Seasonality, morphometrics and feeding behaviour of sailfish (Istiophorus platypterus) caught by sports fishers in the Kenyan waters

Sailfish (Istiophorus platypterus) are among the major target species caught by sports fishers in Kenyan waters. As a conservation measure, sports fishers return the fish to the waters and also tag them in an effort to study them. The retained fish are mainly those injured during the fishing expedition, they are brought on board and these were the ones used for the study which was conducted between November 2012 and January 2013 which is the peak season for sailfishes in the Kenyan waters. For seasonality data, a 19 year daily catch data from 1987 to 2011 was used. The December and January happen to have the peak abundance of sailfish in the waters. They average weight of the sailfish was recorded as 28.9 ± 4.4 kgs and had an average eye-orbit fork length of 166.5 ±9.5 cm. The major food contents in the fish stomachs were crabs (Charybdis smithii) sardines Stolephorus commersonii (Lacepède, 1803) and Kawakawa (Euthynus affinis).