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When Is A Species Endangered And Where Should Conservation Efforts Be Placed. Sam Hopkins Biodiversity and Conservation Biology. An Optional Graphic can go here. What makes species vulnerable to extinction 1. Criteria taken from Cox (1997)
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When Is A Species Endangered And Where Should Conservation Efforts Be Placed Sam Hopkins Biodiversity and Conservation Biology An Optional Graphic can go here
What makes species vulnerable to extinction 1 • Criteria taken from Cox (1997) • Large species with a low reproductive potential • Species with a high economic value • Species at the end of a long food chain • Species restricted to local, insular habitats • Species that are specialised for habitats, breeding sites or food • Migratory species
When is a species endangered? • This is a matter of much discussion • Certain criteria are constructed by the organisations that need to categorise the extinction risk of species
When is a species endangered? The IUCN criteria 2 • IUCN stands for the International Union for the Conservation of Nature and Natural resources • They state that the extinction rate is 1,000 to 10,000 times higher than what it should be • They have 9 categories • Extinct • Extinct in the wild • Critically endangered • Endangered • Vulnerable • Near threatened • Least concern • Data deficient • Not evaluated
When is a species endangered?The CITES criteria 3 • CITES stands for The Convention on International Trade in Endangered Species of Wild Fauna and Flora • Signed by 169 countries • Species are placed into 3 appendices • Species threatened with extinction • Species not threatened but controlled to stop then becoming threatened • Species protected by one country and has asked CITES to control trade
Is it our duty to conserve? 1 • This is a personal question • Today's society generally has a pragmatic- utilitarian ethic. This means that human success is important and technology will answer any future problems when resources run low. It sees humans and a few animals (pets, whales, dolphins etc.) as primarily important and everything else of secondary importance • At the other end of the scale is the ecocentric ethic where the interests of humans and non-humans are treated equally on some kind of scale, where the lowest end of the scale is everything's right to exist to the highest end which is some kind of satisfaction • Is it also our duty to preserve things for future generations?
Is it our duty to conserve? 4 • Conservation costs money • Figures so far in America • Northern Spotted owl, $9.7 million • Grizzly bear, $5.9 million • Florida Panther, $4.1million • In the UK if all the plans for conservation were carried out it would cost 800,000 pounds per year for over 15 years • Is it better to put conservation areas to use in agriculture or housing?
What to conserve? • As you have seen from the past few lectures, the world is in an extinction crisis at the moment and it is not possible to conserve everything • The question is, what to conserve? • Do we conserve single large species that in turn will conserve large amounts of habitat for other species? • Do we conserve the genetically distinct animals such as the Tuatara? • Do we conserve ‘hotspots’ of land that will conserve the most numbers of species? • Do we leave species to go extinct as extinction is a natural process?
Do we conserve single large species that in turn will conserve large amounts of habitat for other species? • It is estimated that to conserve a viable elephant population for 1000 years it would take 1000 miles 2 of land 5 • In conserving this piece of land many other species would be conserved as well • However this may not always be the ideal land for conserving large numbers of endangered species if it is the elephants alone that are being concentrated on • On the positive side, people are more likely to give money to save a charismatic creature like an elephant than a snake or beetle
Do we conserve the genetically distinct animals such as the tuatara? • When the Tuatara was discovered it was thought that it was a lizard with an odd skull 6 • Now been placed in a group equal to the Squamata (lizards and snakes), Rhynchocephalia 7 • The Rhynchocephalia includes several extinct taxa and the two remaining species alive today • Was once widespread but now found only on small islands off New Zealand 8 • Has declined due to mammal introduction 8 • Is it important to keep these animals alive or should they have gone extinct years ago with all their relatives?
Do we conserve ‘hotspots’ of land that will conserve the most numbers of species? • One theory suggests that we should conserve hotspots of biodiversity • Identify areas with increased species richness, high numbers of endemic species and high numbers of rare species9
Do we conserve ‘hotspots’ of land that will conserve the most numbers of species?- argument for 10 • Areas that are conserved for their large species diversity will probably have a complex habitat allowing large amounts of diversity of other taxa to be conserved as well • Reyers et al. (2000) states that areas that are important to the conservation of one taxon will conserve high levels of diversity of other taxa 11
Do we conserve ‘hotspots’ of land that will conserve the most numbers of species?-argument against • However, often there is a low correlation between high species richness and high endemicity 9 • Hotspots for different species rarely overlap 11 • Eg. Reyers et al. (2000). Found that species richness hotspots for vertebrates and invertebrates are not the same10 • Hotspots may miss a species vital to conservation10 • Examples of species that are endemic to an area but not living in a species rich area 9 • Pocket gopher (Pappogeomys zinseri) • Perote ground squirrel
Do we leave species to go extinct as extinction is a natural process? • The number of species that have become extinct through time is almost equal to the number of originations of species 12 • Darwin saw extinction as a process of natural selection 12 • This is more a question of how humans see themselves fitting into nature • Are humans part of nature and therefore everything we do is also natural? • Or are we above nature and it is ours to do what we want with
Conclusions • This is a difficult topic to draw conclusions from • There are many different aspects that need contemplating and answering and it is a personal viewpoint • The general public’s view is often different from the scientific community’s view • As an answer as to what to conserve, Ceballos et al (1998) suggest a scale of priority where highest efforts are placed in conserving endangered species followed by non-endangered species with a small distribution with the lowest efforts being given to species that survive well with humans 9 • They do not state how a species is considered endangered and this approach needs much research to establish what is at risk
References Cox, G. W. (1997) Conservation biology. Pp 287-296 IUCN. An IUCN overview. [cited 2006 Jul 10] Available from: www.iucn.org/en/about CITES. What is CITES [cited 2006 Jul 10] Available from: www.CITES.org/eng/disc/what.shtml Spellerberg, I. F. (1996)Conserving biological diversity. In Conservation Biology. Pp 25-31 Armbruster, P. and Lande, R. (1993) A population viability analysis for African Elephants (Loxodonta africana): How big should reserve be? Conservation Biology 7: 602-610 Bogert, C. M. (1953). The Tuatara: Why is it a lone survivor? The Scientific Monthly76: 163-170 Pough et al. (2001) Herpetology 2nd Ed. Cree et al. (1995). Reproduction of a rare New Zealand reptile, the Tuatara Sphenodon punctatus, on rat free and rat inhabited islands. Conservation Biology 9: 373-383 Ceballos, G. et al. (1998). Assessing conservation priorities in mega diverse Mexico: Mammalian diversity, endemicity and endangerment. Ecological Applications 8: 8-17 Reyers, et al. (2000). Complementarity as a biodiversity indicator strategy. Proceeding: Biological Sciences267: 507-513 Dobson et al. (1997) Geographic distribution of endangered species in the United States. Science 275: 550-553 Raup, D. M. (1994). The Role of Extinction in Evolution. Proceedings of the National Academy of Sciences 91: 6758-6763