47.
Lake Alaotra Gentle Lemur
(Hapalemur alaotrensis)
CR
Overview
Described by Gerald Durrell as a ‘honey-coloured teddy bear’, the Alaotran gentle lemur is the only species of primate to occur exclusively in wetlands. Significantly larger than the other species of bamboo lemur, this species uses its grasping hands and feet and long tail to balance when walking along reed stalks in its lakeside habitat. It can also leap from support to support in a vertical posture, landing feet-first, and may possibly be able to swim. Widespread hunting for pelts and cheap meat combined with large scale burning of the reed beds on which it depends has caused a decline of over 50% in a decade. Today only two subpopulations remain.
Urgent Conservation Actions
The overwhelming problem of enforcing the lemur hunting and marsh burning bans must be tackled by either educational or legal means.
Distribution
Madagascar
Media from ARKive
ARKive video - Alaotran gentle lemur - overview
ARKive image - Young Alaotran gentle lemur
ARKive video - Alaotran gentle lemur feeding
ARKive image - Alaotran gentle lemur with young on back
ARKive image - Alaotran gentle lemur with young
ARKive image - Alaotran gentle lemur with young
ARKive image - Alaotran gentle lemur
ARKive image - Alaotran gentle lemur
ARKive image - Alaotran gentle lemurs
ARKive image - Male Alaotran gentle lemur
ARKive image - Female Alaotran gentle lemur
ARKive image - Female Alaotran gentle lemur
ARKive image - Alaotran gentle lemur head profile
ARKive image - Female Alaotran gentle lemur
ARKive image - Alaotran gentle lemur in tree
ARKive image - Alaotran gentle lemur feeding
ARKive image - Alaotran gentle lemur on ground
ARKive image - Alaotran gentle lemur feeding on bamboo
ARKive image - Alaotran gentle lemurs
Evolutionary Distinctiveness
Order: Primates
Family: Lemuridae
Lemurs belong to the suborder Strepsirhini, which also includes bushbabies, pottos and lorises. These groups are the most basal living primates. Ancestral prosimians, possibly resembling today’s mouse lemurs, are thought to have colonised Madagascar from mainland Africa 50-60 million years ago. In the absence of competition from other non-primate mammals, these species diversified to fill a wide range of unusual ecological niches. There are five distinct families of lemurs: Lemuridae, Indriidae, Megaladapidae, Cheirogaleidae and Daubentoniidae. The Lemuridae comprises 10 species, divided into two subfamilies: the Lemurinae (‘true’ lemurs) and the Hapalemurinae (bamboo or gentle lemurs). The Alaotran gentle lemur belongs to the largest of the 5 lemur families, the Lemuridae. This family is comprised of five genera: Hapalemur, Prolemur, Lemur, Varecia and Eulemur. The Alaotran gentle lemur was until recently regarded as a subspecies of the lesser gentle lemur Hapalemur griseus. However, it has recently been reclassified as a distinct species. The Hapalemur genus now contains 5 species, which are collectively known as gentle or bamboo lemurs.
Description
Size: 
Head and body length: ~28cm
Weight: 1-1.4 kg
When Gerald Durrell first encountered these lemurs on his expedition to Madagascar in 1990 he described them as ‘honey-coloured teddy bears’. They have a grey face, ears and chest, and the top of the head, back and tail are golden-brown with a variable amount of grey flecking. Their belly is a light brown ‘camel’ colour and their feet are grey. Gentle lemurs’ eyes are a deep red-brown and females, especially youngsters, often have very pale brown eyebrows. Adult males have enlarged top canine teeth that protrude from their muzzle, that give them a rather fierce expression, contrary to their name.
Ecology
The Alaotran gentle lemur eats a variety of marsh vegetation, with papyrus reeds making up a large proportion of their diet. They live either in monogamous family groups, with one adult breeding pair, or in small groups with two breeding females. The most common group composition was found to be an adult pair and one offspring. As with all lemurs, but unlike other primates, female gentle lemurs are dominant. Groups are highly territorial and adult males behave aggressively when they encounter one another. Breeding is annual and pregnancy lasts for about 5 months. Young are born with open eyes and covered in fur from September through February and twins are common.

Direct observations during daylight hours showed that H. alaotrensis has two main activity periods, early in the morning and late in the afternoon, before dusk, with substantial night activity. It is not known how long gentle lemurs live, however 20-30 years is not unusual for other lemur species in captivity.
Habitat
Uniquely among primates, this species occurs only in marshy habitats. It is restricted to the marshland vegetation surrounding Lake Alaotra in eastern Madagascar, a habitat in which stands of reeds and papyrus are separated by water channels.
Distribution
This species is known only from the papyrus and reed beds surrounding Lac Alaotra, Madagascar’s largest lake located in the eastern rainforest region. The species occurs as two subpopulations, a small one in the northern part of the lake around the Belempona Peninsula and a larger one in the adjoining marshlands along the lake’s south-western shores bounded by the villages of Anororo, Andreba and Andilana-Sud. Its entire range appears to be rather less than 200 km² and it occurs only up to elevations of 750 m.
Population Estimate
Believed to number around 2,500 individuals
Population Trend
Decreasing. This species has experienced a decline of more than 50% in less than a decade.
Status
Classified as Critically Endangered (CR B1ab (iii,v)) on the 2010 IUCN Red List of Threatened Species.
Threats
Although legally protected in Madagascar, gentle lemurs are still poached in large numbers for cheap meat. A variety of hunting and trapping methods are employed by local people. Direct pursuit by dogs is the most common, but they may also be captured by using a harpoon, a snare, a stick to knock them out or into the water, or by burning their reed bed habitat, causing them to flee into the hands of waiting hunters. More than 1000 lemurs have been hunted annually in some years.

Another major problem has been habitat degradation and fragmentation, caused by a variety of processes: silting up of the lake through erosion, lake drainage for irrigation and rice cultivation and annual reed burning to increase access to fish stocks. Much of the original wetland has been converted to rice fields. A principal threat facing the remaining Alaotran wetland is anthropogenic burning of the vegetation during the dry season; a practice now officially banned. Wetland burning facilitates hunting for introduced fish species and is possibly the main reason for ongoing burning.
Conservation Underway
This species is listed on Appendix I of CITES. A captive breeding and research programme was initiated at the Durrell Wildlife Conservation Trust in Jersey in 1990.  Since then a small but self-sustaining population has been created across several European zoos.

In 2003 Lac Alaotra was designated a Ramsar site to provide a framework for protecting the remaining wetland. More recently the government of Madagascar classified the lake as a protected area. This occurred through the work of the Tusk Trust and the Durrell Wildlife Conservation Trust. The Lake Alaotra Protected Area has been designated to conserve the lake, marshes and surrounding watersheds – the critical lemur habitats – and came into force in 2009. The protected areas will be managed collaboratively between community groups and government authorities. Some areas will be strictly protected but the majority of the area will be managed for sustainable use to ensure local people benefit from fishing and marsh products in the long term. No-take zones covering the main fish spawning areas, adjacent to the marsh habitats of the lemurs, have recently been created to aid the recovery of the lake’s fishery.

Public awareness campaigns have focused on benefits of habitat conservation (erosion control, the biological filtering of agricultural pollutants, and flood prevention) to the half million or more people who live by the lake. A regional fishing convention bans lemur hunting and marsh burning.
Conservation Proposed
The overwhelming problem of enforcing the lemur hunting and marsh burning bans must be tackled by either educational or legal means.
Links
Durrell Wildlife Trust                          

Tusk
Zoo population

There is an Alaotran gentle lemur resident at ZSL London Zoo

References
Andrainarivo, C., Andriaholinirina, V.N., Feistner, A., Felix, T., Ganzhorn, J., Garbutt, N., Golden, C., Konstant, B., Louis Jr., E., Meyers, D., Mittermeier, R.A., Perieras, A., Princee, F., Rabarivola, J.C., Rakotosamimanana, B., Rasamimanana, H., Ratsimbazafy, J., Raveloarinoro, G., Razafimanantsoa, A., Rumpler, Y., Schwitzer, C., Thalmann, U., Wilmé, L. & Wright, P. 2008. Hapalemur alaotrensis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. <www.iucnredlist.org>. Downloaded on 15 November 2010.

Copsey, J. A. et al. 2009. Short Communication: Burning to fish: local explanations for wetland burning in Lac Alaotra, Madagascar. Oryx, 43(3): 403–406

Durrell Wildlife Trust Aloatran Gentle Lemur Factsheet.

Hapalemur griseus alaotrensis. Folia Primatol 69:325–330.

Mutschler, T., Feistner, T. C., & Nievergelt, M. 1998. Brief Report: Preliminary Field Data on Group Size, Diet and Activity in the Alaotran Gentle Lemur

if you can provide new information to update this species account or to correct any errors, please email us at info@edgeofexistence.org


Forum comments

There are as yet no comments for this species.

Add a comment

You must log in to post. If you don't have a login, it's easy to register.