back to index ofchapters1. Give an example of how the algae shown in Figure 205.1 has had anaffect on a local industry?
The algae in Figure 205.1 was introduced into the southern oceans ofTasmania by an overseas ship, reproduced rapidly and now concentrates inlocal scallops and oysters. When people eat the seafood, the toxin producedby the algae makes them ill and gives the scallop an undeserved bad reputation.Fish shops then have difficulty selling scallops which then impacts on thewhole scallop fishing industry.
Alt. When people eat the seafood, the toxin produced by the algae makesthem ill and gives the scallop an undeserved bad reputation. Fish shopsthen have difficulty selling scallops which then impacts on the whole scallopfishing industry. The algae produces spores that live in soft silty seabedsfor many years and are a very hardy species and therefore pose a big problem.
2. How do sea stars eat their prey?
Sea stars eat other molluscs by wrapping their arms around their preyand pulling them apart (Figure .1). In large numbers, they can wipe outentire populations of molluscs in a matter of months.
3. List three introduced pests which are likely to be in your local marineenvironment.
Ans. Starfish, algae, seaweed.
4. What is ballast water and why is it dangerous?
Ans. Ballast water is therefore sea water taken on in overseas portsto balance large ships sailing to Australia and New Zealand with limitedcargo. Ballast water can pick up harmless animals or plants from one portwhich become a pest in another.
5. Describe two methods used to get rid of the crown of thorns starfish?
Ans. Injection or collection.
6. Once a marine pest is in a port, how can it spread to another?
Ans. By another ship taking on ballast.
7. What is drupella?
Ans. A marine snail.
8. When does a marine pest become a threat?
Ans. When population numbers increase, the animal is declared a marinepest and often attracts media attention.
9. How do sea stars kill their prey?
Ans. Sea stars eat other molluscs by wrapping their arms around theirprey and pulling them apart
10. What is a fouling organism?
Ans. When a boat is not moving, many organisms can become attached tothe hull of the boat below the waterline. These are called fouling organisms.
11. Give an example of how of introduced fish could devastate a localaquaculture industry.
Ans. Allowing live Canadian salmon into the country could introduce devastatingsalmon diseases to our aquaculture industry. Once introduced they wouldbe here forever, affecting all future generations.
1. Because our coastline is so large and because little is known aboutintroduced pests, the CSIRO is keen to establish a network around Australianfor collecting information and monitoring changes in our marine environment.
Schools would be ideal centres for continuous monitoring of local coastline.Send your information to:- CRIMP Handbook Information CSIRO Marine Lab,GPO Box 1538 Hobart 7001.
Suggestions:
Write to CRIMP
Email "Handbook Information" to crimp@ml.CSIRO.au or via theirweb address.
2. Schools close to ports used by ships depositing ballast water maybe able to investigate how much ballast is released and whether the shipsfollow Australia's voluntary guidelines for ships entering Australian waterfrom overseas ports.
These guidelines were produced by the Australian Quarantine and InspectionService (AQIS). You should be able to get a copy of the brochure outliningthese guidelines from your local AQIS centre.
Address for AQUIS is:
PR Section, AQUIS, GPO Box 858 Canberra 2601.
In addition there is a Ballast Water Unit with brochures and furtherinformation at the above address,
They also have a web page on:
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1. marine pest
2. country
3. Ballast water
4. pests
5. threat
6. attached
7. fouling
8. Barnacles