The Natural History of Ring-tailed Lemurs (Lemur catta):
From its characteristic “raccoon look” to the lively social group
dynamics, the ring-tailed lemur (lemur catta) is by far the most
easily recognized and most popular of all the lemur species.
The ring-tailed lemur, first described in 1758 (Linnaeus) is one
of only three monotypic (single type) prosimians species at the
genus level. In the wild, ring-tailed lemurs tolerate an
array of extreme habitats and exhibit a patchy distribution
throughout the southern and southwestern tropical dry forests
and spiny forests of Madagascar. Population densities are
highly variable with highs being reported to be 100
individuals/km2 in dry forests and up to 250 – 600 individuals
/km2 in gallery and secondary forests.
Lemur catta are diurnal (active during the day), not much bigger
than a house cat (approximately 3 kg or 6.5 pounds) and are the
most terrestrial (ground dwelling) of all the lemurs. In the
wild, the ring-tailed troops can range in size from 6 to 30
individuals. However in captivity, troop size is generally
dependent on enclosure size and you typically see pairs, small
family groups and only occasionally large groups of 25 to 30
animals. The ring-tailed lemur’s social group or troop consists
of related adult females (who have a hierarchy and are dominant
to males), unrelated adult males and a mixture of male and
female offspring. A young female will remain with her
natal group (group she was born in) for her lifetime, however
young males reaching sexual maturity (two to three years old)
will transfer out and join other groups in search of unrelated
females to mate with.
When young males transfer out of their natal group they will
often travel in pairs or trios. They work together as a unit
while searching for and eventually integrating into a new group.
If they are successful finding a new group, the first order of
business is to challenge the resident mature males for breeding
rights with the new females. The lemur catta male performs a
very unique behavior when challenging other males called “stink
fighting”. Males utilize wrist and shoulder scent glands to mark
their tails (bringing their tails between their legs and rubbing
scent from their arms on the tail) and then quickly pull their
tail back and throw it up and over their head – shaking it at
the rival male. Males will also demonstrate a more violent
challenge behavior termed “jump fighting”. This behavior is most
often seen during the breeding season and involves high leaps
into the air that are followed by full body aggressive contact
with slashing bites from their incredibly sharp and long
canines. Defeated males will migrate to another group and repeat
the process. Through this emigration and immigration practice,
genetic exchange occurs and inbreeding is avoided.
In the wild, females are not sexually mature until three years
of age. However in captivity females have been known to conceive
as early as one year of age. Mating season in the wild
begins in mid-April however, in North America it begins in
October. Mating activity is highly synchronous both in the wild
and in captivity and often only lasts for a few weeks.
Infants are born, after a gestation period of approximately 135
days. Single infants are most common, followed
closely by twins when food is plentiful. Infants cling to the
female’s abdomen for about two weeks before trying their luck
with the jockey style position. Infants grow very quickly and by
four weeks will venture off their mom and begin to explore their
environment. Females with offspring form a very tight social
unit. They will interact and travel together as well as
share babysitting duties, feed & sleep together. The
sleeping formation is another unique ring-tailed lemur behavior.
Females and offspring will huddle together much like a football
team would, but with tails that are intertwined and held over
one another’s shoulder or back to form a “lemur ball”. All
lemurs face inward with only the backs of the animals on the
outer row exposed to the elements (rain or cold weather).
Unfortunately, mature males are not invited to participate in
the lemur ball and are expected to sleep on their own.
Ring-tailed lemurs also enjoy “sunbathing”. This behavior is not
unique to lemur catta but they seem to perform it best! The
early morning rays of the sun are sought out to begin warming
themselves. Males, females and offspring will sit very still
with perfectly straight backs while facing the sun. Their arms
are positioned outward from each side of the body as if they
were in a yoga pose. This posture permits maximum sunlight
penetration to the black skin just under their dense hair, thus
permitting the animals to warm themselves very quickly.
Ring-tailed lemurs are omnivorous and feed on fruit, leaves,
flowers, herbs and other plant parts. In the wild, the
leaves and fruit of the tamarind tree (Tamarindus indicus) are
favorite foods and can provide approximately 50% of the wild
diet. Ring-tailed lemurs will also supplement their diet
with insects and small vertebrate prey if the opportunity
presents itself. In captivity, ring-tailed lemurs are fed a
commercial chow (nutrient rich biscuit) along with an assortment
of fruits and vegetables. True to their wild cousins, even
captive ring-tailed lemurs will supplement their diet with the
opportunistic capture of “prey”!
Lemur catta groups live in home ranges varying in size from 6ha
to over 30ha – depending on the season and type of habitat.
Females and males define and defend their territory by scent
marking the boundary limits of their home range. Males utilize
their thorny forearm spur and wrist scent gland along with
scrotal glands to embed scent into the bark of trees and shrubs
while the females mark with scent from their vulva. Territorial
disputes will occur when neighboring ring-tailed lemur groups
meet at their range boundaries.
Lemur catta are extremely vocal and have unique calls for
predator species and group communication such as for location,
infant, feeding and lost calls. Vocalizations consist of meows,
clicks, yaps, screams, purring and squeaks. Ring-tailed
lemurs also communicate visually with their tails. As the troop
moves through an area, all tails are held up high and the
characteristic black and white rings serve as “distance signals”
keeping the group together as well as serving as a “presence
signal” to warn off other groups.
Natural predators consist of raptors, fossa (a large civet like
carnivore), Indian civets, ground boas and occasionally feral
dogs and cats.
Further general reading:
Lemur Behavior: A Madagascar Field Study. 1966. Alison Jolly.
Lords and Lemurs: Mad Scientists, Kings With Spears and the
Survival of Diversity in Madagascar. 2004. Alison Jolly
Lemurs of Madagascar, CI Tropical Field Guide Series 2nd edition
2006. Mittermeier, et.al.
Mammals of Madagascar – A Complete Guide, 2007. Nick Garbut
For the enthusiast:
Ringtailed Lemur Biology: lemur catta in Madagascar. 2006. A.
Jolly, R. Sussman, N. Koyama & H. Rasamimanana (Developments in
Primatology: Progress and Prospects series).
The Natural History of Madagascar. 2003. Edited by S. Goodman
and J. Benstead.
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