Professor Rogers: "Human impacts on the oceans are damaging vital food resources and functions that feedback to climate change and move us further towards unpredictable and potentially catastrophic changes to the environment, biodiversity and human society. This is of deep concern to me and the majority of scientists who study the ocean and should be treated as a global emergency of utmost urgency".
Big Threats:
Climate Change, Over-fishing, Habitat Destruction, (Oil, etc.) Extraction, Pollution & Alien Species Introduction.
"In Brief: Most, if not all, of the five global mass extinctions in Earth's history carry the fingerprints of the main symptoms of global carbon perturbations (global warming, ocean acidification and anoxia or lack of oxygen; e.g. Veron, 2008).
It is these three factors — the 'deadly trio' — which are present in the ocean today. In fact, the current carbon perturbation is unprecedented in the Earth's history because of the high rate and speed of change. Acidification is occurring faster than in the past 55 million years, and with the added man-made stressors of overfishing and pollution, undermining ocean resilience.
.... Continued releases and slow breakdown rates mean that legacy chemical pollution ( such as from DDT) remains a major concern. However, concerns have been raised recently over a wide range of novel chemicals now being found in marine ecosystems or suspected to be harmful to marine life. High-profile examples include brominated flame retardants, fluorinated compounds, pharmaceuticals and synthetic musks used in detergents and personal care products.
Some of these chemicals have been located recently in the Canadian Arctic seas, and some are known to be endocrine disrupters or can damage immune systems. Marine litter and plastics are also of major concern, and there is evidence that certain plastics can transport other harmful chemicals in the marine environment.
…..Scientists at the IPSO meeting agreed that overfishing is exerting an intolerable pressure on ecosystems already under attack by the effects of acidification and warming, and other largely man-made ocean problems. A recent study showed that 63% of the assessed fish stocks worldwide are over-exploited or depleted and over half of them require further reduction of fishing, in order to recover.
The near extinction of a fish called Chinese bahaba (Bahaba taipingensis) is one of the many examples that highlight how overfishing threatens marine biodiversity. It has taken less than seventy years for this giant fish to become critically endangered after it was first described by scientists in the 1930s."
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