threats

The Sounds Of Coral Reefs | Earth Wise

June 23, 2022 By EarthWise Leave a Comment

Coral reefs around the world face multiple threats from climate change, pollution, and other impacts of human activity. Reef conservation and restoration projects must be able to monitor the health of reefs and that is not such a simple matter. Surveying reefs generally is labor-intensive and time consuming. But in a new study, scientists at the University of Exeter in the UK have found a new way to do it.

The fish and other creatures living on coral reefs produce a vast range of sounds. The meaning of these various sounds is for the most part unknown, but reefs nonetheless have distinctive sonic signatures.

The Exeter researchers decided to make use of machine learning technology. They trained a computer algorithm using multiple recordings of both healthy and degraded coral reefs. This essentially taught the computer to learn the difference between them. A computer can pick up patterns that are undetectable to the human year. This application of artificial intelligence can tell us faster and more accurately how a reef is doing.

The computer was then used to analyze a set of new recordings, and successfully identified reef health 92% of the time. The team then was able to use this technique to track the progress of reef restoration efforts.

It is generally much cheaper and easier to deploy an underwater hydrophone on a reef and leave it there instead of having expert divers make repeated visits to a reef to survey its status. Sound recorders and artificial intelligence could be used around the world to monitor the health of coral reefs and determine whether efforts to protect and restore them are working.

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AI learns coral reef “song”

Photo, posted January 11, 2015, courtesy of Falco Ermert via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Manatees And Pollution | Earth Wise

November 11, 2021 By EarthWise Leave a Comment

Manatees are large, gentle, and curious marine mammals measuring up to 13 feet long and weighing up to 3,300 lbs. There are three living species of manatees: The Amazonian Manatee, the West African Manatee, and the West Indian Manatee, which is commonly found in Florida and the Gulf Coast. Manatees inhabit the shallow, marshy coastal areas and rivers of the Caribbean Sea, the Gulf of Mexico, the Atlantic coast, the Amazon basin, and West Africa.

The West Indian Manatee, which includes the Florida Manatee, is protected under the Endangered Species Act. Today, the range-wide population is estimated to be at least 13,000 manatees, with more than 6,500 in the southeastern United States and Puerto Rico.

In Florida, an uptick in nutrient loading from nonpoint sources is triggering algal blooms in Indian River Lagoon and neighboring areas. These algal blooms have decimated seagrass, manatees’ primary food source.

As a result , manatees have starved to death by the hundreds along Florida’s east coast. The state has recorded 974 manatee deaths in 2021, shattering previous annual all-time highs with still approximately two months to go. Manatees, which need to eat between 100-200 pounds of seagrass daily, are now eating the seagrass roots, which permanently kills the aquatic plants.

Efforts are being made to replant seagrass and to restore clam and oyster beds so that the mollusks can help clean the water. But manatees face a myriad of additional threats, including collisions with boats and ships, temperature changes, disease, and crocodile predation.

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Florida lawmakers hear Fish & Wildlife agency response to manatee death ‘catastrophe’

West Indian manatee

Preliminary 2021 Manatee Mortality Table by County

Photo, posted May 7, 2010, courtesy of Jim Reid/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Assisting Evolution | Earth Wise

March 11, 2021 By EarthWise Leave a Comment

As plants and animals around the world grapple with climate change, invasive species, disease, and other threats, conservationists grapple with the issue of what it means to protect what is natural and how far to go to prevent extinctions.

Australia is where many of these issues have risen to the forefront. Imported mammals – particularly cats and foxes – have decimated many of Australia’s indigenous marsupials. Much of the focus for decades has been on killing off the invaders and cordoning off protected animals. In recent years, however, there have been efforts to expose prey animals to limited numbers of predators to develop prey populations that are better equipped to survive among predators. Getting rid of all the predators is not realistic. Saving species may require helping them to adapt.

On the Great Barrier Reef, where half its coral populations have perished because of rising water temperatures, scientists are breeding corals that are more heat tolerant. They are even considering the use of gene editing technology to “assist evolution” in developing corals that can survive in a changing world.

At SUNY College of Environmental Science and Forestry in Syracuse, New York, researchers have produced a genetically modified American chestnut tree that is resistant to chestnut blight, the fungal pathogen that killed off nearly every chestnut tree in North America in the early 20^th century.

The idea of conservation is to protect what is natural in our world. However, at a time when there are unprecedented threats to so many species, the distinction between what is natural and what is artificial may no longer provide a sound guide to what should be done to protect life on earth.

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Assisting Evolution: How Far Should We Go to Help Species Adapt?

Photo, posted November, 2000, courtesy of Bernard Dupont via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Decline In Wildlife | Earth Wise

October 14, 2020 By EarthWise Leave a Comment

According to a new report released by the World Wildlife Fund, global populations of mammals, birds, amphibians, reptiles, and fish have declined by 68% in less than half a century.

The report presents a comprehensive overview of the state of the natural world based on the tracking of almost 21,000 populations of more than 4,000 vertebrate species between 1970 and 2016.

The report shows that the main cause of the dramatic decline in species populations on land is habitat loss and degradation, which includes deforestation driven by food production. Additional factors include land-use change and the use and trade of wildlife.

Wildlife populations found in freshwater habitats have suffered a decline of 84%, which is the steepest decline in any biome.

Insect populations have declined rapidly in many places, but most of the information about insects comes from a small number of countries in the northern hemisphere. There is very little information from large parts of the world, such as Africa, South America, and Asia, where land-use change and agricultural expansion are happening fast. What happens to insects matters a lot to humanity. Insects play central roles in the world’s ecosystems as waste processors, pollinators, predators, and prey.

The report is clear evidence of the damage human activity is doing to the natural world. Threats to the integrity of ecosystems endanger humans and all of nature. This is especially apparent in the midst of a global pandemic. It is now more important than ever to take coordinated global action to halt and reverse the loss of biodiversity and wildlife populations across the globe.

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Living Planet Report reveals 68% decline in global wildlife populations since 1970

Photo, posted May 7, 2020, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Native Bees In A Honeybee World | Earth Wise

September 21, 2020 By EarthWise Leave a Comment

There is a great deal of attention on the plight of bees and other pollinators. Much of that focuses on the problems plaguing the large, domesticated honeybee colonies that are trucked from region to region to pollinate everything from almonds to fruit trees. Managed bee colonies have recently been losing more than 40% of their population over the course of a year. But overall, honeybees are still relatively safe. They are a globally distributed, domesticated species and are not remotely threatened with extinction.

But another group of bees – native bees – faces a different range of threats, most linked to habitat loss. Worldwide, roughly 20,000 native bee species have evolved over millions of years to thrive in countless habitats, where they have specialized in pollinating specific flowers and plants – in some cases just a single plant.

Scientists have estimated that, globally, 1 in 6 bee species is regionally extinct. In the United States there are about 4,000 native bee species, most of which are solitary bees that nest in the ground or cavities, with many that require just one or a few plant species for sustenance. At least 23 percent of U.S. native bees have declined, with bees in areas with heavy commodity-crop production particularly hard hit due to habitat loss and pesticide use. Other threats to native bees include climate-driven sea-level rise and increased temperatures, loss of host plants, and competition and disease from non-native honeybees. 50% of Midwestern native bee species disappeared from their historic ranges in the last 100 years. Four of our bumblebee species declined 96% in the last 20 years, and three species are believed to already be extinct.

Native bees are in big trouble.

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Backyard Battle: Helping Native Bees Thrive in a Honeybee World

Photo, posted December 2, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tough Times For Fireflies | Earth Wise

March 11, 2020 By EarthWise Leave a Comment

Fireflies or lightning bugs are soft-bellied beetles known widely for their use of bioluminescence – the biochemical emission of light – to communicate and to attract mates. There are more than 2,000 species of these beetles globally. They can be found in temperate and tropical climates, like marshes or wet, wooded areas, all throughout the world.

But if you are seeing fewer fireflies each summer, you’re not alone. Like many insects, firefly populations are under duress from threats like pesticides, pollution, and habitat loss. But fireflies are also facing another threat unique to luminous bugs: light pollution. Light pollution is making it harder for fireflies to reproduce because the artificial light is outshining their mating signals.

Male fireflies light up to signal availability and female fireflies respond with patterned flashes to indicate they’re interested. But artificial bright light from things like billboards, streetlights, buildings, and homes, is interfering with the fireflies reproduction communications.

The study, by researchers at Tufts University and the IUCN, warned that these threats facing fireflies could lead them globally to extinction.

The researchers also point to habitat loss as another major threat to fireflies. Firefly populations are especially vulnerable because they need special conditions to complete their life cycle. Mangrove forests and marshes around the world are being removed in favor of cash crops like palm oil.

Insects like fireflies are crucial components of many ecosystems where they perform important functions, like aerating soil, pollinating plants, and controlling pests. Firefly larvae feed on snails, slugs and mites, and many fireflies are effective pollinators.

We can’t afford for fireflies to go dark.

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A Global Perspective on Firefly Extinction Threats

Fireflies Have a Mating Problem: The Lights Are Always On

Photo, posted June 5, 2010, courtesy of Matt MacGillivray via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Banning The Shark Fin Trade

July 4, 2019 By EarthWise Leave a Comment

Shark fins are considered a delicacy in many parts of the world, especially in China. Shark fin soup, for example, is often served at engagement parties and weddings. But the use of shark fins has come under increasing scrutiny in recent years, especially since an estimated one-third of fins are harvested from species deemed at risk.

Many of the fins used in shark fin soup come from a practice known as “finning,” which is an inhumane and wasteful practice where the fins are hacked from live sharks and then the sharks are thrown back into the water and left to die. According to U.N. estimates, 73 million sharks are killed every year for their fins.

The possession, sale, and distribution of shark fins is banned in 12 U.S. states, as well as in all European Union member states.

In 1994, Canada banned the practice of finning in its own waters, but allowed the import of fins to continue. Canada has been one of the largest markets for shark fins outside Asia, importing nearly 300,000 pounds of shark fins last year. But in late June, Canada passed a bill that bans both the import and export of shark fins harvested by shark finning. They are the first G7 and the first G20 country to do so.

But shark fins taken from sharks sustainably harvested for their meat will continue to be allowed in Canada. While demand for shark fins is decreasing globally, demand for shark meat is rising.

Since sharks still face a myriad of environmental pressures, including illegal fishing and high bycatch rates, there are concerns that this Canadian ban oversimplifies the threats facing global shark populations.

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