Population Dynamics, Carrying Capacity, and Conservation Biology

1. Population Dynamics, Carrying Capacity, and Conservation Biology G. Tyler Miller, Jr.’s Environmental Science 10th Edition Chapter 8

2. Key Concepts • Environmental factors affecting populations • Role of predators in controlling populations • Reproductive patterns and species survival • Conservation biology • Human impacts on populations • Lessons about sustainable living

3. Sea Otters: Back from the Brink of Extinction? • Keystone species • Pollution effects • Importance of otters • Orcas Fig. 8-1, p. 160

4. Population Dynamics and Carrying Capacity • Population dynamics • Biotic potential (intrinsic rate of increase [r]) • Environmental resistance • Carrying capacity (K) • Minimum viable population (MVP) • Exponential and logistic population growth

5. Dispersion Patterns for Organisms Fig. 8-2 p. 161

6. Factors Affecting Population Size Fig. 8-3, p. 162

7. Exponential and Logistic Population Growth Fig. 8-4, p. 163

8. Logistic Growth of Sheep Population 2.0 1.5 Number of sheep (millions) 1.0 .5 1800 1825 1850 1875 1900 1925 Year Fig. 8-5, p. 163

9. When Population Size Exceeds Carrying Capacity • Overshoots • Reproductive time lag • Diebacks (crashes)

10. Exponential Growth, Overshoot and Population Crash of Reindeer 2,000 1,500 Number of reindeer 1,000 500 1910 1920 1930 1940 1950 Year Fig. 8-6, p. 164

11. Population Density Effects • Density-independent controls • Density-dependent controls

12. Natural Population Curves Fig. 8-7 p. 164

13. The Role of Predation in Controlling Population Size • Predator-prey cycles • Top-down control • Bottom-up control Fig. 8-8, p. 165

14. Reproductive Patterns and Survival • Asexual reproduction • Sexual reproduction • r-selected species • K-selected species Fig. 8-10 p. 167

15. Positions of r-selected and K-selected Species on Population Growth Curve Carrying capacity K K species; experience K selection Number of individuals r species; experience r selection Time Fig. 8-9, p. 166

16. r-Selected Species cockroach dandelion Many small offspring Little or no parental care and protection of offspring Early reproductive age Most offspring die before reaching reproductive age Small adults Adapted to unstable climate and environmental conditions High population growth rate (r) Population size fluctuates wildly above and below carrying capacity (K) Generalist niche Low ability to compete Early successional species Fig. 8-10a, p. 167

17. K-Selected Species elephant saguaro Fewer, larger offspring High parental care and protection of offspring Later reproductive age Most offspring survive to reproductive age Larger adults Adapted to stable climate and environmental conditions Lower population growth rate (r) Population size fairly stable and usually close to carrying capacity (K) Specialist niche High ability to compete Late successional species Figure 8-10b, p. 167

18. Survivorship Curves Age Fig.8-11, p. 167

19. Conservation Biology: Sustaining Wildlife Populations • What is conservation biology? • Which species are endangered? • How are ecosystems functioning? • How can ecosystems be sustained? • Principles of conservation biology • Aldo Leopold’s ethical principles • Bioinformatics

20. Human Impacts on Ecosystems • Habitat degradation and fragmentation • Ecosystem simplification (monocultures) • Wasting Earth’s primary productivity • Genetic resistance • Eliminating predators • Introducing nonnative species • Overharvesting renewable resources • Interfering with cycling and flows in ecosystems

21. Human Footprint on Earth’s Land Surface Fig. 8-12, p. 169

22. Learning Sustainability from Nature • Dependence on nature • Interdependence • Unpredictability See Connections p. 170 • Limited resources • Recycle wastes

23. Four Principles of Sustainability Solar Energy Population Control PRINCIPLES OF SUSTAINABILITY Nutrient Recycling Biodiversity Fig. 8-13, p. 170

24. Principles of Sustainability How Nature Works Lessons for Us Rely mostly on renewable solar energy. Prevent and reduce pollution and recycle and reuse resources. Preserve biodiversity by protecting ecosystem services and preventing premature extinction of species. Reduce births and wasteful resource use to prevent environmental overload and depletion and degradation of resources. Runs on renewable solar energy. Recycles nutrients and wastes. There is little waste in nature. Uses biodiversity to maintain itself and adapt to new environmental conditions. Controls a species' population size and resource use by interactions with its environment and other species. Solutions: Implications of the Principles of Sustainability Fig. 8-14, p. 171