GALE CARROLL, PLATTSBURGH, NEW YORK: My name is Gale Carroll, from Plattsburgh, New York, and I want to ask CNN if all the coral reefs are dying.</s>ELLEN PRAGER, MARINE SCIENTIST: Research and surveys of the world's coral reefs do suggest that they are in decline or changing -- not so much that the reefs are dying, but we know that there are some human influences that are, in fact, negatively impacting coral reefs: overfishing, pollution from sewage and sediment, and global warming are all having a negative impact on our coral reefs. There is a natural variability in coral reefs that we don't quite understand yet. So right now, we're trying to fix the things that we can, that is stopping pollution, stop boat groundings, and things like that that we know harm coral reefs, and study how resilient reefs are, to see if they could come back from things like global warming and other factors. I wouldn't say that the world's coral reefs are dying, but they are seriously threatened, and we need to take some protective measures, like create marine sanctuaries and study reefs, to protect them and hopefully prevent them from dying in the future.
Ask CNN: Are All the Coral Reefs Dying?