The fishing cat (Prionailurus viverrinus) got its Latin name because of its rather viverrine or civet-like appearance and its preference for fish prey. Two subspecies of the fishing cat are recognised:

• Prionailurus viverrinus viverrinus in India, Sri Lanka, Pakistan, Bangladesh, Indochina, Nepal and possibly Bhutan and
• Prionailurus viverrinus rhizophoreus on Java

However, further research on its geographic variation is needed to clarify its taxonomy.

The fishing cat is a middle sized cat and is often confused with the leopard cat. Its fur is short, coarse, and grey or olive brown. The head and body are conspicuously marked with small black spots and stripes. On the face, back and neck the spots merge into short lines. Its belly is white and there are two dark collars on the throat. The head is relatively big and broad with small, rounded ears. The backs of the ears are black with white central spots. The thick muscular tail is very short for a felid and measures only about one third of the total head and body length. The tail is marked with 5-6 black rings and a black tip. The fishing cat's legs are short, stocky and powerfully built. The claws have incomplete sheaths so that they are not completely enveloped when retracted. Despite their fishing activity, the fishing cat does not show marked morphological adaptations for capturing or eating fish. Their hind feet are webbed but the webbing beneath the toes is not much more developed than that of a bobcat, and unlike the flat-headed cat, in which the second upper pre-molar is long and sharp (which enables it to grip slippery prey), the fishing cat has a much smaller and less developed tooth. Females are markedly smaller than males. 

Exclusively in the Haor Basin of Bangladesh, a few albino individuals have been found.

The fishing cat is classified as Vulnerable in the IUCN Red List. It is thought to be widely distributed through a variety of different habitat types and is assumed to be common with a highly localised occurrence around wetlands. It is listed as Endangered in the National Red Lists of Bangladesh and Nepal.

The species is in decline within all range countries at an alarming rate, mainly in South-east Asia. The fishing cats range is highly localised in all range countries except West Bengal, India, Bangladesh and Sri Lanka. The species is mainly recorded in the Terai region of the Himalayan foothills, eastern India into Bangladesh where it is locally common in some regions. Historically, the fishing cat occurred throughout tropical Asia from India, Sri Lanka and Nepal to most of South-east Asia including the islands of Java and possibly Sumatra. Currently, the fishing cat has a discontinuous distribution in mainland tropical Asia with large areas where it is absent, extirpated or where it has not yet been detected. It is found in South and South-east Asia from Pakistan to Cambodia south to Thailand. It is also found on the islands of Sri Lanka and Java. Its current status in South-east Asia is not clear and there have been drastic declines in fishing cat populations throughout much of their Asian range over the last decade. Only very few recent records exist from Cambodia, Indonesia, Java, Myanmar, Thailand and Vietnam and the species has a highly patchy distribution. The regular confusion with the leopard cat has led to an overestimation of its range, and the species might be less common than formerly thought. Thus, further investigation on its actual distribution is required.

In Pakistan, the species was only recorded in the Sindh Province. In India, it was recorded in some protected areas in the provinces Uttar Pradesh, Madhya Pradesh, Uttarakhand, West Bengal, Rajasthan, Assam, Andhra Pradesh and in Arunachal Pradesh. Records form unprotected areas exist from Uttar Pradesh, West Bengal, Odisha and Andhra Pradesh. In the Sundarbans on the Sagar Island the fishing cat has been extirpated according to the local people while in other parts of the Sundarbans the fishing cat seems to do better. There are no records of fishing cat along the western Indian coast, but it is unsure whether fishing cats ever occurred there. In large areas of India it has been extirpated such as in the Bharatpur region. In Sri Lanka, it seems to occur over the whole island and has even been recorded on watercourses close to the capital city. In Bangladesh, fishing cats are found in the Sundarbans and the Chittagong Hill Tract. In fact, the National Red List of Bangladesh describes it as widely distributed in the countryside and all kinds of natural forests and wetlands, albeit at low density. However, populations are thought to be declining and only a very small population is thought to remain despite the wide distribution in the country. In Nepal, it is found along the border to India. It was detected in the far western and central Terai and is present in parts of south-western and south-eastern Nepal. In Vietnam, the fishing cat could not be confirmed in any reserves during the last survey and may be extinct. However, it possibly still occurs in the Mekong Delta. It probably occurred in southwestern China but this is not confirmed. Its occurrence in Lao PDR is also uncertain and needs further investigation. Its distribution in Cambodia is poorly known. In 2003, it was recorded in the Kulen Promtep Wildlife Sanctuary in northern Cambodia, in 2008 it was detected in the Botum-sakor National Park in southwest Cambodia, and in 2015 Peam Krasop Wildlife Sanctuary and in Ream National Park. In Myanmar the fishing cat was recently recorded in the Ayeyarwady Delta. The only other known record of verifiable origin of fishing cat from Myanmar is from 1935 from the Hukaung Valley Wildlife Sanctuary. A review of fishing cat records from Thailand found only one record from Upper Central Thailand, and only few from the Inner Gulf of Thailand and Peninsular Thailand, respectively.  From Java records are missing since 2000. Its presence on Sumatra is disputed as there are no confirmed records and photos first identified as fishing cat all turned out to be leopard cat on a second look.

In the Chitwan National Park, Nepal, the density of fishing cats was estimated at 4.37-6.06 individuals per 100 km². In the Coringa Wildlife Sanctuary in Andhra Pradesh, India, the density was estimated at 53 individuals per 100 km² and in the Lothian Wildlife Sanctuary in the Sundarbans at 44 ± 13 individuals per 100 km².  In Khao Sam Roi Yot National Park, Thailand, a density of 14.23 ± 3.2 individuals was estimated.

The fishing cat is strongly associated with wetlands. It lives typically near water and where thick cover is available. It can be found in habitats such as swamps and marshy areas, mangroves, oxbow lakes, reed beds, tidal creeks and along watercourses. The fishing cat is not so common around fast-moving watercourses. In Sri Lanka, India and Nepal, they live in forests, shrubs, reed beds and tall grass areas. The fishing cat has been recorded in degraded habitats such as the aquaculture ponds outside of the city of Calcutta in India. One fishing cat was captured and collared in a highly urbanised area of Sri Lanka’s capital city of Colombo, several kilometres away from wetlands, where it was observed to prey on fishing ponds. It is also reported to be common around villages in wetland areas where habitat destruction has not been significant. The fishing cat seems not to use rice paddies and other irrigated forms of cultivation.

Most records of the fishing cat come from lowland areas but in the Himalayas in India it has been recorded up to 1,525 m.

The fishing cat is largely described as nocturnal or crepuscular. However, a study in the mangroves of Coringa Wildlife Sanctuary, India, found large differences between individuals with some being mostly diurnal. The fishing cat spends most of its time in dense cover. It is an excellent swimmer and diver over long distances. The fishing cat hunts alone. It has been observed hunting mostly in shallow water where it uses the webbed hind feet to push itself along leaving the front feet ready to grab fish. It has been observed diving into water after fish as well as attempting to scoop them out of water with its paws. Fishing cats were reported to catch waterfowl by swimming up to them while fully submerged and seizing their legs from underneath. However, it is suggested that the species prefers hunting in shallow waters, as the submergence of the body results in the loss of more body heat/energy.

The home range size of female fishing cats in Nepal’s Chitwan National Park was 4-6 km². A male had a home range of 16-22 km². In Thailand, a male had a home range of 11-13 km², and a female had a home range of 4 km².Male home ranges enclose several female home ranges and both sexes use scent for marking. In the mangroves of Coringa Wildlife Sanctuary, India, considerable amounts of home range overlap were observed between individuals of the same sex, too. However, individuals of the same sex overlapping spatially largely showed temporal avoidance through their activity patterns.

The fishing cat’s peak in mating activity in coastal wetlands of northeastern India occurs in January to February with births taking place from March to May. Mating is also observed in June. The gestation period lasts for 63-70 days. At the age of 10 months, fishing cats become independent. 

In Sri Lanka, five claws of a fishing cat were found in the guts of a dead saltwater crocodile (Crocodylus porosus).

The fishing cat is included in the CITES Appendix II. It is protected over most of its range and hunting is prohibited in Bangladesh, Cambodia, China, India, Indonesia, Lao PDR, Myanmar, Nepal, Pakistan, Sri Lanka, Thailand and Vietnam. There is no legal protection outside of protected areas in Nepal. In India, it is accorded the highest protection by being placed in Schedule I of the Indian Wildlife Protection Act. The fishing cat occurs in protected areas such as the Sundarbans (Bangladesh and India), Chitwa (Nepal), Corbett, Dudwha and Kaziranga (India). It can be found in and around various protected areas, e.g. Khao Sam Roi Yot and Thale Noi in Thailand, Botum-Sakor and Ujung Kulon in Cambodia and in Pulau Dua on Java.

One of the most important aspects in regard to the conservation of the fishing cat is the protection and sustainable use of wetland areas. There is a need for more comprehensive surveys for fishing cats to better understand its ecology, status and actual distribution and the phylogenetic relation between isolated populations. Effective measures to prevent indiscriminate trapping, snaring and poisoning are required. The inclusion of local people into the conservation of the fishing cat is very important. A conservation project of the fishing cat taking place in Thailand includes a strong public education feature as it attempts to reverse the trend of persecution of the fishing cat. An Indian conservation organisation also recently started a public survey about the fishing cat and an education program to promote conservation awareness. Some Sri Lankan hotels use the fishing cat as focal species to promote ecotourism.

A Fishing Cat Working Group was established in 2011. At the First International Fishing Cat Conservation Symposium in 2015, a Fishing Cat Conservation Strategy was developed. A Second International Symposium on Fishing Cat Conservation was held in 2018.