INVESTIGADORES
DELEVATI COLPO Karine
congresos y reuniones científicas
Título:
COMPARATIVE POPULATION STRUCTURE OF UCA VOCATOR (HERBST, 1804) FROM THREE SUBTROPICAL MANGROVES
Autor/es:
COLPO KARINE; NEGREIROS-FRANSOZO MARIA LUCIA
Lugar:
MAÓ - MENORCA - ESPAÑA
Reunión:
Congreso; 36th European Marine Biology Symposium - a marine science odyssey into the 21st Century.; 2001
Resumen:
The brachyuran crabs of the genus Uca, commonly known as fiddler crabs, are very abundant in Brazilian mangroves, playing an important role in the ecology of such ecossystems. In Southwestern of Atlantic Ocean, U. vocator occurs from Pernambuco to Santa Catarina, living in burrows digged in the sediment and feeding themselves on its organic matter. The population structure of U. vocator was investigated throughout a year period in the mangroves of Itapanhau (23°49´14" and 46°09´14"W), Indaia (23°24´51"S and 45°0Il´14"W) and Itamambuca (23°24´43" and 45°00'53"W) in Sao Paulo. Size, recruitment and sex-ratio were the analyzed aspects of U. vocator biology environmental features at each locality were determined by mangrove forest structure observation, texture and organic matter content of the sediment. Crabs were collected by effort capture sampling technique: two collectors during 15 min. All captured crabs were lected according to sex. Carapace width (CW) was measured with a caliper (0.01 mm). The sex-ratio favours males and apparently is caused by ecological and behavioral reasons. Fiddler crabs presented the following median sizes: 13.2 in Itapanhau, 14.2 in Indaia and 19.3 mm of CW in Itamambuca, with significative difference among them (Kruskal-Wallis, p<0,05). Indaia and Itamambuca mangroves presented characteristics of young and productive forest while Itapanhau showed features of a mature mangrove with a low productivity. Additionally, the later mangrove was subject to an oil spreading, which caused an environmental impact. In conclusion, fiddler crabs reach larger sizes, including size at onset of maturity in more productive areas, what may indicate that food availability is favouring the growth of U. vocator.