Research Technical Report

Multiscale habitat associations of deepwater demersal fishes off central California

Anderson, T.J. and M.M. Yoklavich (April 2007)

Fishery Bulletin 105(2):168-179

ABSTRACT

Fish-habitat associations were examined at three spatial scales in Monterey Bay, California, to determine how benthic habitats and landscape configuration have structured deepwater demersal fish assemblages. Fish counts and habitat variables were quantified by using observer and video data collected from a submersible. Fish responded to benthic habitats at scales ranging from cm's to km's. At broad-scales (km's), habitat strata classified from acoustic maps were a strong predictor of fish assemblage composition. At intermediate-scales (m's-100 m's), fish species were associated with specific substratum patch types. At fine-scales (<1 m), micro-habitat associations revealed differing degrees of microhabitat specificity, and for some species revealed niche separation within patches. The use of habitat characteristics in ecosystem-based management, particularly as a surrogate for species distributions, will depend on resolving fish-habitat associations and habitat complexity over multiple scales.