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Protected Areas Are Not Protecting Insects | Earth Wise

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

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

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

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

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

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

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

Earth Wise is a production of WAMC Northeast Public Radio

Insects On The Menu | Earth Wise

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

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

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

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

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

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

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Insects on the menu as EU approves two for human consumption

World Hunger Surged in 2020, U.N. Says

A global food crisis

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

Earth Wise is a production of WAMC Northeast Public Radio

Rainforest Promises | Earth Wise

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The recent UN climate summit in Sharm el Sheikh, Egypt brought with it lots of pledges for action.   Among them was a promise from the three countries that are home to more than half of the world’s tropical rainforests to try to do something to protect them.

The ministers of Brazil, Indonesia, and the Democratic Republic of Congo signed an agreement pledging cooperation on sustainable management and conservation, restoration of critical ecosystems, and creation of economies that would ensure the health of both their people and their forests.

The plan has no financial backing of its own.  The countries are pledging to work together to establish a funding mechanism that could help to preserve the tropical forests that both help regulate the Earth’s climate and sustain a wide range of animals, plants, birds, and insects.

That such an agreement has come about at all is a result of the election of Luiz Lula da Silva as Brazilian president, replacing Jair Bolsonaro, who was famously an opponent of any and all environmental conservation or protections.  President Lula addressed the attendees of the climate summit promising that “Brazil is back.”   He described his country as having been in a cocoon for the past four years under his predecessor.  He declared that going forward, Brazil will be a force to combat climate change.  Given the importance of the Amazon rainforest, that is critical for the success of the world’s efforts.

Like all other issues on the table at the climate summit, the real challenge is not to come up with meaningful pledges on climate action, it is to be able to follow through on those pledges.  If past summits are any indication, that is not an easy task.

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Brazil, Indonesia and Congo Sign Rainforest Protection Pact

Photo, posted September 15, 2013, courtesy of Moises Silva Lima via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Glacial Loss In The Swiss Alps | Earth Wise

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In 2022, glaciers in the Swiss Alps melted more than in any year on record.   This is the latest piece of bad news for the country’s glaciers, which have lost more than half of their volume of ice since the 1930s.

The melting season for Switzerland’s snow and ice typically starts in May and ends in early October.  This year’s melting season caused glaciers in the Diablerets mountain group to thin by an average of 13 feet, which is 3 times the amount of thinning observed over the past decade.   The Tsanfleuron pass between two of the glaciers is now exposed as bare rock for the first time in several thousand years. Across Switzerland, glaciers lost about 6% of their remaining volume just this year.  The previous worst year for glaciers was 2003, when losses were nearly 4%. 

There was significant melting this year in part because of the small amount of snowfall over the winter.  That snow melted quickly, being sped up by the warming effect of dust from the Sahara Desert falling on the snow.  By early summer, there was no longer a protective blanket of snow on the glaciers, exposing them to summer heat.

The loss of glaciers is far more serious than the disappearance of aesthetically pleasing landscape features.   Glaciers act as reservoirs of water that persist through the summer months.  Melt from glaciers provides water to ecosystems and creates habitats for plants and animals.  Cold runoff from glaciers affects downstream water temperatures which have a major impact on insects, fish, and other creatures.  Globally, melting glaciers contribute more than 20% of the observed ongoing sea-level rise.

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Rocky Road for Swiss Glaciers

Photo, posted June 22, 2015, courtesy of Dennis Jarvis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mosquito Magnets | Earth Wise

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We’ve all probably had the experience of being in the great outdoors with other people and having some of them being nearly devoured by mosquitoes while others didn’t get bitten at all.  It seemed like some people are mosquito magnets while others just aren’t the insects’ cup of tea, so to speak.

There have been various theories proposed over the years including such things as it being a question of blood type, or it having to do with how close one’s blood vessels are to their skin surface.

A new study by the Howard Hughes Medical Institute and the Rockefeller University has uncovered what appears to be the real explanation.  According to the paper published in the journal Cell, certain body odors are the deciding factor.  Every person has a unique scent profile associated with different chemicals present on their skin.  The researchers found that people whose skin produces high levels of carboxylic acids are the most attractive to mosquitos.

The researchers collected scent samples from participants by having them wear silk stockings on their arms for six hours.  The nylons were then cut into pieces and the pieces exposed to mosquitos.  After several months of head-to-head battles between various nylon samples, the study clearly demonstrated that the samples from subjects with higher levels of carboxylic acids in the skin were far more attractive to mosquitos.

Humans produce the substance at much higher levels than other animals.  There is little one can do about their own levels.  Changing one’s diet or what soap they use doesn’t seem to make a difference. 

Perhaps researchers can come up with some method of breaking down carboxylic acids in the skin in the future.  Until such time, there are really people who are mosquito magnets.

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Some People Really Are Mosquito Magnets, and They’re Stuck That Way

Photo, posted September 4, 2014, courtesy of James Gathany / Centers for Disease Control via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Insects In A Changing Climate | Earth Wise

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

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

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

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

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Tropical insects are extremely sensitive to changing climates

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

Earth Wise is a production of WAMC Northeast Public Radio

Why Do Woodpeckers Peck? | Earth Wise

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Most of us have heard the sound of a woodpecker drumming on a nearby tree, or unfortunately, on the walls of our house where it can be very destructive.  We were often told that the birds were hunting for insects inside the wood, or perhaps trying to open up a nest. But a new study at Brown University has found evidence that woodpeckers are just additional musicians in the bird orchestra who happen to be percussionists.

The researchers studied the forebrains of birds and found characteristic gene expression specializations in songbirds.  Songbirds sing to communicate for various reasons – such as staking out territory or seeking mates.  The study looked at birds that are not known to sing, such as the emu, penguin, flamingo, and woodpeckers.  It turns out that among these, only woodpeckers had forebrains that anatomically resembled those of songbirds.  The study is the first time a neural basis has been identified for the communication activities of animals other than primates.

There are over 200 species of woodpeckers around the world and each species has its own characteristic drumming speed and rhythms.  Woodpecker drumming may well have evolved through a form of vocal learning, which is the way songbirds learn to make their own melodious sounds.  And like the calls of songbirds, these drumming patterns change depending on what the birds want to communicate and to whom.

So, the little downy woodpecker that is poking holes in your walls is probably not hunting for insects.  It is more likely to be telling another woodpecker to get out of its territory.

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Why do woodpeckers peck? New discovery about bird brains sheds light on intriguing question

Photo, posted June 15, 2021, courtesy of Tony Oldroyd via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

visit site by the doctor who prescribed the drug. Prescription. If the drug is sold in Russia without a prescription, it is necessary to make sure that the drug will also be sold abroad without it. You can find out in advance and, for example, write a letter to a specific pharmacy abroad, or you can be reinsured and ask to make a prescription form for the drug from your doctor.

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.

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.

Tourism And Invasive Species | Earth Wise

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Tourism has experienced exponential growth during the past 70 years.  In 1950, there were 25 million international tourist arrivals.  By 1990, it had ballooned to 435 million.  Between 1990 and 2018, the numbers more than tripled reaching more than 1.4 billion.  And by 2030, the number of international tourist arrivals is expected to reach 1.8 billion.

Tourism is vital to the success of many economies around the world.  Tourism can boost revenue, provide jobs, develop infrastructure, protect wildlife, and help preserve heritage sites and cultures.  But there can also be many downsides to tourism, one of which is that it can contribute to the introduction and spread of invasive species.  Non-native organisms can cause all sorts of social, environmental, and economic damage.   

Tourists help spread invasive organisms far and wide.  These organisms hitch rides in their luggage and on their shoes and clothing.  A 2011 study in New Zealand found that for every gram of soil on the shoes of in-bound international passengers, there were 2.5 plant seeds, 41 roundworms, 0.004 insects and mites, and many microorganisms. 

A new study by researchers from the University of Melbourne in Australia and AgResearch New Zealand examined to what degree tourism plays a role in the spread of invasive species.  According to the study, which was recently published in the journal NeoBiota, the research team found that the number of nights spent in hotels significantly correlated to the incursion of invasive species during that period.

Creating effective mechanisms to prevent the introduction of invasive species in the first place is the best way to prevent this problem. 

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Unwelcome guests: International tourism and travel can be a pathway for introducing invasive species

Number of tourist arrivals

Photo, posted March 27, 2005, courtesy of John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tree Diversity | Earth Wise

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Scientists have estimated that there are more than 8 million species of plants and animals in existence.  Amazingly, only about 1.2 million of them have been identified and described so far and most of those are actually insects.  Millions of other organisms have yet to be discovered.

One would imagine that most of these unknown species are tiny things that are hard to spot or encounter.  But our ignorance of species even applies to trees, which are pretty easy to spot if you encounter them.

A new study involving more than 100 scientists across the globe has produced an estimate of the number of tree species on the Earth.  The new global estimate is that there are 73,000 tree species, which is about 14% more than previously thought.  Based on a combination of data from two global datasets, the study yielded a total of 64,100 documented tree species worldwide.  The researchers then used novel statistical methods to estimate the total number of unique tree species at biome, continental, and global scales, which includes species yet to be discovered and described by scientists.  Therefore, the estimate predicts that there are likely to be over 9,000 tree species still to be found.

Roughly 40% of the undiscovered tree species are likely to be in South America, which is the continent with the highest number of rare tree species and the highest number of continentally endemic tree species – meaning those found only on that continent.  Hot spots of undiscovered tree species are likely the tropical and subtropical moist forests of the Amazon basin and the Andes-Amazon interface.

Extensive knowledge of tree richness and diversity is key to preserving the stability and functioning of ecosystems.

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Number of Earth’s tree species estimated to be 14% higher than currently known, with some 9,200 species yet to be discovered

Photo, posted November 5, 2017, courtesy of Deensel via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Perennials To Attract Pollinators | Earth Wise

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There has been a decline in the abundance of insect and other animal pollinators in many ecosystems worldwide that began being observed at the end of the 20th century.  Pollinators and their health have become growing concerns for the public and many states have enacted legislation related to pollinator decline.

In many places, the pollinator decline has largely been driven by a loss of flowering plants in the landscape, the primary source of food for the pollinators.  A new study by Penn State researchers looked at the attractiveness to pollinators of various species of perennial flowering plants that people can plant in their gardens and other landscapes.

It turns out that there is considerable variation in how attractive different flowering plants are to pollinators.  Greenspaces such as parks and gardens have the potential to support very rich pollinator communities, even including rare or vulnerable species.

People generally select ornamental plants because of their appearance and growth habit, not because of their pollinator attraction.

The Penn State study looked at a variety of perennials and identified the most attractive plant cultivars, which can attract 4 times the number of pollinator species than the least attractive plants studied.

The most appealing plant is the ‘Blue Fortune’ giant hyssop.  Other highly attractive plants are the anise hyssop, the ‘Black Adder’ Agastache, the Cat’s Meow and Walker’s Low Nepetas, and the Triloba and Herbstonne Rudbeckias.

Many of these plants produce large floral displays and the researchers suggest that they should be prioritized when planting a pollinator garden amongst other species with comparably small floral displays and lower attractiveness to pollinators.

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Popular perennial flowering plants can attract diverse mix of pollinators

Photo, posted September 7, 2019, courtesy of KM via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Benefits Of No-Till Farming | Earth Wise

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No-till farming is not new.  In fact, it was used as far back as 10,000 years ago.  But during the 18th and 19th centuries, tilling became popular because it allowed farmers to plant seeds more efficiently.

Tilling (or ploughing) is the process of preparing the soil for the cultivation of seeds by overturning the soil.  The practice works animal manure, weeds, and other surface residues deep into the soil.  While this all sounds like a good thing, it’s not. 

Tilling removes plant matter and loosens the soil, leaving the soil bare and vulnerable to erosion.  Tilling also displaces the millions of microbes and insects that form healthy soil biology.  The long-term use of tilling can turn healthy soils into lifeless growing mediums dependent on chemical inputs.  

But no-till farming also tends to rely on chemical inputs like glyphosate for weed control.  According to a new study recently published in Agronomy Journal, researchers at Penn State have found that farmers using no-till farming can reduce herbicide use and still maintain crop yields by implementing integrated weed-management methods.   

The research team conducted a nine-year experiment using herbicide-reduction practices in a crop rotation, which included soybean, corn, alfalfa, and canola.  Some of the practices used to reduce herbicide inputs included seeding small-grain companion crops with perennials, and plowing once in six years to terminate the perennial forage rather than killing it with an herbicide. 

While there was more weed biomass in the reduced herbicide treatment, the researchers found that the added weed pressure did not substantially affect crop yields. 

It is possible to make agriculture more environmentally-friendly and sustainable without sacrificing productivity.

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No-till production farmers can cut herbicide use, control weeds, protect profits

Photo, posted February 11, 2019, courtesy of the United Soybean Board 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.

Tropical Species Moving North | Earth Wise

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Climate change is leading to warmer winter weather throughout the southern U.S., providing opportunities for many tropical plants and animals to move north.  A new study by scientists at UC Berkeley looked at the changing distribution of tropical species driven by the warming climate.

Some species are appreciated in their new locations, such as sea turtles and the Florida manatee, which are gradually moving northward along the Atlantic Coast.  Others, like the invasive Burmese python are not so welcome.  That goes double for many insects, such as the mosquitoes that carry diseases like the West Nile virus, Zika, dengue, and yellow fever, as well as beetles that destroy native trees.

The transition zone, northward of which experiences freezes every winter, has always been a barrier to species native to more temperate places.  For most organisms in such places, if they freeze, they die.  Cold snaps like the recent one in Texas usually don’t happen for decades and are now likely to be less and less frequent.  In the meantime, tropical species can get more and more of a foothold and maybe even develop populations that can tolerate more cold extremes in the future.

The warming climate is leading many plant species to expand their ranges, in some cases pushing out native species.  The general story is that the species that do really well are the more generalist species whose host plants or food sources are quite varied or widely distributed and can tolerate a wide range of conditions.  By definition, they tend to be the pest species.

We need to prepare for widespread shifts in the distribution of biodiversity as climate, including winter climate, changes.

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Tropical species are moving northward as winters warm

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

Earth Wise is a production of WAMC Northeast Public Radio.

Living On Trash | Earth Wise

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Litter is persistent and widespread in rivers worldwide.  The world’s major rivers and estuaries are hotspots for plastic waste.  Trash and microparticles wash down tributaries and build up before rivers enter oceans.

New research published in the journal Freshwater Biology has found that as this waste accumulates, aquatic river species like insects and snails are increasingly choosing to settle on plastic rather than on natural features like rocks and fallen branches.

Researchers from the University of Nottingham in the UK collected plastic waste from three rivers in eastern Britain along with rocks from the same rivers.  Their analysis of all the macroinvertebrates on the items’ surfaces found that the surfaces of plastic waste items had nearly four times the diversity of the small animals as did the rocks.  In addition, the more complex the plastic’s surface was, the higher the diversity.

The growing abundance of plastic waste coincides with a decline in natural habitat features in urban rivers.  This is a result of increasing amounts of sedimentation from development that blankets riverbeds in silt and sand, restricting the supply and movement of rocks, fallen tree branches, and aquatic plants.

Clearly litter can serve as a place for various species to colonize, but trash is not a good environment for them.  Trash can release toxic chemicals and entangle animals.  Microplastics pose risks for the animals if ingested.

Estimates are that between 1.15 and 2.41 million tons of plastic waste enter the ocean every year from rivers around the world.  Natural habitats have become rare in urban rivers.  River ecosystems built around piles of trash are not a good thing.

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As Plastic Pollution in Rivers Gets Worse, Species Are Increasingly Living on Litter

Photo, posted August 17, 2010, courtesy of Renee_McGurk via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Not Enough Buzz For Bees | Earth Wise

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The dramatic worldwide decline in bees and other pollinating insects represents a serious threat to the global food supply, but it isn’t really getting much attention in the mainstream news.  Close to 75% of the world’s crops for human consumption depend, at least in part, on pollinators for sustained production, yield, and quality.

A new study by researchers at the University of Illinois Urbana-Champaign looked at nearly 25 million news items from six prominent sources, including The New York Times, The Washington Post, the Associated Press, as well as three overseas English-language news services.  The study found “vanishingly low levels of attention to pollinator population topics”, even compared with what many people consider to be the limited coverage of climate change.

The study made use of the Global News Index, which is a unique database of millions of news items from thousands of global sources published over decades.  It may be the largest academic study of the evolving nature of news coverage ever performed.

Even though the entomological community is highly focused on the impending pollinator crisis, the public is not paying much attention.  It is not even indifference; it is just that people don’t even know about it.

The majority of studies on pollinator decline have been done in Europe and North America, which means we don’t even know how serious the problem is given that most insect biodiversity is in the tropics.

Public awareness is important because individuals can make a difference by their decisions about what flowers to plant in their gardens, which weeds to tolerate in their yards, and how to manage insect pests.

The loss of pollinators is a very serious problem, and it is not likely to get enough attention if people don’t know about it.

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Pollinators not getting the ‘buzz’ they need in news coverage

Photo, posted December 28, 2006, courtesy of Alpha via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Non-Native Plants And Insect Decline | Earth Wise

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Global insect populations have been in decline since the beginning of the 20th century.  The decline accelerated during the 1950s and 1960s, and it has reached alarming levels during the past 20 years.

The causes of plummeting insect populations include habitat destruction, deforestation, climate change, light pollution, and the rise of industrial agriculture.  This so-called insect apocalypse is being mirrored by a bird Armageddon because so many bird species depend on insects for their diets.

A still controversial, but increasingly likely factor in the decline of insect populations is the spread of non-native plants in agriculture, agroforestry, and horticulture.  A recent study published in the journal Ecological Entomology presents recent data supporting the proposition that the widespread displacement of native plants is a key cause of insect declines. 

Many insects depend on a limited number of plants for survival.  In many cases, insects’ diets are restricted to a single plant family.  When native host plants dwindle or disappear from an area, the population of insects that depend on those plants shrinks.

There are examples of insects that adopt introduced plants as food sources, such as silver-spotted skipper butterfly larvae feeding on invasive kudzu in the eastern U.S.  But generally, the widespread incursion of non-native plants is harmful to native insect populations.

Non-native plants are especially popular for horticulture.  Millions of acres of potential insect habitat have been transformed into food deserts for native insects.  The authors of the recent study recommend that Americans should extensively include native plants in their yards to help preserve insect diversity.

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How Non-Native Plants Are Contributing to a Global Insect Decline

Photo, posted May 2, 2004, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Artificial Light And Nature | Earth Wise

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Most of us are familiar with air pollution, water pollution, soil pollution, and noise pollution.  But it turns out that light can also be a pollutant as well. 

Light pollution is a consequence of industrial civilization.  Sources of light pollution include building interior and exterior lighting, advertising billboards, factories, commercial properties, streetlights, and sporting venues.      

According to findings in a new report from the University of Exeter, artificial nighttime lighting has a wide range of effects across the natural world and should be limited wherever possible.  The research team analyzed more than 100 studies and found that artificial lighting has widespread impacts on both animals and plants. 

In the study, which was funded by the Natural Environment Research Council in the U.K., researchers consistently found changes to animals’ bodies and behavior as a result of artificial lighting.  In particular, levels of the sleep cycle-regulating hormone melatonin were reduced by exposure to artificial lighting at night in all animal species studied. 

Exposure to artificial nighttime lighting also affected the timing of animals’ activities.  For rodents, which are largely nocturnal, the duration of activity was often reduced by exposure to nighttime lighting.  On the other hand, for diurnal birds, exposure to nighttime lighting led to an extension of the duration of their activities.  

Previous studies have found other wide-ranging impacts of nighttime lighting, from reducing pollination by insects to trees budding earlier in spring.  

Artificial nighttime lighting is human driven and very disruptive to the natural world.  While there’s no off switch for the planet, we could reduce the amount of light pollution drastically with no impact on our lives. 

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Artificial night lighting has widespread impacts on nature

Photo, posted July 29, 2017, courtesy of spacedust2019 via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Alien Species On The Rise | Earth Wise

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Alien species are species that are introduced, accidentally or intentionally, outside of their natural geographic range as a result of human activities.  More than 35,000 alien species have been recorded through 2005, which is the most recent year for which researchers have comprehensive global data. 

Some of the alien species go on to become invasive alien species, which can have damaging impacts on both ecosystems and economies.  In fact, alien species are one of the main drivers of plant and animal extinctions around the globe.  

According to a new study by an international research team involving University College London, the number of alien species, particularly insects, arthropods and birds, is expected to increase globally by 36% by 2050 when compared to 2005 levels.  The research was recently published in the journal Global Change Biology.

Using a mathematical model developed for the study, the researchers identified high levels of variations between regions.  For example, the largest increase in alien species by the middle of the century is expected in Europe, where numbers are predicted to jump by 64%.  The temperate regions of Asia, North America, and South America are also predicted to be hotspots of alien species.  The lowest relative increase in alien species is expected in Australia.

The researchers do not expect a reversal or slowdown in the spread of alien species.  In fact, with global transportation and trade forecasted to increase in the coming decades, they anticipate many new species will infiltrate non-native habitats by hitching rides as stowaways.   

According to the research team, it would take a concerted global effort with stricter regulations and more rigorous enforcement to slow the flow of new species. 

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Alien species to increase by 36% worldwide by 2050

Photo, posted October 3, 2016, courtesy of the Asian Carp Regional Coordinating Committee via Flickr. Photo credit: Ryan Hagerty/USFWS.

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...)