A new report warns that the state of the world's oceans is far worse than suspected, with marine species at an unprecedented risk of extinction.

The International Program on the State of the Ocean says in its report issued Monday that oceans are degenerating faster than anyone has predicted.

The report says the combination of stress factors affecting oceans is creating conditions linked to every previous major extinction of species in Earth's history. Because of the unprecedented speed of change, panelists say, the rate of deterioration is hard to assess. But they say the first steps to globally significant extinction may have begun with the rising threat to marine species such as reef-forming corals.

Marine scientists from around the world have gathered at Oxford University in Britain to review recent research by ocean experts. They say they have found firm evidence that the effects of climate change and other human impacts, such as over-fishing and pollution by run-off from farming fertilizers, have caused a dramatic decline in ocean health.

Program scientific director Alex Rogers described the findings as shocking. He said the situation demands unequivocal action at every level to prevent consequences for humankind for generations to come.