marine species

Sharks On The Decline | Earth Wise

September 4, 2020 By EarthWise Leave a Comment

During the past 70 years, global shark populations have been on the decline. Many species have become threatened or endangered. Conservation efforts have been underway in many places, but shark populations continue to be at risk because of over-fishing and habitat loss.

A comprehensive study by marine biologists at Texas A&M University deployed more than 15,000 baited remote underwater video stations on 371 coral reefs in 58 countries. The study included 59 different shark species in the Atlantic, Pacific and Indian Oceans. The researchers were surprised to find that no sharks at all were detected in almost 20% of the locations surveyed and were almost completely absent from coral reefs in several nations.

Scientists believe that demand for shark products, such as fins and meat, and bycatch (that is, sharks captured in nets by fisherman trapping other kinds of fish) are strong contributors to the widespread declines in shark numbers around the world.

The study shows that if corrective steps are not taken in regions where marine management is still ineffective, continued depletion of shark populations is highly likely.

Sharks have important roles in marine ecosystems. When their habitats deteriorate and their populations decrease, ecosystem stability and health is degraded because sharks help regulate prey populations.

Some countries, notably the Bahamas, are combating the problem by providing sanctuaries for sharks where fishing and harvesting is prohibited. Such places support some of the healthiest shark populations in the world. However, the decline of coral reefs is just another challenge facing shark populations around the world.

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Study Shows Alarming Decline In Shark Numbers Around The World

Photo, posted January 9, 2017, courtesy of Kris-Mikael Krister via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recovering Marine Life By 2050 | Earth Wise

May 27, 2020 By EarthWise Leave a Comment

Marine life has faced challenges for a long time. There have been centuries of overfishing in many places and pollution of various types has been especially harmful in recent decades. But despite all of this, a new scientific review published in the journal Nature contends that marine life in the world’s oceans could be fully restored in as little as 30 years provided that aggressive conservation policies are adopted.

The research spotlights the strong resiliency of ocean animals and cites the successful recovery of a number of marine species, including humpback whales.

The study indicates that nations around the world must agree to designate 20 to 30 percent of the oceans as marine protected areas, institute sustainable fishing guidelines, and regulate pollution. These measures would not come cheaply. The estimated cost would be around $20 billion a year.

However, the report also estimates that the economic return on this investment would be tenfold and would create millions of new jobs. Rebuilding fish stocks and maintaining sustainable fishing policies could increase global profits of the seafood industry by over $50 billion a year. Conserving coastal wetlands could save the insurance industry more than $50 billion a year as well by reducing storm damage.

A major sticking point, however, is climate change. Climate change is increasing ocean temperatures and driving acidification. Unless these changes are brought under control, the restoration of marine life is not going to be successful. We have reached the point where it is within our power to choose between a future with a resilient and vibrant ocean or an irreversibly disrupted ocean. Whether we embrace that challenge remains to be seen.

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Marine Life Could Recover By 2050 With the Right Policies, Study Finds

Photo, posted April 20, 2012, courtesy of Matthias Hiltner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Balloons And Seabirds

March 19, 2019 By EarthWise Leave a Comment

It’s no secret that there is a ton of plastic in the ocean – millions of tons, in fact. Scientists estimate that there is more 165 million tons of plastics swirling about in our oceans today, with an additional 8.8 million tons flowing in every year. As the oceans swell with plastic debris, many marine species wind up ingesting the stuff – often with dire consequences.

All this plastic trash winds up affecting more than just aquatic species, too. According to researchers from the University of Tasmania, a seabird that ingested a single piece of plastic has a 20% chance of mortality. This statistic jumps to 50% if the seabird consumes nine pieces of plastic.

The study, which was recently published in the journal Scientific Reports, also found that while hard plastics account for the majority of plastic debris ingested, it’s far less likely to prove fatal than soft plastics, such as balloons.

In fact, the researchers found that balloons or balloon fragments were the number one marine debris risk of mortality for seabirds, killing almost one in five of the seabirds that ingested them.

The leading cause of death among the seabirds studied was blockage of the gastrointestinal tract. While soft plastics only accounted for 5% of the ingested plastics, they were responsible for more than 40% of seabird mortality. But the researchers make clear that hard plastics were still responsible for more than half of the study’s seabird deaths.

If we want to reduce the number of marine species dying from plastic ingestion, we need to reduce the volume of plastic going into the ocean and do what we can to remove what’s already there.

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Balloons the number 1 marine debris risk of mortality for seabirds

Photo, posted July 24, 2014, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saildrones For Science

July 11, 2018 By EarthWise Leave a Comment

Nine years ago, engineer Richard Jenkins broke the world land speed record for a wind-powered vehicle with a sailboat on wheels driving across a dry lakebed at 126 miles per hour. After years of engineering development, his technology has now taken on the form of a saildrone that can autonomously sail the sea gathering ecologic, oceanic and atmospheric data.

Tsunami And Invasive Species

November 13, 2017 By EarthWise Leave a Comment

According to a new study published in the journal Science, scientists have discovered that hundreds of Japanese marine species have been swept across the Pacific Ocean to the United States following the deadly Tsunami in 2011.

Why Do Animals Eat Ocean Plastic?

November 21, 2016 By WAMC WEB

It’s no secret that there is a lot of plastic debris in our oceans. In fact, scientists estimate that there is more than 165 million tons of plastic trash swirling about in our oceans today, with an additional 8.8 million tons flowing in every year. And as the oceans swell with plastic litter, hundreds of marine species are ingesting the stuff – often with dire consequences.