2. Conservation Of Biodiversity - Threats: Introduced Species Flashcards
What is the problem with introduced species?
The community of species naturally found in an area will be well adapted to its abiotic and biotic surroundings.
If a species is introduced, it may have adaptions that give it a greater chance of survival than the indigenous species which may then decline or die out.
Many species introductions have had catastrophic effects in the populations of indigenous species. Populations in isolated areas, such as islands, have been very seriously affected: they often have evolved from a small number of original colonising species and may not be adapted to survive new threats, such as mammal predators.
What are 2 examples of introduced competitors?
- The grey squirrel ..
What is the problem with introduced predators?
The introduction of predators has reduced the populations of many wildlife species, especially in areas where indigenous species are not adapted to survive in the presence of predators.
What are 2 examples of introduced predators?
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Give 2 examples of introduced pathogens into the UK and what the impact was
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What is the problem with species that hybridise?
If an introduced species is very closely related to an indigenous species then cross-breeding may produce fertile hybrids. The natural gene-pool will be changed by the introduction of genes it would not naturally contain.
Give 2 examples of species that hybridise
- The red deer is indigenous to the UK but is threatened by hybridisation with the introduced Sika deer
- The wildcat population in Scotland is threatened by hybridisation with domestic cats
Give 2 examples of the loss of species that control abiotic factors
- African forest elephants create clearings and water-holes that many other species rely on for water
- Beavers build dams, creating small lakes which are colonised by many aquatic species
If these species are lost then many other species may decline.
