Here Are The Biggest Threats To Marine Wildlife Today

By Nathaniel Whelan on July 7 2020 in Environment

Whale Shark filter feeds in polluted ocean, ingesting plastic. Image credit: Rich Carey/Shutterstock.com
Whale Shark filter feeds in polluted ocean, ingesting plastic. Image credit: Rich Carey/Shutterstock.com
  • Industrial agriculture frequently uses chemicals that find their way into the ocean, posing a threat to the surrounding wildlife from the smallest shrimp to the biggest whales.
  • On average, over one million marine animals such as fish, turtles, and birds die every year because of plastic pollution.
  • Fishermen catch sharks only to cut off their fins and throw them half-alive back into the water; these fins are then sold for as much as $500 a pound and used in specialty dishes like soup.

Chemical-filled beached whales. Turtles stuck in plastic beer rings. Birds drenched in oil.

These images are evocative and upsetting, but it should come as no surprise that our bodies of water—particularly oceans—are at great risk. From global warming to tourism, there are many factors playing a role in the declining quality of aquatic life. And the truth is, all we have to do is look in the mirror to see who is responsible.

Below are ten of the biggest threats to marine wildlife today.

10. Global Warming

Polar bear on an ice floe. Image credit: Jan Martin Will/Shutterstock.com
Polar bear on an ice floe. Image credit: Jan Martin Will/Shutterstock.com

Global warming is one of the biggest threats to marine wildlife today. As the temperature rises, glaciers and other ice formations melt, causing the sea level to rise. During the past two decades, the water has risen 0.13 inches every year; that is twice the average speed of the previous eighty years before that. Higher sea levels cause flooding which destroys habitats. When this occurs, animals such as the ringed seal either die or have to find a new home. Moreover, warmer water causes coral bleaching and affects migration patterns. Global warming also leads to ocean acidification.

9. Acidification

Coral Bleaching under water Okinawa, Japan. Image credit: Buttchi 3 Sha Life/Shutterstock.com
Coral Bleaching under water Okinawa, Japan. Image credit: Buttchi 3 Sha Life/Shutterstock.com

Carbon dioxide (CO2) is produced from the burning of fossil fuels. Approximately thirty to forty percent of the CO2 humans release into the atmosphere dissolves into our global waters and forms carbonic acid. Over the past 200 years, the world’s oceans have become thirty percent more acidic, causing irreparable harm to the marine wildlife. For example, higher levels of acid prevent crustaceans from forming shells and mating properly. It also causes coral to die from lack of nutrients. Ocean acidification also impacts humans who depend on fish and other marine creatures for food.

8. Agricultural Runoff

River mouth bringing runoff into the ocean, making many layers of colors in concentric rings. Image credit: Cat-Bee/Shutterstock.com
River mouth bringing runoff into the ocean, making many layers of colors in concentric rings. Image credit: Cat-Bee/Shutterstock.com

Industrial agriculture frequently uses chemicals that eventually wash into our rivers and streams. As a result, these harmful substances find their way into the ocean, posing a threat to the surrounding wildlife from the smallest shrimp to the biggest whales. In fact, beached beluga whales who once died due to agricultural runoff had to be treated like toxic waste. Such dangerous chemicals often create “dead zones” in which the oxygen level is so low that all nearby life is forced to migrate or die. Since the 1950s, the existing dead zones have grown four times in size.

7. Oil Spills

Plenty of people are trying to remove the crude oil on oil spill accident by PTT on Ao Prao Beach at Samet island on July 31,2013 in Rayong,Thailand. Image credit: Kajornyot wildlife photography/Shutterstock.com
Plenty of people are trying to remove the crude oil on oil spill accident by PTT on Ao Prao Beach at Samet island on July 31,2013 in Rayong,Thailand. Image credit: Kajornyot wildlife photography/Shutterstock.com

Drilling under the seabed for oil can lead to disastrous consequences. The Deepwater Horizon and Exxon Valdez oil spills are two examples that have caused extreme harm to the surrounding marine wildlife. Contact with the stuff can impair reproductive systems, clog the blowholes of whales and dolphins causing them to suffocate, and permanently destroy the internal organs of mammals who try to lick it off their fur. It can also cause irreparable damage to birds’ feathers. Many marine biologists consider oil spills to be the biggest cause of marine pollution.

6. Plastic Pollution

Humans are huge consumers of single-use, plastic goods, like bottles and bags. Due to our throw-away culture, it is estimated that approximately 8 million tonnes of plastic waste finds its way into our seas and oceans every year, but Greenpeace claims that it could be anywhere up to 12.7 million. If this trend continues, there will be more plastic than fish in our water by 2050. Many sea creatures mistake plastic for food; as a result, it either blocks their airways and suffocates them, or clogs their stomachs so they cannot eat actual food. On average, over one million animals such as fish, turtles, and birds die every year because of plastic pollution.

5. Shipping

Black Smoke from Ship Sailing on the High Sea. Image credit: Mr Nai/Shutterstock.com
Black Smoke from Ship Sailing on the High Sea. Image credit: Mr Nai/Shutterstock.com

Commercial ships are one of the biggest culprits when it comes to pollution. A lot of the garbage accumulated aboard these vessels ends up at the bottom of the ocean. Such waste includes food, packaging, and cleaning materials. In addition to leaking oil and other various chemicals, the two main pollutants found in shipping emissions—Nitrogen oxides and Sulfur oxides—also severely impacts the surrounding marine environment. Lastly, massive ships tend to hit whales and other marine creatures on a regular basis. For example, in Florida alone, over ninety manatees die due to ship collisions every year.

4. Acoustic Pollution

Extreme noise can cause serious harm to marine life. Sources of such noise range from loud engines to drilling rigs, military sonar to entertainment on cruise ships. Sea creatures rely on sound for many things: communication, migration, foraging for food. Excessive noise disrupts these activities. Female whales, for instance, are unable to hear the singing of their male counterparts, frequently missing out on mating opportunities. Other negative impacts of acoustic pollution on marine life include damage to internal organs, forced migration, collisions with passing ships, and overall panic and stress.

3. Overfishing

Blue-fin tuna harvest in Eastern Mediterranean, Turkey. Image credit: Zaferkizilkaya/Shutterstock.com
Blue-fin tuna harvest in Eastern Mediterranean, Turkey. Image credit: Zaferkizilkaya/Shutterstock.com

Overfishing is the act of removing fish from their natural habitats at a rate much faster than they can reproduce, resulting in the global decline of various species. According to the World Wildlife Fund, over thirty percent of the world’s fishing grounds have been depleted. Dragging large nets through open water—or trawling as it is professionally known—is the method of fishing most responsible for this issue. In fact, some species of marine wildlife are being targeted so frequently that they are now endangered, like the Atlantic bluefin tuna. Simply put, the rate that we fish is not sustainable.

2. Commercial Hunting

Shark fins dried under the hot sun at fisherman village in Asia. Image credit: Lano Lan/Shutterstock.com
Shark fins dried under the hot sun at fisherman village in Asia. Image credit: Lano Lan/Shutterstock.com

Many marine creatures are purposely hunted by humans. For example, Japanese fishermen have killed between 200 and 1,200 whales every year since 1987. Sharks in particular have been shrinking rapidly on a global scale because of how mercilessly they are pursued. One reason for this is shark finning. Fishermen catch them only to cut off their fins and throw them half-alive back into the water; these fins are then sold for as much as $500 a pound and used in specialty dishes like soup for the wealthy. Shark finning is responsible for the slaughter of approximately 100 million sharks a year.

1. Tourism

A crowded beach in Phi Phi Island, Thailand. Image credit: Avatar_023/Shutterstock.com
A crowded beach in Phi Phi Island, Thailand. Image credit: Avatar_023/Shutterstock.com

Coastal development for the sake of tourism has caused serious harm to various marine environments over the years, particularly oceans. Natural habitats are destroyed when developers build roads and resorts, forcing the native animals to adapt, relocate, or die. With an abundance of tourists, these beachside hotspots tend to produce more waste as well, which usually finds its way into the water. In addition, sea creatures are frequently killed so souvenir shops can sell novelty gifts like shark teeth, tortoise shell jewelry, and seal fur.

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