HAIRY-EARED DWARF LEMUR

Allocebus trichotis

Geographic Distribution and Habitat

The hairy-eared dwarf lemur (Allocebus trichotis) is a small primate species local to lowland forests in Madagascar. For more than 20 years, these tiny lemurs were presumed extinct, but they were rediscovered in 1989 near the Mananara River in Northeast Madagascar.

Environmental and human threats are continuously detrimental to the hairy-eared dwarf lemur’s population. Today, they are one of the rarest lemur species and are found exclusively in Madagascar’s national parks and special reserves.

Hairy-eared dwarf lemur range, IUCN 2020

Size, Weight, and Lifespan

Hairy-eared dwarf lemurs are small primates that could fit comfortably in the palm of your hand. Their small stature aids them well when they need to outclimb predators.

Males and females are similar in size, with an average weight of 2.8 oz (80 g) and average length (head and body) of 5.2 in (13.3 cm). Their tails are longer than their body, averaging 6.7 in (17.0 cm).

Although lifespan data for this species is limited, others in the same family can live 15 to 19 years in captivity.

Appearance

Hairy-eared dwarf lemurs are petite primates with small bodies, long reddish-brown tails, and big dark eyes. Their name comes from the long tufts of hair on the front of their short ears. Their coloring is a mix of brownish-gray on their backs and whitish-gray on their fronts. They have pink hands and feet with long fingers that they use to grip onto tree branches. Hairy-eared dwarf lemurs’ tongues are relatively long compared to related species.
Photo credit: © MantellaMan,iNaturalist/Creative Commons
Diet

Hairy-eared dwarf lemurs eat nectar, young leaves, fruit, gums, honey, and insects. They have large upper incisors for scraping tree bark to release plant gums and a long tongue that’s perfect for eating honey in captivity. Between 50 and 70% of their diet in captivity includes locusts that they catch jumping on them.

Behavior and Lifestyle

The arboreal (tree-dwelling) hairy-eared dwarf lemur is active at dusk and ready for sleep by dawn. They are nocturnal and sleep in groups in small tree holes that they furnish with straw or fresh leaves. Groups typically consist of an adult pair and their offspring, but as many as six individuals may sleep together—and fit comfortably!—in a nest.

During the cooler dry season (May to September), the lemurs transition into torpor, a sleep-like state that decreases their body temperature and metabolic rate. As omnivores, this helps them survive when food availability is scarce.

Fun Facts

Hairy-eared dwarf lemurs enter a sleep-like state of pseudo-hibernation, called torpor, during the dry season (May to September). During this period, their body temperature and metabolism decrease to help them store more energy when food is scarce.

Daily Life and Group Dynamics

Hairy-eared dwarf lemurs are active at night and spend their time foraging for food in lower levels of the forest. Groups most often include an adult male, adult female, and their offspring.

Like many other primates, they practice grooming to remove parasites and dead skin. Males and females in captivity will often groom each other before leaving the nest at dusk.

Communication

Not much is known about the hairy-eared dwarf lemur’s communication patterns. Since they are lemurs, they are likely to interact with each other using a combination of body language, vocalizations, touch, and chemical communication. Researchers have collected recordings of them using a short whistling call, similar to the mouse lemur (Microcebus).

Reproduction and Family

Hairy-eared dwarf lemurs are monogamous and reproduce during the wet season. Gestation averages two months, with mating taking place in November and December and births happening in January and February.

Mothers nurse and care for their young until they reach independence (at which age is unknown). Research suggest that males may play a role in childcare by grooming, protecting, and carrying their offspring.

Photo credit: © Frank-Roland Fließ/iNaturalist/Creative Commons
Ecological Role

Hairy-eared dwarf lemurs play two different ecological roles. Since nectar is a big part of their diet, they assist with plant pollination. They can also be prey for carnivores like owls and humans.

Conservation Status and Threats

The International Union for Conservation of Nature lists the hairy-eared dwarf lemur, Allocebus trichotis, as Endangered (IUCN, 2018), appearing on the IUCN Red List of Threatened Species.

Hairy-eared dwarf lemurs are scarce and hard to locate, and the declining small population faces several threats. Deforestation, logging, and slash-and-burn agriculture have cut down their habitat ranges, and they are trapped and hunted for food by local communities. Between 2000 and 2080, it’s estimated that climate change will reduce the hairy-eared dwarf lemur’s range by 64%.

Conservation Efforts

The hairy-eared dwarf lemur, Allocebus trichotis, is listed in Appendix I of the Convention on International Trade in Endangered Species (CITES), an international agreement between governments whose goal is to ensure that international trade in specimens of wild animals and plants does not threaten their survival.

Populations of hairy-eared dwarf lemurs are fragmented, and they are only known to exist in special reserves and five national parks in Madagascar: Mananara-Nord, Mantadia, Marojejy, Masoala, and Zahamena. They are not kept in captivity.

For the survival of the species, hairy-eared dwarf lemurs are in dire need of habitat preservation. Fortunately, the Malagasy government is now making efforts to protect the last portions of virgin lowland forests in the northeastern part of the island.

References:
  • https://animaldiversity.org/accounts/Allocebus_trichotis/
  • https://www.wildmadagascar.org/wildlife/species/Allocebus_trichotis.html
  • https://www.iucnredlist.org/species/868/115559302
  • https://www.animalinfo.org/species/primate/allotric.htm
  • https://www.primatewatching.com/a-trichotis
  • http://www.nocturama.org/wp-content/uploads/2012/03/2009AllocebusTreeHolesBiebouwBearderNekaris1.pdf
  • https://www.researchgate.net/publication/14007908_First_Discovery_of_the_Hairy-Eared_Dwarf_Lemur_Allocebus_trichotis_in_a_Highland_Rain_Forest_of_Eastern_Madagascar

Written by Maria DiCesare, September 2022