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Sand mining and the environment

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Sand mining is the world’s largest mining endeavor.  It is responsible for 85% of all mineral extraction.  It is also the least regulated, possibly the most corrupt, and likely the most environmentally destructive.  Sand is the second-most exploited natural resource in the world after water.  Its global use has tripled in the past two decades.  More than 50 billion tons of sand is extracted from the environment each year.

Sand plays a critical role in much of human development around the world.  It is a key ingredient of concrete, asphalt, glass, and electronics.  It is relatively cheap and relatively easy to extract.  But we use enormous amounts of it.

Sand mining is a major threat to rivers and marine ecosystems.  It is linked to coastal erosion, habitat destruction, the spread of invasive species, and damage to fisheries. 

The harm from sand mining is only beginning to attract widespread attention.  A recent study by an international group of scientists published in the journal One Earth identifies        threats posed by sand mining.  Sand extraction in marine environments remains largely overlooked, despite sand and sediment dredging being the second most widespread human activity in coastal areas after fishing.

Sand is generally seen as an inert, abundant material, but it is an essential resource that shapes coastal and marine ecosystems, protects shorelines, and sustains both ecosystems and coastal communities.  Sand extraction near populated coastlines is particularly problematic as climate change makes coastlines increasingly fragile.

Like all other resources on our planet, even sand cannot be taken for granted.  It must be responsibly managed.

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The rising tide of sand mining: a growing threat to marine life

Photo, posted February 7, 2013, courtesy of Pamela Spaugy / U.S. Army Corps of Engineers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Species range and climate change

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The geographic range of a particular plant or animal species is the area in which it can be found during its lifetime.  The range of most species is limited by climatic factors, including temperature, precipitation, soil moisture, humidity, and wind.  Any changes in the magnitude or variability of these factors will impact the species living there. 

For example, a species sensitive to temperature may respond to a warmer climate by moving to cooler locations at higher latitudes or elevations. 

But not all species are able to move at the same speed.  According to an international research team led by scientists from the University of Massachusetts Amherst, non-native species are expanding their ranges many times faster than native species.

The researchers found that land-based plant and animal species need to be shifting their ranges by about two miles per year just to keep up with the rapid pace of the changing climate.  Marine species need to be moving about 1.7 miles per year.  However, native species are only managing to move about one mile per year on average.  

Non-native species, on the other hand, are spreading nearly 22 miles each year on their own.  Additionally, when the role humans play in assisting the spread of non-native species is factored in, the rate jumps to a whopping 1,170 miles per year.  This is more than 1,000 times faster than the rate at which native species are spreading.   

The researchers conclude that there is no chance for native species to keep up with climate change without human help.  Assisted migration needs to be on the table if native plants and animals are to survive.   

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Non-Native Plants and Animals Expanding Ranges 100 Times Faster than Native Species

Photo, posted April 10, 2011, courtesy of Bri Weldon via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Cost Of Invasive Species | Earth Wise

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According to a new report published by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services for the United Nations, invasive species introduced to new ecosystems around the world are causing more than $423 billion in estimated losses to the global economy every year.  These economic costs are incurred by harming nature, damaging food systems, and threatening human health.

According to the report, these costs have at least quadrupled every decade since 1970 and the estimates are actually conservative because it’s difficult to account for all of the effects of invasive species.

The report estimates that humans have intentionally or unintentionally introduced more than 37,000 species to places outside their natural ranges.  More than 3,500 of them are considered invasive because they are harmful to their new ecosystems.  Invasive nonnative species were a major factor in 60% of known extinctions of plants and animals.

Some species are relocated deliberately by the wildlife trade and international shipping.  Other plants and animals end up hitching a ride with ordinary travelers as they move about by car, boat, plane, or train. 

Invasions can damage human health.  Mosquitos that transmit diseases like malaria, dengue fever, and the Zika virus have become invasive around the world. The wildfires in Hawaii this summer were fueled by invasive nonnative grasses in a warming climate. 

Nearly every country in the world has agreed to participate in a sweeping agreement to preserve biodiversity and reduce invasive species.  It is an essential global goal.

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Invasive Species Are Costing the Global Economy Billions, Study Finds

Photo, posted June 2, 2022, courtesy of Sam Stukel (USFWS) via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Why Are Insect Populations Declining? | Earth Wise

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The world is experiencing a decline in overall insect populations as well as a collapse in insect diversity.  A recent special issue of the journal Biology Letters discusses the major causes of this alarming trend.

According to the study, the primary causes of the worldwide decline in insect biomass are land-use intensification in the form of greater utilization for agriculture and building development, climate change, and the spread of invasive animal species as a result of human trade.

The study concludes that it is not just these factors that are driving the global disappearance of insects, but also that these three factors are interacting with each other.  For example, ecosystems that are deteriorated by humans are more susceptible to climate change and so are their insect communities.  Similarly, invasive species can establish themselves more easily in habitats damaged by human land-use and displace native species.  Many native insect species decline or go extinct while others – often invasive species – thrive and increase, leading to decreasing insect diversity.  Warming temperatures are making many locations undesirable for various insect species and they often cannot migrate to anyplace better.

Declining insect populations and diversity results in concomitant declines in plant species that depend on pollinators.  This in turn threatens the stability of entire ecosystems.

The researchers advocate for continued monitoring of insect diversity across many habitats and countries and propose the creation of a network of interconnected nature reserves such that species can move from one to another. 

We often think of insects as pests, but they are a crucial part of the world’s ecosystems.

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The reasons why insect numbers are decreasing

Photo, posted April 17, 2011, courtesy of Dean Morley 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.

The Cost Of Invasive Species | Earth Wise

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A new study published in Nature has tried for the first time to put a price tag on the impact of invasive species.  Researchers have been studying the effects of invasive species for decades, but it is a problem that has not really captured the attention of the public and policy makers.

According to the research by scientists at the French National Museum of Natural History, from 1970 to 2017, invasive species have cost the global economy at least $1.28 trillion dollars in damages and efforts to control them.

The team screened over 19,000 published papers, ultimately analyzing nearly 2,000 that detailed costs of various invasions at particular times.   Annual costs roughly doubled every six years, reaching a yearly bill of $162 billion in 2017.

The five costliest invasive species are Aedes mosquitos, rats, cats, termites, and fire ants, collectively accounting for a quarter of the global damage.

Asian tiger mosquitos and yellow fever mosquitos alone accounted for $149 billion in damage to public health as they spread from country to country.  Rats hitchhike on human boats and drive native species to extinction on islands around the world.  Cats inflict damage primarily by their impact on native biodiversity.  By some estimates, they kill a billion birds each year in the US alone.   Termites, as they spread across the globe, wreak havoc on all sorts of infrastructure.  Fire ants can feed on a variety of seedlings, from citrus to soybeans, reduce the size of grazing lands for livestock and bite and sting farm animals and humans.

The study shows invasive species are a massive problem that is getting worse.

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Invasive Species Cost Billions of Dollars in Damages Annually, Researchers Find

Photo, posted March 29, 2012, courtesy of Aleksey Gnilenkov 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.

Monster Tumbleweeds

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Tumbleweeds have long been seen as symbols of America’s old west.  Tumbleweeds are a structural part of the above-ground anatomy of a number of species of plants known as diaspores.  Diaspores are essentially seed dispersal units.  In a few seed plants, they comprise most or all of the plant.  Once they are mature and dry, they detach from the roots and roll around due to the force of the wind.

There is a new species of gigantic tumbleweed – the Salsola ryanii – that is expanding its territory in the American west.  It is the result of a relatively unusual genetic process known as polyploidy, which produces offspring with multiple sets of chromosomes.  Researchers believe that that the new hybrid species of tumbleweed is healthier than earlier versions.  As a result, one geneticist described Salsola ryanii as a nasty species replacing other nasty species of tumbleweed in the US.

These tumbleweeds can grow up to 6 feet tall.  Tumbleweeds in general are invasive plants that cause traffic accidents, damage agricultural operations, and cause millions of dollars in property damage.  Last year, the town of Victorville in the California desert was buried in them, piling up to the second story of some houses.

Salsola ryanii has a relatively small range, but it is expanding rapidly.  The new study determined that it is more vigorous than its predecessors, which are invasive in 48 states.  The plant is an annual but tends to grow on the later side of winter.  It is one of the only things that is still green in late summer.  With summer rains increasing as the climate changes, these monster tumbleweeds are poised to wreak havoc.   The experts are warning that there should be efforts to suppress them before they take over.

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Monster tumbleweed: Invasive new species is here to stay

Photo, posted February 27, 2018, courtesy of Tracie Hall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Exotic Pets Can Become Problems

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Each year, millions of exotic animals are sold as pets around the world.  The term “exotic” lacks a set definition but is generally used to refer to an animal that’s wild or more unusual than standard pets, like cats and dogs. 

The exotic pet trade is a multi-billion dollar industry,  involving tens of millions of individual animals from thousands of species, including reptiles, amphibians, fish, birds, and mammals.

Some of the exotic pet trade is legal, but a lot of it isn’t.  Many animals are illegally captured from the wild to meet the global demand for exotic pets. 

People often purchase exotic animals without completely understanding the consequences.  Some exotic pets, for example, can live nearly twice as long as the average dog.  Caring for exotic pets can be both expensive and risky, since they are largely undomesticated (and therefore can have unpredictable behavior).

As a result, it’s not uncommon for owners to release exotic pets intentionally.  When this happens, the consequences can be catastrophic.  Sometimes the animal dies from starvation or predation, but in other instances, the animal proliferates and becomes an invasive species.

Invasive species are the second largest driver of biodiversity loss worldwide, and they cost the U.S. $120 billion a year. 

According to an academic review recently published in the journal Frontiers in Ecology and the Environment, the exotic pet trade is one of the primary causes of the spread of invasive species and has fueled the establishment of hundreds of them.  Tegus, Burmese pythons, and red lionfish are examples of pets-turned-pests. 

The best way to combat this trend is through education, detection, and rapid response. 

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Why you should never release exotic pets into the wild

Photo, posted September 19, 2010, courtesy of Mike Baird via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shipping And Invasive Species

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The increasing numbers of invasive species around the world are a major driver of biodiversity change and cause billions of dollars in economic damages annually.  Climate change is a major factor in the spread of invasive species, but a new study by McGill University suggests that global shipping growth will far outweigh climate change in the spread of non-indigenous pests to new environments in the coming decades.

One of the most significant ways in which the disparate regions of the world are interconnected is via transportation networks.   The global shipping network is the primary means by which materials and goods are moved worldwide, accounting for over 80% of world trade.  And for this reason, the global shipping network is responsible for much of the introduction of non-indigenous species across the planet.

Living organisms are often transported through ballast water, which is taken up to stabilize cargo vessels.  Other species are transported by biofouling, whereby they attach to the hulls of ships.  Taken together, these two pathways account for anywhere between 60 and 90% of marine bioinvasions.   (Terrestrial invaders are generally moved as a byproduct of shipping, for example by infesting wood packaging material).

The McGill study looked at trends in global shipping and how socioeconomic factors are driving change.  For example, China’s share of global container throughput has gone from 1.4% in 1990 to 20.1% in 2013.  So, the distribution and patterns of shipping have been changing dramatically and with it the spread of non-indigenous species.

Awareness of this issue is increasing.  For example, there have been policy initiatives such as the International Ballast Water Management Convention that is an effort to control bio-invasions through measures such as ballast exchange.  We need to take measures to limit the unintentional spread of species.

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Global forecasts of shipping traffic and biological invasions to 2050

Photo, posted December 3, 2009, courtesy of Roger W via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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