(Niche) (R)egion and Niche (Over)lap Metrics for
Multidimensional Ecological Niches
Description
This package uses a probabilistic method to calculate niche
regions and pairwise niche overlap using multidimensional niche indicator
data (e.g., stable isotopes, environmental variables, etc.). The niche
region is defined as the joint probability density function of the
multidimensional niche indicators at a user-defined probability alpha
(e.g., 95%). Uncertainty is accounted for in a Bayesian framework, and the
method can be extended to three or more indicator dimensions. It provides
directional estimates of niche overlap, accounts for species-specific
distributions in multivariate niche space, and produces unique and
consistent bivariate projections of the multivariate niche region. A
forthcoming article by Swanson et al. (Ecology, 2014) provides a detailed
description of the methodology. See the package vignette for a worked
example using fish stable isotope data.