Territoriality

Question 1

Why form a territory?

Answer 1

Exclusive access to food, mates, nesting sites, cover etc

Question 2

Why are territories not just home ranges?

Answer 2

They require patrolling and defending

Question 3

Name some groups that form territories

Answer 3

Individuals, pairs, family groups and occasionally unrelated groups

Question 4

How are the borders of territories defined?

Answer 4

Presence of landmarks reduce fighting and allow more pairs to establish a territory

Question 5

What is economic defendability?

Answer 5

Economic defendability states that defence of a resource have costs, such as energy expenditure or risk of injury, as well as benefits of priority access to the resource. Territorial behaviour arises when benefits are greater than the costs.

Question 6

What is an example of economic defendability?

Answer 6

Golden-winged sunbirds
Measure metabolic costs of foraging, perching or defending
When nectar levels are low, birds that defend can gain more from the extra time they don’t need to spend foraging
If nectar levels are high, excluding nectar thieves does not pay for itself…
At high levels, nectar intake is limited by handling time, not availability

Question 7

What determines fight outcome?

Answer 7

Resource holding potential

Question 8

What determines resource holding potential?

Answer 8

Residency
Body size
Resource valuation
Motivation
Energy reserves
Prior experience

Question 9

What is an evolutionarily stable strategy?

Answer 9

“A strategy which, if all the members of a population adopt it, no mutant strategy can invade”