EXOTIC SPECIES Chapter 1.12

An introduced or non-native species. This species is living outside its native range and has arrived by human activity, either deliberate or accidental.

- the function or position (j0b) of an organism or population within an ecosystem. What the organism eats, what eats it, when it breeds, when it is most active and other roles in the ecosystem. -the particular area within a habitat occupied by an organism.

The introduced species; maintains itself in a limited range of habitats. The species does not disturb the ecosystem because it occupies an empty niche. spreads and affects others in the ecosystem. This threatens native biodiversity. becomes dominant and alters or upsets the whole ecosystem. affects several ecosystems and threatens biodiversity in each ecosystem.

Killer Bees African “killer bees” were introduced in Brazil in 1957 to increase the honey production. They out-competed and displaced the natural populations of bees and caused a decline in honey production! These bees are aggressive and will swarm and attack animals they feel threatened by. 150 people have died from “killer bee” attacks.

Discovered in 1990’s in Lake Erie Brought in by ships visiting from the Caspian Sea This mussel found lots of food and spread quickly through the Great Lakes. Attached to any hard object and blocked water intake pipes choking hydroelectric plants and cut off freshwater supplies for industry. Is now a permanent part of the Great Lakes food web.

Zebra mussels; compete with the native pearly mussels. provide food for ducks and bird Provides shelter for snails, insects, small crustaceans and water mites their larvae are also a good food source Eat algae allowing other aquatic plants to thrive Remove pollutants from the Great Lakes Water is 60% clearer than before the zebra mussels These toxins are then passed on to predators and can be toxic to animals further up the food chain.

Gobi Fish Found in the Welland Canal in Likely came from a ship that had visited the Black Sea Feed on zebra mussels Feed on the eggs of native species such as walleye, perch and small mouth bass

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Snakeheads are native to Africa and Asia. Snakeheads were once a large part of an aquarium fish industry and in some cultures considered a food delicacy. They arrive in local waters by people who abandon them. They are an aggressive fish which outcompetes native species. These fish can move overland from lake to lake.

Read pages 40  44 Construct a chart and list the positive and negative effects of the introduction of the zebra mussel into the Great Lakes. Copy the food web which contains the zebra mussel.