
Taylor, E.H. 1968. The Caecilians of the World. A Taxonomic Review. University of Kansas Press, Lawrence, Kansas.
|Citation:||IUCN SSC Amphibian Specialist Group 2013. Boulengerula taitana. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 26 November 2014.|