Development of movement models to assess the spatial dynamics of marine fish populations
Date of Award
Doctor of Philosophy (Ph.D.)
Marine Biology and Fisheries
First Committee Member
Jerald S. Ault, Committee Chair
Second Committee Member
Donald B. Olson, Committee Member
A simulation model is constructed which considers the population dynamics of bonefish, Albula vulpes, in a spatio-temporally articulated seascape using biological and physical environmental data describing Biscayne Bay. A sub-model of behavioral movement of bonefish in response to environmental cues is employed to describe the dynamic distribution of individual bonefish cohorts relative to features of their habitat. This sub-model is developed from a generalized framework based upon principles of kinesis behavior described herein. The function and performance of the movement model in acquisition of spatial resources for growth is analyzed with respect their subsequent influence on bonefish stock dynamics predicted in simulation. Two other movement behaviors are inserted in simulation for comparison of results: (1) random walk; and (2) a model of restricted-area search behavior. Simulations are designed to test the null hypothesis that population dynamics are not significantly influenced by the assumptions of the behavioral movement sub-model. The results of simulations are compared to elucidate the effect behavioral assumptions of movement and their practical application in simulation may have on stock dynamic simulations incorporating the spatial interactions of fish and habitat. It is demonstrated that implicit differences in a priori assumptions of behavioral movement can significantly affect stock dynamics predicted in simulation. The implications of simulation results on existing hypotheses of bonefish biology and stock dynamics are considered, which lead to recommendations for further coordinated efforts in both modeling and empirical studies. It is concluded that assumptions dictating movement behavior can significantly influence the population dynamics predicted in simulation, yet support of assumptions can be difficult to demonstrate from empirical data. It is submitted that a minimalist approach be adopted with respect to cognitive mechanisms in the design of behavioral movement models for incorporation into simulations of fish population dynamics.
Biology, Ecology; Biology, Oceanography; Agriculture, Fisheries and Aquaculture
Humston, Robert, "Development of movement models to assess the spatial dynamics of marine fish populations" (2001). Dissertations from ProQuest. 1777.