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Plastic Eating Fungus | Earth Wise

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More than five billion tons of plastic have accumulated on land and sea including the most remote regions of the planet as well as in the bodies of animals and humans.  There is a compelling need to recycle as much plastic as possible but doing so is a major challenge. Plastic comes in many varieties and breaking it down for reuse requires different methods for each.

Polypropylene is one of the biggest challenges for recycling.  It is a very common plastic used for all sorts of products including food containers, coat hangers, plastic wrap, toys, and much more. It accounts for roughly 28% of the world’s plastic waste, but only 1% of it is recycled.

Polypropylene is seldom recycled because it generally has a short life as a packaging material, and it often becomes contaminated by other materials and plastics.  Thus, it generally ends up in landfills.

Researchers at the University of Sydney in Australia have discovered that two common strains of fungi were able to successfully biodegrade polypropylene.  The fungi species – with unavoidable Latin names of Aspergillus terreus and Engyodontium album – are typically found in soil and plants.

The researchers found that the fungi were able to break down polypropylene after it had been pre-treated with either UV light or heat, by 21% over 30 days, and by 25-27% over 90 days.  This seems rather slow but compared with the nearly endless life of polypropylene in landfills, it is a major improvement.

The hope is that methods like this could ultimately reduce the amount of plastic polluting the environment by encouraging plastic to biodegrade naturally under the appropriate conditions.

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Fungi makes meal of hard to recycle plastic

Photo, posted March 5, 2010, courtesy of Kevin Krejci via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Life In The Garbage Patch | Earth Wise

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A team of scientists has found thriving communities of coastal creatures living thousands of miles from their original homes and now ensconced on plastic debris in the Great Pacific Garbage Patch. 

A new study published in the journal Nature Ecology & Evolution reports that dozens of species of coastal invertebrate organisms – including tiny crabs and anemones – have been able to survive and reproduce on plastic garbage that has been floating in the ocean for years.

The Great Pacific Garbage Patch is an area in the ocean between California and Hawaii, larger than Texas, where plastic debris has been collected by the North Pacific Subtropical Gyre, one of five huge, spinning circular currents in the world’s oceans.  The patch is estimated to contain about 1.8 trillion pieces of plastic weighing an estimated 90,000 tons.  The Ocean Cleanup Initiative is dedicated to removing this immense accumulation of plastic, but it is an immense job.

Researchers discovered this new ecosystem after analyzing plastic samples collected by The Ocean Cleanup organization during its expeditions in the Pacific.  They were surprised to find 37 different invertebrate species that normally live in coastal water and only a dozen species that live in open waters.  These species have made their way from North America and have thrived.  So, the garbage patch has created a novel community that didn’t previously exist.

Debris from the Great Pacific Garbage patch constitutes the majority of debris arriving on Hawaiian beaches and reefs.  Hawaii’s fragile marine ecosystems have long been protected from invasive species because of the very long distances from North America or Asia.  With the coastal species now inhabiting the garbage patch, there is increased danger of colonization by them in Hawaii’s ecosystems.

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Coastal species persist on high seas on floating plastic debris

Photo, posted September 30, 2020, courtesy of Kees Torn via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Salt Marshes And Climate Change | Earth Wise

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Salt marshes are coastal wetlands that are flooded and drained by salt water brought in and out by the tides. These low-lying wetlands are also sometimes called tidal marshes because they occur in the zone between low and high tides. These wetlands are some of the most biologically productive ecosystems on Earth.

Cape Cod’s beautiful salt marshes are as important as they are iconic.  They act as carbon sinks, protect coastal development from storm surge, play an outsized role in nitrogen cycling, and provide critical habitats for many fish, shellfish, and coastal birds.

According to scientists from the Marine Biological Laboratory in Woods Hole, Massachusetts, more than 90% of salt marshes around the world are likely to be underwater by the end of the century. 

Since 1971, scientists from the Marine Biological Laboratory have mapped vegetative cover in Great Sippewissett Marsh in Falmouth, Massachusetts, to examine whether increased nitrogen in the environment would impact species of marsh grass.  Because of the length of the study, the researchers were also able to investigate the impacts of climate change on the ecosystem, especially those driven by accelerating sea level rise. 

The research team found that increased nitrogen favored higher levels of vegetation and accretion of the marsh surface.  However, the researchers found that salt marshes will not be able to outpace the submergence from global sea level rise – no matter how much nitrogen is applied.

Sea level rise is the biggest threat to salt marshes around the world.  Mitigating some of these projected losses is critical in order for salt marshes to continue to provide their important ecosystem services for people and the planet.  

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Most of the World’s Salt Marshes Could Succumb to Sea Level Rise by Turn of Century

Photo, posted September 27, 2011, courtesy of Chris M Morris via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Counting Trees | Earth Wise

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Scientists estimate that there are about 3 trillion trees on the earth.  A huge number but probably half as many as there were before people entered the picture.  And we’re losing about 10 billion trees a year to toilet paper, timber, farmland expansion, and other human activity.  Trees play a crucial role in taking carbon dioxide out of the atmosphere and storing it away.  For this reason, trees have become an integral part of the effort to mitigate climate change.

There are major initiatives underway around the world to plant more trees.  Part of this is driven by the increasing use of carbon credits by companies trying to offset their carbon emissions.   These credits are earned by either planting new trees or paying farmers or other landowners not to cut down existing trees.  But how many trees are actually planted and how many survive over time?

Whether these efforts are really resulting in more trees and more carbon storage is not easy to determine.  Current international inventories of global tree-sequestered carbon are subject to great uncertainty.

Researchers from the University of Copenhagen and NASA have developed a method for mapping large numbers of trees and determining their carbon content.  Using artificial intelligence techniques to analyze ultra-high-resolution satellite images, they can count trees, determine their individual species, and measure their carbon content.

A study of images from Africa’s Sahel region found that it is home to nearly 10 billion trees that are currently storing 840 million tons of carbon.

Now that the groundwork for this new methodology is complete, it is ready to be deployed by public agencies, NGOs, and other interested in monitoring the numbers of trees and their carbon content.

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The counting of nine billion trees could help manage climate credits and nature restoration

Photo, posted October 27, 2018, courtesy of Ian Dick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Spiders And Pest Control | Earth Wise

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Climate change facilitates the spread of invasive pest species by expanding their habitable environment ranges.  In conventional agriculture, farmers depend on chemical pesticides to control agricultural pests.  But 99% of all synthetic chemicals, including pesticides, are made from fossil fuels, and turning petrochemicals into pesticides requires massive amounts of energy.  These chemical pesticides also pollute the air and water, and destroy biodiversity by killing many non-target species as well.  

According to new research led by scientists from the University of Portsmouth in the U.K., groups of spiders could be used as an environmentally-friendly way to protect crops against agricultural pests.  The study, which was recently published in the journal Insects, suggests that web-building groups of spiders can be used to control populations of the tomato leafminer moth, a devastating pest of commercially important crops like tomatoes and potatoes.

The research team explored the use of tropical tent spiders for this pest control.  They are found in colonies around the world, and their range overlaps with regions of moth infestations, including Mediterranean Europe, Africa, Asia, and the Middle East.

In lab settings, different types of prey were introduced to colonies of spiders of varying body sizes.  The research team found that the larger spiders built larger webs and caught more prey, including tomato leafminer moths and fruit flies.   

Tropical tent spiders could be an effective and climate-friendly way to control flying insect pests.  However, more research is needed to ensure that these spiders don’t negatively impact crop pollination by also catching pollinators.

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Using spiders as environmentally-friendly pest control

Photo, posted June 10, 2018, courtesy of Lies Van Rompaey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How To Meet Protected Land Targets | Earth Wise

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More than half of the world’s countries have set a target of setting aside 30% of land and sea areas across the globe for conservation by 2030, in order to preserve and protect nature and essential services to people.  This pledge creates some difficult questions to answer.

What sorts of land should be protected and where should it be located?  What effects of these new land protections will there be on carbon emissions and the climate and on land usage for food production and energy generation?  Policymakers have to grapple with such questions in order to move forward on these ambitious biodiversity protection goals.

A recent study by the Lawrence Berkeley National Laboratory attempts to answer many of these questions.  The study found that meeting the 30% goal could lead to substantial regional shifts in land use and, in some cases, still fail to protect some of the most important biodiversity hotspots.

Protecting land entails tradeoffs with other land uses and can have negative impacts on the agricultural sector as well as land use for bioenergy crops and forest land use for timber.

In particular, the study found that the amount of land used for crops for conversion into biofuels could be significantly impacted by doubling current protected areas while still preserving the amount of land used for food crops.  This is particularly true for land in Russia and Canada.

The study also found that while it may be possible to meet the 30% target by only protecting agriculturally unsuitable land, it may not end up protecting many of the world’s 36 identified biodiversity hotspots.  The uneven distribution of species has a significant bearing on how to manage the conservation of biodiversity.

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Doubling Protected Lands for Biodiversity Could Require Tradeoffs With Other Land Uses, Study Finds

Photo, posted September 19, 2020, courtesy of John Brighenti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Protected Areas Are Not Protecting Insects | Earth Wise

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Insects can be found in every environment on Earth and play crucial roles in the planet’s ecosystems.  In fact, Biologist E. O. Wilson once said that “if all mankind were to disappear, the world would regenerate back to the rich state of equilibrium that existed ten thousand years ago.  If insects were to vanish, the environment would collapse into chaos.”

While his statement may sound extreme, it’s really not an exaggeration.  Insects are critical to most ecosystems.  They pollinate more than 80% of plants – both those we eat and those that provide food and habitat for other species.  Insects are also a food source themselves, eaten by other insects, birds, fish, and mammals. Without insects, we wouldn’t have the rich biodiversity that supports life on earth today. 

But insect populations are collapsing around the globe, and they continue to be overlooked by conservation efforts.  Protected areas, like national parks, refuges, and sanctuaries, can safeguard threatened species, but only if those threatened species actually live within the protected areas. 

According to a new study recently published in the journal One Earth, 76% of insect species are not adequately covered by protected areas, including several critically endangered insects such as the dinosaur ant, crimson Hawaiian damselfly, and harnessed tiger moth. Alarmingly, the populations of 1,876 species do not overlap with protected areas at all.

Insects have been historically overlooked by conservation programs and need to be included in future conservation assessments. 

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Protected areas fail to safeguard more than 75% of global insect species

Photo, posted August 21, 2014, courtesy of Andy Reago & Chrissy McClarren via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Insects On The Menu | Earth Wise

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According to the World Food Programme, a record 349 million people across 79 countries are facing acute food insecurity.  This constitutes a staggering rise of 200 million people compared to pre-pandemic levels.  Nearly one million people globally are fighting to survive in famine-like conditions, which is ten times more people than just five years ago.  

As a result, many experts contend that alternative or so-called novel food sources – such as lab-grown meats, seaweed aquaculture, and insects – will be necessary to help fight global hunger and global food insecurity. 

Insects already form a significant part of diets in many cultures around the world.  Insects are great sources of nutrients, including protein, vitamins, and minerals.  But insects have yet to be embraced in any substantial way in western cultures… but that may be changing. 

In fact, the European Union has now certified four types of bugs as food fit for human consumption.  The larvae of lesser mealworms and house crickets recently became the third and fourth insects approved for sale as food in the EU, joining yellow mealworms and grasshoppers. Eight more applications are awaiting approval.

Insects are already a delicacy in many high-end restaurants around the world, and a normal and healthy part of diets in countries like Mexico and Thailand.  Embracing insects as a food of the future will not only help in the fight against global hunger, but will also help to reduce greenhouse gas emissions and to slow species extinction. 

In Western food markets, the so-called “yuck factor” remains the biggest hurdle to cross.  But as the world population grows, the need for sustainable solutions in the food industry grows with it. 

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Insects on the menu as EU approves two for human consumption

World Hunger Surged in 2020, U.N. Says

A global food crisis

Photo, posted April, 2014, courtesy of Shankar S. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How To Save Big Cats | Earth Wise

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Big cats are among the most widely recognized and admired animals in the world. But these charismatic predators face many and varied threats, including the loss of habitat and prey, conflicts with humans, poaching, and the illegal wildlife trade.

Researchers from the University of Reading in the U.K. have studied the fortunes of 50 species of large carnivores worldwide over the past 50 years.  They found that social and economic factors, such as quality of life, were more closely associated with declines of large carnivore species than purely environmental factors, like habitat loss.   

The study, which was recently published in the journal Nature Communications, suggests that the best way to save large carnivores, including lynx, bears, and lions, is to encourage a sustainable model of social and economic development instead of focusing exclusively on issues like climate change.  

While rapid economic development pushes species to the brink of extinction, it’s also delivered enormous improvements in the quality of human life. But the analysis suggests that once people achieve a high quality of life and economic development slows, a turning point is reached and persecuted species have a chance to recover.

According to the research team, the recovery is a result of both improved habitat protections in advanced economies and a more harmonious relationship between people and predators.  What would have once been considered a dangerous pest is now recognized as being an important part of both the ecosystem and culture.  

In Western Europe, slower economic development and an improved quality of life have allowed populations of grey wolves to increase 1,800% since the 1960s.

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Economics trump environment to save big cats, say ecologists

Photo, posted February 8, 2015, courtesy of Mathias Appel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking Global Forest Changes | Earth Wise

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India is one of the most biodiverse countries in the world.  An estimated 47,000 plant species and 89,000 animal species can be found in India, with more than 10% of each thought to be on the list of threatened species.

India is also one of the 10 most forest-rich countries in the world.  Trees cover approximately 25% of the nation.  But this is still a significant decline from years past.  In fact, between the 1890s and 1990s, a combination of rapid development and resource overexploitation caused India to lose nearly 80% of its native forest area.  Today, as India’s forests continue to disappear, researchers are trying to help preserve what forest remains. 

Using satellite-monitoring data, researchers from The Ohio State University have developed a deep learning algorithm that could provide real-time land use and land cover maps for parts of India. 

The land use monitoring system was trained using satellite data from Norway’s International Climate and Forests Initiative.  By combining this data with a global land cover map produced by Tsinghua University in China, the researcher team’s deep learning model was able to acquire a more detailed type of base map of the area.  Using their model, the researchers were able to process 10 monthly maps.  Their research was recently  presented at the annual meeting of the American Geophysical Union.   

Using these maps, the researchers were able to detect seasonal shifts across india.  These include changes to barren land, how crop land was affected by monsoons, and the distribution of forests in mountainous regions. 

Understanding the impact of these seasonal changes will help scientists better predict the effects of climate change on forests.

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Using deep learning to monitor India’s disappearing forest cover

Photo, posted January 20, 2013, courtesy of Frontier Official via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An Agreement To Protect Biodiversity | Earth Wise

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The UN Biodiversity Conference in Montreal in December concluded with a historic deal aimed at stemming the rising tide of extinctions.  Nearly 200 countries signed on to the agreement to protect 30% of the Earth’s land and sea by the end of this decade.

Part of the agreement also pledges that countries will reduce fertilizer runoff from farms by 50%, reduce the use of harmful pesticides by 50%, and stem the flow of invasive species. 

Of course, all of these promises are only words unless they are backed up by actions and actions cost money.  The agreement promises to direct $200 billion a year towards biodiversity by the end of this decade.  Wealthy countries were urged to provide $100 billion a year to fund the actions of poorer countries, but they resisted the pressure.  Eventually, they did agree to send $30 billion a year to developing countries by 2030.

It is a significant step forward to establish clear targets for stopping biodiversity loss.  However, the ultimate success of the pact will depend on the willingness of countries to cooperate and compromise.

According to UN estimates, about a million species across the globe face extinction as a result of rising temperatures, air and water pollution, invasive species, and habitat loss due to development.   At present, only 16% of land and 8% of the oceans are within protected areas. 

The UN Environment Program stated that “for far too long humanity has paved over, fragmented, over-extracted, and destroyed the natural world on which we all depend.  Now is our chance to shore up and strengthen the web of life, so it can carry the full weight of generations to come.”

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In Historic Deal, Countries Agree to Protect 30 Percent of Earth to Halt Biodiversity Loss

Photo, posted August 13, 2015, courtesy of Andrew H via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Assessing The Planet’s Most Unique Birds | Earth Wise

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Birds come in a huge variety of shapes, sizes and plumages.  The physical attributes of birds are adaptations that have taken countless millennia to develop, and physical attributes are closely related to the roles birds play in their environment.   

According to a new study led by researchers from the University College London in the U.K., bird species with extreme or uncommon combinations of traits have the highest risk of extinction.  Losing these bird species and the unique roles they play in the environment, including seed dispersal, pollination and predation, could have severe consequences on the health of ecosystems.

In the study, which was recently published in the British Ecological Society journal Functional Ecology, the researchers analyzed the extinction risk and physical attributes of 99% of all living bird species.  The research team used a dataset of measurements collected from living birds and museum specimens.  The measurements included things like beak size and shape, and the length of wings, tails and legs.  The researchers combined this data with extinction risk, and then ran simulations to see what would happen if the most threatened birds were to go extinct.

Some of the bird species that are both most unique and most threatened include the Christmas Frigatebird and the Bristle-thighed Curlew.  Kiwis were excluded from the study because the researchers viewed them as extreme morphological outliers.

While most unique birds were also classified as threatened on the Red List, the research was unable to show what links uniqueness in birds to extinction risk

The research team warns that if more isn’t done to protect these threatened species and avoid extinctions, the functioning of ecosystems will be dramatically disrupted.

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Planet’s most unique birds at higher risk of extinction

Photo, posted June 25, 2012, courtesy of Kristine Sowl / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Sumatran Rhino | Earth Wise

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The Sumatran rhinoceros is the smallest and most ancient rhino species and is the only surviving species with hair.  It is critically endangered.  Because of poaching and habitat destruction, there are fewer than 50 of them left in the wild and those are scattered in the rainforests of Sumatra and the Indonesian part of Borneo.  Mating encounters between surviving males and females are increasingly rare.

The last male Sumatran rhino in Malaysia died in 2019 but cell samples from that individual are the basis of an ambitious effort in bioengineering.

Researchers from the Max Delbruck Center in Germany are taking skin cells from the deceased rhino and turning them into stem cells.  The hope is to use these stem cells to derive egg and sperm cells to be the basis of assisted reproduction.  Fertilization would take place in a petri dish.  The resultant embryos would then be carried to term by surrogate rhino mothers.

The researchers have reported success generating induced pluripotent stem cells or IPS cells from the rhino skin samples.  IPS cells are able to divide indefinitely and can transform into any cell type in the body.

The next step is to try to cultivate primordial germ cells – the precursors of eggs and sperm.

This work is going on because it is increasingly difficult to preserve the Sumatran rhino population by gathering together remaining individuals in wildlife Reserves.  Females that have not been pregnant for a long time often become infertile because of cyst growth on their reproductive organs, and some are just too old to bear young.

It may take extraordinary efforts like these to save these animals from extinction.

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A second chance for the Sumatran rhino

Photo, posted April 30, 2008, courtesy of Willem V. Strien via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moving Endangered Species | Earth Wise

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People have intentionally or accidentally introduced numerous invasive species to habitats around the world.  At the same time, the planet’s wildlife is in a steep decline.  A recent study estimated that the populations of over 5,000 vertebrate species have declined by an average of nearly 70% since 1970.  A United Nations report warns that human activity has threatened as many as a million species with extinction.

With all of this as a background, there is climate change that is altering the habitats of the world’s species – warming lakes and oceans, turning forests into grasslands, tundra into woodland, and melting glaciers.  In response to these changes, living things are rearranging themselves, migrating to more hospitable locations.  But many species are just not capable of finding more suitable habitats on their own.

Conservationists are now increasingly considering the use of assisted migration. In some cases, when a species’ critical habitat has been irreversibly altered or destroyed, agencies are establishing experimental populations outside of the species’ historical range.  Such actions are often deemed extreme but may be increasingly necessary.

However, clear-cut cases are relatively rare.  More likely, it is a more difficult judgement call as to whether assisted migration is a good idea or is possibly a threat to the ecosystem of the species’ new location.  The relative dearth of assisted migration experiments is less likely a result of legal barriers than it is a lack of scientific and societal consensus on the practice. Scientists are now trying to develop risk-analysis frameworks that various agencies can use in considering potential assisted migration experiments. 

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Last Resort: Moving Endangered Species in Order to Save Them

Photo, posted March 18, 2010, courtesy of Jean via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The State Of The Birds | Earth Wise

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The U.S. Committee of the North American Bird Conservation Initiative has published the State of the Birds 2022, an assessment of bird populations in North America. The news is not good.  The report identifies 70 Tipping Point species, which are those that have lost half or more of their breeding population since 1970 and are on track to lose another half or more in the next 50 years. According to research published in Science in 2019, the United States and Canada have lost 3 billion breeding birds since 1970, which is about a quarter of the total population.

More than half of the bird species in the United States are in decline. According to the Conservation Initiative, the tipping point species in particular require proactive conservation protections to avoid becoming endangered.  Species that inhabit grasslands are declining more rapidly, while waterfowl like ducks and geese are actually increasing.  That increase is most likely a result of the investments in conservation funded by the hunting industry.

Those waterfowl gains demonstrate that when there are concerted efforts to protect and promote bird populations, positve changes can happen.  Some say that protecting birds is not a high priority given all the other crises in the world, but what is good for birds is also good for people.  For example, planting trees and other vegetation to enhance bird habitat also helps to sequester carbon, protect coastlines from storm surges, increase groundwater recharge, and reduce urban heating effects.

The loss of 3 billion birds is a major biodiversity crisis and requires action.  Bird conservation benefits wildlife, people, entire ecosystems, and our planet.

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What’s Good for Birds Is Good for People and the Planet. But More Than Half of Bird Species in the U.S. Are in Decline

Photo, posted November 4, 2020, courtesy of Tom Koerner/U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Living Planet Index | Earth Wise

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The World Wildlife Fund and the Zoological Society of London recently published the latest Living Planet Index, which is designed to measure how animal populations are changing through time.  The purpose is to provide an assessment of the health of ecosystems and the state of biodiversity.

The LPI only looks at the population of vertebrates:  birds, mammals, reptiles, amphibians, and fish.  The latest survey looked at how populations have changed between 1970 and 2018.  The results are that populations of these animal groups have declined by an average of 69% over that 48-year period.

This result highlights a very real and very severe crisis of biodiversity loss.  However, it does not mean that there are 2/3 fewer animals today than 48 years ago.  The way the index is calculated is to look at the changes in individual populations of over 5,000 different species.  Then these individual relative declines are averaged to get the result.  

There are shortcomings in the LPI.  For example, individual species that have seen massive population declines will bring the average down.  But even removing the outliers both of a negative and a positive impact does not dramatically change the result.

There is no perfect indicator for biodiversity and ecosystem health.  The Living Planet Index is nonetheless a useful metric and indicates that many species around the world are in decline.  Policymakers and environmental advocates need to make decisions about conservation and protection measures and this index is one tool they can use.

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There’s a frightening new report about wildlife declines. But many are getting the story wrong.

Photo, posted October 12, 2019, courtesy of Visit Rwanda via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Snail Darter Is Safe | Earth Wise

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The snail darter is a three-inch-long snail-eating fish that was once only found in the Little Tennessee River.  When that river was going to be dammed by the Tellico Dam under construction in the 1970s, the snail darter was listed on the endangered species list and the little fish subsequently became the subject of a legal battle that made it all the way up to the U.S. Supreme Court.   With the dam project 95% complete in 1978, the Supreme Court blocked further construction, citing the Endangered Species Act.  A year later, Congress exempted the project from the requirements of the Act, thereby clearing the way for the completion of the dam.

In order to save the snail darter, biologists transplanted the fish into several other nearby rivers and waterways.  In addition, the Tennessee Valley Authority modified the operation of the Tellico Dam to release more oxygen-rich water downstream.  Beyond those measures, the river cleanup under the Clean Water Act further aided the fish’s recovery.

In 1984, the snail darter was removed from the endangered species list and was listed as threatened or vulnerable.  Recently, the U.S. Department of the Interior officially removed the snail darter from the federal list of threatened and endangered wildlife. 

The snail darter is the fifth fish species to be delisted because its population has recovered.  It is the first in the eastern United States.  With better management of water releases at dams, many other imperiled aquatic species could be recovered.

Overall, more than 50 plants and animals have recovered under federal protection, including American alligators, humpback whales, peregrine falcons, and bald eagles.

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Once at Center of Controversial Case, the Snail Darter Fish Is No Longer Threatened

Photo, posted July 22, 2015, courtesy of The U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Planting Millions Of Trees Isn’t So Easy | Earth Wise

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There are initiatives around the world to plant millions of trees as a way to fight climate change.  Unfortunately, scientists have observed that many of these projects are ill-conceived and poorly managed.  Some have failed to grow any forests at all.

One such project was an attempt to plant a million mangrove seedlings in coastal mud on the Filipino island of Luzon in 2012.  Ten years later, less than 2% of the trees have survived.  The other 98% have died or have washed away.  The problem was that the site of the project was ecologically unsuited to mangroves because it is too waterlogged and there is no oxygen available except in a few sheltered spots.

In 2019, the Turkish government managed the planting of 11 million trees in 2,000 sites across the country.  A later survey found that 90% had died, although the government denies that assertion.

Many other projects have also had dismal results.  The causes of failure vary but include planting single species of trees that become vulnerable to disease, competing demands for land, changing climate, planting in areas not previously forested, and lack of ongoing care for the saplings including watering them.

Nobody is opposed to mass tree planting.  There is no anti-tree lobby.  But tree planting is sometimes a form of greenwashing.  It is great for public relations but unless it is done properly with appropriate planning, it can be a waste of effort and money.  The result can be a phantom forest that does nothing for the climate.

Forest planting can work if the social and environmental conditions are right, and if planting is followed by long-term monitoring and care of the trees.

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Phantom Forests: Why Ambitious Tree Planting Projects Are Failing

Photo, posted April 20, 2016, courtesy of the U.S. Navy / Mass Communication Specialist 2nd Class John Benson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate Change And Crabs | Earth Wise

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Globally, there are more than 6,000 species of crabs.  In Alaska’s waters alone, there are 18 species, including 10 that are commercially fished.  The perils of crab fishing in this region, including freezing temperatures, turbulent seas, and raising full pots that can weigh well over a ton, have been highlighted for many years in the reality TV series Deadliest Catch.        

One of those commercially-fished species is the Alaska snow crab.  Alaska snow crabs are a cold-water species found off the coast of Alaska in the Bering, Beaufort, and Chukchi Seas. 

In October, officials in Alaska announced that the upcoming winter snow crab season would be canceled for the first time ever due to a sharp population decline. While the number of juvenile snow crabs was at record highs just a few years ago, approximately 90% of snow crabs mysteriously disappeared ahead of last season.  Officials also canceled the Bristol Bay red king crab harvest for similar reasons for the second year in a row.

The closures dealt a severe blow to crab fishers in the region.  According to the Alaska Seafood Marketing Institute, Alaska’s crab fishing industry is worth more than $200 million. 

The canceled seasons also raise questions about the role of climate change in the snow crab population crash. While the causes of the decline are still being researched, scientists suspect that warmer temperatures are responsible.  Temperatures in the Arctic region have warmed four times faster than the rest of the planet. 

As the climate continues to change, the warming waters around Alaska may become increasingly inhospitable to snow crabs and other species.   

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Alaska’s Bering snow crab, king crab seasons canceled

Alaska cancels snow crab season for first time after population collapses

Photo, posted November 16, 2010, courtesy of David Csepp / NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Insects In A Changing Climate | Earth Wise

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Insects can be found in every environment on Earth and are critical components of many ecosystems.  They perform countless important functions, including aerating and fertilizing soil as well as pollinating flowers.  In fact, according to the USDA, 75% of the world’s flowering plants and about 35% of the world’s food crops depend on animal pollinators, the majority of which are insects, to reproduce.

According to a study published in the journal Nature earlier this year, the combination of climate change and intensive agriculture is having a profound impact on both the abundance and diversity of insects.  In regions where substantial warming had occurred and where land had been converted for intensive farming, insects were nearly 50% less abundant and more than 25% fewer species were observed.  Tropical regions were among those most at risk for heavy losses.

According to a new study recently published in the journal Global Change Biology, tropical insects will be even more susceptible to climate change than previously thought.  In a five-year study conducted in Peru, researchers from the Florida Museum of Natural History found that insect populations declined 50% following short periods of drought and following short periods of heavy rainfall.  Insect populations decreased after three months of dry weather, but also decreased after three months of exceptionally wet weather.   

Researchers have known that tropical insects don’t tend to do well when their habitats dry out.  But the researchers were surprised to discover that these insects were equally averse to increased precipitation.  Alarmingly, precipitation is expected to become more frequent and more intense as a consequence of the changing climate. 

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Tropical insects are extremely sensitive to changing climates

Photo, posted June 11, 2016, courtesy of Z. Leng via Flickr.

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