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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

Could Lyme Disease Be Eradicated? | Earth Wise

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Tiny ticks are a big problem.  Measuring only three to five millimeters in size, ticks are widely distributed around the world.  They are external parasites, feasting on the blood of birds, reptiles, amphibians, and mammals – including humans.

According to estimates from the Centers for Disease Control and Prevention, ticks infect an estimated 476,000 people with Lyme disease in the United States every year.  Lyme disease is caused by a bacterium called Borrelia burgdorferi that lurks in wild mice. Ticks that feed on the mice become infected and can then in turn infect people and animals.   

The disease is not only a problem in the United States, but in other parts of North America, Europe and Asia as well.  It often causes a characteristic “bullseye” rash and flu-like symptoms. If left untreated, it can lead to serious long-term health problems.

Currently, lyme disease is treated using antibiotics.  But antibiotics kill a wide range of bacteria – including healthy gut bacteria – which can lead to additional health issues and more antibiotic resistance.

A recent discovery by researchers from Northeastern University in Boston could allow Lyme disease to be eradicated in the wild.  The researchers found that a compound called hygromycin A is deadly to the bacterium that causes Lyme disease but harmless to animals and has little effect on most other bacteria. 

The little-known antibiotic cleared Lyme disease infection in mice, both when administered via injection and when ingested using bait.  As a result, dropping feeding baits could eradicate Lyme disease from whole areas or even entire countries.  The first field trial will be next summer.

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Drug treatment for Lyme disease could lead to its eradication

Photo, posted June 21, 2017, courtesy of NIAID via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The United States And Ticks | Earth Wise

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Tiny ticks are a big problem.  Measuring only three to five millimeters in size, ticks are widely distributed around the world.  They are external parasites, feasting on the blood of birds, reptiles, amphibians, and mammals – including humans.

According to estimates from the Centers for Disease Control and Prevention, ticks infect more than 300,000 people with Lyme disease in the United States every year, and the numbers continue to rise.  Other common tick-borne diseases include anaplasmosis, babesiosis, Rocky Mountain Spotted Fever, and powassan encephalitis.

But while the prevalence of tick-borne illnesses has steadily increased in the United States over the past two decades, a new study on tick surveillance and control “has revealed an inconsistent and often under-supported patchwork of programs across the country.”

The study, by university researchers at the CDC’s five Vector-Borne Disease Regional Centers of Excellence, is the first-ever examination of tick management programs in the United States.  The researchers found clear gaps in our public health infrastructure. 

According to the study, which was recently published in the Journal of Medical Entomology, less than 50% of public health and vector-control agencies conduct tick surveillance.  Only 25% test ticks for disease-causing germs.  And only 12% conduct or support tick-control efforts.  Researchers also discovered that the capacity for public tick-control efforts is low, as is the capacity for information and data sharing between agencies on ticks.    

The findings highlight the degree to which tick surveillance and control is lagging in the United States.  According to the research team, greater support for tick-management programs is critical, and they hope their findings will serve as a baseline from which to measure future improvements.  

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Tick surveillance and control lagging in US

Photo, posted May 4, 2009, courtesy of Jerry Kirkhart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bees And Plastic

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Wild bees in Argentina have recently been found to be constructing nests entirely made of flimsy plastic material left on farms and scientists don’t know why.

In 2017 and 2018, researchers at Argentina’s National Agricultural Technology Institute built wooden, artificial nests for wild bees.  These bee species burrow into nests to individually lay larvae rather than having a large hive with queens and workers.  The artificial nests provide hollow openings that bees generally fill with cut leaves, twigs, and mud.

Sixty-three wooden nests were constructed and three were found lined entirely with plastic.  The bees carefully cut bits of plastic in the shape and size of fingernails and arranged them in an overlapping pattern in their nests.  The plastic seems to have come from plastic bags or films, which have a similar texture to the leaves bees ordinarily use to line their nests.  And, in fact, leaves were readily available to the bees making use of plastic.

This is the first time that bees have been seen making nests entirely out of plastic, but for years scientists have known bees were incorporating plastic into their building materials.  Research is needed to determine the potential impact plastic might have on bees, but the nest building shows that bees are highly adaptive to changing environments.

Plastic often forms a threat to wildlife in the form of microplastics that can be consumed.  But there is no evidence that bees are consuming plastic.  Some researchers have speculated that the plastic in bees’ nests may form a barrier against common nest issues like mold and parasites.

At this point, it is not clear whether it is a good thing or a bad thing that some bees are choosing plastic over natural materials, but it is certainly interesting.

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Wild bees are building their homes from plastic—and scientists aren’t sure why

Photo, posted December 12, 2014, courtesy of Judy Gallagher via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Heat-Resistant Corals

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All over the world, coral reefs are being wiped out by rising sea temperatures brought about by climate change.  When sea temperatures get too high, the symbiotic relationship between coral polyps and microscopic algae living within the coral breaks down and the coral either digests or expels the algae.   The result is coral bleaching which weakens, and if it persists, kills the coral.

[Read more…] about Heat-Resistant Corals

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