THE AMAZING COMMON BROWN LEMUR

 

The common brown lemur (Eulemur fulvus) is a species of lemur in the family Lemuridae. It is found in Madagascar and Mayotte.^[1]

The common brown lemur lives in western Madagascar north of the Betsiboka River and eastern Madagascar between the Mangoro River and Tsaratanana, as well as in inland Madagascar connecting the eastern and western ranges.^[4] They also live on the island of Mayotte, although this population is believed to have been introduced there by man.^[4]

 

 

Physical description

 

 The common brown lemur has a total length of 84 to 101 cm (33 to 40 in), including 41 to 51 cm (16 to 20 in) of tail.^[5] Weight ranges from 2 to 3 kg (4.4 to 6.6 lb).^[5] The short, dense fur is primarily brown or grey-brown.^[5] The face, muzzle and crown are dark grey or black with paler eyebrow patches, and the eyes are orange-red.^[5]

 

 

Similar lemur species within their range include the mongoose lemur, E. mongoz, in the west and the red-bellied lemur, E. rubriventer, in the east.^[5] They can be distinguished from these species by the fact that E. mongoz is more of a grey color and E. rubriventer is more reddish. There is also some overlap with the black lemur in northeast Madagascar in the Galoko, Manongarivo and Tsaratanana Massifs.^[6] There is also overlap and hybridization with the white-fronted brown lemur, E. albifrons, in the northeast portion of the common brown lemur's range.^[7]

 

 

The common brown lemur's diet consists primarily of fruits, young leaves, and flowers.^[4] In some locations it eats invertebrates, such as cicadas,^[5] spiders^[5] and millipedes.^[8] It also eats bark, sap, soil and red clay (see geophagy).^[8] It can tolerate greater levels of toxic compounds from plants than other lemurs can.^[4][8]

Consistent with its large range, the common brown lemur occupies a variety of forest types, including lowland rainforests, montane rainforests, moist evergreen forests and dry deciduous forests.^[5] They spend about 95% of their time in upper layers of the forest and less than 2% of their time on the ground.^[6]

 

Female with juvenile

both in Peyrieras, Madagascar

They normally live in groups of 5 to 12, but group size can be larger, especially on Mayotte.^[5] Groups occupy home ranges of 1 to 9 hectares in the west, but more than 20 hectares in the east.^[9] Groups include members of both sexes, including juveniles, and there are no discernible dominance hierarchies.^[5]

 

 They are primarily active during the day, but can exhibit cathemeral activity and continue into the night, especially during full moons^[5] and during the dry season.^[4][10]

 

 

In the western part of its range, the common brown lemur overlaps that of the mongoose lemur, and the two species sometimes travel together.^[8] In the areas of overlap, the two species also adapt their activity patterns to avoid conflict.^[10] For example, the Mongoose Lemur can become primarily nocturnal during the dry season in the areas of overlap.

 

  

 Male

At Berenty (south Madagascar) there is a population of introduced E. fulvus rufus x collaris.^[11] These lemurs show linear hierarchy, adult female dominance, and the presence of conciliatory behavior after aggressions.^[12] Additionally, stress levels (measured via self-directed behaviors) decrease at the increase of the hierarchical position of individuals within the social group and reconciliation is able to bring stress down to the baseline levels.^[13]

 

The common brown lemur's mating season is May and June.^[5] After a gestation period of about 120 days, the young are born in September and October.^[5] Single births are most common, but twins have been reported.^[5] The young are weaned after about 4 to 5 months.^[5][8] Sexual maturity occurs at about 18 months,^[5] and females give birth to their first young at 2 years old.^[8] Life span can be as long as 30+ years.^[8]

 

  

 Distribution of E. fulvus:^[1]

 red = native, green = introduced

red = native, green = introduced

THE WOODLY LEMURS

 

The woolly lemurs, also known as avahis or woolly indris, are nine species of strepsirrhine primates in the genus Avahi. Like all other lemurs, they live only on the island of Madagascar.

 

 With a body size of 30 to 50 cm and a weight of 600 to 1200 g, the woolly lemurs are the smallest indriids. Their fur is short and woolly.^[4] The body can be grey brown to reddish, with white on the back of the thighs,^[5] with a long, orange tail. The head is round with a short muzzle and ears hidden in the fur.

 

Woolly lemurs can be found in both humid and dry forests, spending most of their time in the leafy copse. Like many leafeaters, they need long naps to digest their food. Woolly lemurs live together in groups of two to five animals, which often consist of parents and several generations of their offspring.^[6]

 

Like all indriids, the woolly lemurs are strictly herbivorous, eating predominantly leaves, but also buds and, rarely, flowers.

 

Males and females live in pairs. Although likely, the presence of extrapair copulations (which exist in other pair-living nocturnal lemurs, e.g. the Masoala fork-marked lemur (Phaner furcifer)^[7] and the fat-tailed dwarf lemur (Cheirogaleus medius)^[8]) has never been demonstrated in Avahi species. The gestation 

 

period is four to five months, with births usually coming in September. In the first few months, the young rides on the back of its mother. After about six months, it is weaned, and can live independently after a year, although it will typically live for another year in proximity to its mother. Overall life expectancy is not known.

 

On November 11, 2005, a research team that discovered a new species of woolly lemur in 1990 in western Madagascar named the species, Bemaraha woolly lemur (Avahi cleesei), after actor John Cleese, in recognition of Cleese's work to save lemurs in the wild.^[9] In 2006, a taxonomic revision of eastern avahis 

 

 based on genetic and morphological analyses led to the identification of two extra species: A. meridionalis and A. peyrierasi.^[10] Further taxonomic revision increased the number of species, by adding A. ramanantsoavana and A. betsileo.^[11] Finally a new species was discovered in the Masoala peninsula, Moore's woolly lemur (A. mooreorum).^[12]

 

 

 

 

 

 

 

 

 

 

 

 

 

 Combined distribution of Avahi^[2]

 

 

 

 

 

 

THE BLUE -EYED BLACK LEMURS

 

The blue-eyed black lemur (Eulemur flavifrons), also known as the Sclater's lemur, is a species of true lemur. It can attain a body length of 39–45 cm (15–18 in), a tail length of 51–65 cm (20–26 in), a total length of 90–100 cm (35–39 in), and a weight of 1.8–1.9 kg (4.0–4.2 lb).^[4] Being a primate, it has strong hands with palms like a human, which have a rubbery texture to give it a firm grip on branches. Its tail is longer than its body and is non-prehensile.

 

Black-haired male, Bristol Zoo 

Like many of the species in the genus Eulemur, the blue-eyed black lemur is sexually dichromatic. Males are solid black in color, with the hairs sometimes tinged brown at the roots. Females are reddish-brown in color with their underside and outline of their face a lighter tan. They have a dark brown or gray muzzle and the back of their hands and feet are a similar dark color. Both sexes have blue eyes, hence the common name, and are one of the only primates other than humans to consistently have blue eyes. The eyes can range in color from a shocking electric blue, a light sky-blue, or a softer gray-blue.

 

Although the blue-eyed black lemur and the black lemur look similar, they can be differentiated by the blue eyes and lack of prominent ear tufts of this species, while the black lemur has orange-red eyes and long, spiky cheek hairs. In the Manongarivo Special reserve, where the range of the two species overlap, there is a report of hybridization between the two species, but the resulting offspring always have orange eyes. Until 2008, the blue-eyed black lemur was considered a subspecies, E. macaco flavifrons, of the 

 

 The species has not been studied intensively in the wild, but it is known to be fairly social. Group sizes vary from four to eleven individuals on average. Females are dominant as in most lemur species, and there are usually more males than females in each social group. The blue-eyed black lemur is thought to be  

 

polygynous. Females give birth to one or two offspring in June or July, after a gestation of 120 to 129 days. The young are weaned after about 5–6 months, and reach maturity at about 2 years of age. It may live between 15 and 30 years in captivity, with little data recorded on their longevity in the wild. It demonstrates a cathemeral activity pattern, being awake sporadically throughout the day. The occasional nighttime activities are thought to be based on the intensity of the moonlight.^[1]

 

The blue-eyed black lemur communicates with scent-marking, vocalizations, and perhaps some facial expressions. Scent marking is an important means of communication as with most lemur species. Both genders will mark on trees with anogenital glands, while males will also mark using wrist and palm glands 

 

by rubbing and twisting them against leaves, twigs or branches. Males also use a scent gland on the top of their head to mark, lowering their head and rubbing in quick sliding motions.^[5] Little is known of its vocalizations, but it has been observed making a variety of grunts, chirps, barks and clicks. The males are known to make a sharp 'scree' when distressed.

 

The blue-eyed black lemur has also been observed to be a highly aggressive species. There is frequent infighting between troop members, especially during the breeding and birthing seasons. In captivity it has been observed committing infanticide against other species of lemurs, a behavior that is usually uncommon, especially in captivity.

Fruit, pollen, and nectar make up the bulk of this lemur's diet. During the dry season when food is scarce it may eat leaves, seeds and berries and rarely insects. It may also raid farmlands and eat some of the crops, which may lead to it being shot by farmers.^[6]

 

The blue-eyed black lemur helps propagate many rain forest plants. Since it digests the flesh but not the seeds of the fruits it eats, it spreads the seeds of more than 50 different plant species (deposited in a fresh pile of fertilizer), and some plants may have evolved specifically to be dispersed by this lemur.^[7] The blue-eyed black lemur also pollinates many plants while it eats nectar and pollen from the plants' flowers.^[6]

The blue-eyed black lemur inhabits primary and secondary sub-tropical moist and dry forests in the northwestern tip of Madagascar. Its range extends from the Andranomalaza River in the north, to the Maevarano River in the south. Some areas where it can readily be seen are in the forests south of Maromandia near Antsiranana. It may also be seen in the remaining forest patches of the Sahamalaza Peninsula, such as the Ankarafa forest.^[1]

Humans have cut down almost all of this species' habitat to clear farm land. As a result, the blue-eyed black lemur is nearly extinct in the wild. The blue-eyed black lemur is listed on Appendix I of CITES, and is critically endangered.^[1] As few as 1,000 individuals are thought to remain in the wild, largely due to slash and burn habitat destruction, as well as a mild threat from hunting problems.

 

 

Distribution of E. flavifrons^[1]

 

THE BROWN LEMURS

 

True lemurs, also known as brown lemurs, are the lemurs in genus Eulemur. They are medium-sized primates that live exclusively on Madagascar.

 

The fur of the true lemurs is long and usually reddish brown. Often, sexual dimorphism in coloration (sexual dichromatism) is seen, such as in the black lemur. True lemurs are from 30 to 50 cm (12 to 20 in) in length, with a tail that is as long or significantly longer than the body. They weigh from 2 to 4 kg (4 to 9 lb).

 

 

True lemurs are predominantly diurnal forest inhabitants, with some species preferring rain forests, while others live in dry forests. They are skillful climbers and can cross large distances in trees by jumping, using their nonprehensile tails to aid in balancing. When on the ground, they move almost exclusively on all four legs. True lemurs are social animals and live together in groups of two to 15 members.

 

The diet of the true lemurs is almost exclusively herbivorous - flowers, fruits and leaves. In captivity, they have been shown to also eat insects.

 

 

Gestation is 125 days. During the summer or early fall (shortly before the beginning of the rainy season), the females birth their young, usually two offspring. The young clasp firmly to the fur of their mother, 

 

then ride on her back when they are older. After about five months, they are weaned, and they are fully mature around 18 months of age. The life expectancy of the true lemurs can be up to 18 years, but this can be longer in captivity.

 

 

 

 

Range of the fulvus group: red = E. fulvus, green = E. collaris, purple = E. rufus, orange = E. cinereiceps, blue = E. rufifrons, yellow = E. albifrons, brown = E. sanfordi

Range of the other Eulemur: red = E. rubriventer, green = E. mongoz, purple = E. coronatus, orange = E. flavifrons, blue = E. macaco

Common brown lemur (E. fulvus) female with juvenile

References