Presentation is loading. Please wait.

Presentation is loading. Please wait.

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

Similar presentations


Presentation on theme: "Factors of Extinction Why are some species more or less prone to extinction?"— Presentation transcript:

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

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

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

4 Prey/Man Source: http://www.awf.org/section/wildlife/elephants Source: http://www.nytimes.com/2006/07/16/world/europe/16tuna.html Source: http://animals.nationalgeographic.com/animals/mammals/wolf.html Man preying on species Hunting Trade Species preying on man or livestock

5 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

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

7 Behavior Migratory Patterns Fixed Flexible Source: http://www.sciencedaily.com/releases/2008/01/080108083008.htm Source: http://www.ag.gov.au/www/agd/rwpattach.nsf/VAP/(454DFAFE2D6 830FB1D0597823A67B5D6)~red+crabs+migration.JPG/$file/red+cra bs+migration.JPG

8 Distribution The more limited the more prone Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/P OD/g/grassland-kangaroos-76934-ga.jpg Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Phot ography/Images/POD/p/polar-bear-cubs-492324-ga.jpg

9 Overall Numbers The lower the numbers the more prone Source: http://animals.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/animals/images/primary/pla typus.jpg Source: http://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFile s/Photography/Images/POD/b/baby-gorilla-gabon-651797-ga.jpg

10 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

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

12 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

13 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

14 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

15 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

16 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


Download ppt "Factors of Extinction Why are some species more or less prone to extinction?"

Similar presentations


Ads by Google