Abstract:
Based on the survey data from September to October in 2012, we analyzed the fishing ground and catch composition of large-scale light falling-net fishery in the central and southern South China Sea in autumn. According to the index of relative importance (IRI),
Sthenoteuthis oualaniensis and
Katsuwonus pelamis were the dominant species;
Euthynnus affinis, Auxis thazard and
A.rochei were the major species;
Decapterus macarellus and
D.macrosoma and so on were the common species. Generally,
S.oualaniensis, tuna species and round scad were the main species which accounted for 48.35%, 48.33% and 0.98% of the total catches, respectively, and small tunas occupied 47.77% of the total. The catch rate varied significantly among different fishing grounds, which was 411.47 kg · h
-1 in Xisha and Zhongsha waters but only 25.66 kg · h
-1 in Nansha waters. The central fishing ground was located in waters of 12°30′N~15°30′N, 110°30′E~115°00′E. The results indicate that autumn is a very good fishing season for light falling-net in offshore waters. Besides,
S.oualaniensis and larger tuna species, small tuna species and round scad should be further studied.