Princ. Wildlife con. management week 7: Predation Effect

Define the risk of predation

the probability of being killed during some time period

Whats an encounter situation

whenever the distance separating prey and predator is less than whichever of their detection radii is greater

what is the major component of risk under behavioral control

predation risk trade-off where time spent vulnerable to attack

when does nonclassical diet selection occur

when the available food items differ in the degree to which handling and vigilance for predators are mutually exclusive

what is the most studied aspects of behavior under the risk of predation

Vigilance for predators

Evolutionary time

predation can cause natural selection (adaptations)

Ecological time

what happens during an individual's lifetime (behavioral decisions)

What are the 3 components of predation risk

1. α = encounter rate

2. d = prob. of death given an encounter

3. T = time spent vulnerable

Predation risk creates....

trade-offs

What is Handling Time

the amount of time an animal spends processing/eating a food item

What is Vigilance

watching or scanning for predators

What is a sentinel

an indiviudal that stops feeding and stands guard while others forage

What is Flight-initiation distance (FID)

the distance between predator and prey when the prey starts fleeing

What is mobbing

prey will attack or harass a predator

Can reproduction increase predation risk?

Yes

Actual Risk

the actual probability of being killed

Perceived Risk

what the animal thinks/assesses its risk to be

How does predation influence evolution

it selects for traits that help animals avoid predatorrs

Can prey behavior affect predation risk

yes, it can influence encounter, detection, escape, and exposure

What is the major trade-off during feeding

gaining food and energy vs. avoiding predators

How can habitat affect feeding decisions

animals may choose safer areas even if thy provide less food

How can predation risk change what an animal eats

animals may choose less profitable food that allows greater vigilance

What is the "many eyes" effect?

More group members provide more opportunities to detect predators.

What happens to FID when prey are farther from cover?

They generally flee sooner, producing a longer FID.

What is a margin of saftey

A buffer of time or distance that allows prey to reach safety before the predator.

How can predation risk affect respiration in fish?

Fish may change when and where they surface for air

What trade-off do air-breathing fish face?

Getting oxygen versus exposing themselves to predators.