Nonnative Species In Aquatic Ecosystems Answers

All of the following are true of the Zebra mussels found in the Great Lakes EXCEPT: a. Zebra mussels are having are having a negative impact on the native population of mussels in the region. b. They were unintentionally introduced to the Great Lakes by humans. c. Zebra mussels have caused a great deal of environmental damage to the area. d. People of the Great Lake region are benefitting from the economic advantages of having zebra mussels in the region. Please select the best answer from the choices provided

Which of the following is an example of mechanical control of nonnative species?a.pesticidesb.herbicidesc.net barriersd.inspections

Hull fouling is a(n) _______ introduction of nonnative species.a.unintentionalb.intentionalc.unimportantd.land-based

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

Nonnative species are only introduced unintentionally.

Which of the following is not true about nonnative species?a.They can have positive impacts on an ecosystem.b.They can have negative impacts on an ecosystem.c.They can be introduced within their natural range.d.A nonnative species can be an invasive species.

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

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.

All nonnative species in an ecosystem are considered invasive species.

Nonnative species disrupt the natural variability of an ecosystem.