Approaches: Priority species conservation; hotspot approach; ecosystem based conservation
Priority species conservation
- Charismatic megafauna e.g. tigers, pandas, whales etc. - Gather public's attention. - Traditional approach.
- Almost always large vertebrates
- Often endangered.
- Population viability approach (PVA) - Assesses population persistence- chance of a population of a certain size surviving in the long-term. Population needs to be above a certain level.- Smallest population size that has the highest chance of persisting in the future. Need to consider efects of habitat loss, fragmentation, mortality raes, recruitment/birth rate, dispersal patterns, age and distribution of the population.
- Use this information to plan conservation strategies
Fishery managers use this same idea- determine maximum sustainable yield. When fishing is above the MSY- fish biomass in the sea decreases.
Ex-situ conservation e.g. captive breeding programmes- takes a lot of effort and investment. Carried out in zoos, botanical gardens, arboretums, aquariums, agricultural seed banks. Some captively bred species of trans-located individuals can be re-introduced to their natural habitat- but this can only occur if all the factors that caused the extinction in the first place is no longer a problem.
Benefits: Great for raising public awareness+money; umberella effect-may end up protecting other species also.
Limitations: Only protect a very limited number of species. Sometimes they are beyond help? Pandas? Fulflil any ecological role? Dosen't conserve ecosystem services +processes. Expensive.
Money Issues: Financial resources for conservation are limited. Human population pressures continue to grow along with a demand for resources. May have to prioritise efforts. What is the best approach for delivering ecosystem services- effective+efficient.
The Hotspot Approach
Know species are not uniformally distributed- extremes of high species richness = hotspots. Protecting these areas would protect a high number of species.
- Focus areas that have exceptional concentrations of endemic species under threat from habitat loss.
- Terrestrial hotspots=1.4% land surface- 45% plant species, 35% vertebrate species
- Marine hotspots=0.03% world's oceans- 35% coral reefs, over 58% restircted range species e.g. fish, corals, snails, lobsters,
Conservational International (NGO): Have identified various hotspots around the world- would need to focus on areas within these regions. e.g. entire of New Zealand and Madagscar are hotspots. But does this mean all the other areas don't need any protection? Likewise in marine hotspots- coral triangle, Indonesia, Caribbean, St Helens and ascension islands.
Benefits: Greatest conservation gain per unit area. Most hotspots are in developing countries- opportunity for development gains.
Limits: different taxa sometimes have different hotspots; species are dynamic- distributions are changing a lot; how are hotspots defined?- richness, endemics, threatened species? Ignores areas outside of hotspots- some of which may be important for ecosystem services.
The Ecosystem Approach
Reasoning= We need to conserve healthy, productive ecosystems for ethical reasons and for the services they provide to humankind. Important to protect all the different components of ecosystems to ensure functionality. Integral to this approach is to…