1. Invasion species
Sapozhnikova Elena

2. Invasions can be caused by:
Invasions are processes of the penetration of alien species into ecosystems located outside their natural areas and their impact to the native communities.
Invasions can be caused by:
natural migrations of organisms by climatic changes and fluctuations of population abundance
introduction of the economically useful organisms
accidental drift with ballast water, agricultural products etc

3. The types of invasion species influences on native species:
alien species can essentially change habitat of indigenous species
invasion species can become superior competitors, predators or pathogens for native species and promote their replace

4. G. fasciatus is successful invader from Lake Baikal.
1989
1989
1986
1986
1988
1988
1986
1986
1969
1977
1969
1973
1964
1968
1967

5. The main factors, which promoted replacement of Gammarus lacustris by Gmelinoides fasciatus in Lake Ladoga
G. fasciatus is superior competitor for food
G. fasciatus has shorter generation time and higher productivity
G. fasciatus has a higher ability to avoid the fish predation
Gmelinoides fasciatus
Gammarus lacustris

6. The ways of invasion prevention
careful studying of the influence of alien species on native species at all levels
toughening of the customs inspections
informing of the population about possible danger

7. Thank you for your attention!