Verreauxs sifaka

Propithecus verreauxi

Verreaux's sifaka, or the white sifaka, is a medium sized primate in one of the lemur families, Indriidae. It lives in Madagascar and can be found in a variety of habitats from rainforest to western Madagascar dry deciduous forests and dry and spiny forests. The fur is thick and silky and generally white with brown on the sides, top of the head, and on the arms. Like all sifakas, it has a long tail that it uses as a balance when leaping from tree to tree. However, its body is so highly adapted to an arboreal existence that on the ground its only means of locomotion is hopping. The species lives in small troops which forage for food.

There are four sub-species of this kind of lemur. There are many things unknown about Verreaux's sifaka, so their life span in the wild has not been approximated, but in captivity they generally live to up to 18 years old.
Verreaux's sifaka - closeup 1, Kirindy Reserve, Madagascar A few shots of the largest lemur species to be found in Kirindy Reserve, the Verreaux's sifaka. There are 9 species of Sifaka's (which are named after their call) in Madagascar, here's a useful map showing the distribution of them all:
https://commons.wikimedia.org/wiki/File:Propithecus_species_IUCN_range_map.svg

All species of Sifaka and threatened, mostly by habitat loss due to slash and burn agriculture. It's main natural enemy is the Fossa. 

In behavior, by day this is a slow, inactive herbivore. Their life consists of lazily sitting in trees whilst slowly chewing leafs, after which they take a giant rest from that effort.

One thing they are known for is their weird locomotion at ground level where due to their feet being optimized for life in the trees, they can't really walk or run, instead they hop sideways:
https://www.youtube.com/watch?v=8RiZElNNpAY
https://www.jungledragon.com/image/83136/verreauxs_sifaka_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83132/verreauxs_sifaka_-_wide_eyes_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83133/verreauxs_sifaka_-_closeup_2_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83134/verreauxs_sifaka_-_closeup_3_kirindy_reserve_madagascar.html Africa,Geotagged,Kirindy Reserve,Madagascar,Madagascar 2019,Propithecus verreauxi,Verreauxs sifaka,Winter,World

Appearance

In adulthood the full head and body length is between 42 and 45 cm . The tail of a fully grown Verreaux's sifaka grows to be between 56 and 60 cm long. In terms of weight, adult females reach 3.4 kg on average, and adult males 3.6 kg .

Verreaux's sifaka has a relatively low, flat braincase. The face is broader than that of most other Indriids, but its snout is reduced. This species of sifaka is also distinguished by its unique dentition. Its dental formula is 2.1.2.32.0.2.3. The upper incisors are very small and are slightly angled inward towards the gap between I1 and I2. In the mandible, Verreaux's sifaka displays the stresirhine characteristic: the toothcomb. Formed by the procumbent lower incisor and canine, the toothcomb projects past the front margin of the mouth. ''P. verreauxi'' also presents the high, shearing molar crests of a folivore, helping to shread the leaves, fruit, and flowers that it eats. Postcranially, Verreaux's Sifaka has a low intermembral index that ranges from 63-66. It has a broader ribcage than most other prosimians and has many lumbar vertebrae lending it a lot of flexibility. The pelvic is high and narrow and the acetabulum is relatively shallow, also allowing for greater flexibility. Like other Indriids, ''P. verreauxi'' has a short calcaneus, pointed nails, and slightly webbed hands and feet.
Verreaux's sifaka - siesta, Kirindy Reserve, Madagascar Another series of this friendly tree grazer, the Verreauxs sifaka. This time I dug up some info on their social system.

Like many lemur species, they live in a female dominant society, where females vastly outnumber males. Typically, in a full group there may be up to 7 females, 3 males, and a few young. One theory for this female dominance is based on the lack of sexual dimorphism. Males and females are roughly of equal size, weight and strength, therefore dominance is based on reproductive value, not physical strength.

However, there is still a dominant male. Out of the 3 males, one will be dominant and will have exclusive mating rights with all adult females in the group. The dominant male can be recognized by its dark patch on the chest. Not to be confused by simply having a dark chest, as this is not a patch, it is  simply their dark skin shining through the fur. 

The other males are called "clean-chested". Groups are usually peaceful where everybody knows their place, except for during the breeding season, where the dominant male may be challenged.
https://www.jungledragon.com/image/83227/verreauxs_sifaka_-_feeding_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83228/verreauxs_sifaka_-_chest_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83229/verreauxs_sifaka_-_hanging_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83230/verreauxs_sifaka_-_resting_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83231/verreauxs_sifaka_-_resting_2_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83232/verreauxs_sifaka_-_hiding_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83233/verreauxs_sifaka_-_habitat_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83235/verreauxs_sifaka_-_frontal_kirindy_reserve_madagascar.html
 Africa,Geotagged,Kirindy Reserve,Madagascar,Madagascar 2019,Propithecus verreauxi,Verreauxs sifaka,Winter,World

Status

Currently this species is considered to be Vulnerable by the IUCN.
In the small spiny forest fragments of South Madagascar, sifaka abundance appears to be influenced by the proportion of large trees and by the abundance of the plant species ''Allouadia procera'', a key species of the spiny forest habitat.
Verreaux's sifaka - closeup 2, Kirindy Reserve, Madagascar A few shots of the largest lemur species to be found in Kirindy Reserve, the Verreaux's sifaka. There are 9 species of Sifaka's (which are named after their call) in Madagascar, here's a useful map showing the distribution of them all:
https://commons.wikimedia.org/wiki/File:Propithecus_species_IUCN_range_map.svg

All species of Sifaka and threatened, mostly by habitat loss due to slash and burn agriculture. It's main natural enemy is the Fossa. 

In behavior, by day this is a slow, inactive herbivore. Their life consists of lazily sitting in trees whilst slowly chewing leafs, after which they take a giant rest from that effort.

One thing they are known for is their weird locomotion at ground level where due to their feet being optimized for life in the trees, they can't really walk or run, instead they hop sideways:
https://www.youtube.com/watch?v=8RiZElNNpAY
https://www.jungledragon.com/image/83136/verreauxs_sifaka_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83132/verreauxs_sifaka_-_wide_eyes_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83135/verreauxs_sifaka_-_closeup_1_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83134/verreauxs_sifaka_-_closeup_3_kirindy_reserve_madagascar.html Africa,Geotagged,Kirindy Reserve,Madagascar,Madagascar 2019,Propithecus verreauxi,Verreauxs sifaka,Winter,World

Behavior

Verreaux's sifaka are diurnal and arboreal, and engage in sunbathing with outstretched arms and legs. Verreaux's sifaka move through the trees by clinging and leaping between vertical supports. They are capable of making remarkable leaps through the trees - distances of 9-10m are not uncommon. On the ground, they hop bipedally.
They live in family groups, or troops, of 2-12, which may consist of one male and female, or many males and females together. Group and population sex ratio can be more or less skewed toward males. Many groups seem to be effectively harem groups with a single dominant male unrelated with resident female. They have a home range of 2.8.5ha, and although they are territorial, it is the food source they will defend rather than the territory's boundaries, as often boundaries overlap. Females are dominant over males, forming a matriarchal society.

Females use anogenital secretion mainly for territory demarcation whereas males seem to use specialized secretions more for sexual "advertisement" than for territorial purposes. Males show bimorphism, by showing either a clean or stained chest, derived from throat gland secretions and smeared on surfaces by rubbing the upper part of the chest. Stain-chested males engage in the most active marking, and chest staining seems to be related to testosterone levels.

Males and females were found to engage in a biological market, exchanging grooming for grooming during the non-mating period, and grooming for reproductive opportunities during the mating period. A study found that females copulate more with stained-chested than with clean-chested males. On the other hand, clean-chested males, with a lower scent-releasing potential, usually offer more grooming to females. This “grooming for sex” tactic allows males with a clean chest to get to copulate with females, even if at low rate.
It has also been discovered that sifaka dyads often engage in post-conflict reunions after aggressive episodes: reconciliation occurs more frequently when food is not involved and for low intensity aggressions. In this species play behavior persists into adulthood where it is used, especially by stranger males during the mating period, as an ice-breaking mechanism to reduce xenophobia
Verreaux's sifaka - resting 2, Kirindy Reserve, Madagascar Another series of this friendly tree grazer, the Verreauxs sifaka. This time I dug up some info on their social system.

Like many lemur species, they live in a female dominant society, where females vastly outnumber males. Typically, in a full group there may be up to 7 females, 3 males, and a few young. One theory for this female dominance is based on the lack of sexual dimorphism. Males and females are roughly of equal size, weight and strength, therefore dominance is based on reproductive value, not physical strength.

However, there is still a dominant male. Out of the 3 males, one will be dominant and will have exclusive mating rights with all adult females in the group. The dominant male can be recognized by its dark patch on the chest. Not to be confused by simply having a dark chest, as this is not a patch, it is  simply their dark skin shining through the fur. 

The other males are called "clean-chested". Groups are usually peaceful where everybody knows their place, except for during the breeding season, where the dominant male may be challenged.
https://www.jungledragon.com/image/83227/verreauxs_sifaka_-_feeding_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83228/verreauxs_sifaka_-_chest_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83229/verreauxs_sifaka_-_hanging_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83230/verreauxs_sifaka_-_resting_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83232/verreauxs_sifaka_-_hiding_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83233/verreauxs_sifaka_-_habitat_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83234/verreauxs_sifaka_-_siesta_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83235/verreauxs_sifaka_-_frontal_kirindy_reserve_madagascar.html
 Africa,Geotagged,Kirindy Reserve,Madagascar,Madagascar 2019,Propithecus verreauxi,Verreauxs sifaka,Winter,World

Habitat

Currently this species is considered to be Vulnerable by the IUCN.
In the small spiny forest fragments of South Madagascar, sifaka abundance appears to be influenced by the proportion of large trees and by the abundance of the plant species ''Allouadia procera'', a key species of the spiny forest habitat.
Verreaux's sifaka - full body, Kirindy Reserve, Madagascar A spectacular action moment of a Verreaux's Sifaka chewing a leaf. Amazingly, this animal manages to upkeep this pace for most of the day, in between its 3 hour breaks.
https://www.jungledragon.com/image/83138/verreauxs_sifaka_-_chewing_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83137/verreauxs_sifaka_-_face_kirindy_reserve_madagascar.html Africa,Geotagged,Kirindy Reserve,Madagascar,Madagascar 2019,Propithecus verreauxi,Verreauxs sifaka,Winter,World

Reproduction

Females give birth to one infant after a gestation period of 130 days, between June and August. For the first 6–8 weeks, the infant clings to the mother's stomach, but for the following 19 weeks, it clings to her back.
Verreaux's sifaka - chest, Kirindy Reserve, Madagascar Another series of this friendly tree grazer, the Verreauxs sifaka. This time I dug up some info on their social system.

Like many lemur species, they live in a female dominant society, where females vastly outnumber males. Typically, in a full group there may be up to 7 females, 3 males, and a few young. One theory for this female dominance is based on the lack of sexual dimorphism. Males and females are roughly of equal size, weight and strength, therefore dominance is based on reproductive value, not physical strength.

However, there is still a dominant male. Out of the 3 males, one will be dominant and will have exclusive mating rights with all adult females in the group. The dominant male can be recognized by its dark patch on the chest. Not to be confused by simply having a dark chest, as this is not a patch, it is  simply their dark skin shining through the fur. 

The other males are called "clean-chested". Groups are usually peaceful where everybody knows their place, except for during the breeding season, where the dominant male may be challenged.
https://www.jungledragon.com/image/83227/verreauxs_sifaka_-_feeding_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83229/verreauxs_sifaka_-_hanging_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83230/verreauxs_sifaka_-_resting_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83231/verreauxs_sifaka_-_resting_2_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83232/verreauxs_sifaka_-_hiding_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83233/verreauxs_sifaka_-_habitat_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83234/verreauxs_sifaka_-_siesta_kirindy_reserve_madagascar.html
https://www.jungledragon.com/image/83235/verreauxs_sifaka_-_frontal_kirindy_reserve_madagascar.html
 Africa,Geotagged,Kirindy Reserve,Madagascar,Madagascar 2019,Propithecus verreauxi,Verreauxs sifaka,Winter,World

Food

Verreaux's sifaka forage for food in the troop it lives in, primarily in the morning and late afternoon, so they can rest during the hottest part of the day. They are herbivores; leaves, fruit, bark and flowers are typical components of the diet. However, they are mostly folivorous and they seem to choose food items based on quality rather than on availability.

References:

Some text fragments are auto parsed from Wikipedia.

Status: Vulnerable | Trend: Unknown
EX EW CR EN VU NT LC
Taxonomy
KingdomAnimalia
DivisionChordata
ClassMammalia
OrderPrimates
FamilyIndriidae
GenusPropithecus
SpeciesP. verreauxi
Photographed in
Madagascar