Nonnative Species In Aquatic Ecosystems Answers

Why does the aquarium trade contribute to the introduction of nonnative species?a.Exotic species can escape or be released into local ecosystems.b.Aquarium owners do not always understand how ecosystems interact.c.Nonnative fish are shipped worldwide for aquariums.d.All of the above

Why are cane toads in Australia considered an invasive species rather than simply nonnative?a.They are destructive to native species and have no natural predators.b.They reproduce more quickly than native species.c.They have venom glands.d.Large adult specimens are able to hunt snakes.

Introducing invasive species to an ecosystem results in an increase in biodiversity.

Cane toads are highly successful as an invasive species in Australia because there is only one species that is believed to be able to prey on them.

Why might it be beneficial to regulate what species of plants and animals people are allowed to own in particular environments?a.Some species might become invasive and destructive if they escaped.b.Some species may be dangerous to humans.c.Nonnative plants and animals should only be used for commercial purposes.d.There is no reason to restrict an individuals’ right to own plants or animals.

Which of the following is true concerning hull fouling from commercial shipping and recreational boating?a.It constitutes less than half of all nonnative species introductions.b.The revenue brought in from these industries is relatively small.c.It is difficult to prevent since ship hulls begin, conduct, and end voyages in water.d.It is best combated by chemical treatments.

Nonnative species disrupt the natural variability of an ecosystem.

Invasive species often unbalance the ecosystems into which they are introduced because _______.a.they did not co-evolve with the natural species and lack natural controls, like predatorsb.they breed quickly and have the potential to overpopulate an areac.they consume local resourcesd.none of the above

All nonnative species in an ecosystem are considered invasive species.

Why has the spread of the herbicide-resistant hydrilla through Florida’s waterways resulted in them no longer being navigable by most boats?a.Thy hydrilla has induced a drought that drained the waterways.b.The weed clogs propellers that boats use for propulsion.c.The sticky leaves of the weed hold boats in place.d.All of the above