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Vol. 49 No. 2, 2010
Vertical Copepod Assemblages (0-2300 m) off Southern Brazil
Cristina de Oliveira Dias1,*, Adriana Valente de Araujo1, Rodolfo Paranhos2, and Sérgio Luiz Costa Bonecker1
1Universidade
Federal do Rio de Janeiro, Instituto de Biologia, Departamento de
Zoologia, Laboratório Integrado de Zooplâncton e Ictioplâncton, Prédio
do CCS, Bloco A, Cidade Universitária, Ilha do Fundão, Rio de Janeiro
21.941-590, Brazil
2Universidade Federal do Rio
de Janeiro, Instituto de Biologia, Departamento de Biologia
Marinha, Laboratório de Hidrobiologia, Prédio do CCS, Bloco A,
Cidade Universitária, Ilha do Fundão, Rio de Janeiro 21.941-590,
Brazil. E-mail:rodolfo@biologia.ufrj.br
Cristina de Oliveira Dias, Adriana Valente de Araujo, Rodolfo Paranhos, and Sérgio Luiz Costa Bonecker (2010)
The structure of copepod assemblages in the region of the Campos Basin
was studied for a 1 yr period. Zooplankton samples were obtained
in the 2002 wet season and 2003 dry season, by stratified vertical
hauls in 4 previously identified water masses: tropical water (TW),
South Atlantic central water (SACW), intermediate Antarctica water
(IAW), and North Atlantic deep water (NADW). Temperature and
salinity were determined. The copepod mean density did not
significantly differ (p < 0.05) between the northern and southern
stations in the 2 seasons, but significantly differed among the water
masses, and in each water mass in the 2 seasons, except for the
SACW. The highest mean density was found in the TW, and the
lowest in the NADW. Eighty-nine taxa of copepods, with 70
generally distributed species and 19 species exclusive to 1 or another
water mass were recorded in the 4 water masses. The copepod
assemblages of the Campos Basin showed tropical characteristics, and
were numerically dominated by epipelagic species: Clausocalanus furcatus, Farranula gracilis, and Oncaea venusta in TW; Pleuromamma abdominalis, Macrosetella gracilis, Oncaea venusta, and Clausocalanus furcatus in the SACW; Clausocalanus furcatus, Oncaea venusta, Triconia conifera, and Calanoides carinatus in the IAW; and Oncaea venusta, Oithona similis, Clausocalanus furcatus, Farranula gracilis, and Mecynocera clausi
in the NADW. Differences in the copepod community along the water
column were found. Differences in copepod compositions and
abundances were possibly a consequence of the influences of oceanic and
shelf waters, with contributions of deep-water species to the
upper-level water masses. Despite the oligotrophic nature of the
Brazil Current, the densities found were higher than those observed
along the Brazilian coast and in other tropical regions.
Key words: Zooplankton, Seasonal variations, Tropical coastal zone, Southeastern Brazil.
*Correspondence: Tel: 55-21-22601640. E-mail:crcldias@hotmail.com
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