- The fishing cat is a primary predator in India’s intricate ecosystems of mangroves, swamps, wetlands, and riverine habitats. It is classified as vulnerable on the IUCN Red List.
- A recent study looked at the feeding patterns of these felines in the Godavari Delta in Andhra Pradesh. It sheds light on the diverse dietary spectrum of this keystone species, emphasising its significance in the delicate balance of these vital ecosystems.
- It showed that fish dominate the diet of fishing cats in the area, comprising 61.6% of their prey. Crabs and rodents followed, making up 30% and 28.3% of its diet, respectively.
In the intricate ecosystems of India’s mangroves, swamps, wetlands, and riverine habitats roams a silent predator: the enigmatic fishing cat. Early research suggests its piscivorous nature, but few studies have delved into its dietary habits. The understanding of the cat’s diet is crucial for safeguarding the long-term survival of the species, classified as vulnerable on the International Union for Conservation of Nature’s (IUCN) Red List.
Mangroves, which serve as nurseries and habitats for numerous fish species, offer a particularly rich food source for fishing cats. To bridge the gap in this understanding, a recent study looked at the feeding patterns of these felines in the Godavari Delta in Andhra Pradesh and shed light on the diverse dietary spectrum of this keystone species, emphasising the fishing cat’s significance in the delicate balance of these vital ecosystems.
“These nocturnal predators consume a diverse range of prey. This dietary diversity positions them as primary predators within mangrove habitats, alongside other significant species such as the golden jackal and the smooth-coated otter,” says Giridhar Malla, founder of the Godavari Fishing Cat Project and member of the IUCN/SSC Cat Specialist Group, who is also the lead researcher of the study.
Location matters
The Godavari delta and the Coringa Wildlife Sanctuary in Andhra Pradesh comprise the second-largest contiguous mangrove forests in India, after the Sundarbans in West Bengal. They also support a high density of fishing cats. Previous records and sightings have provided accessibility and conducive conditions for research, which made extensive observation of these elusive felines feasible in their natural environment for the purpose of this study.
As part of the research, 303 fishing cat scats were collected and a dietary analysis was conducted using 120 genetically identified scats. The findings of this comprehensive approach revealed that fish dominate the diet of fishing cats in the area, comprising 61.6% of their prey. Crabs and rodents followed, making up 30% and 28.3% of their diet, respectively.
The researchers also identified 393 prey items, including fish scales, otoliths and bones, feathers and bones of birds, the carapace of crabs, rodent bones, teeth mandible and hair strands, snake bones and scales, and other remains belonging to molluscs and insects. Spread across 15 taxa, this analysis revealed a diverse array of food sources preferred by these elusive cats. It confirmed that while fish remained the primary dietary component, consistent with previous research, birds, snakes, molluscs, and insects were also an integral part of the cats’ diet.
There were other notable findings linked to seasonal and yearly fluctuations, underscoring the fishing cat’s adaptable and opportunistic feeding behaviour. For instance, there was an observed increase in specialisation among fishing cats, particularly during the summer months, potentially in response to an increase in fish availability. During this period, when many estuarine fish species breed, fishing cats displayed a preference for mullets, likely due to their abundance and feeding patterns within mangrove habitats.
The research also revealed that fishing cats strategically capitalise on optimal hunting conditions, such as exposed intertidal zones during low tides, to maximise their fishing success in mangrove creeks. Seasonal analysis highlighted variations in the fishing cat’s diet, with fish dominating during summer, while birds gained importance as prey items during winter (the delta is stop-over point for migratory birds) and rainy seasons (large parts of the mangroves are submerged due to the flooded Godavari River, leading to a reduced exposure of the intertidal zone), reflecting seasonal shifts in prey abundance.
“These findings will enhance our understanding of wild fishing cats’ ecology and underscore the dynamic interplay between predators and their environment in mangrove ecosystems, which otherwise is very difficult to understand,” says Malla.
Under threat
The study also noted that the long-term well-being and survival of fishing cat populations significantly depends on the abundance of fish, their primary prey. But the researchers observed a notable depletion in fish populations within the Godavari delta, corroborated by local fishermen who reported the disappearance of several fish species. “The Indian major carps have reached the saturation point. The catfishes such as Wallago attu, Bagarius bagarius and Pangasius pangasius have declined in their population drastically,” says Karthik Reddy, a fisherman in East Godavari.
This trend underscores the critical necessity of safeguarding fish populations within the Godavari delta and its adjacent riverine habitats. “The ecological health of the Godavari River and its deltaic ecosystem is intricately linked to the conservation of this keystone species,” says Malla.
The researchers also highlighted the crucial ecological role that fishing cats play by regulating rodent populations. Left unchecked, these rodents pose a significant threat to mangrove ecosystems by consuming juvenile saplings and impacting adjacent paddy fields, which are vital for local farmers and fisherfolk.
Yet, despite their ecological significance, fishing cats remain relatively understudied and undervalued in terms of their contribution to ecosystem services for local communities. Today, there are several threats to the fishing cat’s habitat in the Godavari delta. This includes the degradation and loss of intact mangrove forests, their primary habitat, exacerbated by sea-level rise, which leads to coastal erosion and inundation of these areas. “For instance, approximately 50 hectares of mangrove forests, crucial for fishing cats, were lost to coastal erosion by 2024. This loss diminishes the cats’ habitat and pushes them towards degraded areas,” emphasises Malla.
Large-scale infrastructure projects, such as the Polavaram Dam, disrupt natural riverine systems upstream of the Coringa Wildlife Sanctuary. Furthermore, regulating river flow due to numerous dams and barrages across the Godavari River and its tributaries decreases sediment deposition, which negatively impacts delta formation and progradation. The encroachment of mangrove areas for shrimp farming and the expansion of aquaculture ponds are also major issues, causing habitat fragmentation and degradation. Additionally, the reduction in freshwater flow impacts estuarine ecosystems and fisheries, a crucial food source for fishing cats.
It indicates an urgent need for concerted conservation efforts, with community involvement being crucial for the sustained survival of fishing cats in the region. The study finds that engaging local fishing communities as key allies in conservation efforts is vital, as is implementing successful and sustainable mangrove restoration initiatives to enhance habitat connectivity and support the thriving of fishing cats within human-dominated landscapes.
At the same time, maintaining adequate river flows is imperative for mitigating negative impacts such as heightened salinity levels. “Establishing well-defined buffer zones between mangroves and aquaculture ponds is critical to facilitate the landward migration of mangroves in response to rising sea levels. Additionally, raising awareness about the benefits of integrated mangrove aquaculture can incentivise the protection of native mangrove species and contribute to habitat restoration efforts,” says Malla.
The findings of this study extend beyond the Godavari delta, holding relevance for fishing cat populations across India and beyond. “Such knowledge empowers collaborative efforts involving diverse stakeholders at both regional and national levels, thereby enhancing conservation initiatives for these threatened feline species,” says Malla.
Banner Image: Fishing cat in Coringa Widllife Sancutuary. Photo by Giridhar Malla.