MEPS prepress abstract  -  doi: 10.3354/meps07402

ABSTRACT: Hutchinson’s niche concept is an interesting tool increasingly used in the context of global change. This concept is currently applied to many ecological issues ranging from global climate change, exotic species invasion to management of endangered species. For both the marine and terrestrial realms, there is a growing need to assess the breadth and compare the niche of species to forecast their capabilities to adapt to global change. In this paper, we describe simple non-parametric multivariate procedures that are derived from a method originally used in climatology (1) to evaluate the breadth of the ecological niche of a species and (2) to examine whether the niches are significantly separated. We first applied the statistical procedures to a simple fictive example of three species separated by two environmental factors in order to describe the technique. Then, we used it to quantify and compare the ecological niche of two key-structural marine zooplankton copepod species (Calanus finmarchicus and C. helgolandicus) in the northern part of the North Atlantic Ocean utilising three environmental factors. The test demonstrates that the niches of both species are significantly separated and that the cold-water species has a niche larger than its warmer-water congeneric species.