White-nosed Coati taken in Costa Rica

Throughout the rainforests, mountaintops, and deserts of South and Central America, Mexico, and the Southern United States roam a peculiar mesocarnivore that is losing habitat quickly.  Despite the adaptability and ecological importance of this New World mammal, land clearing, and forest fragmentation are squeezing some of their populations toward extinction.  These relatives of the raccoon and ringtail hold an important niche in their habitats yet remain misunderstood and unprotected in most of their range.

Coatis have a narrow head, slender body, and short, powerful legs.  Most are dark brown to black, with their underside being lighter shades.  Some coati species have pronounced white rings encircling their tails, while the rings are less obvious in others.  Being members of the Procyonidae (Raccoon) Family, coatis are divided into two genera with two species representing each genus.  The two most populous species, the white-nosed (Nasua narica) and South American (Nasua nasua) coati are similar in size, with the females measuring approximately 12-16 inches long while the males reach up to 24 inches.  Weights can range from six to twenty pounds.  The tails of both species are long, about the same length as their body, and covered in fur.  The white-nosed species achieves its name from the white patch on the rostrum surrounding the nose.

The two mountain-dwelling species, the western (Nasuella olivacea) and eastern (Nasuella meridensis) mountain coatis are both significantly smaller in size and lighter in weight, plus the olivacea species has a shortened tail and a dark stripe extending down the spine.  Although not prehensile (able to grip), coatis use their tails for balance and communication.  Their legs are built for both digging up food and climbing trees, with strong sedentary claws and ankles that can rotate 180 degrees, which allows them to climb down trees headfirst.  The unique snouts of coatis are greatly elongated and upturned.  The flexible nose roots along the ground surface like swine when in search of food, earning them an unofficial nickname of “hog-nosed raccoon”.

The white-nosed coati inhabits the most Northern range, existing from Northern Columbia to Southern Arizona and New Mexico, encompassing all of Central America and Mexico.  While the South American coati occupies most of the continent, spanning across the tropical rainforests of Southern Venezuela and Columbia Southward to Northern Argentina.  Preferring the wet lowlands, this species avoids the high-elevation Andes Mountains.  However, the western mountain coati is well adapted to the cloud forests of the high Andes in Ecuador and Western Columbia.  Finally, the eastern mountain coati is relegated to a small zone of the Andes Mountains above 7,000 ft in Northwestern Argentina.

Coati habitat varies greatly according to each species, mostly due to elevation differences.  The white-nosed and South American coatis typically prefer lowland rainforests or grasslands of the Amazon ecosystem, while the mountain coatis live in colder high-elevation cloud forests.  Some white-nosed coati populations have adapted to the arid deserts of Arizona and New Mexico; however, they tend to live in wooded mountain forests and avoid the hot desert floor.

For most of the year, adult female and male coatis live separately.  Females and juveniles gather into groups, known as troops, of up to 30-40 individuals that travel together in search of food. Males have solitary lives until breeding season, which coincides with the wet season. The seasonal rains promote fruit growth, therefore allowing ample nourishment for the young after weaning.  Coatis are polygynous, so during breeding season one male is permitted to enter the troop and mate with as many receptive females as possible.

Pregnant females then leave the troop temporarily to create a birthing nest that accommodates their offspring.  She builds a makeshift structure of branches, leaves, and other forest debris within the limbs of a sturdy, tall tree.  Some mothers-to-be prefer a rock crevice to provide safety for their young.  Three to seven kits are then born after a gestation of around eleven weeks.  The youngsters solely depend on their mother for the first six weeks, after which the new mom and her kits rejoin the troop.

Unrelated female coatis are known to watch over the offspring of other mothers.  These babysitters assist in the rearing of the new kits by providing protection and guidance while their mother is busy finding food.  Young female coatis reach maturity at two years but remain with the troop.  Males reach maturity around three years old, then leave the troop for a solitary life until the following breeding season.  In the wild, coatis can live up to seven years, however, in captivity, some individuals have lived as long as fourteen years.

Coatis constantly scour across the forest floor in search of anything edible.  As with all mesocarnivores, they are omnivorous and eat a wide range of plant material, live prey, and carrion.  Coatis resemble the food-searching behavior of hogs, as they use their long flexible nose and five-fingered paws to push leaves and rocks aside while sniffing out fruit or invertebrates hiding under the ground litter.   Their acute nose can detect underground quarry, then they use their sturdy claws to dig up the item.

Spiders comprise a portion of their diet, even hunting down tarantulas to feast upon.  Like raccoons washing their food, coatis roll the tarantulas around on the ground removing the irritating hairs of the large spiders before consuming.  When an opportunity arises, coatis also catch small rodents, birds, and lizards, or raid nests for eggs.  Cacti are another favorite delicacy, and troops are known to revisit the same cactus for a nibble over and over.

Cooperative foraging exists among troops, where one adult will shake a tree while the remainder of the troop collects the fallen fruit below.  Ecologists believe coatis’ feeding behaviors promote aeration of the soil by overturning the top layer.  This process recycles nutrients back into the soil, promoting new plant growth.  Additionally, studies have shown coatis disperse seeds over long ranges through their scat.

Researchers are currently studying a possible dependent relationship that many flowering plants have with coati being a primary pollinator of their species.  Finally, coatis are an important food source for predators such as puma, maned wolves, tayras, jaguars, large snakes, and numerous raptors.  The ecological importance of coati species is vast and seems to be growing as more research is conducted.

Unlike other procyonids, coatis are diurnal, spending most of the daytime on the ground foraging, then climbing trees to sleep among the canopy at night.  Not only are coatis excellent climbers, but are good swimmers, too.  Individuals are highly communicative, often grunting, snorting, and whining as they travel together.  When a predator is detected, the entire troop climbs trees and emits clicks and barks to alert others.  Posturing displays are also common to maintain order within the troop.  For example, subordinate members cover their noses with their front paws to exhibit submission, while grooming promotes social bonding.

When traveling, all coatis hold their tail upright, a behavior believed to assist in the location of individuals while in tall grass.  Biologists believe coatis can recognize one another by sight, voice, and scent.  To assist with olfactory recognition, coatis have scent glands on their abdomen and neck that emit a unique odor for each individual.  Males utilize this scent to mark territory and ward off breeding competitors.  Studies in Panama even indicate coatis there are intentionally smearing resin from torchwood trees upon one another as a potential method of scent marking, or perhaps to ward off insects.

Since coatis live in dense lowland jungles and high-elevation forests, most humans never encounter them in the wild.  However, human impacts upon their habitat are being felt by coati populations across their range.  Rainforest deforestation is a major contributor to coati decline, while agriculture practices fragment their habitat.  All four species of coati are declining in numbers, but the mountain coati populations are particularly in grave danger.  The IUCN lists the western mountain coati as Near Threatened, while the eastern species is already considered Endangered.

Additionally, coatis are occasionally mistakenly killed by hunters seeking other game species.  Some indigenous communities still eat coati, which limits certain local populations.  Throughout South America and Mexico, the hunting of coati remains unregulated.  Even Arizona considers them vermin and there is no control over their taking.  Thankfully, New Mexico considers them Endangered according to state law.  Although coatis reportedly can make a suitable household pet, removing wild coatis to sell them has placed increased pressure on population numbers.

Coatis hold an important mesocarnivore niche in the Americas.  By controlling rodent, invertebrate, and small reptile populations, coatis prevent the overpopulation of nuisance species, while at the same time providing an important food source for larger predators.  The ground disturbance caused by coati during foraging is a known benefactor to nutrient absorption, plus the dispersal of seeds and pollen are obvious contributions to ecosystem health.  Despite all these benefits, humans continue to deplete coati numbers both directly through hunting or pet trade and indirectly through habitat degradation.  More emphasis must be placed on researching these fascinating mesocarnivores to determine exact population counts and how to best preserve both their numbers and habitat before risking their disappearance.

Jeremy Heft
WERC Biologist, Educator, & Sanctuary Consultant