> The graphic shows 79 species of plant lost. Anyone that's been to Hawaii knows there are far more than 79 introduced plant species.
But these two things are not directly comparable. On the one hand, you have species that have gone extinct -- no individuals of these species are known to grow in the wild anymore. This does not count species that are declining towards extinction. On the other hand, most lists of introduced plants for Hawaii only count species that are invasive. These are plants that not only grow and reproduce in Hawaii, but whose populations are increasing.
While species diversity as a whole in the Hawaiian islands is likely increasing, due to introduced species, the diversity at smaller spatial scales is likely decreasing as endemics become rarer.
> But these two things are not directly comparable
Correct. You simplified my comment nicely here (though I'm trying to find papers about smaller scales):
> While species diversity as a whole in the Hawaiian islands is likely increasing, due to introduced species, the diversity at smaller spatial scales is likely decreasing as endemics become rarer.
How do conservationists make value judgements in cases like this?
But these two things are not directly comparable. On the one hand, you have species that have gone extinct -- no individuals of these species are known to grow in the wild anymore. This does not count species that are declining towards extinction. On the other hand, most lists of introduced plants for Hawaii only count species that are invasive. These are plants that not only grow and reproduce in Hawaii, but whose populations are increasing.
While species diversity as a whole in the Hawaiian islands is likely increasing, due to introduced species, the diversity at smaller spatial scales is likely decreasing as endemics become rarer.