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Coexisting birds and solar energy

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Floating photovoltaic systems – known as floatovoltaics – are becoming increasingly popular.  These are arrays of solar panels installed over artificial water bodies such as irrigation ponds, wastewater treatment plants, and reservoirs.  These projects maximize the space for producing clean energy while not taking up natural lands.

Wherever there are bodies of water, there are waterbirds.  A recent study by researchers at the University of California, Davis looked at the potential impact of floating solar projects on birds and other wildlife. 

Birds face many threats from habitat loss, climate change, pollution, and disease.  Many bird populations are in decline.  So, it is important to consider the effects of floating solar projects on birds. 

The researchers have observed birds resting on floating solar structures before dawn, birds jockeying for favorable sites on the structures, and some nesting under the panels.  These are positive interactions.  On the other hand, it is possible that pollutants could be released or leached from floating solar infrastructure.  Such risks must be mitigated.

Floating solar on irrigation ponds and reservoirs can reduce evaporation and reduce algae growth, which benefits both humans and wildlife.

The researchers will continue to monitor bird behavior at floating solar installations using expertise in ecology and energy system science to identify risks and solution pathways so that negative impacts are avoided, and potential ecological benefits are realized.  It is important that as floating solar continues to become more popular, it and waterbirds can coexist.

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Helping Birds and Floating Solar Energy Coexist

Photo, posted February 28, 2019, courtesy of Renee Grayson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Living in a warming world

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As global temperatures rise due to increased greenhouse gas emissions, communities around the world face more frequent and intense heatwaves, droughts, and extreme weather events. These growing climate pressures not only strain infrastructure and natural resources, but also play a critical role in shaping where people live. 

Recent projections from the First Street Foundation, which analyzes climate risks across the United States, highlight just how significant these shifts could be. In Sacramento County, California, rising flood risks, declining air quality, and soaring insurance costs could lead to a population decline of up to 28% by 2055. The risk assessment also projects that Monmouth and Ocean counties in New Jersey could each lose more than 30% of their populations. And Fresno County, California, could see nearly half of its residents relocate due to mounting climate-related pressures.

Urban areas like cities, towns, and suburbs are particularly vulnerable to the impacts of climate change.  Cities become significantly hotter due to the abundance of heat-absorbing surfaces and lack of green spaces, which intensifies heatwaves, worsens conditions for vulnerable populations, and may ultimately force some people to move.

Addressing these challenges requires a combination of climate solutions focused on both mitigation and adaptation. Solutions like expanding green infrastructure with urban parks and green roofs, and promoting sustainable development through energy-efficient buildings and transit-friendly design could all play a vital role in strengthening climate resilience.

As the planet warms, where we live – and how we live there – is rapidly being redefined.

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The 12th National Risk Assessment

Solar on farmland

Photo, posted May 15, 2013, courtesy of Germán Poo-Caamaño via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The oceans are warming faster

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A new study has shown that the rate of ocean warming has more than quadrupled over the past 40 years.  The study, by researchers at the University of Reading in the UK, helps to explain why there have been unprecedented ocean temperatures in 2023 and 2024.

Global ocean temperatures hit record highs for 450 days straight in 2023 and early 2024.  Some of this unusual warmth came from the El Niño that was taking place at the time, but the rest of the increased temperature came from the sea surface warming up more quickly over the past 10 years than in previous decades.  In the late 1980s, ocean temperatures were rising at a rate of 0.06 degrees Celsius per decade.  According to the recent research, they are now increasing at 0.27 degrees per decade.

The acceleration of ocean warming is driven by growth in the Earth’s energy imbalance, meaning that more energy from the sun is being absorbed by the Earth than is escaping back into space.  This energy imbalance has roughly doubled since 2010 as a result of two factors:  increasing greenhouse gas concentrations in the atmosphere and reductions in the Earth’s albedo.

Earth’s albedo, the measure of how much sunlight is reflected back into space, has been declining since the 1970s, primarily due to the decrease in snow and ice cover, especially in the Arctic. 

The overall rate of ocean warming observed over recent decade is likely to only increase.  This underscores the urgency of reducing fossil fuel burning to avoid even more rapid temperature increases in the future.

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Ocean-surface warming four times faster now than late-1980s

Photo, posted January 18, 2007, courtesy of Alexey Krasavin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The human impact on biodiversity

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Biodiversity is under threat.  More and more plant and animal species are disappearing and humans are to blame.  Humans cause biodiversity loss through habitat destruction, invasive species, pollution, direct exploitation, and climate change, all of which are significantly influenced by human activities.

But until now, drawing broad conclusions about human impacts on biodiversity has been difficult because a clear, global overview of how human activity affects nature across all species did not exist. Most studies have focused on specific places, impacts, or time periods.

To fill these research gaps, a research team from the University of Zurich in Switzerland and the Swiss Federal Institute of Aquatic Science and Technology conducted an unprecedented synthesis study.  The researchers compiled data from around 2,100 studies that compared biodiversity at almost 50,000 sites affected by humans with similar places that hadn’t been affected by humans. 

The synthesis study, which was recently published in the journal Nature, found humans are having a highly detrimental impact on biodiversity worldwide.  In fact, not only is the number of species declining, but the composition of species communities is also changing.  On average, the number of species at impacted sites was almost 20% lower than at unaffected sites.

The study, which is one of the largest ever conducted on this topic, highlights the widespread negative impact of human activities on nature, and emphasizes the need to consider all forms of life when assessing biodiversity loss. 

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The Devastating Human Impact on Biodiversity

Photo, posted November 19, 2014, courtesy of Green Mountain Girls Farm via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The American butterfly census

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There has been a great deal of interest in the plight of monarch butterflies in this country.  Monarchs’ population and migratory habits are closely watched, and many people have been planting milkweed in their gardens to help their caterpillars.  But other butterfly species have received much less attention despite the fact that many butterfly populations are in decline.

A groundbreaking new study has provided comprehensive answers about the status of butterflies in America.  Over the past 20 years, the contiguous US has lost 22 percent of its butterflies.

The study is based on over 12 million individual butteries counted in 77,000 surveys across 35 monitoring programs from 2000 to 2020.  Three hundred forty-two butterfly species in total were analyzed.  Thirty three percent showed statistically significant declines while less than 3% displayed statistically significant increases.  Overall, 13 times as many species decreased as increased.

Why are butterfly populations crashing?  Experts point to a combination of factors:  habitat loss as land in converted for agriculture or development, climate change, and pesticide use.  It is not clear which factor is most important and may well vary by location.  Pesticide use – especially neonicotinoids – has been shown to play a particularly lethal role in studies. 

Insects including butterflies play a huge role in supporting life on earth.  They pollinate plants, feed birds and many other creatures in the food web.  Nature collapses without them.  And butterflies are clearly in trouble.

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See How Butterflies Are Surviving, or Not, Near You

Photo, posted August 9, 2016, courtesy of Rachel Larue/Arlington National Cemetery via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Polar bear population decline

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Researchers from the University of Toronto have directly linked the population decline in polar bears living in Canada’s Western Hudson Bay to climate change.  Between 1979 and 2021, the polar bear population in this region has declined by nearly 50%.

The monitoring data over this period shows that the average size of polar bears has declined, the size of cub litters has dropped, and cub survival rates are reduced.

The primary factor is the declining amount and duration of sea ice.  When there is less ice, bears have less feeding time and less energy overall.  The loss of sea ice means that bears spend less time hunting seals and more time fasting on land.  The lack of food leads to reduced reproduction, cub survival, and, ultimately, population decline. 

The average body mass of adult females has dropped by 86 pounds and of cubs by 47 pounds.  With shorter hunting periods and less food, mothers produce less milk.  Not only have cub litter sizes dropped over the monitoring period, but mothers are keeping their cubs longer because they are not strong enough to live on their own.  The bottom line is that the survival of cubs directly impacts the survival of the population.

Western Hudson Bay is considered to be a bellwether for polar bear populations globally.  It is one of the southernmost populations of polar bears and it has been monitored for a long time.  With the Arctic warming at a rate four times faster than the global average, polar bear populations in other Arctic regions are likely to be experiencing similar declines. 

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Polar bear population decline the direct result of extended ‘energy deficit’ due to lack of food

Photo, posted October 23, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Saving the Great Salt Lake

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For many years, scientists have warned that the Great Salt Lake in Utah is headed toward a catastrophic decline.  While the size of the Great Salt Lake fluctuates naturally with seasonal and long-term weather patterns, the lake has been experiencing significant and steady declines for decades.  In fact, the Great Salt Lake has lost more than 15 billion cubic yards of water over the past three decades, and it’s getting shallower at the rate of four inches a year. 

This reduction is primarily due to excessive water diversions from rivers and streams that feed into the lake for agricultural, industrial, and municipal use. These diversions, combined with prolonged drought and rising temperatures due to climate change, have significantly reduced the lake’s water level. 

According to a new study led by researchers from Oregon State University, 62% of the river water bound for the Great Salt Lake is diverted for human use, with agricultural activities responsible for nearly three-quarters of that percentage.  The analysis, which was recently published in the journal Environmental Challenges, found that reducing irrigation is necessary to save the lake. 

In order to stabilize and begin refilling the lake, the research team proposes cutting human water consumption in the Great Salt Lake’s watershed by 35%.  The researchers emphasize that farmers and ranchers facing income losses from using less water would require taxpayer-funded compensation.

The Great Salt Lake is a biodiversity hotspot, sustaining more than 10 million migratory birds.  The lake also directly supports 9,000 jobs and fuels $2.5 billion in economic activity annually. 

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Reducing irrigation for livestock feed crops is needed to save Great Salt Lake, study argues

Photo, posted January 14, 2024, courtesy of Olaf Zerbock via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Climate change and an iconic Florida bird

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The Florida scrub-jay is a medium-sized bird native to Florida, known for its striking blue plumage and distinctive call. It is the only bird species that is entirely endemic to Florida, found mainly in the scrubby, sandy habitats of the central and southern part of the Sunshine State.

But extensive development, habitat fragmentation, and habitat degradation have caused the scrub-jay population to decline significantly over the past century. 

Another threat facing the Florida scrub-jay is climate change.  According to a new study by researchers from the Archbold Biological Station and the Cornell Lab of Ornithology, warmer winters driven by climate change are causing Florida scrub-jays to nest one week earlier than they did in 1981.  This seemingly innocuous change has reduced the number of offspring raised annually by 25% since 1981. 

The research team examined 37 years of data to assess the impacts of warming on reproductive efforts.  From 1981 to 2018, the average winter temperature at Archbold Biological Station in Florida increased by 2.5 degrees Fahrenheit.  Despite increases in the number of nests built and eggs laid over the longer breeding season, Florida scrub-jays are not producing more young. 

The researchers hypothesize that warmer temperatures make the nests susceptible to predation by snakes for a longer period of the Florida spring than in the past.  The findings, which were recently published in the journal Ornithology, suggest that climate change could dampen the success of conservation efforts for this threatened species.

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Long-term study reveals warming climates threaten Florida scrub-jay

Florida Scrub-Jay

Photo, posted October 15, 2018, courtesy of Judy Gallagher via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Emissions and the Great Salt Lake

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The Great Salt Lake in Utah has been described as a puddle of its former self.  The lake’s size fluctuates naturally with seasonal and long-term weather patterns, but the lake has been experiencing decline for decades as Utahans take water out of the rivers and streams that once fed the lake.  Over recent decades, the lake has lost 73% of its water and 60% of its surface area.

For years, scientists and environmental leaders have warned that the Great Salt Lake is headed toward a catastrophic decline.  Recent research has found that the lake’s desiccating shores are becoming a significant source of greenhouse gas emissions.  Scientists have calculated that the dried-out portions of the lakebed released about 4.1 million tons of carbon dioxide and other greenhouse gases in 2020.

The recent study, published in the journal One Earth, suggests that the Great Salt Lake – which is largest saltwater lake in the Western Hemisphere – as well as other shrinking saline lakes around the world could become major contributors of climate-warming emissions.

The shrinking back of the water has exposed a dusty lakebed that is laced with arsenic, mercury, lead, and other toxic substances.  Some are naturally occurring, and others are the residue of mining activity in the region.  These substances threaten to increase rates of respiratory conditions, heart and lung disease, and cancers.

As the lake shrinks, it is becoming saltier and uninhabitable to native flies and brine shrimp and may increasingly become unable to support the 10 million migratory birds and wildlife that frequent it.

The new research about greenhouse gas emissions just adds to a dire list of environmental consequences brought on by the lake’s steep decline.

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Shrinking Great Salt Lake Becoming Source of Heat-Trapping Gas

Photo, posted January 20, 2020, courtesy of Matthew Dillon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The slippery slopes of the ski industry

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According to the National Oceanic and Atmospheric Administration, snowfall is declining globally as temperatures warm because of human-caused climate change.  Less snow threatens to reinforce global warming, and to disrupt food, water, and livelihoods for billions of people.   

According to new modeling by researchers from Protect Our Winters Australia and The Australian National University, the ski industry in Australia is at risk of major disruptions and shorter seasons if climate change continues unabated.  The researchers found the average ski season across all resorts in Australia will be 44 days shorter by 2050 under a mid-greenhouse gas emissions scenario, and 55 days shorter under a high-emissions scenario.

But the research team also revealed that the Australian ski industry would fare significantly better if decisive action is taken to reduce climate pollution.  In fact, under a low-emissions scenario, the ski season would be 28 days shorter by 2050, before starting to improve by 2080 if emissions are kept down.

However, if decisive climate action isn’t taken, the researchers warn some ski resorts in Australia may be forced to close for good.  But this threat isn’t unique to Australia. 

In fact, according to a study recently published in the journal PLOS ONE, 13% of ski areas around the world are predicted to lose all natural snow cover under the high-emissions scenario by 2071-2100 – relative to their historic baselines. 

The future losses of ski areas around the world will be significant if global emissions continue unchecked.

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Climate crisis puts Australia’s ski industry on slippery slope, but not all hope is lost

“Our Changing Snowscapes” Report Released

The future is likely less skiable, thanks to climate change

Photo, posted June 6, 2018, courtesy of Clement Tang via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Declining pollinator populations

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Scientists have been sounding the alarm on the global struggle of pollinators for decades.  Many recent studies have highlighted alarming declines in pollinator populations, sparking concern about the potential negative impacts on ecosystems and agriculture.  Habitat loss, invasive species, and climate change are some of the factors linked to the population declines. But most pollinator research has focused on well-studied species in easily-accessible regions.

In a new study recently published in the journal PLOS One, a research team led by Northern Arizona University compiled data on four major families of bees and butterflies to create species distribution models, allowing them to assess changes over time and space across North America.

The researchers confirmed that bee and butterfly populations are declining in major regions of North America due to ongoing environmental changes, and found that significant gaps in pollinator research limit the ability to protect these species. 

The highest species richness was found along North America’s West Coast –  especially in California. But the models showed a decline in species richness over the past century in western North America.  In contrast, the research team found disproportionate increases in eastern North America.

Comparisons with climate data indicate that the pollinator population changes are at least partly due to the impacts of climate change, including prolonged drought and habitat degradation. 

The study identifies regions of declining populations where officials can prioritize conservation efforts, and highlights how improved monitoring methods could address the knowledge gaps on pollinator populations.

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Bee and butterfly records indicate diversity losses in western and southern North America, but extensive knowledge gaps remain

Bees and butterflies on the decline in western and southern North America

Photo, posted April 3, 2017, courtesy of Tracie Hall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fireflies are in decline

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If you are seeing fewer fireflies each year, you’re not alone.  Like many insects, firefly populations are in decline.  A new study by researchers from the University of Kentucky, Bucknell University, Penn State University, and the USDA has shed some light on the precarious situation facing firefly populations across North America. 

The research team used a mix of field surveys from citizen scientists and advanced machine learning techniques to analyze more than 24,000 surveys from the Firefly Watch citizen science initiative.  The study, which was recently published in the journal Science of the Total Environment, identified the factors likely responsible for the declines in firefly populations. 

The research team found that fireflies are sensitive to various environmental factors, from short-term weather conditions to longer climatic trends.  Fireflies thrive in temperate and tropical climates.  As global temperatures rise, these conditions become less predictable and less hospitable.

Light pollution is another threat to fireflies.  Artificial light at night – from things like street lights and billboards – is particularly disruptive to fireflies as it interferes with their bioluminescent communication essential for mating.

Urban growth, including buildings, roads, and sidewalks, poses another significant threat to fireflies by overtaking their natural habitats and decreasing available breeding areas. 

Additionally, certain agricultural practices seem to contribute to the decline of fireflies. 

According to the research team, reducing light pollution, preserving natural habitats, and implementing wildlife-friendly agricultural practices are conservation measures that could help mitigate the decline of fireflies. 

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Fading lights: Comprehensive study unveils multiple threats to North America’s firefly populations

Photo, posted July 12, 2021, courtesy of Bruce Hallman/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Good owls and bad owls

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In the forests of the Pacific Northwest, spotted owls have been the subject of environmental concern for more than 30 years.  Over the past 20 years, northern spotted owl populations have declined by up to 80% as the birds have faced marginalized territories and increasing numbers of wildfires.  Only about 3,000 of them remain on federal lands.  Spotted owls are picky eaters and are not very adaptable.

The barred owl, a larger and more ornery species, has been moving in on spotted owl turf for 50 years, competing for food and space, and out-reproducing them and chasing them out of their nesting spots.

A last-ditch effort to rescue the northern spotted owl from possible extinction has been proposed by the U.S. Fish and Wildlife Service.  The plan would be to eradicate up to half a million barred owls over the next 30 years in Washington, Oregon, and Northern California.  The owls would be dispatched using cheap and efficient methods, such as shotguns.

The concept of killing off vast numbers of barred owls is awful, and nobody likes the idea.  However, other strategies have failed, and time is running out.  The only way to preserve the northern spotted owl is to protect and increase its habitat and have fewer barred owls.

To say that the proposed plan is controversial is a massive understatement.  A coalition of 75 wildlife and animal welfare organizations described it as a “colossally reckless action.”

A central issue in the debate is whether humans are responsible for this situation and should try to rectify it or, despite our desire to protect the spotted owl, we should just let nature take its course.

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They Shoot Owls in California, Don’t They?

Photo, posted April 4, 2022, courtesy of Kyle Sullivan / BLM via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The end of coal in New England

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The last two coal-fired power plants in New England are scheduled to close by 2025 and 2028.  The New Hampshire-based plants are operated by Granite Shore Power.  The Schiller Station plant began operations in 1949 and the Merrimack Station was built in the 1960s.

Granite Shore Power has come to an agreement with the Environmental Protection Agency as part of a settlement of lawsuits by the Conservation Law Foundation and the Sierra Club.  The two power plants were the subject of a five-year legal battle waged by clean energy advocates

Granite Shore Power intends to turn both of the sites into renewable energy parks.  The plants will be converted into solar farms and battery units that can be used to store electricity generated by offshore wind turbines along the Atlantic Coast.  Granite Shore Power bought the two power plants in 2018 with the intention of transitioning the coal generation systems into less polluting operations.

The battery storage system at the Schiller Station site in Portsmouth will be named the Jacona II in honor of a self-propelled floating power barge that brought power to parts of Maine and New Hampshire between 1919 and 1930.

Coal use has dropped dramatically in the United States in recent years as natural gas and renewable sources like wind and solar have become less expensive.  As of last year, coal only produced about 17% of American electricity and its use continues to decline. 

Coal is the dirtiest fossil fuel.  In 2021, when it generated less than a quarter of the electricity produced in the US, it accounted for 59% of carbon emissions from electricity generation.

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The Last Coal-Fired Power Plants in New England Are to Close

Photo, posted October 14, 2015, courtesy of Eversource NH via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Skiing and climate change

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According to the National Oceanic and Atmospheric Administration, anthropogenic climate change resulting in higher average temperatures has caused a global decline in snowfall.  Less snow threatens to reinforce global warming, and to disrupt food, water, and livelihoods for billions of people.  

According to a new study recently published in the journal PLOS ONE, annual snow cover days in all major skiing regions are projected to decrease dramatically as a result of climate change.  In the study, the research team from the University of Bayreuth in Germany examined the impact of climate change on annual natural snow cover in seven major skiing regions.  Using the public climate database CHELSA, the researchers predicted annual snow cover days for each ski area for 2011-2040, 2041-2070, and 2071-2100 under low, high, and very high carbon emissions scenarios.

Under the high emissions scenario, 13% of ski areas are predicted to lose all natural snow cover by 2071-2100 relative to their historic baselines.  By 2071-2100, average annual snow cover days were predicted to decline by 78% in the Australian Alps, 51% in the Southern Alps, 50% in the Japanese Alps, 43% in the Andes, 42% in the European Alps, 37% in the Appalachians, and 23% in the the Rocky Mountains – all declines relative to their historic baselines.

The future losses of natural snow cover in ski areas around the world will be significant if global emissions continue unchecked.

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The future is likely less skiable, thanks to climate change

New maps show where snowfall is disappearing

Photo, posted April 14, 2006, courtesy of Kallu via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Little ice on the Great Lakes

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In an average year, the Great Lakes end up about 40% covered in ice.  But this is not an average year.  2023 was the warmest year on record and, in fact, the global temperature was more than 1.5 degrees above the pre-industrial average for the full year.  That hasn’t happened before.  As a result of the record-breaking warmth, as of mid-February, the average ice cover on the Great Lakes was only 5.9%.

Lake Erie and Lake Ontario tied their records for the lowest ice cover, which has been tracked since 1973.  Lake Huron, Lake Michigan, and Lake Superior are at historic lows.  Some parts of the Great Lakes have experienced the winter without any ice cover.

The warming air temperatures have led to rapid ice loss and warming summer temperatures.  According to experts, if the planet continues to warm, more than 200,000 lakes may no longer freeze every winter and 5,700 lakes may permanently lose ice cover by the end of the century.

Studying the Great Lakes is important because their ice melt can be a significant indicator of the progress of global warming.  Decreasing ice cover can affect hydropower generation, commercial shipping and fishing, and have environmental impacts such as the development of plankton blooms.

Since the 1970s, there has been a 5% decline in Great Lakes ice cover per decade.  Unfrozen lakes bring more rain than snow which has environmental, cultural, and societal impacts.  The Great Lakes hold 21% of the world’s freshwater supply and over 30 million people depend on them for drinking water.  They are also linked to over $3 trillion in gross domestic product.

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Great Lakes Winter Ice Cover Averaging Just 5.9%: NOAA

Photo, posted November 7, 2007, courtesy of Jim Sorbie via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Confusion about monarch butterflies

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For years, we have heard that the iconic monarch butterfly is in great peril.  Monarchs east of the Rocky Mountains undertake a 4-generation, 3,000-mile migration in late summer to their winter home in central Mexico.  Since the 1990s, the overwintering monarch colonies began a steep decline causing scientists to fear for the sustainability of the species.  Trying to help, ordinary citizens have been planting milkweed – the food for the caterpillars – and have been rearing eggs and caterpillars on their porches and releasing adult butterflies.

A number of recent studies have rocked the world of monarch science.  A growing group of scientists now believe that monarchs are not in fact imperiled and that the home rearing and commercial breeding of monarchs is actually a major threat to the butterfly.

According to a comprehensive 2022 study, there has been no sharp decline in Eastern monarch populations across their summer breeding range.  The long-term declines in winter colony sizes are real but do not appear to be affecting the collective breeding population of Eastern monarchs. 

An undisputed major threat to monarchs is a parasite known as OE, which weakens butterflies and also makes it unlikely for them to complete migrations.  It turns out that overcrowding of butterflies resulting from the efforts of backyard and commercial breeders is increasing the spread of the disease.  The butterflies are in need of social distancing.

Monarch scientists are split into two camps.  One group calls for the protection of the butterfly under the Endangered Species Act.  The other says that what monarchs most need is for us to leave them alone.  It is a confusing situation.

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Rethinking Monarchs: Does the Beloved Butterfly Need Our Help?

Photo, posted October 1, 2021, courtesy of Renee Grayson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Why are bees making less honey?

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Scientists have been sounding the alarm on the global struggle of pollinators for a long time.  According to the United Nations, nearly 35% of the invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since 75% of the world’s food crops depend on pollination to some extent, the decline of pollinators poses a major threat to global food security.

Honey bees are among the struggling pollinators.  Honey bee colonies in the United States have experienced annual population declines since 2006.  But in addition to there being fewer bees, the bees that remain are also making less honey.  In fact, honey yields in the United States have been declining since the 1990s. 

A new study by researchers from Penn State University has solved some of the mystery.  Using five decades of data across the United States, the research team analyzed the factors that could be affecting the number of flowers growing in different regions, which, in turn, affects the amount of honey produced by bees. 

In the study, which was recently published in the journal Environmental Research, the scientists found that climate conditions and soil productivity were two of the biggest factors in estimating honey yields.  States in both warm and cool regions produced higher honey yields when they had productive soils.  These two factors set a baseline production level of honey, while herbicide use, weather, and land use changes influenced how much honey was produced in a given year. 

The study’s findings  provide valuable insights that should help beekeepers, growers, and land managers better support honey bees.

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Why are bees making less honey? Study reveals clues in five decades of data

Photo, posted August 30, 2021, courtesy of Brandon O’Connor / NRCS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lower carbon emissions in the U.S.

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American greenhouse gas emissions in 2023 fell by 1.9%.  In total, U.S. emissions have now fallen by over 17% since 2005.  The largest factor in the decline has been the reduction in the burning of coal to produce electricity.  Coal-fired generation has fallen to its lowest level in half a century.

There was a huge drop in emissions at the start of the covid pandemic when large segments of the economy shut down.  But then there was a sharp rebound in emissions in the following two years when economic activity resumed.  But over the long term, American emissions have been trending downward as both cars and power plants have become cleaner and greener.

The decline in emissions is a good thing but hasn’t been nearly enough to meet the nation’s goals for trying to slow down global warming.  The U.S. has a goal of reducing emissions by 2030 to half of the 2005 level.  To achieve that goal, annual emissions would have to fall more than three times faster than they did last year for the rest of the decade.

The emissions data used for the current assessment included those from transportation, electricity generation, industry, and buildings.  It did not include pollution from agriculture, which accounts for about 10% of the nation’s greenhouse gases.

The 2022 Inflation Reduction Act provided record amounts of money for low-emissions technologies like solar panels, wind turbines, nuclear reactors, electric vehicles, and hydrogen fuels.  The full impact of these federal investments has yet to be seen, since many companies are still ramping up their efforts in clean energy.  How quickly emissions will fall as these efforts come to fruition remains to be seen.

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U.S. Carbon Emissions Fell in 2023 as Coal Use Tumbled to New Lows

Photo, posted May 17, 2020, courtesy of Frans Berkelaar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Elephants and protected areas

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Standing up to 13 feet tall and weighing up to 7 tons, African savanna elephants are the largest species of elephant and the biggest terrestrial animal on Earth.  According to the World Wildlife Fund, African savanna elephants can be found in 23 countries and live in a variety of habitats, including savannas, forests, and deserts.  The largest populations are in Southern and Eastern African countries.

According to assessments from the International Union for Conservation of Nature, the population of African savanna elephants has decreased by at least 60% over the last 50 years.  Poaching and habitat loss are the two main drivers of the population decline.  In 2021, the status of the African savanna elephant was changed from vulnerable to endangered on the IUCN’s Red List of Threatened Species. 

However, according to a new study recently published in the journal Science Advances, conservation measures have successfully stopped African savanna elephant population declines across southern Africa.  The international team of researchers found that the pattern varies regionally, with some elephant populations soaring while others are still facing large declines.

Overall, the study found that there are the same number of elephants now as there were 25 years ago. According to researchers, the key to long-term elephant population growth and sustainability isn’t where a protected area is, but rather how connected it is to other protected or neutral areas around it. 

This isn’t a new concept; in fact, many parks have been connected to one another.  But this study helps prove that the method is effective for elephant conservation.  

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Protected Areas for Elephants Work Best if They Are Connected

African elephant species now Endangered and Critically Endangered – IUCN Red List

African savanna elephant

Photo, posted October 20, 2018, courtesy of Ray via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)