Sure I do, because the challenges the biological scientists face in identifying critical habitat for any species boil down to the availability of the empirical evidence and the data. And for a lot of these critters--we've got 450 designated so far--that empirical evidence hasn't been collected, so it's not part of the scientific arena yet.
Among the challenges that are faced in the determination of critical habitat is how best to obtain the required empirical evidence for the scientists to do their thing.