Puntius denisonii (Day, 1865) an endemic ornamental barb of the Western Ghats of India belongs to the family Cyprinidae. It is a much sought after fish in the international ornamental fish market. Puntius denisonii is distributed in twelve rivers includes, River Chandragiri, River Karingode, River Kuppam, River Valapattanam, River Anjarkandipura, River Kuttiyadi, River Chaliyar, River Chalakudy, River Bharathapuzha, River Bhavani, River Periyar and River Pampa in Kerala and River Payaswany in Karnataka.P. denisonii prefers to inhabit in a narrow range of microhabitats, at the pool-riffle or rocky pool habitats with cobbles, gravels and at some rare occasion s even sand as substratum.With the high demand and pricing of many beautiful species, ornamental fish are being harvested at greater volumes and higher rates, threatening the viability or sustainability of the stock.In order to manage endangered species effectively, it is necessary to identify the reason for decline and a severe understanding of the ecology of the target species . Over the last few decades wild population of P. denisonii has been declined due to various reasons and species belonging to the Vulnerable category of threatened fishes . but recently completed IUCN Freshwater Biodiversity Assessments in the Western Ghats has categorized this species as Endangered.
The fish body of P. denisonii is torpedo shaped with silver scales, a red line running from their snout through the eye; back towards the middle of the body and below the red line a thick black line that runs the length of the fish from snout to the caudal peduncle. Mouth is sub terminal and inferior; one pair of barbel with equal to the length. As they mature, a distinctive greenish blue marking on top of the head developed.
The populations of Puntius denisonii are declining due to a combination of over exploitation, river pollution, destruction of breeding grounds, various ecological changes in its natural habit, and lack of proper management. Spawning of P. denisonii occurs during the months of November to April and attains the sexual maturity in the first year of its life . A total ban should be put to destructive fishing practices and law enforcement enhanced, during the spawning season will reduce the threats to the species. As an exsitu conservation practices, development of artificial breeding of the species have also been standardised by College of fisheries, Kerala University of fisheries and Ocean studies (KUFOS) in Kerala, India under Marine Products Export Development Authority Project . Using this technology, river ranching of the young ones can be considered as an exsitu conservation measures. Identify fish congregation places including the existing ones and officially declare them as `Sanctuaries' as an insitu conservation measures.
Anna Mercy, T.V., Malika, V and Sajan, S. (2010). Breakthrough in Breeding of Puntius denisonii. Info fish international. ISSN: 1511-5976. 7/8(4): 14-17.
Sajan S., Anna Mercy T.V., Malika V. 2011. Successful captive breeding, Early embryonic and larval development of Puntius denisonii (Day, 1865) (Osteichthyes: Cyprinidae) - An endemic ornamental barb of the Western Ghats hotspots of India. Pp 84. In: Giant Prawn- Asia-Pacific Aquaculture 2011, Asia Pacific Chapter of WAS (WAS-APC), Kerala, India.