A Model for Predicting the Distribution of Albacore Within Environmental Temperature Gradients

Abstract

The albacore, Thunnus alalunga, is a high seas pelagic tuna (Scombridae) whose distribution frequently seems governed by temperature. Tunas probably behaviorly thermoregulate using kineses. One method for explaining this process is a klinokinetic avoidance model. Actual telemetry data on albacore were analyzed and then used to construct such a model. Among the responses examined were instantaneous speed, angle of turn and temperature preference. A computer program was constructed to generate surface temperature isopleths using actual oceanographic data in the area of the tracked fish. Correlation analyses were performed on the data to determine the effect of the environment on fish movement. Two models were implemented: (1) a klinokinetic avoidance model and (2) a model using actual regression equations from the correlation analyses. The klinokinetic avoidance model proved to be the more successful of the two.