Invasion Ecology

Question 1

What are the determants of species success and dynamics?

Answer 1

• Variability in supply of recruits
• Oiceanographic influences of dispersal
• Larval behaviour
• Settlement process
• Variation in the receiving environment
• Anthropogenic transport pathways

Question 2

What is an exotic species?

Answer 2

“a species introduced to a region beyond the range in which it evolved (e.g. outside its native range)

Question 3

What is an invasive species?

Answer 3

An invasive species that becomes abundant or infuential in the habitats and bioregions it has invaded with adverse environmental, economic or ecological consequences

• invasive is relative (subjective term)
• Most introduced species are not invasive
• a species may be invasive in some regions but not others

Question 4

What is invasion ecology?

Answer 4

Case and consequence of biological invasions

• Examines the factors that influence estabilshment, spread and impact of introduced impact if introduced species
• a multidiscipplinary science that combines elements from various fields of study

Question 5

Why do we stud invasions?

Answer 5

• to understand how humans affect the distribution and abundance of other species
• invasions are altering ecosystems worldwide
• invasions are a major cause of extinctions
• invasions impact mulitple aspcts of society
• to precent or combat invsions

Question 6

What barriere determin species dispersal?

Answer 6

• Geographic barriers
• Physiological barriers
• Demographic resistance
• biotic resistance

Question 7

How do humans create new dispersal pathways?

Answer 7

• pollution
• habitat degradation/modification
• over harvesting
• loss of biodiversity

Question 8

How do invasions without human influence occur?

Answer 8

• rare on human time scales
• occur over small spatial scales
• require the removal of either
• a georgaphic barrier
• a physiological barrier

Question 9

What are 6 pathways created by humans that are responsible for invasions?

Answer 9

• Maritime transport pathway
• Mining and exploratoin pathway
• marine aquaculture pathway
• commvercial fishing pathway
• sport and recreation pathway
• research and education pathway

Question 10

Name four ship borne invasions of New Zealand

Answer 10

• Clubbed sea squirt (Styela clava)
• Underia pinnatafida
• Asian paddle crab (Charybdis japonica)
• Mediteranian fanworm (Sabella spallanzanii)