Mongooses and Fossa: Herpestidae

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MONGOOSES AND FOSSA: Herpestidae

RING-TAILED MONGOOSE (Galidia elegans;): SPECIES ACCOUNTS
FOSSA (Cryptoprocta ferox): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

Mongooses are a family, Herpestidae, of small to medium-sized, mainly carnivorous Old World mammals. Their overall appearance suggests a small, generalized mammalian carnivore. They have long bodies, short but powerful legs, and long, often bushy tails. In some ways, they converge with (resemble) the mustelids (mammal family Mustelidae: weasels, badgers, skunks, otters, wolverines) of the New World.

Family Herpestidae, including species in Madagascar, includes about thirty-five species and seventeen genera (JEN-uh-ruh), although not all taxonomists, or classifiers of animal types, agree as to the exact number of genera and species. The large island of Madagascar, off the southeast coast of Africa, has eight mongoose species arranged in four genera, probably all descended from a single founder species that rafted on floating vegetation from Africa. The Malagasy mongooses are classified in a subfamily of their own, the Galidiinae. All other mongoose species are classified within subfamily Herpestinae.

Adult head-and-body length throughout family Herpestidae runs 9 to 25.5 inches (23 to 65 centimeters), tail length 9 to 20 inches (23 to 51 centimeters), and weight just under 1 pound to 9 pounds (0.4 to 4.0 kilograms). The exception to these measurements is the fossa of Madagascar, the largest of the Herpestidae and the most un-mongoose-like of all mongoose species. A fossa can grow up to 31.5 inches (80 centimeters) head-and-body length, with a tail just as long, and an adult weight of 20 pounds (9.1 kilograms).

Fur colors in herpestids are various shades of brown and gray, with lighter, sometimes white, fur on the underside. Some species carry stripes or stipplings on their darker fur. The fur can vary in texture as well, from soft to coarse, short to long. There are five clawed digits on each of the four paws, the claws of the forefeet long, sharp, and curved. Except for the fossa, the claws are not retractable, meaning they cannot pull them back into the paw. The small head and face taper to a pointed muzzle, sometimes with a straight bridge from crown to the end of the snout, or there may be a distinct, sloped forehead where the head and muzzle join. The ears are short and rounded.

Herpestids carry glands for scent-marking in their cheeks and near their anuses. Some species can shoot out a foul-smelling fluid from the anal glands.

GEOGRAPHIC RANGE

Mongooses live in mainland Africa, southern Europe, Madagascar, southern Asia including India, the Malay Peninsula as far as and including Sumatra, Borneo and Java; also the islands of Hainan and Taiwan.

HABITAT

Mongooses live in various types of forest, including humid tropical rainforest, also dry grasslands and near-desert. They shelter in self-made burrows in the ground or in termite mounds, or in natural shelters like hollow logs and spaces within rock piles.

MONGOOSES AND HORNBILLS GETTING ALONG

The dwarf mongoose has a mutually beneficial relationship with two bird species, the red-billed hornbill and the eastern yellow-billed hornbill. In the scrub country of eastern Kenya, the mongoose and either of the hornbill species forage together, eating the same prey, the hornbills keeping their senses alert for the presence of threat animals, especially birds of prey. The companionship allows the mongooses to forage in peace, while the birds benefit from creatures flushed out by the mongooses. The hornbills sound off with warning calls when a predator approaches, even warning at the sight of predators of mongooses that are not enemies of hornbills.

DIET

Mongoose species have generalized, mainly carnivorous diets, helping themselves to insects, crabs, millipedes, earthworms, reptiles, amphibians, mammals, birds, birds' eggs, fruits, and roots. Before eating toads or caterpillars, a mongoose will roll them back and forth on the ground to wipe off skin poisons of toads and irritating hairs of caterpillars. Among mongoose species that eat bird eggs, a mongoose will break open an individual egg by holding it in its forepaws and pitching it backward between its hindlimbs and into a rock, or by standing up on its hind legs and dropping the egg. Several species eat fruit as supplements to a mainly meat diet. Some species swim in ponds and streams, searching for fish and other aquatic animals.

An individual mongoose baits a snake by skillfully avoiding and dodging the reptile's lunges until it tires and slows down in its actions, enabling the mongoose to dart in and seize the snake behind its head, killing it by biting, then eating the snake at leisure. Mongooses are not immune to the venom, so that a mongoose-on-snake tussle is always dangerous and can end in death for either party.

BEHAVIOR AND REPRODUCTION

Mongooses are energetic, aggressive, and playful. They may hunt and forage alone or in groups. Some species are nocturnal, active at night, others are diurnal, active during the day. Diurnal species often start their days by sunning, outstretched on rocks or the ground near their shelters, and exercising to limber themselves up for a day of foraging.

Mongooses live in colonies of up to fifty individuals. These may live in burrow networks or just build temporary shelters for themselves during migratory foraging.

Some mongoose species breed seasonally, others breed throughout the year, females giving birth two or three times annually. Gestation periods range from forty-two to eighty-four days. There are one to four young per litter. Captive Egyptian mongooses have lived for over twenty years.

MONGOOSES AND PEOPLE

Mongooses and humanity share intertwined histories. The animals have been the source of innumerable folk tales in their native lands, e.g., "Rikki-tikki-tavi," the famous short story by British writer Rudyard Kipling, based on native legends of India. Mongooses have been praised for destroying pests and condemned for preying on non-pests, especially domestic poultry.

From ancient times until the present, mongooses have been introduced by humanity to mainlands and islands over much of the world, in attempts to keep down problem populations of rats and snakes: Italy, Spain, Portugal, Yugoslavia, many of the Caribbean islands, and the islands of Hawaii and Fiji. Since mongooses are so highly adaptable, they soon outdo the original problem they were introduced to control by becoming pests themselves, preying on harmless and beneficial local bird and mammal species, and raiding poultry. A number of countries that have learned the lesson the hard way and now outlaw the possession or importation of mongooses.

CONSERVATION STATUS

The World Conservation Union (IUCN), includes on its Red List of Threatened Species, four mongoose species considered Vulnerable, facing a high risk of extinction, and five Endangered, facing a very high risk of extinction. Three Vulnerable and three Endangered species are in Madagascar. The main threats to mongoose species are habitat destruction, and, on Madagascar, habitat loss plus competition and predation by introduced predators like dogs and cats. Nevertheless, family Herpestidae, overall, is flourishing.

RING-TAILED MONGOOSE (Galidia elegans;): SPECIES ACCOUNTS

Physical characteristics: In appearance, the ring-tailed mongoose more or less follows the general mongoose body plan, while being a particularly beautiful and striking species, with red-brown to dark brown body fur and a long, bushy tail striped alternately with broad, red-brown and black rings. The underside is very dark to black. The head-and-body length of an adult Malagasy ring-tailed mongoose runs 12.5 to 14 inches (32 to 36 centimeters), tail length, 10.5 to 12.5 inches (27 to 32 centimeters), and body weight of 1.5 to 2.2 pounds (0.7 to 1 kilograms).


Geographic range: This mongoose lives in eastern and western Madagascar.

Habitat: The ring-tailed mongoose inhabits humid tropical rainforest along Madagascar's east and northwestern coasts, and drier, seasonal forest along much of the west coast.


Diet: Ring-tailed mongooses feed on small mammals, birds, birds' eggs, frogs, fish, reptiles, insects, and fruits. They also prey on two small primate species native to Madagascar, the greater dwarf lemur, and the brown mouse lemur.


Behavior and reproduction: Ring-tailed mongooses mate from April to November, and a single young is born from July to February. The gestation period runs seventy-nine to ninety-two days. The young is sexually mature at two years of age. A captive ring-tailed mongoose lived for over thirteen years.

Malagasy ring-tailed mongooses forage and hunt during daylight. They can swim and climb trees easily but do most foraging on the ground. These mongooses forage and hunt in groups of up to five, each group made up of a mated pair and offspring. As they wander, the mongooses mark trees and rocks of their territory with anal scent glands. They shelter in burrows during nights.

The ring-tailed mongoose and people: This animal seems to have little fear of humanity other than natural caution, and will investigate native villages and biological research camps, stealing whatever human garbage or food they can lay hands on. They may add domestic poultry to their diets, resulting in people hunting and harrassing them.


Conservation status: This mongoose is listed as Vulnerable by the IUCN. Some naturalists, after very recent surveys of the species in Madagascar, consider it of little or no conservation concern because of its high numbers and adaptability. ∎

FOSSA (Cryptoprocta ferox): SPECIES ACCOUNTS

Physical characteristics: Its name derived from a native Malagasy word, and pronounced "foosh," this puzzling animal is as worthy of biodiversity poster status as the more famous lemurs of Madagascar.

The fossa is the largest of all mongoose species, with an adult head-and-body length of 24 to 31.5 inches (61 to 80 centimeters), a tail as long as the head and body, and an adult weight of eleven to twenty pounds (5 to 10 kilograms). A fossa looks like a combination of dog, cat, and mongoose, and has retractable claws, like a cat's, something not seen in other mongoose species. If approaching head-on, a fossa gives the impression of a scaled-down puma, but a side view shows the snout to be longer than that of the true cats, but shorter and wider than the norm among mongoose species. The gray-brown nostril pad is furless and prominent, like a dog's. The overall appearance and behavior suggests a cat rather than a dog.

The body is long and sleek and the legs are short but powerful, as in a mongoose. The coat color is rich reddish-brown, the undersides lighter but stained with an orange secretion from skin glands. This secretion is more abundant in males than in females. There are five padded digits on each of the four feet. Though its movements are often considered plantigrade, meaning that the entire foot, from the toetips to the back of the heel, touch the ground when walking, fossas have also been seen to walk digitigrade, that is, only on the toetips. The large, prominent eyes are brown and lustrous, and have pupils that can retract to vertical slits, as in cats. The ears are large, prominent, and narrower than in typical mongoose species.

The fossa was originally classified as a direct descendant, little changed, of the ancestor species that gave rise to cats (Felidae) and dogs (Canidae). That classification arose from both to the appearance of the fossa and to the notion that Madagascar was a natural refuge for primitive mammal species driven to extinction elsewhere by more advanced species. At the same time, the fossa is the living creature closest in form to the dog-cat ancestor. Its classification is still uncertain. Genetic comparison studies strongly support the fossa and the other Malgasy mammal carnivores as being descendants, having changed forms over the ages through adaptive evolution, of a single colonizing species of mongoose. The founder species must have floated from Africa to Madagascar twenty to thirty million years ago. The fossa is the end result of adaptive evolution by which a mongoose, over countless generations, became something like a cat. At the same time, the fossa keeps a number of mongoose-like features. Scientists have found remains of a larger species related to the fossa, since named Cryptoprocta spelea.


Geographic range: Fossas live in all of the forested areas of Madagascar.


Habitat: Fossas live in the humid tropical rainforests of Madagascar's east coast and the drier forests along its western coast.


Diet: The fossa is carnivorous and able to deal with nearly all sorts of small to large prey animals on Madagascar, including the larger lemur species, which can be bigger than house cats. Fossas also prey upon snakes, tenrecs (native insectivorous mammals of Madagascar), and rodents, most often introduced rats. Fossas only rarely feed on insects and other invertebrates.


Behavior and reproduction: Fossas hunt at any time of night or day. They can swim and are adept at climbing and jumping among trees while chasing prey. The animals can turn their ankles so that their hindfeet face rearward, a unique adaptation that aids them in keeping a grip on treetrunks. The long tail acts as a balance while the fossa climbs or jumps between trees. Fossas hunt alone, or in family groups made up of a mother and her young.

There is a single annual mating season from October into December. Gestation lasts six to seven weeks. Litters number two to four young. Fossa young are very cute and endearing. They have big ears and eyes, their faces suggest a combination of domestic kitten, puppy, and lion cub, and they stare out at the world with the intent, slightly bewildered stare of young domestic kittens.

Mating is a complex affair, resembling that of cats. A female in heat stations herself in a tree, while several males, following her scent, gather around the tree, vocalizing and fighting among themselves. Then, one at a time, the males climb the tree and are accepted or rejected by the female. If she accepts a male, she will usually walk farther out on a branch but allow the male to mount her from behind, his forepaws resting on her neck, while he gently grips the female's nape in his jaws. A single mating can last for several hours, and the female will mate with several of the gathered males.

Only the mother raises the young, in a tree hollow or a hollowed-out termite nest. The young of both sexes reach sexual maturity at four years. A most interesting phenomenon among female fossa young is that they pass through a brief pseudo-masculine stage in their second year, during times of becoming less dependent on the mother and reaching sexual maturity. Their genitals come to resemble those of an adult male, they leave ano-genital scent markings on objects, as do adult males (adult females do not, except in mating season), and the female young secrete more of the fur-staining orange fluid than do adult females. Why this occurs is unanswered, and the young females lose the masculine characteristics as they approach sexual maturity.

Fossas have been known to live for twenty years in captivity.


Fossas and people: The fossa has not fared well with humans in Madagascar. Fossas raid chicken coops, leaving resentment behind, and an aura of superstitious fear surrounds them.


Conservation status: The fossa is listed as Endangered by the IUCN. Although widespread throughout Madagascar, the fossa's population density and total population are low, making it especially vulnerable to deforestation, which is ongoing and rampant in Madagascar. ∎

FOR MORE INFORMATION

Books:

Estes, R. The Behavior Guide to African Mammals. Berkeley and Los Angeles: University of California Press, Ltd., 1991.

Garbutt, N. Mammals of Madagascar. New Haven, CT.: Yale University Press, 1991.

Goodman, Steven M., and Jonathan P. Benstead, eds. The Natural History of Madagascar. Chicago and London: University of Chicago Press, 2003.

Jolly, Alison. A World Like Our Own: Man and Nature in Madagascar. New Haven, CT: Yale University Press, 1980.

Periodicals:

Creel, S., Nancy Creel, David E. Wildt, and Steven L. Monfort. "Behavioural and Endocrine Mechanisms of Reproductive Suppression in Serengeti Dwarf Mongooses." Animal Behaviour no. 43 (1992): 231–245.

Creel, S. R., "Inclusive Fitness and Reproductive Strategies in Dwarf Mongooses." Behavioral Ecology no. 5 (1994): 339–348.

Dollar, Luke, "Assessing IUCN Classifications of Poorly-Known Species: Madagascar's Carnivores as a Case Study." Small Carnivore Conservation, the Newsletter and Journal of the IUCN/SSC Mustelid, Viverrid and Procyonid Specialist Group no. 22 (2000): 17–20.

Hawkins, C. E., J. F. Dallas, P. A. Fowler, R. Woodroffe, and P. A. Racey. "Transient Masculinization in the Fossa, Cryptoprocta ferox (Carnivora, Viverridae)." Biology of Reproduction 66, no. 3 (March 2002): 610–615.

Rasa, O. A. E., "Behavioural Parameters of Vigilance in the Dwarf Mongoose: Social Acquisition of a Sex-Biased Role." Behaviour no. 110 (1989): 125–143

Rood, J. P., "Dwarf Mongoose Helpers at the Den." Zeitschrift fur Tierpsychologie no. 48 (1978): 277–287

Rood, J. P., "Mating Relationships and Breeding Suppression in the Dwarf Mongoose." Animal Behavior no. 28 (1980): 143–150.

Yoder, Anne D., et al. "Single Origin of Malagasy Carnivora from an African Ancestor." Nature 421 (2003): 734–737.

Web sites:

"Carnivores of Madagascar." Earthwatch. http://www.earthwatch.org/expeditions/dollar/meetthescientists.html (accessed on July 7, 2004).