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Wildlife rebounding in Uganda

December 6, 2023 By EarthWise Leave a Comment

Wildlife making a comeback in Uganda

The numbers of elephants, rhinos, and other animals in Uganda’s nature preserves is steadily improving, reversing the trend of steady declines previously caused by poachers, wildlife traffickers, and conflict.

Between the 1960s and 1980s, political conflict and lawlessness in Uganda led to massive declines in some species as poaching, trafficking, and encroachment ran rampant.

Uganda’s population of over 700 northern white and eastern black rhinos was completely wiped out in the early 1980s by people hunting them for their horns.  A charity brought four rhinos in 2005 to a sanctuary called the Ziwa Rhino and Wildlife Ranch and, according to the Uganda Wildlife Authority, there are now 33 in the facility.

Increased conservation efforts have allowed the population of buffalos to increase 77% to over 44,000 since 1983.  The number of elephants has surged almost 300% to nearly 8,000 over that same time period.  There has also been an increase in the number of mountain gorillas in dense forests.

Over the years, the Ugandan government has brought in a string of conservation policies including lengthy jail terms for violations.  As a result, wildlife populations have been on a steady recovery.

It is typical to think about species in terms of how close to extinction they are, but the ultimate goal of conservation is to recover species.  This means not only gaining distance from extinction but also resuming a species’ role in its ecosystem and repopulating its former range.  Whether the wildlife in Uganda is achieving this status remains to be seen, but the trends are very positive.

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Uganda Sees Resurgence of Rhinos, Elephants, Buffaloes

Photo, posted September 15, 2014, courtesy of Rod Waddington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Megafires and ecosystems

November 15, 2023 By EarthWise Leave a Comment

Wildfires are a natural phenomenon.  They have occurred long before there were people around.  Ecosystems adapt to fires and some species can benefit from them or even depend upon them.  But in recent times, fires have been intensifying and increasing in frequency and they are beginning to outstrip nature’s ability to bounce back from them.

So-called megafires – ones that dwarf typical wildfires in size – have an immediate ecological toll.  They kill individual plants and animals that might have survived smaller fires. 

Over millennia, many species of plants and animals have evolved to adapt to periodic fires.  They are especially sensitive to smoke and take protective action in a timely fashion. Others take advantage of food sources that arise when trees burn.

But even species that capitalize on burned-out areas of forests require oases of healthy woodland for at least part of their activities.  When fires are too widespread, such oases are too few and far between.

Animals that survive fires must find food, water, and shelter in the aftermath.  And all air-breathing animals are going to be impacted by smoke exposure because the chemicals in smoke are toxic to them as well as to people.

In places like Canada’s Northwest Territories, repeated fires have transformed some forests, eliminating dominant tree species and replacing them with others whose light seeds were carried on the wind.

Scientists have estimated that increased global fire activity could push more than 1,000 threatened plant and animal species closer to extinction.  Changing fire patterns are transforming landscapes and utterly remaking ecosystems.

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How Megafires Are Remaking the World

Photo, posted December 19, 2022, courtesy of Brian Pippin/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind turbines and bats

October 31, 2023 By EarthWise Leave a Comment

How to reduce bat collisions with wind turbines

Collisions with wind turbines are one of the leading causes of bat mortality in North America and Europe.  Most bat fatalities are caused by bats colliding with the rotating blades of wind turbines.  Fatalities are highest during autumn migration and on nights with low wind speeds.

According to a recent study, land-based wind turbines kill as many as 880,000 bats a year and are wiping out so many threatened bats that some species may become endangered unless preventative action is taken.

The big challenge is that bat conservation experts and scientists don’t know how to stop or reduce turbine collisions.  They don’t really know why bats are interacting with turbines to the extent that they are.  Do turbines attract bats?  Do turbines’ bright lights or just their silhouettes stimulate an attraction response?

The U.S. Department of Energy has awarded $8 million to five research centers to develop strategies for deterring bats from wind turbines. 

One of these is Bat Conservation International, which is an organization whose mission is to accelerate research to address knowledge gaps in bat ecology and behavior and develop technologies and industry methods to reduce fatality of bats at wind farms.  Among the approaches to be tested is limiting the use of nighttime lighting on wind farms to make migrating bats less likely to fly through blades. 

Another team at Boise State University is designing ultrasonic noisemakers to scare off bats. 

In announcing the new program, the Department of Energy states that wind energy must be appropriately and responsibly sited, which includes the protection of wildlife and their habitats.

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Experts Seek to Spare Bats From Wind Turbine Collisions

Photo, posted January 10, 2013, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Spooky Reality | Earth Wise

October 23, 2023 By EarthWise Leave a Comment

According to the National Retail Federation, American consumers will spend a whopping $12.2 billion on Halloween this year, exceeding last year’s record of $10.6 billion.  A record number of people – 73% of Americans – will also participate in Halloween-related activities this year, up from 69% in 2022.  But it’s not just our wallets that take a beating. 

Halloween generates a frightening amount of waste.  Picture all those flimsy and often single-use costumes, polyester cobwebs, plastic-wrapped candy, mass-produced decorations, and so forth. Scary stuff!  Here are some simple tricks to make the holiday more sustainable this year. 

Invest in quality costumes.  Those mass-produced costumes leave the largest carbon footprint from Halloween.  They are often made from non-recyclable plastic and most end up in landfills by mid-November.   By renting, thrifting, swapping, or making your own costumes, many of the negative impacts of dressing up for the holiday can be avoided.

Find environmentally-friendly decorations and supplies.  For example, carve local pumpkins and either save the seeds and flesh to eat later, compost it, or feed it to animals.  Make your own spooky decorations.  If you do buy decorations, ensure that they are durable and reusable.  And use wicker baskets, old bags, or pillowcases when trick-or-treating.

Finally, purchase organic and fair trade candy if you’re able to do so.  Some of the largest candy manufacturers are major drivers of deforestation and species extinction around the globe due to their demand for sugar, palm oil, and cocoa beans.

Together, we can “green” Halloween.  

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Halloween Data Center

Photo, posted November 13, 2019, courtesy of Christian Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rivers And Climate Change | Earth Wise

October 11, 2023 By EarthWise Leave a Comment

Our planet is heating up.  Scientists have concluded that the changing climate is primarily the result of increased greenhouse gas emissions from human activities.  Some of the effects of global climate change include thawing permafrost, rising seas, intensifying storms and wildfires, and warming oceans.   

According to a new study led by researchers from Penn State University, rivers are warming and losing oxygen even faster than oceans.  The study, which was recently published in the journal Nature Climate Change, found that warming occurred in 87% and oxygen loss occurred in 70% of the nearly 800 rivers studied.

The research team projects that within the next 70 years some river systems, especially those in the American South, will experience such low oxygen levels that the rivers could “induce acute death” for some fish species and threaten the aquatic diversity of river ecosystems. 

The research team used artificial intelligence and deep learning to analyze water quality data from nearly 800 rivers across the U.S. and central Europe.  The researchers found that rivers are warming up and deoxygenating faster than oceans, which could have serious implications for both aquatic life and humans.

While climate change has led to warming and oxygen loss in oceans and lakes around the world, the researchers did not expect to find warming and deoxygenation in shallower, flowing rivers.  Since life in water depends on temperature and dissolved oxygen, the researchers hope this study serves as a wake up call.  Warming and deoxygenating rivers have significant implications for water quality and the health of aquatic ecosystems worldwide.

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Rivers are rapidly warming, losing oxygen; aquatic life at risk

Photo, posted June 2, 2017, courtesy of Francisco Anzola via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lithium In The Salton Sea | Earth Wise

October 2, 2023 By EarthWise Leave a Comment

The Salton Sea is a shallow, landlocked, extremely salty body of water in the southern end of California.  It was formed from an inflow of water from the Colorado River in 1905 in the aftermath of a collapse of a canal during spring floods.  At one time, it was a thriving tourist destination and site of real estate speculation.  It was also a crucial habitat for migratory birds and various aquatic species.

Over the past 20 years, the Salton Sea has become increasingly desiccated and polluted with agricultural runoff and waste.  Rising salinity and the shrinking water supply from the Colorado River has made it uninhabitable for many species.

Recently, the Salton Sea has attracted new attention because of untouched lithium deposits located beneath its shores.  The general area has acquired the moniker “Lithium Valley” and has become a place where major energy companies are exploring advanced mining techniques such as Direct Lithium Extraction (DLE).  This new technique enables lithium to be captured from brine deposits without resource-intensive open-pit mining or evaporation pond processes.

Lithium is crucial for making the batteries that power electric vehicles.  DLE mining has attracted large investments from billionaires like Warren Buffet, Bill Gates, and Jeff Bezos. 

Lithium mining has generated major controversies because of its potential to damage the environment.  Whether the new mining techniques can avoid these problems and tap into the potential resources near the Salton Sea remains to be seen.  According to experts, the aquifers near the Salton Sea hold enough lithium to supply close to 40% of the global demand.

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As Companies Eye Massive Lithium Deposits in California’s Salton Sea, Locals Anticipate a Mixed Bag

Photo, posted October 28, 2021, courtesy of Christian Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Cost Of Invasive Species | Earth Wise

September 27, 2023 By EarthWise Leave a Comment

According to a new report published by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services for the United Nations, invasive species introduced to new ecosystems around the world are causing more than $423 billion in estimated losses to the global economy every year.  These economic costs are incurred by harming nature, damaging food systems, and threatening human health.

According to the report, these costs have at least quadrupled every decade since 1970 and the estimates are actually conservative because it’s difficult to account for all of the effects of invasive species.

The report estimates that humans have intentionally or unintentionally introduced more than 37,000 species to places outside their natural ranges.  More than 3,500 of them are considered invasive because they are harmful to their new ecosystems.  Invasive nonnative species were a major factor in 60% of known extinctions of plants and animals.

Some species are relocated deliberately by the wildlife trade and international shipping.  Other plants and animals end up hitching a ride with ordinary travelers as they move about by car, boat, plane, or train. 

Invasions can damage human health.  Mosquitos that transmit diseases like malaria, dengue fever, and the Zika virus have become invasive around the world. The wildfires in Hawaii this summer were fueled by invasive nonnative grasses in a warming climate. 

Nearly every country in the world has agreed to participate in a sweeping agreement to preserve biodiversity and reduce invasive species.  It is an essential global goal.

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Invasive Species Are Costing the Global Economy Billions, Study Finds

Photo, posted June 2, 2022, courtesy of Sam Stukel (USFWS) via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Aphids And Monarchs | Earth Wise

September 15, 2023 By EarthWise Leave a Comment

Aphids are negatively impacting monarch butterfly populations

Last year, the monarch butterfly was officially designated as endangered by the International Union for Conservation of Nature.  Estimates are that the overall population of the species has dropped between 20% and 90% over the past several decades. 

The migratory western population of monarchs is at the greatest risk of extinction, having declined by as much as 99.9% between the 1980s and 2021.  Legal and illegal logging and deforestation to make space for agriculture and urban development has destroyed much of the butterflies’ winter shelter in Mexico and California and pesticides and herbicides throughout the butterflies’ range kills both the butterflies and the milkweed that their larvae feed on.

A new study by the University of Florida has found that aphids feeding on the milkweed that grows across the southern portions of the US causes the butterflies to lay fewer eggs on the plants and the caterpillars developing on those plants were slower to mature.  The study showed that monarch laid three times as many eggs on aphid-free plants as they did on aphid-infested plants.

For years, there have been efforts to plant milkweed in urban areas to support monarch populations.  However, aphids and other insect pests often reach high densities on plants in urban settings. 

The researchers are advising home gardeners in the southern U.S. who want to conserve monarch butterflies to make use of safe techniques to limit aphid populations such as insecticidal soap.  This may not always be an option and the researchers are investigating other options to keep aphids at low levels that aren’t harmful to monarchs.

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Aphids make tropical milkweed less inviting to monarch butterflies, study finds

Photo, posted October 12, 2018, courtesy of Renee Grayson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Top Fish Predators And Climate Change | Earth Wise

September 12, 2023 By EarthWise Leave a Comment

Climate change is taking its toll on forests, farms, freshwater sources, and the economy, but ocean ecosystems remain the epicenter of global warming.  In fact, oceans have absorbed more than 90% of the excess heat from greenhouse gas emissions since the 1970s.

As a result, many marine fish species are responding to ocean warming by relocating towards the poles.  According to new research recently published in the journal Science Advances, climate change is causing widespread habitat loss for some of the ocean’s top fish predators, driving these species northward.

The research team studied 12 species of highly migratory fish predators, including sharks, tuna, and billfish, such as marlin and swordfish, inhabiting the Northwest Atlantic Ocean and the Gulf of Mexico.  These two regions are undergoing rapid changes in sea surface temperatures, and are among the fastest warming ocean regions on earth.

The research, which was led by researchers from Woods Hole Oceanographic Institution in Massachusetts, with collaboration from San Diego State University, NOAA, and several other U.S. institutions, found that most species will encounter widespread habitat losses by 2100.  Some species could lose upwards of 70% of suitable habitat by that year.  Areas offshore of the Southeast United States and Mid-Atlantic coasts were identified as likely hotspots of multi-species habitat loss. 

According to the researchers, strategies for managing fish have historically been static. But marine systems need to be treated as dynamic and changing.  This study helps provide the scientific data needed for marine conservation and fisheries management efforts.

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Top fish predators could suffer wide loss of suitable habitat by 2100 due to climate change

Photo, posted March 18, 2015, courtesy of Kenneth Hagemeyer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Protecting The Amazon Rainforest | Earth Wise

September 5, 2023 By EarthWise Leave a Comment

The Amazon rainforest absorbs one-fourth of all the carbon dioxide absorbed by the land of the Earth.  It is by far the world’s largest rainforest, bigger than the next two largest – in the Congo Basin and Indonesia – combined.  Nearly two-thirds of it is found in Brazil but the more than 2 million square miles of rainforest includes portions in 8 countries.

The amount of carbon dioxide absorbed by the Amazon rainforest is 30% less today than it was in the 1990s as a result of deforestation, to a great extent driven by cattle ranching as well as other agricultural activities.

In early August, the leaders of the eight countries that are home to the Amazon River basin agreed to work together to conserve the rainforest.  The agreement, called the Belém Declaration, provides a roadmap to stave off the rampant deforestation. 

The agreement provides coordination between the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Suriname, and Venezuela to establish law enforcement to combat illegal mining and logging as well as to pool development funds for conservation and sustainable employment.  Despite the unity portrayed at the meeting, many of the governments in South America are in a precarious position because of various economic and political struggles

Apart from its critical climate impact, the Amazon rainforest is a haven for biodiversity and further deforestation would be disastrous for tens of thousands of species and could transform it into a net emitter rather than absorber of greenhouse gases.  Some parts of the region have already reached that point.

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Amazon Countries, Led by Brazil, Sign a Rainforest Pact

Photo, posted October 17, 2016, courtesy of Yeoboya via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Endangered Plants And The Changing Climate | Earth Wise

August 31, 2023 By EarthWise Leave a Comment

Plants are a critical resource because of the countless ways they support life on Earth. Plants release oxygen into the atmosphere, absorb carbon dioxide, and provide food and habitat for humans and wildlife.  Plants are also used to produce fibers, building materials, and medicines. 

Plants form the backbone of natural ecosystems, and absorb about 30% of all the carbon dioxide emitted by humans each year.  But plants are struggling to adapt in a human-dominated world.  Even though they are easier and cheaper to protect than animals, plants are often overlooked in conservation efforts.

Ironically, conservation efforts appear to be overlooking a key threat to endangered plants.  According to a new study led by researchers from Penn State University, all plants and lichens listed as endangered under the Endangered Species Act are sensitive to climate change, but there are few plans in place to address that threat directly. 

The threat that climate change poses to endangered plants and lichens had not been thoroughly evaluated in more than a decade.  In the study, which was recently published in the journal PLOS Climate, the research team adapted existing assessment tools used to examine the threat of climate change for wild animals and applied them to 771 endangered plant species.  The researchers found that all endangered plant and lichen species are at least slightly threatened by climate change, and little is being done to protect the listed species from that threat.

The researchers hope their findings will be used to aid future conservation planning.  After all, plants can live without humans, but humans cannot live without plants.

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Climate change threatens 771 endangered plant and lichen species

Photo, posted June 12, 2014, courtesy of Mark Freeth via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Beaver Believers | Earth Wise

August 18, 2023 By EarthWise Leave a Comment

Believing in beavers as ecosystem engineers

Beavers are ecosystem engineers based on their ability to construct dams and create ponds.  By doing so, they create wetland habitat for other species.  They create biodiversity by allowing plant species to emerge in new places as they clear out existing trees and other plants.  Beavers improve water quality and their dams store water during droughts.  Their handiwork minimizes flood risk and mitigates flooding impacts.

Before beavers were widely trapped, there were beaver dams just about everywhere in the American west.  Now beaver rewilding is trying to restore many western ecosystems. In places like Idaho, ranchers have gone from seeing beavers as a nuisance to actually recruiting them onto their land.  One cattle rancher began stream restoration on his land with beaver rewilding in 2014.  By 2022, he was a firm “beaver believer”.  There are now over 200 beaver dams along Birch Creek near Preston, Idaho, and the stream now flows 40 days longer into the year.

NASA has established a team to investigate the extent to which beavers can have an outsized and positive impact on local ecosystems.  The team is using NASA’s Earth Observation satellites to observe the effects beavers are having.  Satellites can collect data from large areas and can pass over the same areas regularly and across seasons.  The goal is to support people on the ground who are implementing beaver rewilding efforts to increase water availability and to increase habits for fish and other species.  NASA’s project will run through 2025 and it plans to expand it to other states with similar terrain and water management strategies.

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Researchers Become “Beaver Believers” After Measuring the Impacts of Rewilding

Photo, posted February 23, 2021, courtesy of Deborah Freeman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Global Aquaculture And Environmental Change | Earth Wise

August 9, 2023 By EarthWise Leave a Comment

Climate change threatens viability of aquaculture

Blue foods are fish, invertebrates, algae, and aquatic plants that are captured or cultured in freshwater and marine ecosystems.  They include approximately 2,200 species of fish, shellfish, plants and algae as well as more than 500 species farmed in freshwater.  Blue foods play a central role in food and nutrition security for billions of people, and are a cornerstone of the livelihoods, economies, and cultures of many communities around the world.

But many of the world’s largest aquatic food producers are highly vulnerable to human-induced environmental change.  According to a new paper recently published in the journal Nature Sustainability, more than 90% of global blue food production is at risk from environmental changes, with top producers like the United States, Norway, and China facing the biggest threat.  Alarmingly, the research also found that some of the highest-risk countries in Asia, Latin America and Africa demonstrate the lowest capacity for adaptation. 

The paper is the first-ever global analysis of environmental stressors impacting the production quantity and safety of blue foods. A total of 17 anthropogenic stressors were surveyed, including rising seas and temperatures, ocean acidification, changes in rainfall, algal blooms, pollution, and pesticides. 

The research is one of seven scientific papers published by the Blue Food Assessment as part of a global effort to inform future aquatic food sustainability. 

The report calls for more transboundary collaboration and for a diversification of blue food production in high-risk countries to cope with the impact of environmental change. 

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Vulnerability of blue foods to human-induced environmental change

New research finds that more than 90% of global aquaculture faces substantial risk from environmental change

Photo, posted December 30, 2014, courtesy of NOAA’s National Ocean Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cryo Conservation | Earth Wise

August 2, 2023 By EarthWise Leave a Comment

Recent studies have shown that there has been a 69% decline in global animal populations since 1970.  There is a biodiversity crisis in the world.  In the face of this situation, there is a growing interest in using cold storage to preserve genetic samples taken from animals threatened with extinction.

Just as egg-freezing is used to preserve human fertility for a later date, the cryogenic freezing of genetic material from animals could be important in reducing species extinctions.  Living cell banks – also known as cryobanks – could preserve genetic materials from animals that include skin cells, embryos, semen, and live tissues.  These materials could be cultured and used for various applications including DNA extraction, assisted reproduction, ensuring genetic diversity in animal populations, and potentially reintroducing species back into their natural habitats.

There is a facility called the Frozen Zoo at the San Diego Wildlife Alliance which has genetic material from 965 different species, including 5% of the vertebrates currently listed as threatened on the IUCN Red List.  Further sampling from zoos and aquariums could increase that representation to almost 17%.

Genetic samples of 50% of the species currently listed as extinct in the wild are already represented in the Frozen Zoo.  Further sampling from the zoological community could increase this number to 91%.  This could provide a critical lifeline for these species that are on the brink of extinction.  As wildlife populations continue to decline around the world, it is more critical than ever to collect and preserve genetic samples from threatened species.

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Cryo conservation – a cool solution to saving species from extinction

Photo, posted September 30, 2018, courtesy of Andy Morffew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Ocean Oxygen Levels And The Future Of Fish | Earth Wise

June 23, 2023 By EarthWise Leave a Comment

How oxygen levels in the ocean will impact the future of fish

Climate change is creating a cascade of effects in the world’s oceans.  Not only are ocean temperatures on the rise, but oceans are becoming more acidic, and oxygen deprived.  The warming temperatures and acidification have grabbed headlines and prompted academic research. Declining oxygen levels have not garnered as much attention.  But they spell bad news for fish.

Oxygen levels in the world’s oceans have dropped over 2% between 1960 and 2010 and are expected to decline up to 7% over the next century.  There are places in the northeast Pacific that have lost more than 15% of their oxygen.  There are a growing number of “oxygen minimum zones” where big fish cannot survive but jellyfish can.

Oceans are losing oxygen for several reasons.  First, warmer water can hold less dissolved gas than colder water.  (This is why warm soda is flatter than cold soda.)  Deeper in the ocean, oxygen levels are governed by currents that mix oxygen-rich surface water from above.  Melting ice in the warming polar regions add fresh, less-dense water that resists downward mixing in key regions.  Finally, increasing amounts of ocean bacteria in warming waters gobble up oxygen creating dead zones in the ocean.

In many places, fish species that cannot cope with lower oxygen levels are migrating from their usual homes, resulting in a decline in species diversity.  Our future oceans – warmer and oxygen-deprived – will not only hold fewer kinds of fish, but also smaller fish and even more greenhouse-gas producing bacteria.   

Climate change is bad news for fish and for the more than 3 billion people in the world who depend on seafood as a significant source of protein.

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As Ocean Oxygen Levels Dip, Fish Face an Uncertain Future

Photo, posted January 10, 2022, courtesy of Willy Goldsmith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate Change And Species Tipping Points | Earth Wise

June 22, 2023 By EarthWise Leave a Comment

In climate science, tipping points are critical thresholds that, once crossed, lead to large and often irreversible changes in the climate system. For example, surpassing a 1.5 degree C rise in global warming has long been considered a tipping point for the planet. 

According to a new study led by researchers from University College London, climate change will abruptly push species over tipping points as their geographic ranges reach unforeseen temperatures. 

In the study, which was recently published in the journal Nature Ecology and Evolution, the research team analyzed data from more than 35,000 species of animals and seagrasses from every continent and ocean basin, alongside climate projections up to 2100.  The researchers found a consistent trend:  for many animals, the thermal exposure threshold will be crossed for much of their geographic range within the same decade. 

The thermal exposure threshold is defined as the first five consecutive years where temperatures consistently exceed the most extreme monthly temperature experienced by a species across its geographic range over recent history. 

The researchers also found that the extent of global warming will make a big difference for animals.  If the planet warms by just 1.5°C, 15% of species studied will be at risk of experiencing unfamiliarly hot temperatures across at least 30% of their current  geographic range in a single decade.  But this figure will double to 30% of species at 2.5°C of warming.

Since their data provides an early warning system, the researchers hope that their findings will help species conservation efforts. 

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Climate change to push species over abrupt tipping points

Photo, posted May 27, 2017, courtesy of Sarah Lemarié via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Chasing The Ivory-Billed Woodpecker | Earth Wise

June 13, 2023 By EarthWise Leave a Comment

The ivory-billed woodpecker is or was the largest woodpecker in the United States. The last unassailable sighting of the bird was in 1944.  Since then, there have various reports of glimpses of the bird or of hearing its distinctive sounds.  But there has not been anything resembling proof that the bird still exists.

Despite this, the ivory-billed woodpecker has been legally protected under the Endangered Species Act.  There has been a proposal to end that protection and formally declare the species extinct.  Because of the controversy surrounding the bird, a final ruling on its status has been repeatedly delayed by the US Fish and Wildlife Service.

Very recently, a peer-reviewed study in the journal Ecology and Evolution makes the case that the ivory-billed woodpecker still exists and that it is premature to declare it extinct.  The study cites visual encounters by expert observers, audio recordings, tree-damage, and rather grainy video evidence.  The authors claim that there is intermittent but repeated presence of birds that at least look and behave like ivory-billed woodpeckers.

One might ask:  why does it matter whether this bird is declared extinct or not?  The answer is that there are limited federal funds for conservation efforts, and they should be spent on saving genuinely endangered species and habitats.  The authors of the new study say that removing federal protection would be bad for any remaining ivory bills, which may be living in some swampy old-growth forests in Louisiana.  Other scientists consider conservation resources expended on the ivory-billed woodpecker to be chasing a ghost.

As is the case for several other notorious objects, one really clear photograph of an ivory-billed woodpecker could solve a long-standing mystery.

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A Vanished Bird Might Live On, or Not. The Video Is Grainy

Photo, posted October 19, 2014, courtesy of James St. John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Can All Plant Species Survive? | Earth Wise 

June 9, 2023 By EarthWise Leave a Comment

Many animal populations around the world are struggling and people are mostly to blame.  Species are declining because of all sorts of things including changes in land and sea use, pollution, invasive species, and climate change.

Like many animal species, plants are also struggling to adapt to a human-dominated world.  Plants provide the planet with food, oxygen, and energy, and are used to produce fibers, building materials, and medicines.  Even though plants are easier and cheaper to protect, they are often overlooked in conservation efforts. 

According to a paper recently published in the journal Trends in Plant Science, preventing all future land plant extinctions across the globe is possible with the right approaches.  The author of the paper, Richard Corlett of the Xishuangbanna Tropical Botanical Garden in China, writes that “if zero extinction is potentially achievable for plants, a less ambitious target would be inexcusable.” 

According to the paper, one big barrier in plant conservation is the lack of trained specialists, especially in tropical areas where there is a backlog of unidentified species.  It’s likely that many “dark extinctions,” which is when species slip away without us knowing they existed, have already occurred.

Another roadblock in preventing plant extinctions is information access, which can be solved by building an online “metaherbarium.”  This collaborative database would link digitized records from herbarium specimens with photographs, status assessments, and recovery plans.

Finally, the creation of “microreserves” – which are tiny pieces of protected land designed to get around space constraints – would further contribute to effective conservation of targeted plant species. 

Zero plant extinctions should be the goal.   

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‘Zero plant extinction’ is possible, says plant ecologist

Photo, posted May 16, 2008, courtesy of Andrew Otto via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Shrinking Birds | Earth Wise

June 5, 2023 By EarthWise Leave a Comment

A new study by researchers at Yale University looks at the way bird morphology is changing in response to the warming climate.  As temperatures rise, birds’ bodies are growing smaller, but their wings are growing longer.

In the study, published in the Proceedings of the National Academy of Sciences, the scientists analyzed two independently collected datasets containing 40 years of morphology changes in 129 bird species comprising 52 migratory species in North America and 77 South American species.

In both datasets, similar changes were observed over the 40-year period.  The overall trend makes sense given that being smaller and having longer wings both would help birds to stay cool in warmer weather.  What was less obvious was that the changes to the birds were much greater among the smallest bird species.

One possible explanation is that smaller species tend to reproduce on a shorter time scale and therefore evolve more quickly.  However, the study found no link between generation length and the changes in body size.

Another possible explanation is that smaller species tend to have larger populations, which means there is a greater chance of having individuals with desirable new traits that can get passed on.  But the scientists found no link between population size and shifts in body size either.

At this point, it is unclear why smaller birds are shrinking more.  More research is needed to figure out why larger birds are slower to adapt to climate change.  In general, larger species of animals have an increased risk of extinction.  This new research suggests that larger body size exacerbates extinction risk by limiting the ability for birds to adapt to the changes we are making to the climate.

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Birds Are Shrinking as the Climate Warms — and Small Birds Are Shrinking Faster

Photo, posted October 30, 2018, courtesy of N. Lewis / National Park Service via Flickr.

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Plastic Eating Fungus | Earth Wise

May 26, 2023 By EarthWise Leave a Comment

Researchers exploring the use of fungi to break down plastic

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

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