The conservation status of decapod crustaceans in the Western Ghats of India: an exceptional region of freshwater biodiversity

Abstract

ABSTRACT1. Freshwater invertebrates receive relatively little publicity and conservation attention, in spite of their key role in aquatic food webs and ecosystem functioning.2. Decapod crustaceans such as caridean shrimps and gecarcinucid freshwater crabs comprise some of the most poorly known aquatic taxa, even in exceptional regions of freshwater biodiversity and endemism, such as the Western Ghats mountains of peninsular India.3. An analysis was carried out to understand distribution patterns and identify priority areas for decapod crustacean conservation in the Western Ghats region based on conservation status data retrieved from the IUCN Red List of Threatened Species.4. The Western Ghats region is home to 49 species and six sub-species of caridean shrimps (69% endemism) in four genera and two families, and 39 species of gecarcinucid crabs (92% endemism) in 14 genera. This diversity is probably an underestimate given the lack of biotic surveys and taxonomic research carried out on these groups.5. Three species (3%) of decapod crustaceans from the Western Ghats region are threatened with extinction, while more than half (51%; 48 species) are Data Deficient. The uncertainty regarding the true extinction risk of such a high number of Data Deficient species could hamper conservation efforts as well as policy development and implementation.6. Forty sites in the Western Ghats region are priorities for the conservation of decapod crustaceans, of which only seven lie within the existing network of protected areas.7. The specialized natural history and point endemic nature of many species of freshwater decapods, together with escalating human impacts on their aquatic ecosystems in the Western Ghats, makes conservation and management of these threatened and poorly-known species an immediate and urgent challenge.

Protected areas and imperilled endemic freshwater biodiversity in the Western Ghats Hotspot

“…102 National Parks/IUCN Category II, 527 Wildlife Sanctuaries/IUCN Category IV, 57 Conservation Reserves/IUCN Category V and four Community Reserves/IUCN Category VI) (Juffe‐Bignoli et al ., ; MoEF, ); with a vast majority of them established for protecting charismatic mega‐vertebrates and birds. The Western Ghats region, part of the Western Ghats–Sri Lanka Biodiversity Hotspot harbours extremely high levels of endemism for freshwater‐dependent taxa such as crabs (92%), amphibians (87%), shrimps (69%) and fish (59%) (Dahanukar and Raghavan, ; Raghavan et al ., ; S. Das, Unpubl.) with the majority of endemic species restricted to the southern region, within the state of Kerala (Dahanukar et al ., ; Dahanukar and Raghavan, ; Raghavan et al ., ).…”

“…The Western Ghats region, part of the Western Ghats–Sri Lanka Biodiversity Hotspot harbours extremely high levels of endemism for freshwater‐dependent taxa such as crabs (92%), amphibians (87%), shrimps (69%) and fish (59%) (Dahanukar and Raghavan, ; Raghavan et al ., ; S. Das, Unpubl.) with the majority of endemic species restricted to the southern region, within the state of Kerala (Dahanukar et al ., ; Dahanukar and Raghavan, ; Raghavan et al ., ). Although Kerala's first PA was created in 1950 (Kerala Forest and Wildlife Department, ), further expansion has been limited, and only 8% of the total area of the state is currently within the PA network.…”

Selective and Interbreeding of Freshwater Ornamental Shrimps with Endemic Aquarium Plants

“…Their biology, behavior, adaptability in aquarium conditions and color enhancement by feed formulations and selective breeding are being studied. Currently the industry is completely depends on the wild caught species (Raghavan et al, 2014). Breeding and production of high grade 'Rainbow shrimps', 'Stripe shrimps', 'White banded shrimps' will definitely reduce the stress on the wild population.…”

The legendary hump-backed mahseer Tor sp. of India’s River Cauvery: an endemic fish swimming towards extinction?

“…The Western Ghats region of India, part of the Western Ghats-Sri Lanka Biodiversity Hotspot, is an area of exceptional freshwater biodiversity and en demism , Raghavan et al 2015. Nevertheless, approximately half of the region's endemic fish species are threatened with extinction ), a result of escalating anthropogenic pressures and threats, lack of governmental support for freshwater fish conservation, jurisdictional issues and oversights, poor enforcement of existing laws and implementation of top-down approaches , Pinder & Raghavan 2013).…”