Earth Wise

A look at our changing environment.

You are here: Home / Archives for mites

mites

Tourism And Invasive Species | Earth Wise

By Leave a Comment

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. 

**********

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.

Protecting Bees From Pesticides | Earth Wise

By Leave a Comment

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.

**********

Web Links

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.

Tough Times For Fireflies | Earth Wise

By Leave a Comment

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. 

**********

Web Links

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.

Another Bad Year For Bees

By Leave a Comment

The latest annual nationwide survey of beekeepers in the US revealed that honeybees are still dying off at an alarming rate.  According to the survey, beekeepers across the country lost 40.7% of their honey bee colonies from April 2018 to April 2019. 

This annual loss represents a slight increase over the average annual loss of 38.7%.  Of greater concern is that winter losses of 37.7% were the highest reported since these annual surveys began 13 years ago and are almost 9% higher than the survey average.

These results are very troubling considering that the elevated losses are continuing even after a decade of intense work trying to understand and reduce colony loss.  Evidently, there has not been much progress.

The number one concern among beekeepers is varroa mites, which are lethal parasites that can readily spread from colony to colony.  These mites have been decimating bee colonies for years.  Products developed to remove mites seem to be getting less and less effective.

But mites are not the only problem for bees.  Land use changes have resulted in reduced availability of pollen sources for bees.  Add to that pesticide exposures, environmental factors, and even problems with beekeeping practices.   In addition, extreme weather conditions such as wildfires and floods are only adding to the problems facing bees.

The tools that used to work for beekeepers seem to be failing and they are already stretched to their limits trying to keep their bees alive. Honey bees pollinate $15 billion worth of food crops in the United States each year. The problems facing bees are a problem for all of us.

**********

Web Links

U.S. Beekeepers Suffered Higher than Average Colony Loss Last Year, with Winter Losses the Highest Recorded, According to UMD-Led Annual Survey

Photo, posted June 3, 2009, courtesy of Jennifer C 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...)