Greater Grison

## About

A greater grsion.

The greater grison ***(Galictis vitatta)*** or furão grande in Portuguese, is a species of large mustelid which occurs in South and Central America. It morphologically resembles the distantly related honey badger ***(Mellivora capensis capensis)***, with a long body, stout limbs, black underbelly, grey-white dorsum and visually similar face. The fainter grey-sliver colour, undefined separation between the grey and black fur that additionally covers the flanks and tail as well as the white strip of fur which stretches from the head to the mid point of the neck of the greater grison separates it visually from the honey badger. Another differentiating feature is the grison's head which has a stouter snout and more cat-like face. The greater grison also holds its head higher off the ground than the honey badger, making its neck appear longer and more prominent. They also have round ears and a short brushy tail. In some individuals, the more solid white fur around the face, ears and upper neck is yellow, dull orange or a tan-brown, but is most commonly silver, grey or white. The greater grison can measure up to 45-60cm (18-24in) and can weigh between 1.5-3.8kg (3.3-8.4lbs).

## Diet

The greater grison is a carnivorous hunter, most prolifically targeting mammals, though, dead grisons have been found with birds, reptiles, amphibians and invertebrates in their stomach contents. As an opportunist the greater grison has also been known to eat wild bananas when available, but are primarily carnivorous.

## Conservation Status

The greater grison is considered least concern by the IUCN, and is mostly threatened by anthropogenic factors. Fires and deforestation have displaced grisons however, the species has proven relatively tolerant to these changes. Habitat fragmentation via the construction of roads and the development of similar infrastructure has lead to increased casualties in roadkill incidents.

## Range and Population

The greater grison inhabits a wide range which stretches as far north as the eastern coast of Mexico, through the Yucatan peninsula and all the way down to central Bolivia. Due to its immense range, the greater grison has diversified into four extant separate and distinct subspecies. One additional subspecies; ***(G. v. fossilis)*** is also recognised however, the subspecies went extinct sometime during the Pleistocene. The nominotypical species, ***(G. v. vitatta)***, occurs most frequently in northern South America and Brazil, favouring areas of dense rainforest, drier woodlands and open grasslands. They have specifically been found to be frequent in the Cerrado, a vast expanse of tropical savanna in central Brazil. Greater grisons have been noted to be found most often in proximity of riverine systems. They are most common at elevations below 500m (1,600ft) but the Andean subspecies; ***(G. v. andina)*** occurs as high up as 2,000m (6,600ft) in the tropical mountains of Peru and Bolivia. The population of the greater grison and its subspecies is unknown however, it has been noted as one of the "less known carnivores of South America", according to the IUCN, suggesting a possibly small or less dense yet stable population.

## Behaviour

The greater grison is a mostly solitary species however, may travel in pairs. When travelling, the greater grison will move quickly and in a zig-zag pattern according to the Animal Diversity Web (ADW). They are known to be mostly terrestrial however, they are also well-adept swimmers and have been observed partly climbing shorter trees. Greater grisons are cautious and will periodically raise their head from the ground to survey their surroundings while moving through long grasses. When in the company of others, the greater grison has been observed to display playful behaviours, often gently biting and wrestling with each other, though social grooming has not yet been observed. When threatened, a greater grison will leap backwards, growl or snarl and emit a fowl odour in a similar manner to skunks ***(Mephitidae)***. The spray is secreted as a yellow-green liquid from the anal glands. Greater grisons have the ability to aim this spray in a controlled area, often using it directly against threats. They also use this spray to mark territory. It is disputed whether the greater grison is a diurnal or nocturnal species, as it has been observed to be active at both day and night however, most researchers agree the species is crepuscular, being most active around dawn and dusk. The breeding habits of the greater grison are seldom-studied however, the species is suspected to be monogamous on the basis that the closely related lesser grison ***(G. cuja)*** is known to be monogamous. Offspring has been noted as abundant throughout the months of March and October, with the exception of April and July. The gestation of the female grison lasts 39 days, with up to four offspring being produced, though the average litter size is just one. Grisons are born with short hair and closed eyes, first opening them after one week. Grisons already begin eating meat at two weeks, though they are not fully weaned until about three and a half weeks. Greater grisons mature at four months. Groups of grisons hunted together have been suspected to be mother-offspring parties, likely implying a lasting bond between mother and offspring proceeding weaning.

### Relationship with Humans

The greater grison is hunted through much of its range for the use of its body parts by native tribes. It is also trafficked for its role in the illegal pet trade, being one of the most confiscated species in Colombia. Greater grisons have also been known to occasionally prey on domestic chickens ***(Gallus gallus)***, leading to some agricultural conflicts.

## In Captivity

Greater grisons are housed infrequently in zoos, but are abundant as pets, often being likened as friendly, inquisitive and affectionate. In some cases, grisons are adopted to eradicate rodent infestations.

## Sources

* IUCN Red List of Threatened Species - https://www.iucnredlist.org/species/41640/45211961
* Greater Grison | Wikipedia - https://en.wikipedia.org/wiki/Greater\_grison
* Greater Grison | Animal Diversity Web, University of Michigan Museum of Zoology - https://animaldiversity.org/accounts/Galictis\_vittata/
* Furão grande | Onçafari - https://oncafari.org/especie\_fauna/furao/
* Greater Grison | Zoo Institutes - https://zooinstitutes.com/animals/greater-grison-5073/