L19 - Mass Migration and Importation of Alien Species

Question 1

What is an invasive species?

Answer 1

A non-indigenous species whose introduction does or is likely to cause economic or environmental harm or harm to human health.

Question 2

What is the societal relevance?

Answer 2

• Major cause of biodiversity loss (not often full extinction, but extirpation)
• Cause large amounts of physical changes
• Industrial impacts
• Aesthetics
• Property values
  
  • $137B US/yr to USA
  • $1.28 Trillion worldwide since 1970

Question 3

What are the historical implications?

Answer 3

South America…
- Continental-sized “island”
- Lots of extinction after invasion
- Lots of speciation during isolation
South America was an island for much of Cenozoic
- Then 3 MYA, movements of large continental plates caused the joining

Question 4

Why are there monkeys in South America?

Answer 4

• Came long after the Pangea broke up

Question 5

What are the steps of a biological/ecological invasion?

Answer 5

1. Source location of species
2. Transport/introduction
3. Establishment: environmental characteristics required for a species to persist.
4. Spread
5. Impact

Question 6

What are the two types of pathways of invasion?

Answer 6

1. Transportation related
   - Air, land, freshwater and marine (trains, planes, ships (ballast water))
   - Containers and packing materials (wood, soil, seaweed)
   - Mail, internet
   - Travellers (baggage, animals/garden shows, humans as disease vectors)
2. Commerce in living organisms
   - Foodstuff
   - Non-food animals (research, zoos, fur, museums)
   - Plant trade

Question 7

What is the species distribution model (SDM)?

Answer 7

• To predict how species will move in different areas.
• SDM uses environmental variables as correlates of biological invasions (usually establishments)
• Modelling the spread of organisms across the area - humans play a crucial role in the secondary spread.

Question 8

What is argued as the most effective management options of invasive species? What is another management strategy?

Answer 8

• Prevention (most effective and most cost-effective)
  
  • Particularly at the before the species in pathway is transported and released alive
• Eradication
  
  • Successful eradication is dependent on the area infested and the reaction time

Question 9

What is the phytosanitary policy - ISPM15?

Answer 9

• Treat wood-packing material (e.g., pallets)
• Reduce introduction of wood-boring pests

Question 10

What are some mechanisms of Integrated Pest Management?

Answer 10

• Manual (traps)
• Chemical (herbicides, pesticides)
• Biological (introduction of natural predators/parasites)
• Gene drive (Target Malaria), mRNA