Javan mongoose

Taxonomy

Ichneumon javanicus was the scientific name proposed by Étienne Geoffroy Saint-Hilaire in 1818. In the 19th and 20th centuries, several zoological specimens were described, which are now considered synonyms:

• Mangusta auropunctata by Brian Houghton Hodgson in 1836 was a specimen collected in central Nepal.
• Herpestes exilis by Paul Gervais in 1841 was a specimen from Tourane in Vietnam.
• Mangusta pallipes by Edward Blyth in 1845 were mongooses observed in Kandahar, Afghanistan.
• Mungos rubifrons by Joel Asaph Allen in 1909 were eight adult specimens collected around Wuzhi Mountain in Hainan Island, China.
• Mungos exilis peninsulae by Ernst Schwarz in 1910 was a skin and a skull of a mongoose collected in Bangkok.
• Mungos siamensis by Cecil Boden Kloss in 1917 was a skin of an adult female mongoose collected in northern Thailand.
• Herpestes palustris by R. K. Ghose in 1965 was an adult male mongoose collected in a swamp on the eastern fringe of Kolkata, India.

Today, the following Javan mongoose subspecies are recognised:

• H. j. javanicus
• H. j. auropunctatus
• H. j. exilis
• H. j. orientalis
• H. j. pallipes
• H. j. palustris (Bengal mongoose)
• H. j. peninsulae
• H. j. perakensis
• H. j. rafflesii
• H. j. rubrifrons
• H. j. siamensis
• H. j. tjerapai

Phylogeny

Analysis of mitochondrial DNA revealed that the Southeast Asian group of Javan mongoose subspecies differs genetically from the Javan mongoose occurring farther west. The Salween River in Myanmar is probably a barrier between the two groups.

Description

The body is slender and the head is elongated with a pointed snout. The length of the head and body is 509–671 millimetres (20.0–26.4 in). The ears are short. The feet have five toes and long claws. Sexes differ in size, with males having a wider head and bigger bodies.

The Javan mongoose can be distinguished from the sympatric Indian grey mongoose (H. edwardsii) by its somewhat smaller size. It is larger in the east of its range, where the Indian grey mongoose does not occur, and shows a stronger sexual dimorphism, with the males being larger than the females.

Distribution and habitat

The Javan mongoose is native to the north of the Middle East, South and Southeast Asia, and has been introduced to Hawaii, the Bahamas, Cuba, Croatia, Jamaica, Hispaniola, Puerto Rico, the Lesser Antilles, Belize, Honduras, Panama, Trinidad and Tobago, Colombia, Suriname, Venezuela, Guyana and Mafia Island. It lives in a broad diversity of habitats.

Introduction to Hawaii

In the 1800s sugar cane plantations shot up on many tropical islands, including Hawaii, Fiji and Jamaica. With sugar cane came rats, attracted to the sweet plant, which caused crop destruction and loss. Attempts were made to introduce the mongoose in Trinidad in 1870 to control the rats, but this failed. A subsequent trial with four males and five females from Calcutta, however, established the species in Jamaica in 1872. A paper published by W. B. Espeut that praised the results intrigued Hawaiian plantation owners, who, in 1883, brought 72 mongooses from Jamaica to the Hamakua Coast on the Big Island. These were raised and their offspring were shipped to plantations on other islands.

Accounts from the sugar industry in the early 20th century state that the introduced mongooses were effective at reducing the number of rats, mice, and insects. However, the mongooses have been deleterious to native birds, which evolved in the absence of mammalian predators, as well as preying on the eggs of endangered sea turtles.

Only the islands of Lana'i and Kaua'i are thought to be free of mongooses. There are two conflicting stories of why Kaua'i was spared. The first is that the residents of Kaua'i were opposed to having the animals on the island, and when the ship carrying the offspring reached Kaua'i, the animals were thrown overboard and drowned. A second story tells that on arriving on Kaua'i one of the mongooses bit a dockworker, who, in a fit of anger, threw the caged animals into the harbor to drown.

Introduction to Caribbean

Starting in 1870, the Javan mongoose was introduced to Jamaica, Cuba, Hispaniola, St. Croix (1884), to prey upon black rats (Rattus rattus) that were ravaging the sugarcane industry. Another reason for introducing the mongoose was to reduce snakes in the cane fields. While successful in reducing sugarcane damage from rats, the introduction had a negative impact on reptiles and other animals. The green iguana (Iguana iguana, also believed to be an introduced species) has been greatly reduced in number and the ground lizard Ameiva polops was eliminated from the island of St. Croix before 1962 (but not from Protestant Cay, Green Cay, Ruth Cay, and Buck Island). Ground-nesting birds may also have been affected.

Introduction to Okinawa

The mongoose was introduced onto Okinawa Island in 1910 and Amami Ōshima Island in 1979 in an attempt to control the population of the venomous snake Protobothrops flavoviridis, an endemic species, and other pests, but they have since become pests themselves.

Behaviour and ecology

The Javan mongoose uses about 12 different vocalizations. It is mostly solitary; males sometimes form social groups and share burrows. Females are pregnant for up to 49 days and give birth to a litter of 2–5 young. Males can potentially become sexually mature at the age of 4 months.

Javan mongooses eat mostly insects but are opportunistic feeders and will eat crabs, frogs, spiders, scorpions, snakes, small mammals, birds and eggs.

Mongooses can carry leptospirosis, and are a major rabies vector in Puerto Rico (although actual incidence of transmission to humans is low). On Okinawa, the Javan mongoose may carry antibiotic-resistant strains of E. coli.

In studies where traps were used in an attempt to remove the mongoose, it was found that the trap success was nearly zero during rain.

Genetics

The introduced populations show genetic diversification due to drift and population isolation. Populations on islands throughout the world have increased in size and sexual dimorphism, resembling populations in the east of their range where they have no ecological competitors.

Invasive species

Mongoose introduction was very successful in rat control, but the mongoose also hunts reptiles, birds and bird eggs, threatening many local island species.

It has also been extremely successful regarding its second purpose in getting rid of snakes; on many of the Caribbean islands where it was released the native snakes have been extirpated and now only exist on offshore islands, at least one species from St. Croix in the Virgin Islands may now be extinct.

In 2016, the European Commission put the mongoose on the list of invasive alien species in the EU.