1. POPULATION-LEVEL EFFECTS OF PREDATION

2. I. THE ROLE OF PREY DENSITY
A. Functional Response of Predators

3. I. THE ROLE OF PREY DENSITY
B. Numerical Response of Predators

4. I. THE ROLE OF PREY DENSITY
C. Total Response of Predators

5. II. DO MAMMALIAN PREDATORS REGULATE PREY POPULATIONS?
A. Predators of Waterfowl

6. II. DO MAMMALIAN PREDATORS REGULATE PREY POPULATIONS?
A. Predators of Waterfowl

7. II. DO MAMMALIAN PREDATORS REGULATE PREY POPULATIONS?

8. II. DO MAMMALIAN PREDATORS REGULATE PREY POPULATIONS?
B. Wolves and Ungulates
Declining caribou, moose, Dall sheep populations in Yukon
Experimental reduction of wolves over 5 years
Photo © Stephen Loring

9. II. DO MAMMALIAN PREDATORS REGULATE PREY POPULATIONS?
B. Wolves and Ungulates
Declining caribou, moose, Dall sheep populations in Yukon
Experimental reduction of wolves over 5 yrs
Wolf predation was
reducing recruitment of caribou & moose calves
reducing adult survival of moose

10. II. DO MAMMALIAN PREDATORS REGULATE PREY POPULATIONS?
C. Weasels
and voles in western USA
and voles in Russian crop ricks

11. II. DO MAMMALIAN PREDATORS REGULATE PREY POPULATIONS?
D. Overview

12. III. INTERACTION OF PREDATION AND COMPETITION
A. Lynx and Hares
During peak hare year:

13. III. INTERACTION OF PREDATION AND COMPETITION
B. Wildebeest and Lions-Hyenas
1. Predation-sensitive food hypothesis (PSFH)
2. Predator regulation hypothesis (PRH)
3. Surplus prey hypothesis (SPH)

14. III. INTERACTION OF PREDATION AND COMPETITION

15. IV. INDIRECT EFFECTS OF PREDATORS ON PREY
Effect of one species on another is mediated through a third

16. IV. INDIRECT EFFECTS OF PREDATORS ON PREY
Example: Iberian lynx
Egyptian mongoose
European rabbit
Rabbits preyed upon: fold increase in absence of lynx
Rabbit density: 2-4 fold lower in areas without lynx

17. V. THE CONCEPT OF COMPENSATORY EFFECTS
Compensatory Mortality
Substitution of mortality agents

18. V. THE CONCEPT OF COMPENSATORY EFFECTS
Compensatory Mortality
Substitution of mortality agents
Example: deer in predator-removal area

19. V. THE CONCEPT OF COMPENSATORY EFFECTS
Compensatory Mortality
Substitution of mortality agents
Example: woodchucks in Pennsylvania

20. V. THE CONCEPT OF COMPENSATORY EFFECTS
Other Types of Compensation
Example: woodchucks on a hunted site
increased survival of juveniles
reduced emigration of juveniles
increased fertility of yearling females