Circannual production rhythms of seven commercially important fishes in the Chilika lagoon

Abstract

ABSTRACT The main objective of this investigation was to delineate spatiotemporal patterns in annual production of seven species of fishes inhabiting the famous Chilika lagoon. The data were collected from 19 landing centers located across four different geographical sectors of the lagoon over a period of two consecutive years. Using Cosinor rhythmometry, statistically significant circannual rhythms of production in all seven species of fishes were validated at the group level either at one or multiple landing centers of the lagoon. The peaks of the circannual rhythms were subjected to Bray–Curtis cluster analysis and similarities among the landing centers apropos the peak timings of the circannual rhythms in production of fish species was determined. Three distinct clusters were witnessed apropos the peaks at different time of the year and at different sectors of the lagoon. This spatiotemporal relationship reflects how temporal abundance of fish species is distributed to avoid conflicts and competitions among themselves along the annual time scale. The findings reported here might help in making strategy to maximize annual fish yield. That will also help in the management of biodiversity of the lagoon.