Spatial Variance of Capelin (Mallotus villosus) in Coastal Newfoundland Waters

摘要

33-43 Quantitative description of scale-dependent spatial variance provides clues to biological and physical mechanisms that generate patchiness. Patterns of spatial variance among mobile organisms differ from passive tracers of the surrounding fluid. Scale-dependent spatial variance of capelin (Mallotus villosus), a mobile pelagic fish species, was compared to sea surface temperature in 32 transects surveyed along the northwestern shore of Conception Bay. Capelin spatial variance was concentrated at single scales in some transects but when 30 transects were averaged, decreased with a slope of -0.40 from 10 km to 200 m scales. Spatial variance of sea surface temperature decreased with an average slope of -1.35. In the absence of strong horizontal temperature gradients, little evidence of anisotropic capelin distribution was observed in seven long- and cross-shore paired transects. Episodic scale dependence of capelin spatial variance suggests capelin-predator interactions are brief and occur over a wide range of spatial scales