Saturday, January 15, 2011
Millions of dead fish in Chesapeake Bay blamed on limited habitat and cold water stress, wake up! Face the truth!
Authorities in Maryland are investigating the deaths of about 2 million fish in Chesapeake Bay they are blaming on cold water stress, over population "come on, overpopulation of our decimated fish stocks", and limited deep water habitat, natural causes. Yes on a much smaller scale it happneed twice before in 1976 and 1980 but there is nothing natural about it and it is getting worse. millions of dead fish in Chesapeake Bay
Yes there is growing limited habitat but there is nothing natural about it and we know it. We are destroying the ocean and our very basis of life on earth. One of the largest of the 400 or so ocean dead zones is in the Gulf of Mexico, near the mouth of the Mississippi.However, scientists now say that some of these areas, including those off the Northwest, apparently are linked to broader changes in ocean oxygen levels.The Pacific waters off Washington and Oregon face a double whammy as a result of ocean circulation. Growing low-oxygen zones in oceans worry scientists | McClatchy
In 2004 I was alarmed because there was 150 dead spots today there are 400. Commonly, ocean "dead zones" have been linked to agricultural runoff and other pollution coming down major rivers such as the Mississippi or the Columbia.
Scientists may have found the most devastating impact yet of human-caused global warming — a 40% decline in phytoplankton since 1950 linked to the rise in ocean sea surface temperatures. I happen to think it is largely due to man and our pollution though some may be natural but I doubt it. We’ve known for a while that we are poisoning the oceans and that human emissions of carbon dioxide, left unchecked, would likely have devastating consequences. We are all part of the whole.
“Phytoplankton are a critical part of our planetary life support system. They produce half of the oxygen we breathe, draw down surface CO2 and ultimately support all of our fishes said marine biologist Boris Worm of Canada’s Dalhousie University in Halifax, Nova Scotia. We say the ocean is critical to life but personally I had no idea how critical. I thought we were talking giving up fish for food not life itself. Somebody of consequence better wake up!
What a coincidence with those two kill offs being in the 70's mand 90's, look at this: In the 1970s, the Chesapeake Bay was discovered to contain one of the planet's first identified marine dead zones, where hypoxic waters were so depleted of oxygen they were unable to support life, resulting in massive fish kills. Today the bay's dead zones are estimated to kill 75,000 tons of bottom-dwelling clams and worms each year, weakening the base of the estuary's food chain and robbing the blue crab in particular of a primary food source. Crabs themselves are sometimes observed to amass on shore to escape pockets of oxygen-poor water, a behavior known as a "crab jubilee". Hypoxia results in part from large algal blooms, which are nourished by the runoff of farm and industrial waste throughout the watershed.
The runoff and pollution have many components that help contribute to the algal blooms which is mainly fed by phosphorus and nitrogen. This algae prevents sunlight from reaching the bottom of the bay while alive and deoxygenates the bay's water when it dies and rots. The erosion and runoff of sediment into the bay, exacerbated by devegetation, construction and the prevalence of pavement in urban and suburban areas, also blocks vital sunlight. The resulting loss of aquatic vegetation has depleted the habitat for much of the bay's animal life. Beds of eelgrass, the dominant variety in the southern bay, have shrunk by more than half there since the early 1970s. Overharvesting, pollution, sedimentation and disease has turned much of the bay's bottom into a muddy wasteland.
One particularly harmful source of toxicity is Pfiesteria piscicida, which can affect both fish and humans. Pfiesteria caused a small regional panic in the late 1990s when a series of large blooms started killing large numbers of fish while giving swimmers mysterious rashes, and nutrient runoff from chicken farms was blamed for the growth.[15Chesapeak Bay wikipedia