Factors of Extinction

1. Factors of Extinction Why are some species more or less prone to extinction?

2. Niche • Species who have a specialized niche are more prone to extinction.

3. Source: http://www.destination360.com/north-america/us/alaska/alaska-whale-watching.php Source: http://www.biojobblog.com/tags/panda/ Source: http://www.koalas.org/koala-australia.html Specialization • Over specialization of feeding • Over specialization of habitat

4. Source: http://www.pbase.com/johncarol/image/73692533 Source: http://www.srgc.org.uk/bulblog/log2007/100107/log.html Low Reproductive Rate • r versus K strategists

5. Source: http://www.nytimes.com/2006/07/16/world/europe/16tuna.html Source: http://www.awf.org/section/wildlife/elephants Source: http://animals.nationalgeographic.com/animals/mammals/wolf.html Predators and Man • Man preying on species • Hunting • Trade • Species preying on man or livestock • Large bodied animals are hunted for sport

6. Trophic level • Higher up in the food chains are more susceptible Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/POD/i/indian-tiger-india-512815-ga.jpg

7. Interspecific Competition • Nesting sites • Food • Breeding • Habitat Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/POD/a/axis-deer-512754-ga.jpg

8. Behavior • Migratory Patterns • Fixed • Flexible • Both habitats are needed • Barriers to the path Source: http://www.ag.gov.au/www/agd/rwpattach.nsf/VAP/(454DFAFE2D6830FB1D0597823A67B5D6)~red+crabs+migration.JPG/$file/red+crabs+migration.JPG Source: http://www.sciencedaily.com/releases/2008/01/080108083008.htm

9. Distribution • Narrow geographical range is more dangerous. Examples: Golden lion tamarin, birds on islands… Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/POD/p/polar-bear-cubs-492324-ga.jpg Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/POD/g/grassland-kangaroos-76934-ga.jpg

10. Overall Numbers • The lower the numbers the more prone • Low population densities • Few populations of the species Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/POD/b/baby-gorilla-gabon-651797-ga.jpg Source: http://animals.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/animals/images/primary/platypus.jpg

11. Strategies for Success • Generalists over specialists • Diversity • Of ecosystems • Complexity of food webs • Inertia/Constancy • Resilience Source: http://www.staringspestandrodentcontrol.com/files/images/American-cockroach.preview.jpg

12. Categories and Criteria from: The IUCN Red List of Threatened Species

13. Conservation Status • Extinct (EX) – there is no reasonable doubt that the last individual has died • Extinct in the Wild (EW) – Known only to survive in cultivation, in captivity, or as a naturalized population well outside the past range

14. Threatened • Critically Endangered (CR) – Facing an extremely high risk of extinction in the wild • Endangered (EN) – Facing a very high risk of extinction in the wild • Vulnerable (VU) – Facing a high risk of extinction in the wild

15. Criteria for CR, EN and VU • Reduction of population size by W% over 10 years or 3 generations • Size of geographic range • Population size of mature individuals less than X with continued decline of Y% over 10 years or 3 generations • Population size of mature individuals less than Z • Quantitative analysis showing the probability of extinction in the wild

16. Conservation Status • Near Threatened (NT) – Close the qualifying for a threatened category in the near future • Least Concern (LC) – Widespread abundant taxa are included in this category

17. Conservation Status • Data Deficient (DD) - there is inadequate information to make an assessment of the risk of extinction • Not Evaluated (NE) – has not been evaluated against criterion