Regulation of Populations

1
Regulation of Populations

• Other processes besides carrying capacity
  regulate population growth and size.
• Can you name some of the processes?
• Regulation is usually density-dependent
• negative feedback

2
Competition for Resources
Negative feedback high density of individuals
competing for limited nutrients reduces
reproductive output.
3
Territoriality
Negative feedback high density and limited space
for territories means some individuals will not
reproduce.
4
Health

• High density brings individuals into close
  contact
• Rapid transmission of disease
• Chronic Wasting Disease in deer and elk

5
Predation
Negative feedback abundant predators decreases
density of prey.
6
Population Dynamics
Populations regulated by complex interaction of
density-dependent and density-independent
processes.
7
Community Ecology

• Study of communities of organisms and their
  interactions with the environment
• Species richness number of species present
• Species diversity number of species and relative
  abundance (proportion) of each species
• What types of interspecific interactions could
  potentially be found in a community?

8
Competition

• Competition occurs when individuals use the same
  limited resource
• Intraspecific competition
• competition within species
• Interspecific competition
• competition between species
• Competitive exclusion
• Species that is better competitor will outcompete
  and exclude another species from area

9
Resource Partitioning
Species divide resources. Reduces competition,
allows more species to coexist in community.
10
Ecological Niche

• The total use by a species of the biotic and
  abiotic resources in the environment
• Unique to each species
• Realized niche smaller than fundamental niche