Lecture 18: Socioeconomic Impact

Question 1

Technological impacts?

Answer 1

• Brown tree snack causing damage to electrical supplies
• Rats destroying grain supplies and causing fires by biting electrical wires
• Invasive ants causing water loss via chewing through tubing, causing sugar plants to die off

Question 2

Why are technological systems vulnerable to invasive species impacts?

Answer 2

1. They represent areas of concentrated human activity
2. They impose artificial structure son the environment that may alter habitat to that may benefit the invaders
3. Their installation and maintenance commonly disturbs the resident community
4. They are often well connected with each other and the local environment promoting rapid invasion

Question 3

Fouling organisms impact?

Answer 3

• block pipes and cooling sytems
• impairs water treatment facilities and power plants
• fouling seawater and aquaculture facilities
• costly to try and fix
• zebra mussels, asiatic clams , green mussel , charru mussel, black striped mussel, dark false mussel

Question 4

What are the ecological characteristics of fouling organisms?

Answer 4

1. larval dispersal ability
   - bysal attachment to solid surfaces
   - small body size
   - early maturity
   - short life span
   - high fecundity
   - preference for cryptic shaded surfaces

Question 5

Why are water supply systems vulnerable?

Answer 5

• easy entrainment of planktonic larvae and juveniles by fouling organisms
• abundance of artificial surfaces and cryptic spaces
• no predators
• continuos replenishment of oxygen, food, larvae
• warm temp

Question 6

Discuss how invasive species can impact agriculture and aquaculture.

Answer 6

1. Tunicates in PEI
   - filter feeders, grows in dense clumps, overgrows mussels and oysters reducing their yield
2. Corn root worm
   - damages corn roots
   - found near airports
3. Degradation of farm land
   - leafy spurge
   - toxin capable of killing cattle if eaten in high quantity
   - reduces grazing areas and results in smaller sheep and cattle growth
4. Varroa mites and honeybees
   - parasites
   - drone larvae are attacked
   - carry deformed wing virus
5. Death of bats via white nose syndrome causing boom in insects which will lower crop yields

Question 7

Summarize technological impacts of invasive sp

Answer 7

1. actually a form of resource and interference competition
2. result from our attempt to monopolize aa resource
3. most impacts are difficult or impossible to predict
4. Illustrates interconnectedness of technology and environment

Question 8

Dutch elm disease

Answer 8

• fungus
• killed many elms in canada
• very costly

Question 9

Two main categories of economic impact?

Answer 9

1. Loss of potential economic output
2. The cost of combating invasions

** 1 is difficult to estimate bc most invasions are undocumented, most documented are poorly studied, precise economic costs are unavailable and there is not tandard way of assignment monetary values to ecosystem services

Question 10

Issue with control costs?

Answer 10

• chronic and substantial
• 100 million dollars each year to control Hydrila for ex
• lamprey in great lakes each year os costly

Question 11

Ex of indirect impacts?

Answer 11

1. leafy spurge
   - reduces value of land, directly impacts cattle
   - loss in recreation
   - many control costs
2. Golden apple snail
   - introduced as a food source to increase export income of rice
   - people didn’t like the case bc of slime
   - snail pop grew and spread through irrigation canals and consumed rice
   * costly

Question 12

Some introduced species can have economic benefit BUT sometimes these can be offset by another introduced species. Ex?

Answer 12

• exotic species cultivated in aquaculture often are vulnerable to pathogens
  2. varroa mites destroy honey bee hives
  3. most of the worlds food comes from a small number of crops which are cultivated beyond natural range
• *BUT most of the economic loss to crop is due to non indigenous pests and plant pathogens

Question 13

Trad bans?

Answer 13

• costly
  ex: potato wart fungus
• US banned all PEI imports
  lots of money lost

Question 14

Ecotourism ?

Answer 14

• invasive sp can destroy this
• ex rats and feral cats introduced to islands destroying native bird populations
• eradication is expensive

Question 15

What is biosecurity

Answer 15

• risk management that defends against biological threats to the economy , the environment and human health
  ex:
• exotic plants hogging water
• nuclear power failure due to mussel clogging
• new Zealand is ahead of the game…
  L> Biosecurity act which unifies all pest management legislation into one law, creating a central authority to deal with biological threats to agriculture, forestry and biodiversity