In this lesson we’ll be learning about how humans are harming our oceans through pollution, global warming and over fishing. But, don’t despair! We’ll also examine solutions to these problems to help preserve our oceans for generations to come.
What Threatens Our Oceans?
Picture setting sail on a cruise in the Pacific Ocean. Off to see beautiful, tropical islands, you’re excited to start your vacation. But, as you look down into the water, it’s not the turquoise paradise you had imagined. In the Pacific Ocean, millions of pieces of microplastics, tiny pieces of plastic from discarded trash, float in the water.
These plastic pieces, along with larger pieces of plastic and other trash make up garbage patches that drift between the coast of California and Japan. Garbage patches not only pollute the ocean but also kill sea birds, seals and other marine life. Today, we’re going to look at this and other threats to our oceans, and then we will also look at some solutions.
Unfortunately, garbage is only one threat to our oceans.
Today, we’re going to look at three common threats to oceans: pollution, global warming, and fishing.
Plastic is especially harmful to ocean life because it doesn’t degrade readily like paper products do. Plastics can take hundreds of years to decompose, allowing them to drift around our oceans without decay. Plastic products look like food to sea life below. Sea animals that mistakenly consume the plastic can’t digest it, causing clogs in their digestive system and eventually death. Other times, air-breathing animals, like sea turtles, get caught in plastic products and can’t reach the surface, causing them to drown.
Plastics aren’t the only way humans are polluting our oceans. Oil spills have disastrous affects on marine life and the coasts nearby. In 2010, one of the largest oil spills in the history of the United States occurred in the Gulf of Mexico. Over 3 million barrels of oil poured into the ocean after an explosion on the Deepwater Horizon oilrig. The oil not only polluted the ocean waters and the coral reefs beneath it, but also destroyed delicate estuary ecosystems on shore.
Although we might think of atmospheric pollution as a separate problem, the toxic pollutants we release into our air also affect our oceans.
Carbon dioxide is a major contributor to global warming, an increase in global temperatures. Global warming is causing the melting of polar ice caps and warming of our oceans.Although the change in ocean temperature may be small, the consequences can be disastrous to some of our most productive ecosystems. Coral reefs are home to the greatest marine biodiversity on Earth. These ecosystems are extremely delicate, and even slight changes in temperature can cause coral to die in a process called coral bleaching.
When coral dies, the animals and plants it supports also die. The Great Barrier Reef in Australia is currently undergoing a mass bleaching event that started in 2014, one of the worst bleaching events in history.
With the growing awareness of the health problems associated with eating red meat, many people are turning to the ocean for their next meal. However, like industrial agriculture, fishing poses many threats to our ecosystems. Fisheries are collapsing world wide, with over 70% of our fisheries being fully exploited to completely collapsed. The overfishing of large predators like tuna, sea bass, and grouper removes keystone species that regulate the population of other fish in the area, leading to population crashes.But, it isn’t just the species we actively catch that are in danger. Bycatch is any species caught during fishing that aren’t intended for sale.
In 2005, the NOAA (National Oceanic and Atmospheric Administration) estimated that 17% of fish catches in the United States were discarded as bycatch. Bycatch kills marine mammals, sharks, sea turtles and other important species needed to keep our marine ecosystems in balance.
The situation might be looking pretty grim at this point, but there are ways we can help protect our oceans.
First, to address the pollution in our oceans we must create less waste, reuse and recycle. The United States goes through billions of plastic bags each year, which ultimately end up in landfills and our oceans.
Choosing reusable bags, or opting for recyclable materials like paper is one way to reduce our waste. Recycle bottles and cans whenever possible and choose products with the least amount of packaging. All of those plastic containers that line our grocery store shelves ultimately end up in a landfill.
Choosing renewable energy sources like solar, wind or hydroelectric power can circumvent the problems caused by drilling for and burning fossil fuels.
These energy sources do not produce carbon dioxide, nor do they require the dangerous drilling that produced the Gulf oil spill in 2010. Many communities have alternative choices for energy available through your electricity provider.
The best way to help prevent overfishing is to switch to a vegetarian diet and get out of the seafood game.
If we could stop fishing entirely, our oceans would have time to recover. However, if you just can’t give up your weekly salmon dish, choose only sustainable seafood at your grocery store. These fisheries target fish lower on the food chain and only fish from areas that are not in collapse and are well managed. Sustainable seafood also includes farmed seafood from aquaculture farms that minimize pollution and damage to local ecosystems.
Humans are polluting our oceans with trash and microplastics that form large garbage patches, killing marine animals. Drilling for oil also leads to spills that harm both the ocean, seafloor and coastal environments.
Excessive use of fossil fuels is causing global warming, increasing the temperatures of our oceans, which leads to coral bleaching. Bycatch and overfishing are also plaguing our oceans. Recycling plastic, switching to renewable energy and changing our diets to decrease fishing are ways to halt these human threats to our oceans.