Map_thumbnail_large_font

Hapalemur occidentalis

Status_ne_offStatus_dd_offStatus_lc_offStatus_nt_offStatus_vu_onStatus_en_offStatus_cr_offStatus_ew_offStatus_ex_off

Taxonomy [top]

Kingdom Phylum Class Order Family
ANIMALIA CHORDATA MAMMALIA PRIMATES LEMURIDAE

Scientific Name: Hapalemur occidentalis
Species Authority: Rumpler, 1975
Common Name(s):
English Sambirano Lesser Bamboo Lemur, Western Grey Bamboo Lemur, Western Gentle Lemur, Western Lesser Bamboo Lemur

Assessment Information [top]

Red List Category & Criteria: Vulnerable A2cd ver 3.1
Year Published: 2014
Date Assessed: 2012-07-11
Assessor(s): Andriaholinirina, N., Baden, A., Blanco, M., Chikhi, L., Cooke, A., Davies, N., Dolch, R., Donati, G., Ganzhorn, J., Golden, C., Groeneveld, L.F., Hapke, A., Irwin, M., Johnson, S., Kappeler, P., King, T., Lewis, R., Louis, E.E., Markolf, M., Mass, V., Mittermeier, R.A., Nichols, R., Patel, E., Rabarivola, C.J., Raharivololona, B., Rajaobelina, S., Rakotoarisoa, G., Rakotomanga, B., Rakotonanahary, J., Rakotondrainibe, H., Rakotondratsimba, G., Rakotondratsimba, M., Rakotonirina, L., Ralainasolo, F.B., Ralison, J., Ramahaleo, T., Ranaivoarisoa, J.F., Randrianahaleo, S.I., Randrianambinina, B., Randrianarimanana, L., Randrianasolo, H., Randriatahina, G., Rasamimananana, H., Rasolofoharivelo, T., Rasoloharijaona, S., Ratelolahy, F., Ratsimbazafy, J., Ratsimbazafy, N., Razafindraibe, H., Razafindramanana, J., Rowe, N., Salmona, J., Seiler, M., Volampeno, S., Wright, P., Youssouf, J., Zaonarivelo, J. & Zaramody, A.
Reviewer(s): Schwitzer, C. & Molur, S.
Facilitator/Compiler(s): Chiozza, F.
Justification:
Listed as Vulnerable as the species is suspected to have undergone a population decline of ≥30% over a period of 24 years (three generations), due primarily to continuing decline in area, extent and quality of habitat, in addition to exploitation through unsustainable hunting pressure. These causes have not ceased, and will to a large extent not be easily reversible.
History:
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable (Groombridge 1994)
1990 Vulnerable (IUCN 1990)
1990 Vulnerable (IUCN 1990)

Geographic Range [top]

Range Description: This species is found in north Madagascar. Found in a number of discontinuous pockets in northeastern and northwestern Madagascar. It is known (at least formerly) from the forests of Ankarana and Analamerana in the far north (and possibly in the Ankarana Massif as well); the Sambirano region (from south of Maromandia north through Beramanja and other areas west), the Ampasindava Peninsula, and the Sahamalaza region (north of the Andranomalaza River) in the northwest; the Tsiombikibo, Baie de Baly, Tsingy de Namaroka and Bongolava regions in the central-west between the Mahavavy and Tsiribihina Rivers; Masoala, Maroansetra and Ile Roger (Aye-aye Island) in the northeast; and as far south as Zahamena and Marovohangy near Lake Alaotra (Tattersall 1982; Hawkins et al. 1990, 1998; Rakotoarison et al. 1993; Curtis et al. 1995; Rabarivola et al. 2007; C. Schwitzer, pers. obs.).
 
Razanatsila (2012) reports that the species is easy to see in Nosy Faly Peninsula and Manongarivo Special reserve. Recent surveys demonstrate the presence of the species in many unprotected forests in the northern area of the island including the regions of Sava, Sofia and Diana: Beramanja, Ileviky (Ambilobe), Antsakay-Kalabenono, Bobakindro, Fanambana, Andrakata and Antalaha. The species is also seen in Bealanana corridor.
Countries:
Native:
Madagascar
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: Densities are 50 individuals/km2 in Nosy Faly peninsula, and 71 individuals/km2 in Manongarivo Special reserve (Rakotonarivo et al. 2011).
Population Trend: Decreasing

Habitat and Ecology [top]

Habitat and Ecology: An inhabitant of dry deciduous forest and humid forest containing stands of bamboo and areas of bamboo vines (Tattersall 1982). The species also occurs in marginal, degraded habitats in the Sambirano River valley, as well as in patches of bamboo surrounded by agricultural land and rice fields (Rakotonarivo et al. 2011, Razanatsila 2012). It is reported as being active mainly at night, with groups of six individuals recorded (Mutschler and Tan 2003). Individuals have been observed eating fruits, bamboo and liana flowers. In the northern highland regions of Marojejy and Tsaratanana the bamboo species Ochlandra capitata, Phyllostachys aurea, and Dendrocalamus giganteus are an important food source. The birth season is roughly October–January, following a gestation of 137–140 days (Pollock 1986, Tan 2000). Single infants are the rule, and the interbirth interval is typically one year.
Systems: Terrestrial

Use and Trade [top]

Use and Trade: This species is hunted for food.

Threats [top]

Major Threat(s): This species is threatened mainly by habitat loss due to the regular burning of forest to clear pasture for livestock; charcoal production in the west, and mining in Ankarana. Hunting is also a major threat; in Makira, hunting takes place using slingshots, machetes, and firearms. Note that the species is able to survive in degraded habitats, however the presence of bamboo is essential to survival. Slash-and-burn and destruction of the bamboo land therefore constitute the gravest threat to this species.

Conservation Actions [top]

Conservation Actions: This species is listed on Appendix I of CITES. It is reported to occur in eight national parks (Ankarana, Baie de Baly, Mananara-Nord, Marojejy, Masoala, Sahamalaza-Iles Radama, Tsingy de Namoroka, and Zahamena), two strict nature reserves (Tsaratanana and Zahamena), and eight special reserves (Ambatovaky, Analamerana, Anjanaharibe-Sud, Bemarivo, Kasijy, Maningoza, Manongarivo, and Marotandrano) (Nicoll and Langrand 1989, Schmid and Smolker 1998, Hawkins et al. 1998, Thalmann et al. 1999, Randrianarisoa et al. 2001, C. P. Groves pers. comm., Rabarivola et al. 2007, C. Schwitzer, pers. obs.). Recent surveys, however, did not encounter any animals in Analemarana or Ankarana, but only in a single single patch of unprotected forest in the corridor that connects these reserves (Banks 2005). Although the majority of the population of this species apparently exist in protected areas, a greater number of its population live in unprotected sites where other species of lemurs also inhabit. There should be a specific conservation strategy for marginal habitats to save bamboo trees, thus, to ensure the survival of the species’ population. As of 2010, there was a small, non-breeding population of around 18 in various European zoos (C. Schwitzer pers. obs., I. J. Porton pers. comm.). 

Bibliography [top]

Banks, M. A., Ellis, E. R., Antonioand Wright, P. C. 2007. Global population size of a critically endangered lemur, Perrier’s sifaka. Animal Conservation 10: 254-262.

Golden, C. D. 2005. Eaten to endangerment: Mammal hunting and the bushmeat trade in Madagascar’s Makira Forest. Undergraduate Thesis, Harvard University.

IUCN. 2014. The IUCN Red List of Threatened Species. Version 2014.1. Available at: www.iucnredlist.org. (Accessed: 12 June 2014).

Mittermeier, R., Louis, E., Hawkins, F., Langrand, O., Ganzhorn, J., Konstant, W., Rasoloarison, R., Rajaobelina, S. and Richardson, M. 2008. Lemurs of Madagascar, 3rd edition. Conservation International.

Mutschler, T. and Tan, C. L. 2003. Hapalemur, bamboo or gentle lemurs. In: S. M. Goodman and J. P. Benstead (eds), The Natural History of Madagascar, pp. 1324–1329. University of Chicago Press, Chicago, USA.

Rabarivola, C., Prosper, P., Zaramody, A., Andriaholinirina, N. and Hauwy, M. 2007. Cytogenetics and taxonomy of the genus Hapalemur. Lemur News 12: 46-49.

Rakotoarinivo, T.H., Razanatsila, G.X. and Razafindramanana, J. 2011. Population survey of Hapalemur occidentalis at Manongarivo Special Reserve and Ambato-Nosy Faly forest (Ambanja District). Groupe d’Etude et de Recherche sur les Primates de Madagascar..

Razanatsila, G.X. 2012. Rapport d’étude sur la verification de la presence d’Hapalemur occidentalis dans les regions Nord de Madagascar (Boeny, Sofia, Diana et Sava). Groupe d’Etude et de Recherche sur les Primates de Madagascar.

Rumpler, Y. 2004. Complementary approaches of cytogenetics and molecular biology to taxonomy and the study of speciation process in lemurs. Evolutionary Anthropology 13: 67-78.


Citation: Andriaholinirina, N., Baden, A., Blanco, M., Chikhi, L., Cooke, A., Davies, N., Dolch, R., Donati, G., Ganzhorn, J., Golden, C., Groeneveld, L.F., Hapke, A., Irwin, M., Johnson, S., Kappeler, P., King, T., Lewis, R., Louis, E.E., Markolf, M., Mass, V., Mittermeier, R.A., Nichols, R., Patel, E., Rabarivola, C.J., Raharivololona, B., Rajaobelina, S., Rakotoarisoa, G., Rakotomanga, B., Rakotonanahary, J., Rakotondrainibe, H., Rakotondratsimba, G., Rakotondratsimba, M., Rakotonirina, L., Ralainasolo, F.B., Ralison, J., Ramahaleo, T., Ranaivoarisoa, J.F., Randrianahaleo, S.I., Randrianambinina, B., Randrianarimanana, L., Randrianasolo, H., Randriatahina, G., Rasamimananana, H., Rasolofoharivelo, T., Rasoloharijaona, S., Ratelolahy, F., Ratsimbazafy, J., Ratsimbazafy, N., Razafindraibe, H., Razafindramanana, J., Rowe, N., Salmona, J., Seiler, M., Volampeno, S., Wright, P., Youssouf, J., Zaonarivelo, J. & Zaramody, A. 2014. Hapalemur occidentalis. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 02 October 2014.
Disclaimer: To make use of this information, please check the <Terms of Use>.
Feedback: If you see any errors or have any questions or suggestions on what is shown on this page, please fill in the feedback form so that we can correct or extend the information provided