%0 Journal Article
%T Environmental factors governing the distribution of the bottlenose (Tursiops truncatus) and the spotted dolphin (Stenella attenuata) in Golfo Dulce, South Pacific, off Costa Rica Factores ambientales que gobiernan la distribuci車n del delf赤n bufeo (Tursiops truncatus) y del delf赤n manchado (Stenella attenuata) en el Golfo Dulce, Pac赤fico sur de Costa Rica
%A Priscilla Cubero-Pardo
%J Investigaciones Marinas
%D 2007
%I 
%X This study, conducted from June 1996 to July 1997, was directed at determining the abiotic environmental factors governing the distribution of the bottlenose dolphin (Tursiops truncatus) and the pan-tropical spotted dolphin (Stenella attenuata) in Golfo Dulce. The spotted dolphin was associated with significantly deeper zones (t-test = -9.761; p < 0.001, n = 202) and with higher salinity (t-test = -3.538; p = 0.001; n = 202) than the bottlenose dolphin. The combination of environmental variables in the distribution areas of each species in Golfo Dulce was different, both spatially (F = 9.724, df = 12; p < 0.001) and seasonally (F = 9.735; df = 12; p < 0.001). Of all the environmental variables considered, Multiple Discriminant Analysis showed depth to be the main factor differenciating the distribution areas of the two species. The relationship between group size in each species, depth, and the location of their distribution areas in relation to the shore were analyzed and evidence regarding these aspects and variations in foraging strategies and prey composition was proposed to explain the differences found in their spatial distributions. Seasonal variations in salinity in the distribution areas and their inverse relationship with the time of the year were analyzed in relation to their possible combined effects on prey composition during different seasons in order to explain the seasonal variations in distribution patterns Este estudio, efectuado de junio 1996 ajulio 1997, fue dirigido a determiner factores ambientales abi 車ticos que regulan la distribuci車n del delf赤n bufeo (Tursiops truncatus) y el delf赤n manchado (Stenella attenuata) en el Golfo Dulce. El delf赤n manchado estuvo asociado a zonas significativamente m芍s profundas (t-test = -9,761; p < 0,001; n = 202) y con mayor salinidad (t-test = -3,538; p = 0,001, n = 202), comparadas con el delf赤n bufeo. La combinaci車n de variables ambientales en las 芍reas de distribuci車n de cada especie en el Golfo Dulce fue diferente tanto a nivel espacial (F = 9,724; df = 12; p < 0,001) como estacional (F = 9,735; df = 12; p < 0,001). Entre todas las variables ambientales consideradas, el An芍lisis M迆ltiple Discriminante (MDA) revel車 la profundidad como el factor con mayor diferencia entre las 芍reas de distribuci車n de las dos especies. Se analiz車 la relaci車n entre el tama o de grupo en cada especie, la profundidad y la ubicaci車n de sus 芍reas de distribuci車n respecto a la costa y fue propuesta evidencia entre esos aspectos y variaciones en estrategias de forrageo y composici車n de presas entre ambas especies, a fin
%K Costa Rica
%K cet芍ceos
%K factores ambientales
%K patrones de distribuci車n
%K delf赤n bufeo
%K delf赤n manchado
%K Costa Rica
%K cetaceans
%K environmental factors
%K distribution patterns
%K bottlenose dolphin
%K spotted dolphin
%U http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-71782007000200002