Environmental Engineering Reference
In-Depth Information
Chapter 13
Species Competition and Predation
Peter Chesson
Glossary
Apparent competition
The tendency for an increase in the density of a species to
increase the impact of a natural enemy on that same
species or other species.
Competition
The tendency for an increase in the density of a species to
have a negative effect on the survival or reproduction of
individuals of the same species or of other species by reduc-
ing resource abundance, reducing access to resources, or by
direct harm of one individual organism on another
associated with resource acquisition.
Density dependence
The tendency for an increase in the density of a species to
have a negative effect on the survival or reproduction of
individuals of the same or different species. As used in this
essay, the species in question are in the same guild. Com-
petition and apparent competition are special cases of
density dependence.
Feedback loop
A chain of species interactions from one member of
a guild, through other species, back to a species in that
same guild. Feedback loops transmit density dependence.
Guild
A group of species potentially co-occurring in the same
locality and having similar ecology in the sense of
depending on the same or similar resources, often seeking
