Volumen 41 - Número 1: 87-95 | 2006
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Spatial and seasonal distribution of the hermit crab Pagurus exilis (Benedict, 1892) (Decapoda: Paguridae) in the southwestern coast of Brazil |
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Andrea L. Meireles1,2, Mariana Terossi1,2, Renata Biagi1 and Fernando L. Mantelatto1,2* |
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This study aimed to assess the spatial and seasonal distribution of the hermit crab Pagurus exilis in Caraguatatuba region, characterizing the abundance and distribution of individuals seasonally and bathymetrically. The relationship between groups of individuals and environmental factors (temperature, salinity, depth, amount of organic matter and texture of sediment) was checked. Sampling was carried out monthly from July 2001 to June 2003, at seven depths (5, 10, 15, 20, 25, 30 and 35 m), with a shrimp fishery boat equipped with two double-rigged trawling nets. A total of 1960 specimens of P. exilis were collected, including 1369 (69.9%) males, 304 (15.5%) non-ovigerous females and 287 (14.6%) ovigerous females. The individuals were distributed between 15 and 35 m and were absent at 5 m. A large amount of individuals was collected (40.6%) during winter and 57.8% of ovigerous females were also captured in the same period. Pagurus exilis tended to occur in association with a group of factors composed by: higher depths (15 to 35 m), higher salinity (34 to 37 psu), lower temperature (18 to 24ºC), and sediment of organic matter varying from 1 to 9%. |
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Key words: Crustacea, Anomura, population, environmental factors, abundance |
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1Laboratorio de Zooplancton, Instituto de Ciencias del Mar y Limnología,Universidad Nacional Autónoma de México. A. P. 70-305, 04510 México, D. F. México