TY - JOUR
T1 - Tidal influences on fish distributions on tropical eastern Pacific rocky shores (Colombia)
AU - Castellanos-Galindo, G.
AU - Krumme, U.
AU - Willis, Trevor J
PY - 2010
Y1 - 2010
N2 - On coasts with high tidal ranges, fishes regularly establish linkages between subtidal and intertidal habitats via tidal movements, such that the home range incorporates habitat that is only intermittently available. To examine the responses of shallow-water reef fish assemblages to tidal water level changes in a macrotidal area of the tropical eastern Pacific, daytime underwater visual fish surveys were carried out in intertidal and subtidal zones at different tidal stages in Utría National Park, Colombia. Labridae and Pomacentridae were the most abundant families, but species within these families changed between intertidal and subtidal zones. Of 106 species, >70% used the rocky intertidal zone. Benthic opportunistic reef species comprised ca. 85% of the intertidal migrant species, whereas the remaining 15% corresponded to ubiquitous reef and pelagic species. Little variation in subtidal and intertidal fish assemblages was observed between spring and neap tides, but there were large changes detected over the tidal cycle that were attributed to species-specific use of the intertidal zone at high tide. Intertidal fish assemblages comprised a defined subset of species that differed significantly from those of subtidal areas. Rocky intertidal habitats are used only haphazardly by most reef fishes, but a few common species shifted more than 90% of their population into intertidal habitats during high tide, indicating that for those taxa, intertidal habitats provide important foraging opportunities. This may introduce a significant source of local-scale bias to density estimates of subtidal reef fishes, and reef fish monitoring programmes should specifically factor tidal state as a controlling influence in macrotidal areas.
AB - On coasts with high tidal ranges, fishes regularly establish linkages between subtidal and intertidal habitats via tidal movements, such that the home range incorporates habitat that is only intermittently available. To examine the responses of shallow-water reef fish assemblages to tidal water level changes in a macrotidal area of the tropical eastern Pacific, daytime underwater visual fish surveys were carried out in intertidal and subtidal zones at different tidal stages in Utría National Park, Colombia. Labridae and Pomacentridae were the most abundant families, but species within these families changed between intertidal and subtidal zones. Of 106 species, >70% used the rocky intertidal zone. Benthic opportunistic reef species comprised ca. 85% of the intertidal migrant species, whereas the remaining 15% corresponded to ubiquitous reef and pelagic species. Little variation in subtidal and intertidal fish assemblages was observed between spring and neap tides, but there were large changes detected over the tidal cycle that were attributed to species-specific use of the intertidal zone at high tide. Intertidal fish assemblages comprised a defined subset of species that differed significantly from those of subtidal areas. Rocky intertidal habitats are used only haphazardly by most reef fishes, but a few common species shifted more than 90% of their population into intertidal habitats during high tide, indicating that for those taxa, intertidal habitats provide important foraging opportunities. This may introduce a significant source of local-scale bias to density estimates of subtidal reef fishes, and reef fish monitoring programmes should specifically factor tidal state as a controlling influence in macrotidal areas.
U2 - 10.3354/meps08768
DO - 10.3354/meps08768
M3 - Article
SN - 0171-8630
VL - 416
SP - 241
EP - 254
JO - Marine Ecology Progress Series
JF - Marine Ecology Progress Series
ER -