Week 3 - Marine Introductions

Question 1

Introduced species

Answer 1

plants or animals that have been transported to the water beyond their natural range

Question 2

Invasive species

Answer 2

an introduced species that
has spread beyond the place of introduction
and caused damage to nearby species
Definitions

Question 3

Where are we seeing highest levels of introduction

Answer 3

A lot of these tend to be in temperate regions. This is because it is easier to adapt to these climates.

They are getting there via shipping routes

Question 4

What are the typical patterns of marine introductions?

Answer 4

Typically between temperate regions in both hemispheres

Between oceans, between countries

Question 5

Are we homogenizing the worlds marine biota by shipping?

Answer 5

In some areas yes

Question 6

What marine organisms are typically being introduced?

Answer 6

Is not restricted to one particular taxa.

Question 7

Are marine introductions an expanding threat?

Answer 7

Only a small proportion of transported species survive

Of these that survive only a small portion thrive.

However, some introduced species are superior competitors and/or voracious predators.

Question 8

What is the magnetite of the problem?

Answer 8

Worldwide

• 1000’s of introduced species
• industrialised countries affected more
• some areas >90% of biomass is exotic species
• responsible for collapsed fisheries, habitat phase shifts but no known extinctions.

Question 9

History of marine introductions

Answer 9

The move from sail to steam ships means we were getting to destinations quicker and a lot mire larvae could attached to the boats

Question 10

Why do we use genetic studies to study introduced species?

Answer 10

Genetic studies can be used to trace back to when and where species were introduced.

Question 11

What is an example of introduced disease?

Answer 11

Largest fish kill in Australian waters was an introduced disease from baitfish in WA

Question 12

What are modes of introduction?

Answer 12

Planned introduction and accidental introductions.

Question 13

What is an example of a planned introduction?

Answer 13

Pacific Oyster. Introduced from Japan. Deliberately released for aquaculture. Displaces native oyster and other invertebrates.

Question 14

What is are some major contributors to introduced species in Australia?

Answer 14

Hull Fouling. E.g 28 exotic species scraped off into Wellington Harbour from a ship.

Ballast water. 3000 non-native species per day transported from ships around the world

Question 15

Establishment and range expansion

Answer 15

Marine introductions are unpredictable, usually establish at wharfs and jetties, some populations establish and some don’t

Question 16

What is a measure we can take?

Answer 16

Prevention is the main hope. Ban on deliberate introductions, tight controls on fouling and hull cleaning, ongoing research, convention on ballast water dishcharge.