chapter 14: habitat selection, territory and migration Flashcards
habitat choice
choosing a place to live in
What are the main factors/resources that drive animals to choose particular habitats?
- shelter, food, enviornmental condition, mates
Ideal Free Distribution (IFD) model of habitat choice suggests.
individuals are free to settle in whatever habitat provides them with the highest fitness
What are the two main assumptions and major predictions the IFD model makes?
- animals are free to move unhindered by others
- animals can tell which habitats have more recources
- predicts first individuals to arrive should settle in habitat with the most recources
What is the equilibrium distribution point?
individuals will do equally well in either habitat
What is the resource Matching Rule, what does it predict?
predicts individuals should distribute themselves according to amount of recources in habitat
Understand what the equation R1/N1 = R2/N2 represents and what each variable
means.
individuals/ habitat is proportional to the amount of recources in that habitat
- R = amount of recources in habitat 1/2
- N = number of settled individuals in habitat 1/2
What is the ultimate goal of animals as they try to distribute themselves in a particular
habitat patch?
individuals should get equal distribution based on the recources in the habitats
What is the Ideal Despotic Distribution Model? How is it different from the IFD model?
modified version of IFD, habitat choice may be constrained by territorial behavior of already established individuals
What are other factors that individuals might consider when choosing habitats?
choosing certain habitats that are less prone to parasites and/or diseases, conspecific
cueing, etc.).
Understand the results of the study by Kiesecker and Skelly 2000 looking at how frogs
decide where to lay their eggs in order to avoid diseases/parasites.
…
What is territoriality? What are the benefits and costs of owning a territory?
occumation and defence of a particular area
- can provide owner with access to food, mates, and safe shelters
costs:
- must defend it
As the size of a territory increases, what else increases?
the costs increase
As the benefits of being territorial increases, what else increases?
if a territory is high quality providing many benefits, territory size can increase
If you have two territories and one has greater benefits than the other, which of these
territories will have a larger optimal territory size? Why?
*OPTIMAL territory size will be greater on territories that have fewer resources. ((need to have bigger territory size to get amount of resources u need bc there’s less available on lower quality habitat so u have to go longer distances to get more))
If you own a territory when would it be beneficial to allow other individuals to
temporarily share your territory? When would it not be beneficial?
when the cost to defend is too high it would not beneficial when the territory owner could’ve defended the territoy alone
satellite
intruder that does not own their own territory and wanders around others’ territories
Understand the study by Davies and Houston (1981). What did they find? Under what
context do territory owners tolerate satellites in the pied wagtail? How are their findings
related to byproduct mutualism (discussed in chapter 10)?
designed a _cost-benefit model_to help predict when owners should tolerate satellites
- Cost: Satellites will _take some food_from the territory
- Benefits
-satellites can help _defend territory__from other intruders
-satellites don’t know which areas have already been foraged (potentially allows owner to get more food)
**If there’s lots of food, owners should allow satellites to stay on their territory –> _byproduct mutualism___ (only way u get something is by helping)
*Their results matched predictions
What is one way an animal can learn which territory is best that was discussed in
lecture? What is conspecific cueing? Understand the anole study by Stamps (1986)
looking at this concept and what they found.
conspecific cuing: individuals choose their territory based on what others have chosen
What is migration? Understand it can be both latitudinal or elevational.
obligatory migration
HAVE TO move
irruptive migration
only migrate when conditions are poor
nomadism
moving from one place to another
What are the costs and benefits of migration especially compared to individuals that are
residents of tropical or temperate regions (at least for songbirds)?
How is nomadism different from obligatory migration? When do nomads decide to
leave?
What is piloting?
What is Zugunruhe? Emlen funnels?
Read through the article by Sudo and Tsukamoto (2015) on eel migration (in week 14
module). Be familiar with this study, what was done and what was found. Be familiar
with the questions and answers in activity 11 regarding this study. You will only be asked
about main concepts, rather than specific details.
