Diversity of reef fishes in trap fishery at Keelakarai, Gulf of Mannar, south-east coast of India

Abstract

The diversity of finfishes caught in traps at Keelakarai, Gulf of Mannar was assessed quantitatively and qualitatively for a period of six years from July 2006 to June 2012. Average landing during the period was 109 t per year with maximum of 137 t during 2008-09. Among the 98 species of reef fishes landed, Siganus canaliculatus dominated (28%), followed by Scarus ghobban (21%). During the first two years of the study, S. ghobban dominated over S. canaliculatus and later the trend reversed. Family-wise, maximum contribution was by Siganidae (36%) followed by Scaridae (21%). Seasonally, the major peak was recorded during post-monsoon of 2009. The Shannon index of diversity was maximum during 2007-08. Cluster analysis indicated the highest similarity in species composition between 2010-11 and 2011-12. SIMPER analysis identified 26 species as most significant in creating the observed pattern of similarity for 90% cut off contributions. Ellipse plot showed statistically significant deviation in fish diversity between years. Reef fish landings showed an increasing trend from 2006-07 to 2008-09, a decline afterwards and then almost steady condition prevailed during the last two years of the study which implies that there is no scope for further increase in landings by trap fishery at Keelakarai.

Assessing the ichthyofaunal diversity and trophic level from trawl bycatch of Chennai Fishing Harbour, Southeast Coast of India

“…In this study, Leiognathus equulus contributed 7.97% (with 1.47% average similarity) to the total similarity of trawl bycatches of Chennai coast. Meanwhile, Varghese et al (2017) reported that Siganus caniculatus contributed a maximum of 23.82% similarities to total similarity of reef fishes between the 2006 and 2012 along the southeast coast of India. The 95% confidence funnel of average taxonomic distinctness index (∆+) and variation in taxonomic distinctness index (/\+) values, showed no significant deviation in bycatch fish diversity between the seasons.…”

“…The 95% confidence funnel of average taxonomic distinctness index (∆+) and variation in taxonomic distinctness index (/\+) values, showed no significant deviation in bycatch fish diversity between the seasons. Varghese et al (2017) stated that 95% probability contours showed significant deviation in reef fish diversity at Keelakarai, Gulf of Mannar between 2006 and 2012. In this study, the 95% probability contours of average taxonomic distinctness index (∆+) and variation in taxonomic distinctness index (/\+) values were well within the funnel showing no significant deviation.…”

Impact of Covid-19 lockdown on trap fishery in Olaikuda Region of Palk Bay, South India

“…Seasonal abundance of coral reef-associated shes has been studied in Keelakarai region (Murugan & Durgekar, 2008) along with the diversity, occurrence, economic aspects of snappers and job sh sheries in the Gulf of Mannar region (Murugan et al, 2014). Comparative performance of three types of traps and diversity of reef shes collected from the trap shery at Keelakarai, Gulf of Mannar was described (Kalaiarasan et al, 2014;2015 andVarghese et al, 2017). With this backdrop, the present work was carried out to understand the catch and value of shes collected through trap shing and in uence of COVID-19 lockdown on the sh market value.…”

“…This method targets the catch of coral reef-associated shes (Varghese et al, 2008;Murugan and Durgekar, 2008). Many people prefer the trap shery in this region due to less capital investment for construction of traps, easy to haul from small traditional craft (Kattumaram) and high income accrued from the trap shery (Varghese et al, 2017). The variety of shes from the trap shery includes Parrot sh, Groupers, Rabbit sh, Emperors, Snappers, Goat shes, Grunts, Thread n bream, Trevally sh, trigger sh, Puffer sh and Porcupine sh.…”

Population dynamics of a poorly known serranid, the duskytail grouper Epinephelus bleekeri in the Arabian Sea

“…It is a relatively small yet important fishery in the range countries (Heemstra & Randall, 1993;Kandula et al, 2015;Russell et al, 2008), but due to declining populations because of exploitation for both capture fisheries and capture-based aquaculture, E. bleekeri has been assessed as Near Threatened (Russell et al, 2008). In India, E. bleekeri is exploited along the western and eastern coasts using trawls and traditional fishing gears (Kandula et al, 2015;Mathew, 2003;Vargese et al, 2017), but no information is available on the magnitude of catches, status and dynamics of populations or other fishery-induced wffect. This data deficiency on the demography and fishery status of E. bleekeri in India, where a major fishery exists and throughout its range, poses a significant challenge to their effective management and hampers updated species assessments for the IUCN Red List.…”