Habitat, Territory & Migration Flashcards
habitat selection is a process that operates at the level of the _____
individual
describe Ideal Free Distribution
- based on game theory
predicts how animals distribute themselves across habitats of varying quality when competing for resources like food or mates
~ assumes they are free to choose habitats
~ assumes all individuals are ideal & have same competitive ability
patch quality decreasing with increasing _____ _____
competitor density
~ due to resource depletion
3 types of patterns of distribution
- random
- regular (uniform)
- clumped
resource holding potential & it influences what (2)
ability of a territorial animal to win a fight (maintain territory)
influences:
- dispersal
- migration
resource defense theory
animals will defend a resource only if the benefits of defence outweigh the costs
~ not all individuals are equal some are better at defence than others (those who can and will benefit the most)
explain lower & upper threshold, and middle area in resource defense curve
lower = resources too scattered and too few competitors
~ no defence
middle area = defending gives a fitness benefit (worth it)
~ aggressive defence behaviour
upper = too many competitors/ constant fights/ patrolling too costly
~ no defence
arbitrary contest resolution hypothesis
- resident always wins
- evolutionary stable strategy (ESS)
- both sides avoid fights
resource holding potential hypothesis
- conflicts usually determined by physical advantages
~ size
~ strength
Payoff asymmetry hypothesis
not all individuals value the same territory equally
~ territory owners value their area more than intruders and so owners fight harder
dear enemy effect
once territorial neighbours recognize eachother they don’t fight as often, save energy
describe dispersal
permanent move from birthplace to elsewhere
- costly
- avoid inbreeding
describe migration and what it’s influenced by
leaving areas for an extended period of time and returning
influenced by:
resource holding potential
migration routes depend on
- fitness of individual
- distance
- wind
- predators
- stop over locations
costs & benefits of migration
costs:
- energy and resources needed
- mortality
benefits:
- longer day length enable more feeding time
- better conditions for growth of young
- fewer predators
- access to food and water on breeding grounds
