Giving-up diversity (GUDiv): top-down effects of foraging decisions on
local, landscape and regional biodiversity of resources
Abstract
Foraging by consumers has direct effects on the community of their
resource species, and may serve as a biotic filtering mechanism of
diversity. Determinants of foraging behaviour may thus have cascading
effects on abundance, diversity, and functional trait composition of the
resource community. Here we propose giving-up diversity (GUDiv) as a
novel concept and simple measure to quantify community effects of
foraging at multiple spatial diversity scales. GUDiv provides a
framework linking theories of adaptive foraging behaviour with community
ecology. In experimental resource landscapes we showcase effects of
patch residency of foraging wild rodents on α-GUDiv, ß-GUDiv and γ-
GUDiv, and on functional trait composition of resources. Using GUDiv
allows for prediction-based investigation of cascading indirect
predation effects (ecology of fear) across multiple trophic levels, of
feedbacks between functional trait composition of resource and consumer
communities, and of effects of inter-individual differences among
foragers on the diversity of resource communities.