Predation pt. 1

Question 1

Predators exert strong influence on prey communities. What are the two effects?

Answer 1

Consumptive effects
non-consumptive effects

Question 2

What is a consumptive effect?

Answer 2

predators kill prey, consistently limiting the size of prey populations

Question 3

What is this an example of?

Researchers introduced non-native prey (spiders) to islands with and without predators (lizards). They they tracked spider population sizes.

Answer 3

consumptive effects

Question 4

Non consumptive effect

Answer 4

occurs when prey population size is limited because of fear of predation rather than predation itself. Fearful prey change habitats, behaviors, or timing of activity, thus wasting time/energy.

Question 5

Consumptive and non-consumptive effects can drive …..

Answer 5

cycles of predator and prey population sizes

Question 6

What is this an example of?

Both lynx and hare populations cycle every 9-10 years, with changes in lynx population size lagging about 2 years behind changes in hare population size.

Answer 6

Cycles of predator & prey populations

Question 7

High hare densities allow lynx densities to _____.

Answer 7

High hare densities allow lynx densities to INCREASE.

they now have more food available

Question 8

At high lynx densities, fear of predation reduces ____.

Answer 8

At high lynx densities, fear of predation reduces MATERNAL PARENTAL CARE TOWARDS OFFSPRING.

Question 9

After hare population declines, lynx populations _______.

Answer 9

After hare population declines, lynx populations DECLINE.

Question 10

Reduced lynx density causes ____.

Answer 10

Reduced lynx density causes HARE FEAR TO BE REDUCED AND REPRODUCTION RATES INCREASE.

Question 11

Whether the number of prey will increase or decrease at any moment in time is dependent on what?

Answer 11

on the number of predators, and vice versa.

Question 12

What is the predator isocline?

Answer 12

number of prey at which predator population size stays constant