Golden Crowned Sifaka, Propithecus tattersalli
The golden-crowned sifaka (Propithecus tattersalli), also known as Tattersall’s sifaka, can only be found on the island of Madagascar. Within its range, it is known by natives as ankomba malandy, or akomba malandy, which means “white lemur”. Its range is small, comprising only 44 fragmented forest areas that surround the town of Daraina. The borders of this range include the Manambato River and the Loky River. Studies show that the 44 areas total only 170 square miles. This sifaka can be found living at elevations of up to 1,600 feet, though it tends to choose lower areas. Within these altitudes, it lives in arid deciduous, gallery, or semi-evergreen forests.
Originally discovered by Ian Tattersall in 1974, the golden-crowned sifaka was not formally described until 1988. Tattersall was not confident in assigning the lemur into its own species, and so placed it as a color variant of the silky sifaka in his 1982 book, The Primates of Madagascar. He described its nearly all white coat, but noted the patch of orange fur surrounding its face, and tufted ears that are not found on the silky sifaka or any other species of lemur.
In 1986, Elwyn Simmons and a research team from the Duke Lemur Center conducted a live capturing of golden-crowned sifaka individuals for breeding purposes, after learning that the forest in which Tattersall first spotted the sifaka was doomed to be cut down for charcoal production. They studied the creatures, captured and areas from 3.7 to 4.3 miles northeast of Daraina, and named them after Tattersall.
Despite the golden-crowned sifaka receiving its own species name within a genus, there are conflicting results from experts who study it. In 1988, when Simmons and his research team studied vocalizations, karyotypes, and size, they found the golden-crowned sifaka to be more closely related to western forest sifakas in the P. verreauxi group in size, but favored eastern forest sifakas in the P. diadema group genetically. Despite these similarities, the golden-crowed sifaka received its own species classification due to its uniquely tufted ears and environmental isolation.
Genetic testing conducted in 1997 further proved the classification of the golden-crowned sifaka. However, in more recent years, genetic studies have produced results that suggest that it is not its own species, but a subspecies in the P. verreauxi group. In 2001, it was found that the golden-crowned sifaka was a deviation from Coquerel’s sifaka, which was classified in the P. verreauxi group at that time. This would mean that it was merely a subgroup, along with Coqurerl’s sifaka, within the P. verreauxi group if proved true. In 2004, further genetic testing suggested that although it was separate from two other types of sifaka groups, it was still closely related enough to be considered part of the P. verreauxi group.
The golden-crowned sifaka can weigh between an average of 7.5 and 7.9 pounds, making it one of the smallest of sifakas. It can reach a total body length of 37 inches, of which the tail can comprise up to 19 inches. It soft fur is typically creamy white in color, with hints of gold, brown, or black on the neck. Pale orange fur can be seen on the top portions of the limbs as well as white fur on the rest of the hind legs and tail. The top of the head holds the characteristic golden or orange “crown” and the ears are distinctively tufted with long white fur. As is typical for sifakas, the eyes are orange in color and the face is hairless and black. It has a broad nose that sometimes holds a patch of white fur, which helps to distinguish it from other sifakas.
Like other sifakas, the golden-crowned sifaka is mainly diurnal, or active during the day, although studies have shown that it may be crepuscular, being active in the early mornings and evenings during the rainy months of November to April. It has even been spotted eating during the nighttime in captivity. In the wild it can traverse a distance of 1,515 to 3,530 feet while searching for food. It sleeps within the emergent layers of trees during the night. It emits many calls, including a grunt followed by quick, repeated “churr” noises when stressed. If an aerial threat has been spotted, the golden-crowned sifaka will commence with a mobbing call, “ganging” up on the threat to scare it away. When a terrestrial predator has been spotted, the sifaka will release a characteristic “shē-fäk” that sounds similar to the alarm call of Verreaux’s sifaka.
The golden-crowned sifaka lives within social structures that are similar to other lemurs, in groups of up to six individuals on average. However, the ratio of males to females is more balanced and each group will typically contain two or more individuals of the same sex. Females take precedence over males, and only one is able to mate successfully in a year, causing most males to shift between groups during the mating season.
The home ranges of groups of golden-crowned sifakas are small. One study found that the range was between 0.069 and 0.11 square miles, and another found that it was between 0.035 to 0.046 square miles, only slightly larger. Because these ranges are so small, many groups will cross paths. It is thought that members of different groups are very aggressive towards each other, although physical harm rarely occurs. Members of the same sex are more likely to argue, and most sifakas will emit a growl or grunt-like vocalization that displays annoyance. Scent marking is the most common way for groups to defend themselves, and both males and females will mark trees within their home range using scent glands located on the genitals, although males have an extra scent gland to use located on their chest.
The golden-crowned sifaka will typically mate during the last week of January, giving birth to one baby sifaka once every two years. The baby will latch onto the mother’s tummy until it is able to move onto the back, after which the mother will only tolerate carrying her young for a short time. Typically, babies will reach 70 percent of their full adult size at one year of age, and when sexually mature will leave their birth group to join a different group. Studies and reports have shown that these sifakas are not afraid to leap across distances of up to 660 feet of empty grassland in order to join a group, suggesting that fragmented forests do not affect the species like other lemurs. Mating, birth, and weaning may vary upon location, as dissimilar areas are affected by the seasons differently. It is thought that this occurs because optimum vegetation is pertinent to both mother and young to flourish.
The diet of the golden-crowned sifaka is thought to contain up to eighty species of plants, which are eaten when available. Seed consumption does not depend on season, and so these sifakas will eat them year-round. Unripe flowers, fruits, and leaves make up a large portion of the diet as well. During the dry season, some individuals can be seen eating tree bark. Studies have shown that diet can vary form group to group, depending on the location, and so certain groups will eat more of a certain type of plant. It is thought this occurs to ward off negative effects from particular plant toxins.
Although the golden-crowned sifaka has alarm calls for both aerial and terrestrial threats, the only known predator to hunt it is the fossa, a cat-like creature that is native to Madagascar. This sifaka is susceptible to infection caused by a microfilarial parasite that may be an unknown species of nematode within the genus Mansonella. A study, which produced these results, also showed that otherwise, healthy individuals were not adversely harmed by the parasite, but the extent of its damage on a population is unknown. The study also found that none of the golden-crowned sifakas considered had intestinal parasites or malaria, though 48 percent did have visible ear mites.
Humans have played a large role in the decline of many lemur populations, including the golden-crowned sifaka. It was estimated that by 1985, 34 percent of the eastern rainforest had vanished, and if this rate of deforestation continued, there could easily be no forest left by 2020. Human actions including gold mining, illegal logging, slash and burn agriculture, and poaching have all greatly decreased the golden-crowned sifaka’s suitable habitat areas and populations.
Malagasy farmers will use fires, called slash and burn agriculture, to promote healthy grass growth, but these fires prevent the forest from returning and they even spread to forest edges, destroying more vegetation and ecology than was intended. These fires, known as tavy, increase the rate at which the sensitive soil must be rotated, causing a growth in expansion necessity as well.
Even though the Malagasy people prefer coal for cooking energy, it has become more common to use wood, or kitay. This timber is also being used for building houses, and because all of the dead wood within the forests has been removed, humans are beginning to cut down fledgling, healthy trees for fuel and materials, and this occurs commonly in areas surrounding villages. Although fragmented forest’s shapes and sizes were thought to have remained unchanging for fifty years, a study conducted in 2002 showed that five percent of the smallest areas had completely vanished only six years before because of human activities.
Gold mining has become an increasing threat to the golden-crowned sifaka within their habitats. Although the operations are small, the miners will hunt the sifaka, as well as destroy trees that they require for food and shelter by digging large pits, decimating the root systems of the forest trees. Although the golden-crowned sifaka is protected by the local fady, or taboo, that associates the lemurs with humans and prevents them from being eaten, gold miners from different areas do not adhere to the laws, and hunt them for bushmeat. Because the sifaka are so easily found and are not afraid of humans, David M. Meyers estimated in 1933 that if the bushmeat hunting increased, populations of golden-crowned sifaka would be decimated. Indeed, it has increased, and one isolated population near Ambilobe is already extinct.
In 2009, a political crisis swept through Madagascar, causing poachers to increase their hunting of the golden-crowned sifaka in the Daraina area. These poachers sold the meat to restaurants, where it is considered a delicacy. Photographs of dead lemurs that had been smoked for transport were taken by Fanamby and released by Conservation International in August of 2009. Shortly after the pictures were released, fifteen people were arrested for selling the endangered lemurs. These lemurs were purchased for 1,000 ariary, around US$0.53, and sold in restaurants for 8,000 ariary, or US$4.20. According to Russell Mittermeier, the president of Conservation International, these arrests are not effective in decreasing the hunting of the lemurs, as those arrested will just receive a “slap on the wrist”.
Due to the golden-crowned sifaka’s preference for large forest habitats, it has been assumed that the lemur is sensitive to forest fragmentation. However, it is not inhibited by humans and occurs within areas where gold mining is conducted. Despite its tolerance to human activities, it still has low population numbers, small ranges, and highly fragmented habitats. Because of this, the outlook for survival for the golden-crowned sifaka is grim.
As of 2002, it was estimated that the population of these sifakas ranged between 6,120 and 10,080 individuals, of which only 2,520 to 3,960 were capable of reproduction. In 1997, the IUCN placed it on the 25 most endangered primates, and in 1992, the IUCN’s Species Survival Commission Primate Specialist Group had placed it as their utmost priority. In 2008, the conservation status of “Critically Endangered” was re-assessed and the golden-crowned sifaka was given a new status of “Endangered”.
The areas in which the golden-crowned sifakas prefer to live are important to both the lemurs and to humans. Conservation efforts have included these forests, allowing some areas that require little to no protection open to cultivation. Areas that are important to the survival of the golden-crowned sifaka are strictly protected. In 2002, no forest areas where the sifaka resided were located in national parks or reserves, but a study conducted in the same year proposed a network of protected areas including forest fragments near Daraina and north of the Monambato River, as well as fragments located in northern forests. Because of this, Fanamby, a non-governmental organization, and Conservation International created a protected area of 77 square miles that both Fanamby and the Ministry of Water and Forests maintain. Unfortunately, it was found that only ten patches of forest that constituted viable lemur habitat remained as of 2008.
As is common for endangered species, captive breeding was attempted within a small group of golden-crowned sifakas. In 1987, during the same expedition that resulted in the classification of this sifaka, the Duke Lemur Center (DLC) of Durham, North Carolina acquired permission from the Madagascar government to attain and export a few individuals. During this time, plans were made to launch a breeding population at Parc Ivoloina, formerly known as Ivoloina Forestry Station as well.
Two female and two males were captured in 1987, and taken back to the DLC. Unfortunately, the group was too small to reproduce effectively, although one individual was born, and the special diet of the golden-crowned sifaka made it difficult to maintain the fragile population. In 2008, the last captive golden-crowned sifaka passed away. Although the only past attempt to breed the lemurs in captivity ultimately failed, DLC asserts that if habitat protection fails, a captive breeding group of golden-crowned sifakas is an important plan to fall back on in order to bolster their population numbers.
Image Caption: Golden-crowned Sifaka (Propithecus tattersalli). Credit: Jeff Gibbs/Wikipedia(CC BY-SA 3.0)