Flashcards in Lecture 6-animal movements Deck (17)
3 types of animal movements
Local- relatively small scale within a home range or territory
Migration- movement back and forth on a regular basis (eg. seasonal)
Dispersal- Movement from the place of birth to the site of reproduction (one way)
Difference between homerange and territory?
Homerange is an area that an indivudual uses normally during some specified time period.
A territory is a subset of homerange that the individual, pair, pack actively defends against competition to maintain exculsive ownership of the resource.
What are some characteristics of a territory?
-Permanent or seasonal
-Used to defend food, mating or breeding sites
How is optimal territory size determined?
When the Difference between the benefits and costs of defending the territory is maximized
What is dispersal?
One-way movement associated with immigration and emmigration
What is migration?
Occurs repeatedly for a single individual as a "round trip". involves moving to a new area as an adaption to temporal changes in environmental factors
7 types of migration:
breeding range and non breeding range do not overlap- neotropical migrant birds
North/South migration (seasonality) -Many birds, mule deer
Up/Down movement (elevation) -American dipper, Bighorn sheep
Between sites that provide resources ( unpredictable) Barren ground caribou
Breeding sites, safer from predators, bighorn sheep, rocky mountain elk
Requires extreme changes in prey (varies in frequency, distance , and numbers migrating) Snowy owl, grey owl
Breeding and non-breeding ranges can overlap for some individuals in the pop (Red tailed hawks, golden eagles)
What makes managing migratory species difficult?
1. More than one area to protect
2. Uncertainty about which sites are most important to suvival/reproduction
3. Crossing political borders, changes in laws and mgmt
Why is dispersal important? what determines who is dispersing?
- Age (younger) or Sex (birds= F>M, Mammals=M>F)