Seasonal variability of copepods and cladocerans in Bahía de los Ángeles (Gulf of California) and importance of Acartia clausi as food for whale sharks
Bahía de los Ángeles is located on the Ba ja Californian coast of the Gulf of California, adjacent to Ballenas Channel. The bay receives a dynamic tidal influe nce from the channel but is protected by numerous islands. It is a highly productive bay that ha rbors a high diversity of species, so me of...
| Autores: | , , |
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| Tipo de documento: | artigo |
| Estado: | Versão publicada |
| Data de publicação: | 2012 |
| País: | México |
| Recursos: | Centro de Investigación Científica y de Educación Superior de Ensenada |
| Repositório: | Redalyc-CICESE |
| OAI Identifier: | oai:redalyc.org:48023242002 |
| Acesso em linha: | https://www.redalyc.org/articulo.oa?id=48023242002 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Ciencias de la Tierra copepods Zooplankton cladocerans Acartia clausi Rhincodon typus |
| Resumo: | Bahía de los Ángeles is located on the Ba ja Californian coast of the Gulf of California, adjacent to Ballenas Channel. The bay receives a dynamic tidal influe nce from the channel but is protected by numerous islands. It is a highly productive bay that ha rbors a high diversity of species, so me of them protected such as the whale shark ( Rhincodon typus ). This study describes the seasonal variability of major zooplankton taxa and copepod and cladoceran species between May 2003 and October 2004. Copepods were dominant during winter and spring (83–99% of the zooplankton abundance), experiencing a dram atic decrease in autumn 2003 (37–66%) and summer 2004 (25–45%) . Cladocerans were the second most abundant group, represented by Pseudevadne tergestina and Penilia avirostris . The former species occurred year-round with low abundance in winter, wherea s the latter occurred only in summer a nd autumn. Other holozooplankton taxa cont ributed with less than 15% of the abundance in mo st of the samples, while merozooplankton c ontributed less than 8%, though in October o f 2003 and 2004 there was a remarkable abundance of echi noderms and other larvae cont rasting with their shortage in other seasons. In wint er 2004, temperate-subtropical copepod species dominated, such as Calanus pacificus and Acartia tonsa . The high abundance of copepods during spring obeyed to Acartia clausi (median = 28,034 ind m –3 ); however, the maximal zoopla nkton abundance (40,468 ind m –3 , 99.5% copepods) came from a sample collected south of Punta Aren a, where two whale sharks were observed fo raging. The shift in species composition d uring summer coincides with the predominance of easterly winds descri bed in the literature inducing a reversed circulation and a prob able transport of tropical species into the ba y during summer and autumn ( Centropages furcatus , Subeucalanus subcrassus , Acrocalanus longicornis , Tem o ra discaudata , and Corycaeus amazonicus ). |
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