The Influence of Environmental Variables on the Distribution and Abundance of Three Elasmobranchs in Tomales Bay, California

  title={The Influence of Environmental Variables on the Distribution and Abundance of Three Elasmobranchs in Tomales Bay, California},
  author={Todd E. Hopkins and Joseph J. Jr. Cech},
  journal={Environmental Biology of Fishes},
We tested the hypothesis that temperature, salinity, and dissolved oxygen affect elasmobranch distribution and abundance in Tomales Bay, California, with monthly longline samples over a 20 month period. We used a Poisson regression under generalized least squares and found that temperature and salinity were the most important factors determining the distribution and abundance of the three most common elasmobranch species, bat ray, Myliobatis californica, leopard shark, Triakis semifasciata, and… 

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