Biotemas (Sep 2008)
The commercial fishing of sardines (Triportheus spp.) landed in the fishery market of Porto Velho, Rondônia (1990-2004): Yield and general profile
Abstract
The profile of sardine fishing, the Triportheus species, landed at the fishing market of Porto Velho (RO) between 1990 and 2004, was established by analyzing variations in the intra- and inter-annual yield as well as the length and general characteristics of the fishing. The annual production varied from 15,372 to 78,340kg (average = 33,482kg), totaling 5.46% of the overall production during the studied period. These variations can be related to the changes in the fishermen’s effort, as a reflex to searching for alternatives for fishing, or related to the level of the river, since the greatest annual yields were preceded by years of having more intense flooding. The monthly production varied from 0 to 21,456kg (average=2,876kg). Greater values of production were obtained in periods of lower hydrological levels (dry season) [r(Pearson)= -0.53. p<0.0001]. The average capture per fisherman/day between 2003 and 2004 was 9.27kg. Rivers were the main environment from which the captures took place, mainly from the Jamari, Machado and Novo Aripuanã rivers, that are tributaries of the Madeira River. The lengths of the fishes varied from 70 to 380mm and presented a bimodal pattern, suggesting the presence of more than one species within the captures.
