threat to marine environment?

Question

What threat to the marine environment do you think has the most far-reaching consequences and why?

Answer 1

Global warming and associated changes in water temperature and ocean currents.

Example: Disruptions in ocean flows and changes in water temperatures caused the great Permian Extincition where 95% of all life went extinct.

Answer 2

I think the greatest threat to the marine environment is loss of biodiversity. This can happen when habitat is destroyed, as in coral reefs, salt marshes and mangrove swamps, through pollution, as in PCB's and other chemicals now found in fish, overfishing as in cod and haddock, and in other ways, such as the North Atlantic Right Whale. It is so endangered it might already be too late to save it. Every year, some die after collisions with ships or entanglement in fishing gear. On a smaller scale, the same thing is happening to manatees. Loss of diversity in the ocean, or in any other environment, has terrible consequences to humankind. It is difficult to predict these, but we are part of many food webs and will suffer when their members become extinct.

Answer 3

Overfishing has become a big issue. And off-shore drilling. There are a lot of threats to marine ecosystems and I think the biggest one in any given area might be different from place to place.