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National Geographic

National Geographic
Ocean overfishing is simply the taking of wildlife from the sea at rates too high for fished species to replace themselves. The earliest overfishing occurred in the early 1800s when humans, seeking blubber for lamp oil, decimated the whale population. Some fish that we eat, including Atlantic cod and herring and California's sardines, were also harvested to the brink of extinction by the mid-1900s. Highly disruptive to the food chain, these isolated, regional depletions became global and catastrophic by the late 20th century. When It Started Marine scientists know when widespread overfishing of the seas began. In the mid-20th century, international efforts to increase the availability and affordability of protein-rich foods led to concerted government efforts to increase fishing capacity. But by 1989, when about 90 million tons (metric tons) of catch were taken from the ocean, the industry had hit its high-water mark, and yields have declined or stagnated ever since. When It Will End Related:  Ocean Issues

Why is overfishing a global concern? The problem of Overfishing We all love to eat fish, don’t we? It is the best source of protein and very healthy food in many ways. We also know where fish comes from—our oceans. Many decades ago, our oceans were full of fishes but unfortunately, this is not the case today. Our world today faces many complex issues ranging from pollution, climate change, wars, food crises, waste, over-population… and of course over-fishing. These are all problems we have created for ourselves, often as a result of our selfish activities. Overfishing particularly is one issue that is often underrated. By the end of this lesson, we will know how catastrophic overfishing is and how we are heading down a steep slope to a global disaster if we do not act quickly enough.

The Dirty Truth About Plastic BPA, in turn, is becoming this year’s poster child for all our doubts and fears about the safety of plastic. New research highlighting the possible dangers of BPA has received tremendous media coverage. In mice, at least, BPA exposure at crucial stages of development induces observable changes (such as breast or prostate abnormalities) that last a lifetime. The research may be confusing to a layperson, yet some consensus has been reached: Last November a panel sponsored by the National Institutes of Health (NIH) determined that there was at least “some concern” about BPA’s effect on the fetal and infant brain. What is not known is whether infants and children under 6 are even more heavily exposed, since they have not yet been studied (for phthalates, Swan says, levels are definitely higher in children than in adults). To shift public understanding on this issue is staggeringly difficult, especially given that exposure to plastic is not a matter of individual lifestyle.

UC Davis School of Vet Med: Oiled Wildlife Care Network: What Happens During an Oil Spill Recovery and Transportation - When there is an oil spill, specially trained workers go out and collect oiled wildlife. They wear protective clothing that keeps the oil off of their skin. Once they collect the oiled animals, they stabilize, or make sure they are not in immediate danger, then transport them to a medical facility for care. Intake – When the oiled animals get to the medical facility they go through intake, which is a full physical exam, just like you get when you go to the doctor. Workers will check their temperature, how much they weigh, whether they look healthy, and how much oil is on them. Each animal gets a medical record, so that workers can keep track of how they are doing. Stabilization – After the oiled animals have gone through intake, they are stabilized. Cleaning – This is the step where the oiled animals are finally washed. Release – Once an animal is completely waterproof, healthy, and is acting and eating normally, then they can be released.

Marine problems: Pollution Seas of garbage Solid garbage also makes its way to the ocean. Plastic bags, balloons, glass bottles, shoes, packaging material – if not disposed of correctly, almost everything we throw away can reach the sea. Plastic garbage, which decomposes very slowly, is often mistaken for food by marine animals. High concentrations of plastic material, particularly plastic bags, have been found blocking the breathing passages and stomachs of many marine species, including whales, dolphins, seals, puffins, and turtles. This garbage can also come back to shore, where it pollutes beaches and other coastal habitats. Sewage disposal In many parts of the world, sewage flows untreated, or under-treated, into the ocean. This sewage can also lead to eutrophication. Toxic chemicals Almost every marine organism, from the tiniest plankton to whales and polar bears, is contaminated with man-made chemicals, such as pesticides and chemicals used in common consumer products.

OR&R's Marine Debris Program | Marine debris is everyone's problem. Oceans, Whales & Seafood. Help protect marine life | Greenpeace Half the oxygen we breathe comes from our oceans. One of our world’s most stunning features, they cover more than 70 percent of the planet, comprise 99 percent of its habitable space, and house the greatest diversity of major plant, animal, and microbial species, from the simplest to the mightiest on earth. Their importance to all life cannot be underestimated. Oceans regulate the climate, produce half of the earth’s breathable oxygen, and are a huge source of food. And because of some pretty careless industrial human activity, our oceans are in a lot of trouble right now. We’ve made significant progress to turn the tide towards ocean conservation, but a lot more needs to be done in a short time. Ensuring Sustainable Seafood The problems taxing the ocean are caused directly by what's available at the seafood counter. Spotlight on Tuna Tuna is one of the world's favorite fish. Our appetite for tuna is pushing several species of sharks, turtles, and tuna closer and closer to extinction.

What is Water Pollution for children What is water pollution? Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater), very often by human activities. Water pollution occur when pollutants (particles, chemicals or substances that make water contaminated) are discharged directly or indirectly into water bodies without enough treatment to get rid of harmful compounds. Pollutants get into water mainly by human causes or human factors. Water pollution can be a Point-source, Non Point-source, or Transboundary in nature (Click here to learn more). Water pollution is the second most imperative environmental concern along with air pollution. Any change or modification in the physical, chemical and biological properties of water that will have a detrimental consequence on living things, is water pollution. The water pollution problem Water covers over 70% of the Earth’s surface. Water pollution affects drinking water, rivers, lakes and oceans all over the world.

i think that this is good for telling how it started back in the day by i216 Apr 3

This site is really good for learning about the causes of overfishing. by i216 Apr 3

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