Are all non-native species undesirable?

Question

This is for school&&will not have a "best" answer...thanks....

Answer 1

Yes, they fill in niches that should not be filled or fill in a niche that is already covered so the entire chain is messed up. A niche is an animal's role in an Ecosystem, which is basically the classification of the different environments to put it simply. This includes the desert or the rainforrest etc. One effect causes a ripple affect, and we don't want to be messing with how nature works. Look at the crayfish in Arizona. People who didn't want their fish just dumped them in rivers and so they took over. They filled in niches so that animals with the same niches died off and killed off other animals becuase they put a limiting factor that is not supposed to be there naturally. Now Arizona lakes and ponds are in horrible shape and the natural ecosystems are messed up.

It basically decreases biodiversity which is key in an ecosystem.

Answer 2

Horses are not native to North America. Didn't you ever want a horse?

Answer 3

no... for example: ladybugs are almost always beneficial

Answer 4

no they are not, for example the red tailed fox is not native to eastern north america, niether is the red tailed phesant, but they are both accepted species in north america, they are not harmfull and actually bring some benafits, for example the fox helps hunting small mamals that are often a nusance

Most of the time however non native species are harmfull, when they are harmful they are usually referd to as "invasive" instead of non-native, although that is still a correct term.

Answer 5

Somewhat.

By keeping species local, you help preserve biodiversity.

Answer 6

Not really. As long as the non-native species are not take over the habitat for the native species too soon to let the native to survive. Biological diversity is very important. And species move across boundaries happened many times in the natural history. A lot of invading species kill the native before the native evolve to adapt to the new environment.

Answer 7

non-native species do not have the same environmental restraints on them as native species and therefore often become invasive.  They can be pretty to look at, but they can easily become pests in the environment and crowd out native species.  Yes, they are always undesirable.