Methods Of maintaining Biodiversity Flashcards
Conservation
Preservation and careful management of the environment and of natural resources
Two ways which scientists try to conserve biodiversity
In situ conservation = within the natural habitat
Ex situ conservation = out of the natural habitat
Extinct
No organisms of the species exists anywhere in the world
Extinct in the world
Organisms of the species only exist in captivity
Endangered
Species that is in danger of extinction
Vulnerable
A species that is considered likely to become endangered in the near future
In situ conservation
- Takes place inside an organisms natural habitat
- maintains not only the genetic diversity of species but also the evolutionary adaptations that enable a species to adapt continually to changing environmental conditions
- cheaper than ex situ conservation
- eg. Marine , aquatic, terrestrial land , nature reserves
National parks
- areas within the countries where the wildlife and environment are protected
- governments control these areas and pass legislation to ensure their protection
- several restrictions eg.
- human access is strictly controlled
- industrial activities such as agriculture and building are tightly regulated
- hunting is limited or completely prohibited
Marine parks
Protected areas of water that have been set up for the conservation of endangered marine ecosystems and species
Restrictions to prevent overfishing and pollution
Public engagement
- national and marine parks attract tourists each year which increases money and awareness for the conservation effort
- involving members of the local community can create jobs and acceptance of the parks
Active management techniques
- controlled grazing
- restricting human access
- controlling poaching
- feeding animals
- reintroduction of species
- culling or removal of invasive species
- halting succession
Halting succession
Natural process in which early colonising species are replaced over time until a stable mature population is achieved
Culling or removal of invasive species
- An invasive species is an organism that is not native to an area and has negative effects on the economy , environment , or health
- these organisms compete with native species for resources
Reintroduction of species
Adding species to areas that have become locally extinct or whose numbers have decreased significantly
Feeding animals
This technique can help to ensure more organisms survive to reproductive age
Controlling poaching
This includes Creating defences to prevent access , issuing fines , or more drastic steps such as removal of rhino horns
Restricting human access
Not allowing people to visit a beach during the seal reproductive season or by providing paths which must be followed to prevent plants being trampled
Controlled grazing
Only allowing livestock to graze a particular area of land for a certain period of time to allow species time to recover or keeping a controlled number of animals in a habitat to maintain it
Botanic gardens
- plant species can be grown successfully in botanic gardens
- here the species are actively managed to provide them with the best resources to grow , such as provision of soil nutrients, sufficient watering and the removal or prevention of pests
- 1500 botanic gardens worldwide holding 35000 plant species
Seed banks
- example of gene bank - store of genetic material
- seeds are carefully stored so that new plants may be grown in the future
- they are dried and stored at temperatures of -20°c to maintain their viability by slowing down the rate at which they lose their ability to germinate
- seed banks don’t work for all plants
- some seeds die when dries and frozen and sadly the seeds of most tropical rainforest trees fall into this category
Captive breeding programs
- produce offspring of species in a human- controlled environment
- run and managed by zoos and aquatic centres
- scientists aim to create a stable,healthy population of species
- captive breeding programmes provide the animals with shelter an abundant supply of nutritious food , absence of predators and veterinary treatment
- suitable breeding partners or semen can be imported from other zoos if not available within the zoos own population
Problems with maintains genetic diversity within captive breeding programmes
- small number of breeding partners are Available
- problems related to inbreeding can occur
How do you tackle these problems ?
- international catalogue is maintained detailing genealogical data on individuals
- mating can thus be arranged to ensure that genetic diversity is maximised
- artificial insemination
- embryo transfer
- long term cryogenic storage of embryos allow new genetic lines to be introduced without having to transport the adults to new locations
Reasons why some organisms may not be suitable for release in the wild
- Disease = loss of resistance to local disease in captive bred populations, new disease might exists in the wild to which captive animals have yet to develop resistance
- behaviour = some behaviour is innate but much has to be learned through copying or experience
- genetic races = the genetic make up of captive animals can become so different from the original population that the two populations cannot interbred
- habitat = the natural habitat must first be restored to allow captive populations to be reintroduced
- if only a small suitable habitat exists it is likely that there are already as many individuals as the habitat can support
- introduction of new individuals can lead to stress and tension as individuals fight for limited territory and resources such as food
