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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

Examining The Decline Of Honey Bees | Earth Wise

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For many years, scientists have been sounding the alarm on the global struggle of pollinators.  Many 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.  Over the past 14 years, bee colonies have been disappearing at an alarming rate in what is known as the “colony collapse disorder.” 

In an effort to understand why, scientists have often focused their research on environmental stressors, such as parasites, pesticides, and disease.  But according to new research by entomologists from the University of Maryland, honey bee life spans are simply 50% shorter today than they were 50 years ago.  In the study, which was recently published in the journal Scientific Reports, the researchers found that honey bees kept in a controlled, laboratory environment lived half as long as honey bees did in the 1970s.  This is the first study to show that genetics – as opposed to environmental stressors – may be influencing the broader trends seen in the beekeeping industry.

When the researchers modeled the effect of their findings on a beekeeping operation, they found that the resulting loss rates were about 33%.  This is similar to the average overwinter and annual loss rates reported by beekeepers during the past 14 years.

The next step is for researchers to compare trends in honey bee life spans across the U.S. and in other countries to see if there are differences in bee longevity. 

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Honey Bee Lifespans are 50% Shorter Today Than They Were 50 Years Ago

Helping Agriculture’s Helpful Honey Bees

Photo, posted June 23, 2007, courtesy of Susan E. Ellis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Miracle Tree | Earth Wise

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The world needs to be fed without destroying the environment.   We need to grow more trees to store more carbon on earth and reduce the amount in the atmosphere.  But meanwhile, we decimate rainforests to produce palm oil and grow soybeans.

A startup company in California called Terviva thinks they have a solution.  It’s called pongamia, which is an ordinary looking tropical tree.  It produces beans packed with protein and oil, much like soybeans.  However, it has the potential to produce much more nutrition per acre than soybeans and it is hardy enough to grow on pretty much any kind of land without the use of pesticides, fertilizers, or irrigation.  In short, it is a miracle crop for a hot and hungry planet that is running out of fertile farmland and fresh water.

Pongamia is not a new or rare tree.  It is common in India but grows all over the world.  It is often planted as an ornamental here in the U.S.

The initial idea for making use of the hardy tree was to use its oil as a biofuel.  The seeds of pongamia are known to have a bitter taste and disagreeable odor, which is why the seeds or oil were never used for human or animal feed.  However, Terviva has developed a way to de-bitter pongamia oil.  Once this is done, it becomes a golden-colored substitute for olive oil. It also has enormous potential as a protein for plant-based milks and meats, since it contains all nine essential amino acids.

Terviva has raised more than $100 million to further develop pongamia and is now partnering with Danone, a $25 billion multinational food company, to develop pongamia as a climate-friendly, climate-resilient, non-GMO alternative to soy and palm oil.

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This super-tree could help feed the world and fight climate change

Photo, posted December 15, 2015, courtesy of Lauren Gutierrez via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Declining Flying Insects | Earth Wise

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In recent years, there has been increasing awareness of the global decline in insect abundance.  A recently published survey of the abundance of flying insects in the UK has revealed very troubling results.

The Kent Wildlife Trust and Buglife – two UK-based conservation groups – compared the number of dead insects on vehicles in 2004 and 2021.  In this Bugs Matter Citizen Science Survey, the data was collected by roughly 20,000 ordinary citizens using a smartphone app.

The results were that the number of flying insects in Britain dropped nearly 60% over that time period.  The insects declined most in England and Wales, with drops of 65% and 55%, respectively. 

It is possible that 2004 was a particularly good year for British insects and 2021 an especially bad one, but the findings of this study are consistent with other research around the world showing an alarming decline in insects.  A series of studies in 2019 found that the global mass of insects is shrinking by 2.5% a year and that insects are going extinct eight times faster than reptiles, birds, or mammals.

Insects face multiple overlapping threats including the destruction of wild habitats for farming, urbanization, pesticides, and light pollution.  On top of these things is climate change which is disrupting ecosystems in multiple ways.

Insects play a vital role in pollinating crops, consuming organic waste, killing pests, and as essential parts of multiple ecosystems.  Severe insect declines can potentially have dire global ecological and economic consequences.

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Flying Insects Have Declined by 60 Percent in the U.K., Survey Finds

Insect decline in the Anthropocene: Death by a thousand cuts

Photo, posted May 6, 2007, courtesy of Richard Giddins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Managing Pests With Cover Crops | Earth Wise

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The use of pesticides in global agriculture brings with it many problems including the killing of non-target, beneficial species as well as reversing pest-management gains from the use of conservation agriculture methods.

In a newly published study by researchers at Penn State University, the use of plant cover, such as cover crops, was shown to potentially be more effective at reducing pest density and crop damage than the application of insecticides without the downsides.  Cover crops reduce insect pest outbreaks by increasing pest predator abundance.

Cover crops are plantings that are primarily used to slow erosion, improve soil health, enhance water availability, smother weeds, and help control pests and diseases.  Typical cover crops include mustard, alfalfa, rye, clovers, buckwheat, and winter peas.  Most cover crops are fairly inexpensive to plant.

Plant cover can provide habitat for populations of natural enemies of pests.  Winter cover crops can harbor pest predator populations outside of the growing season of the cash crop.  When the cover crop is killed off to allow the growth of the cash crop, residues of the cover crop remain on the soil during the growing season, so they still enhance the habitat for pest predators.

Conservation agriculture includes methods like cover crops, no-till planting, and crop rotation.  The use of cover crops constitutes a form of preventive pest management that is an alternative to planting seeds treated with systemic insecticides to control early-season pests.  There is also the possibility for integrated pest managements, which is an approach in which insecticides are applied but only when pest numbers exceed economic thresholds despite the use of nonchemical tactics.

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Cover crops more effective than insecticides for managing pests, study suggests

Photo, posted August 8, 2011, courtesy of USDA NRCS Montana via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Plight Of Monarch Butterflies | Earth Wise

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The monarch butterfly is one of the world’s best-known butterflies and has become the symbol for a whole class of imperiled pollinators.  Populations of the iconic orange-and-black insects have declined dramatically in recent decades. 

According to the U.S. Fish and Wildlife Service, the eastern monarch population has dropped 88% between 1996 and 2020.  Habitat loss, pesticide use, and global climate change are some of the factors driving monarch butterfly population declines. 

According to a new study led by scientists at Emory University, monarch butterflies are also increasingly plagued by a debilitating parasite.  The study, which was recently published in The Journal of Animal Ecology, reviewed 50 years of data on the infection rate of wild monarch butterflies by the protozoan Ophryocystis elektrosirrha (or O.E.).  The research team found that the O.E. infection rate had increased from less than 1% of the eastern monarch population in 1968 to as much as 10% today.

The O.E. parasite invades the gut of monarch caterpillars.  If the adult butterfly leaves the pupal stage with a severe parasitic infection, it begins oozing fluids from its body and dies. If the infection is lighter and the butterfly survives, it will not fly as well or live as long as uninfected butterflies.  

The study found that one of the contributors to the rise in parasitism is the increased density of monarchs in places where they lay their eggs.  The increased density may be due to several factors, including the loss of habitat, the widespread planting of non-native milkweed, and by people raising large numbers of monarchs in confined spaces. 

If the infection rate continues to increase, monarch butterfly populations will likely continue to plummet. 

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Monarch butterflies increasingly plagued by parasites

Plight of the Monarch

Saving The Monarch Butterfly

Photo, posted September 18, 2008, courtesy of Roy Niswanger via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Great Christmas Tree Debate | Earth Wise

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Along with cookies and carols, the Christmas tree is a quintessential part of the holiday season for many people.  According to the American Christmas Tree Association, approximately 75% of Christmas trees in American homes this year will be artificial.  But are artificial trees really the better option for the planet?

The short answer is no.  But it’s more complicated than that.  Ultimately, the answer depends on a variety of factors.

If you decide to go with an artificial tree, you need to use it for a very long time. Studies suggest artificial trees would need to be reused anywhere from 8 to 20 years in order to be considered the more environmentally-friendly option. You should seek out trees manufactured from polyethylene plastic as it’s not as toxic as polyvinyl chloride plastic.  And since the majority of artificial trees are imported from China, look for a “Made in USA” label to reduce the carbon footprint.

If you decide to go for a live tree, shop local. This keeps the carbon footprint low and helps support the local economy in the process.  While some tree farms do spray, researchers say the use of pesticides in tree production is relatively low.  Live trees can also be composted or recycled afterwards.

It’s important to note that live Christmas trees can also be purchased with roots and planted after the holidays.  Some companies even allow you to rent live trees.  Each rented tree can be re-rented for up to seven years, after which it’ll be too large for in-home use and gets planted in its forever home. 

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Photo, posted December 17, 2017, courtesy of Alan Sandercock via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Harnessing The Smell Of Fear | Earth Wise

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Plant-eating insects present a major problem for farmers and home gardeners.  Aphids, for example, are a highly destructive pest to many crops.  Their large numbers and ability to transmit plant pathogens make them a persistent problem for growers.

Pesticides are chemical substances that are commonly used to prevent, destroy, repel or mitigate pests.  They include insecticides for insects, rodenticides for rodents, herbicides for weeds, and fungicides for microorganisms.  According to the U.S. Geological Survey, approximately one billion pounds of these chemicals are used in the United States every year.     

But pesticides can also contaminate soil, water, and other vegetation, as well as kill many non-target species.  Exposure to these chemicals is dangerous for human health. 

According to a new study, researchers from Pennsylvania State University have developed a way to bottle the “smell of fear” produced by predators in order to repel and disrupt pests naturally without the need for these harsh substances.  The researchers recently presented their findings at the American Chemical Society meeting.  

Aphids happen to be a favorite food of ladybugs. Aphids and other herbivorous insects will steer clear of fields and gardens if they smell predators nearby.  The researchers identified and extracted the volatile odor profile from ladybugs.  The researchers used the compounds to create a special odor blend that can be used in an essential oil diffuser to spread the scent across a garden or field. 

The research team plans to conduct field tests to see if the effects outside are similar to what was observed in the lab.  A natural and effective pest repellent would be a big win for people and the planet.  

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Protecting gardens and crops from insects using the ‘smell of fear’

Protecting gardens and crops from insects using the ‘smell of fear’ (YouTube)

Photo, posted May 10, 2011, courtesy of DM via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Promoting Biodiversity In Agriculture | Earth Wise

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The organic foods industry is one of the fastest growing agricultural segments in the United States.  According to the Organic Trade Association, U.S. organic sales reached $61.9 billion in 2020, a jump of more than 12% over the previous year. 

Organic food has many benefits.  Organic food is free of antibiotics, growth hormones, and GMOs, and is grown using fewer pesticides.  Organic farming tends to be better for the environment by reducing pollution, conserving water, reducing soil erosion, increasing soil fertility, and using less energy.   And it’s also better for the health of nearby wildlife as well as the people who live close to farms. 

But when it comes to promoting biodiversity in agriculture, is organic farming the only alternative to conventional agriculture? It turns out it’s not – at least according to a new study recently published in the journal Trends in Ecology and Evolution. 

According to an international research team led by the University of Göttingen in Germany, a landscape mosaic of natural habitats and small-scale and diverse cultivated areas is the key to promoting biodiversity on a large scale in both conventional and organic agriculture.

According to the research team, areas cultivated to organic standards have one third more species, but don’t reach the yield level of conventional farming.  This means that more land would need to be cultivated organically in order to produce the same amount of food.  But as larger areas are cultivated, the advantages for biodiversity would disappear.    

Landscapes with small fields, long edges, high crop diversity, and at least 20% near-natural habitats can promote biodiversity significantly more than just organic certification.   

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U.S. Organic Industry Survey 2021

Promoting biodiversity-friendly landscapes – beyond organic farming

Photo, posted August 29, 2019, courtesy of Lance Cheung/USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Bees From Pesticides | Earth Wise

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Studies have shown that the wax and pollen in 98% of beehives in the U.S. are contaminated with an average of six pesticides.  These substances lower bees’ immunity to devastating varroa mites and other pathogens.  By some estimates, pesticides cause beekeepers to lose about a third of their hives every year on average.

Researchers at Cornell University have developed a new technology that effectively protects bees from insecticides.  The insecticide antidote delivery method is now the basis of a new company called Beemunity.

The Cornell researchers developed a uniform pollen-sized microparticle filled with enzymes that detoxify organophosphate insecticides before they are absorbed and can harm bees.  Organophosphate insecticides account for about a third of the insecticides on the market.  The microparticles have a protective casing that allows the enzymes to move past the bees’ crop (basically the stomach), which is acidic and would otherwise break them down.  The safeguarded enzymes then enter the midgut, where digestion occurs and where toxins and nutrients are absorbed.  There the enzymes act to break down and detoxify the organophosphate insecticides.

In experimental tests, bees that were fed the enzyme-filled microparticles had a 100% survival rate after exposure to the insecticide malathion.  Unprotected control bees died within days.

The Cornell work appears to represent a low-cost, scalable solution to the insecticide toxicity issue and may help to protect essential pollinators.

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Pollen-sized technology protects bees from deadly insecticides

Photo, posted January 30, 2020, courtesy of George Tan via Flick.

Earth Wise is a production of WAMC Northeast Public Radio.

Residential Gardens And Pollinators | Earth Wise

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A new study led by the University of Bristol in the UK measured for the first time how much nectar is produced in urban areas to gauge the role of residential gardens in providing nutrients for pollinators.  They discovered that home gardens accounted for the vast majority of the crucial nutrients for pollinators; in fact, some 85% on average.

The study found that gardens generated a daily average of about a teaspoon of the unique sugar-rich liquid found in flowers which pollinators drink for energy.  A teaspoon sounds like very little, but it is enough to feed thousands of bees.

The research examined nectar production in four major UK towns and cities and measured nectar production in nearly 200 species of plants.  The results were that the nectar supply in urban landscapes is more diverse than in farmland and nature reserves.   In addition, gardens are critical because they produce the most nectar per unit area of land and actually cover the largest area of land in the cities studied.  In those cities, nearly a third of the land comprised domestic gardens, which is six times the area of parks and 40 times the area of small green allotments.

The upshot of the research is that home gardeners have a huge role to play in pollinator conservation.  Without domestic gardens, there would be far less food for pollinators that include bees, wasps, butterflies, moths, flies, and beetles.  Thus, it is important for home gardeners to keep planting nectar-rich flowers, mow lawns less often to let dandelions, clovers, and daisies flourish, avoid harmful pesticides, and avoid covering gardens in paving, decking, or artificial turf.

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Pioneering research reveals gardens are secret powerhouse for pollinators

Photo, posted June 23, 2018, courtesy of Wolfferl via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe’s Green Deal: Bad For The Planet? | Earth Wise

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In 2019, the European Union announced the “Green Deal,” a comprehensive program aimed at making Europe the first climate-neutral continent, implementing environmentally friendly transport, increasing recycling, and expanding renewable energy.

The Green Deal involves significant changes to European agriculture.  Over the next ten years, under the ambitious environmental program, at least a quarter of all agricultural areas will be farmed organically, the use of fertilizers and pesticides greatly reduced, 3 billion trees planted, 15,000 miles of rivers restored, and the population declines of pollinators reversed.

However, in a recent article published in Nature, scientists at the Karlsruhe Institute of Technology show that this Green Deal might actually be a bad deal for the planet.

The problem is that the EU is likely to basically be outsourcing environmental damage by its high imports of agricultural products.

According to the Karlsruhe study, the EU annually imports millions of tons of agricultural products, as much as 20% of its produce and much of its meat and dairy products.  Quite often, these imports come from countries whose environmental laws are far less stringent than those in Europe.

The EU cannot impose environmental standards on other countries, but it can demand that goods entering the European market meet EU requirements.  The study points out that Europe’s carbon footprint has to be evaluated on a global basis.  If the EU is truly to become a climate-neutral continent, it must include foreign trade goals and requirements in its environmental programs.  Otherwise, Europe will simply be outsourcing its environmental problems and will continue to cause damage to the planet.

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Green Deal: Good for a Climate-neutral Europe – Bad for the Planet

Photo, posted July 17, 2009, courtesy of Edmund Garman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Essential Oils And Organic Crops | Earth Wise

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Essential oils are concentrated liquids extracted from plants.  They are called “essential” in the sense that they contain the essence of the fragrance that is characteristic of the plant.  Essential does not mean indispensable or usable by the human body.  But despite that fact, essential oils have been used in folk medicine throughout history. 

In recent times, essential oils have frequently been used in aromatherapy.  Generally speaking, medicinal uses of essential oils are controversial, and, in some cases, they have even been demonstrated to be dangerous.

Research has shown that essential oils have potential as natural pesticides.  Recently, the USDA has funded research into the use of essential oils to battle pests and diseases of organic crops.

U.S. organic food sales topped $50 billion in 2018 and fruits, vegetables, and other specialty crops combined make up more than a third of organic sales.  In order to meet consumer demand, farmers need ways to battle pests and diseases that often accompany organic crop growth.

A four-year project at the University of Hawaii at Manoa is entitled “Plant Safety, Horticultural Benefits, and Disease Efficacy of Essential Oils for Use in Organically Grown Fruit Crops:  From the Farm to the Consumer.”   The researchers will work with certified organic producers in Hawaii, Florida, South Carolina, Georgia, and California to evaluate the effectiveness of plant essential oils on major fruit pathogens such as avocado scab, anthracnose fungal disease, and powdery mildew on targeted tropical and temperate fruit crops such as avocado, mango, blueberry, and peach.

The goal is increase orchard productivity of the expanding organic fruit industry.

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Essential oils could keep pests, disease from organic crops

Photo, posted January 6, 2015, courtesy of Abi Porter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bees Threatening Bees | Earth Wise

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Domesticated honeybees are an essential part of our agricultural system, being responsible for one in every three bites of food Americans consume and contributing $15 billion a year to the value of the nation’s crop production.  Millions of bee colonies are trucked across the country every year to pollinate cranberries, melons, broccoli, blueberries, and cherries, and also to produce honey.

After the growing seasons, honeybees are trucked to various locations to rest and rebuild their population and to replenish bees lost to disease and pesticides.  Some of these locations are in national forests.  Thousands of hives belonging to 112 apiaries are currently permitted in national forests by the Department of Agriculture.  This presents a problem because these hives are being permitted on public lands with virtually no environmental review and with little consideration of the impact these colonies can have on local wild bee populations.

The 4,000 wild bee species in the U.S. consume up to 95% of local available pollen.  Nearly 40 federally listed threatened or endangered species of bees, butterflies, and flower flies depend on national forest land for their survival.  And now the pollinators in these places, which were once refuges for these species and others, increasingly face competition from millions of domesticated honeybees.

Honeybees are super-foraging machines and are literally taking the pollen out of the mouths of other bees and pollinators.  Honeybees themselves have been facing numerous problems from habitat loss, pesticides, and other stress factors.  So, what is happening is essentially a pollinator habitat crunch that carries long-term implications for the U.S. food supply.  We need to find some answers and the sooner the better.

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Will Putting Honey Bees on Public Lands Threaten Native Bees?

Photo, posted August 9, 2015, courtesy of Tak H. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Native Bees In A Honeybee World | Earth Wise

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

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

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

Native bees are in big trouble.

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Backyard Battle: Helping Native Bees Thrive in a Honeybee World

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

Earth Wise is a production of WAMC Northeast Public Radio.

More Trouble For Monarchs | Earth Wise

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Monarch butterflies have been in trouble for quite a while and now it seems like their prospects are worse than ever.  Multiple surveys of butterfly populations are reporting plummeting numbers.

Western monarch butterflies spend their winters on the central California coast.  Months later, they breed in California’s Central Valley and as far north and east as Idaho.  But in recent years, it has become harder and harder to find them in their breeding sites.

The Western monarch population was in the millions in the 1980s.  In 2017, an annual survey found 200,000 butterflies.  In 2018 and 2019, only about 30,000 butterflies were tallied.  The loss of Western butterflies in general has come about from a variety of factors, including development, climate change, farming practices and the widespread use of pesticides by farmers and on home and business lawns.

Scientists use the area of land that migrating Monarchs occupy in Mexico to gauge populations.  This year, they covered about 7 acres, down from 15 acres in 2019.

Meanwhile, there are also far fewer Eastern monarch butterflies on the opposite side of the country.  According to a new population survey, the Eastern monarch has passed the extinction threshold.  Its population in 2020 dropped 53% from its already low 2019 numbers.  Scientists were expecting lower numbers this year, but they were staggered by their findings.

Butterfly populations are quite variable, so it is possible that the drastic declines this year are not necessarily irreversible, but the news is not good.   Researchers and environmental advocates continue to point out that mitigating the climate crisis, reducing pesticide use and planting pollinator gardens could help the butterflies to recover.

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Monarch Butterfly Populations Are Plummeting

Photo, posted September 7, 2017, courtesy of C. Watts via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tough Times For Fireflies | Earth Wise

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

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

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

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

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

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

We can’t afford for fireflies to go dark. 

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A Global Perspective on Firefly Extinction Threats

Fireflies Have a Mating Problem: The Lights Are Always On

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

Earth Wise is a production of WAMC Northeast Public Radio.

Pesticides In The Great Barrier Reef

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Australia’s Great Barrier Reef is one of the greatest natural wonders in the world and it has been under siege by warming waters and ocean acidification.  Widespread coral bleaching has damaged or destroyed large portions of the 1,400-mile long coral reef system.  But the effects of climate change are not the only threat to the reef.  Pesticides found in waterways that flow into the Great Barrier Reef are another serious problem.

According to a new study by the University of Queensland, the combined toxicity of 22 of the most common pesticides that flow into the Reef are not meeting pollution reduction targets.

Different pesticides affect different organisms.  Herbicides affect organisms that photosynthesize such as seagrass, corals, mangroves, and algae.  Insecticides affect insect larvae in freshwater, and crustaceans such as crabs, prawns, and lobsters.  Previous assessments have only examined individual pesticides and only for limited times.  The new study has utilized a methodology that estimates the combined toxicity of multiple pesticides found in the waterways that discharge into the Reef and does it for the entire wet season.

The research revealed that the pesticide reduction target set in the Australian Government’s Reef 2050 Water Quality Improvement Plan is not being met.  Only one natural resource management region – the Cape York region – was found to be meeting its target.

By having estimates of the risk posed by pesticides in the various regions and individual waterways, governments, farmers, and conservationists can see which areas pose the greatest risk and where to maximize efforts.  Stakeholders have to come together to reduce pesticide concentrations through better management practices and by using less toxic pesticides.

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High pesticide concentrations continue to enter Great Barrier Reef

Photo, posted July 29, 2010, courtesy of Kyle Taylor via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Birds Are Disappearing

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A new analysis, published in the journal Science, reports that the number of birds in the United States and Canada has fallen by 29% since 1970.  There are 2.9 billion fewer birds in the two countries now than there were 50 years ago.

The analysis is the most comprehensive attempt to date to look at the status of avian populations.  The results were a shock to researchers and conservation organizations.

It is well-known that some bird species have become vulnerable to extinction, but the new study, which surveyed more than 500 species, uncovered steep losses even among such traditionally abundant birds as robins and sparrows.

There appear to be multiple causes for the steep declines.  The largest ones are likely habitat loss and the wider use of pesticides.  Rachel Carson’s 1962 book Silent Spring warned of the dangers of pesticides and took its title from a world that has lost its birds.

The survey includes 76% of all bird species in the US and Canada, but actually represents almost the entire population of birds.  Grassland species have suffered the biggest declines by far, as a result of modern agriculture and development.  Pesticides, such as neonicotinoids, make it harder for birds to put on weight needed for migration, delaying their travel.

There are a few bright spots:  bald eagles are thriving, and falcon and waterfowl populations are on the upswing.  These are species that have been the subject of conservation measures in recent decades.

Stopping the bird decline will require a great deal of effort to defend habitats, restrict chemicals, and redesign buildings.  Without that effort, birds will continue to disappear.

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Birds Are Vanishing From North America

Photo, posted April 1, 2012, courtesy of Barry Skeates via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Falling Bee Populations

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For many years, scientists have been sounding the alarm on the global struggle of pollinators.  A reported 40% of invertebrate pollinator species, including bees and butterflies, are facing extinction. And since as much as three-quarters of the world’s food crops depend on pollination, the decline of these pollinators poses a major threat to global food security.

Pollinators aid in the production of all sorts of crops, including coffee, cacao, cotton, apples, and almonds – to name a few.  The global value of crops requiring pollination ranges from $235-$577 billion annually.

Honey bees are among the struggling pollinators.  Over the past 15 years, bee colonies have been disappearing at an alarming rate in what is known as the “colony collapse disorder.”  Some regions have seen losses of up to 90%. 

In the United States, managed honey bee populations declined by nearly 40% over this past winter, the largest such winter decline since surveying began in 2006.

In recent months, mass honey bee declines have also been reported in Russia, according to the BBC.  Russia, which produces a whopping 110,000 tons of honey annually, expects that figure to drop by as much as 20%.  The widespread bee decline is likely to not only push up honey prices, but the prices of other popular foods as well.  Many staple food crops in Russia, including sunflowers, buckwheat, and fruit trees, rely on bees for pollination.

Experts have blamed the bee decline crisis on a combination of factors, including pesticides (most notably neonicotinoids), varroa mites, and climate change.   

Bees play a vital role in food production, and their continued decline will have devastating consequences. 

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Russia alarmed by large fall in bee populations

Photo, posted July 28, 2019, courtesy of Ivan Radic 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...)