An Assessment to Relationships between the Yellowfin Tuna and the Spotted Dolphin in Eastern Pacific Ocean (EPO) from 1998 to 2006

Database belong to the Programa Nacional de Aprovechamiento del Atún y Protección de los Delfines (PNAAPD) from México. The area covers from latitude 5 to 20 N and longitude 90 to 125 W, Eastern Pacific Ocean (EPO), for 1998, 2001, 2002, 2005 and 2006 includes date, geographical position, sea surface temperature, tuna’s catch, yellowfin tuna’s size and dolphin’s number. 5 degress squares of latitude and longitude, each year were made. Yellowfin tuna number was normally distributed (KSd = 0.02, P > 0.20). The problem to solve is the relationship of the spotted dolphin and yellowfin tuna, that may analyze in the background of a non linear generalized model. Considering the array of latitude and longitude over the years that the abundance of yellowfin tuna is a dependent variable and the spotted dolphin abundance is the covariance continuous variable, the interaction and covariance, indicates a significant contribution to variability. The tuna abundance index does produce significative differences in latitude and longitude. Considering the dolphin as a dependent variable and the yellowfin tuna as a covariance continuous variable, the dolphin abundance index produced significative differences in latitude and longitude.Base de datos pertenecen al Programa Nacional de Aprovechamiento del Atún y Protección de los Delfines (PNAAPD) de México. El área abarca desde la latitud 5 a 20 N y longitud 90 a 125 W, Océano Pacífico Oriental (OEP), para 1998, 2001, 2002, 2005 y 2006 incluye la fecha, la posición geográfica, la temperatura de la superficie del mar, la captura de atún, Número de delfín 5 cuadrados de degress de latitud y longitud, cada año se hicieron. El número de atún aleta amarilla fue distribuido normalmente (KSd = 0.02, P> 0.20). El problema a resolver es la relación del delfín manchado y el atún aleta amarilla, que puede analizar en el fondo de un modelo generalizado no lineal. Teniendo en cuenta la variedad de latitud y longitud a lo largo de los años, la abundancia de atún aleta amarilla es una variable dependiente y la abundancia de delfines manchada es la variable continua de covarianza, la interacción y la covarianza, indica una contribución significativa a la variabilidad. El índice de abundancia de atún produce diferencias significativas en latitud y longitud. Considerando el delfín como variable dependiente y el atún aleta amarilla como variable continua de covarianza, el índice de abundancia de delfines produjo diferencias significativas de latitud y longitud

Vertical habitat utilization by tagged yellowfin tuna (Thunnus albacares) released in the Revillagigedo Archipelago Biosphere Reserve, Mexico

A description of vertical habitat use by yellowfin tuna, Thunnus albacares, captured and released with archival tags in the Revillagigedo Archipelago Biosphere Reserve, Mexico, during the 2006–2011 period is given. An analysis was made of internal and ambient temperatures, depth, and time of day registered in 68 archival tags recovered from tuna caught mostly in sets associated with dolphins by Mexican purse-seine vessels. Tuna were classified into 3 age groups (I, II, and III) for analyses. Vertical movements were analyzed by dividing the water column into 10 depth strata. The 3 age groups remained the longest in the uppermost stratum (0–25 m), and their presence began to diminish in subsequent strata, with some occasional visits at >500-m depths. In the >500 m stratum, age group III was the one with the longest time investment with 45 min on average. Presence at different depths throughout the day showed significant differences among age groups (Wald’s test expressed as χ2, P < 0.05). The physiological adaptation of yellowfin tuna to maintain minimal changes in its internal temperature at different depths gives it the advantage to expand its food search to deep zones where temperature oscillates around 5 ºC