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How much nanoplastic is in the oceans?

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It is unfortunately well-known that microplastics are pretty much everywhere on Earth.  They are also increasingly found in living things like birds and dolphins as well as in human brains and placentas.  The oceans are polluted with plastic, and for the first time, there is now an estimate for the volume of nanoplastics – which are even smaller than microplastics and invisible to the human eye – found in the North Atlantic.

According to a study published in the journal Nature by the microplastics and nanoplastics research group at the Helmholtz Center for Environmental Research in Germany, there are at least 30 million tons of nanoplastics in the North Atlantic, which is more than the weight of all wild land mammals on Earth.

The same researchers have analyzed plastic in lakes, urban air, and even the air in very remote places, but the new study reveals a missing part of the plastics story.

Nanoplastics are microscopic fragments smaller than one micron, about the size of small bacteria.  There has been ongoing concern about nanoplastics in ocean water, but there wasn’t the technology available to really investigate it.  While nanoplastics were expected to be found in the ocean, the sheer amount of it was surprising.

The average concentration of nanoplastics near coastlines is about 25 milligrams per cubic meter of water, about the weight of a single large bird feather.   Nanoplastics are tiny enough that they can easily infiltrate the bodies of living creatures.  For fish and other ocean animals, that means constant exposure that builds up over time.

It is highly unlikely that plastic pollution is going to stop any time soon, but there is a United Nations meeting on the subject in August in Geneva.

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Tons of Invisible Plastic Pieces Lurk in Ocean Water

Photo, posted June 24, 2020, courtesy of G.P. Schmal / NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Raccoons in Europe

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Tens of thousands of raccoons live in Kassel, a city of 200,000 people in central Germany known for its art scene.  Overall, there are an estimated 1.5 million raccoons in Germany.  The omnivorous mammals are native to North America, but they were brought to Germany in the 1930s for fur farming.  Fur farming ultimately ceased but escaping animals and intentional releases ultimately led to a large wild population of raccoons in the years afterward.

Raccoons have gradually made their way across Europe with animals spotted in France, Denmark, Poland, Italy, Austria, and elsewhere.

The people of Kassel have embraced raccoons.  In fact, the place is often called the raccoon city.  Several sports teams are named after the animals.  Many people feed them, and they are pretty much everywhere.  On the other hand, residents have to lock up their trash receptacles and they have to check under their cars before driving places.

Since 2016, the EU has classified racoons as an invasive species because of the threat they pose to native wildlife.  There are no equivalent species like them in Europe.  So, they are a threat to ground-nesting birds, bats in caves, amphibians, and more.  They are able to eat almost anything. 

What to do about raccoons in Europe is unclear.  Despite their popularity in Germany, 200,000 raccoons were culled last year.  But raccoon supporters argue that minks, which are native to Europe, and especially cats, are responsible for much of the pressure on species racoons are accused of consuming.  Meanwhile, Kassel citizens continue to enjoy their raccoons.

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Rampaging raccoons: how the American mammals took over a German city – and are heading across Europe

Photo, posted December 20, 2016, courtesy of Big Cypress National Preserve via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Toxic algae and West Coast marine life

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Over the first several months of this year, hundreds of sea lions, dolphins, and seabirds have fallen ill or died after eating sardines or anchovies that had been feeding on an algal bloom along the California coast since winter.  The biotoxin in the algae accumulates in the feeder fish.

Two cases of whales dying from the biotoxin have been confirmed by two nonprofit organizations tasked with testing dead mammals.  These were a humpback that washed ashore in Huntington Beach in January and a minke whale found dead in Long Beach in April.

This is the fourth year a row that California has experienced major algal blooms.  Warmer waters are causing blooms to be bigger and more damaging than they have been before.  They enter into new areas and contaminate the food web for longer.  The warmer waters accelerate algae growth that is further fueled by nutrients that rise to the surface from deeper colder waters driven by winds that blow parallel to the coast.  This year’s algae event started earlier than usual and is lasting longer than normal.

More than a dozen animal rescue and rehabilitation groups that form NOAA’s West Coast Marine Mammal Stranding Network are providing resources to try to respond to the situation.  At the Marine Mammal Care Center in Los Angeles, more than 80 sea lions and seals were being treated for domoic acid poisoning, the result of ingesting algae neurotoxin.  Since February, it has cared for more than 300 poisoned animals.

Marine mammals are sentinel species for humans who also consume seafood.  The West Coast ocean ecosystem is currently filled with toxins.

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California Toxic Algal Bloom Blamed for Months-long Marine Life Poisoning

Photo, posted March 26, 2025, courtesy of Marnee Jill via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Rats and climate change

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Human activity has made rats one of the most prolific mammals on the planet. Our waste, buildings, and ships provide food, shelter, and transport.  In the United States alone, rats cost the country approximately $27 billion each year in damage to infrastructure, crops, and contaminated food supplies. Additionally, rats carry and spread over 50 zoonotic pathogens and parasites, impacting public health around the world.

Now, climate change is adding to the problem. According to a new study recently published in the journal Science Advances, urban rat populations are exploding as global temperatures rise.  The researchers found that Washington DC, San Francisco, Toronto, New York City, and Amsterdam had the greatest population increases.  In fact, over the past decade, rats increased by a whopping 390% in Washington DC, 300% in San Francisco, 186% in Toronto, and 162% in New York City.  The study, which examined data from 16 cities globally, found that 11 of them showed significant increases in rat numbers.

Only Tokyo, Louisville, and New Orleans bucked the trend with declining rat numbers.

According to the researchers, the best pest management strategies involve making the urban environment less rat-friendly as opposed to removing rodents that are already there.  An example would be putting trash in containers instead of bags on the street. 

There aren’t many perks to the changing climate – unless, of course, you’re a rat. 

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Increasing rat numbers in cities are linked to climate warming, urbanization, and human population

‘Perfect rat storm’: urban rodent numbers soar as the climate heats, study finds

Photo, posted September 25, 2018, courtesy of Tim Felce via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar farms and pollinators

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Two important environmental challenges are finding some literal common ground:  the need to reduce carbon emissions and the fight to stave off global biodiversity collapse.  Both issues can be addressed at solar farms.

Solar energy is an important weapon in the battle against climate change.  But utility-scale solar farms take up large amounts of land.  Large-scale solar farms already take up nearly a thousand square miles of land in the US and will take up much more in the coming decades.

In the meantime, the biodiversity collapse is being driven in large part by habitat loss.

Given all this, solar farm operators, biologists, and environmentalists are teaming up to grow pollinator-friendly plants in and around solar farms. The plantings attract insects, birds and even mammals. The more plant diversity in the solar farms, the more environmental benefits can be achieved. 

There are costs associated with creating pollinator-friendly solar farms. Ideally, solar panels need to be installed at greater height than otherwise in order to permit growing many of the plants that attract bees and butterflies.  But there are economic benefits associated with attracting and sustaining pollinators.  On a cautionary note, there have already been cases of greenwashing, where solar operators claim environmental benefits far in excess of the scope of the actual efforts they have made. 

There are both governmental and non-governmental agencies seeking to assess and certify pollinator-friendly solar farms.  There is considerable variability in the ecological value of existing farms.  Pollinator-friendly solar farms are in their early days, but they have a lot to offer as a win-win strategy for the environment.

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Solar Farms Have a Superpower Beyond Clean Energy

Photo, posted December 4, 2014, courtesy of Juwi Renewable Energies Limited via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Seaweed On The Way | Earth Wise

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A type of seaweed called sargassum has long formed large blooms in the Atlantic Ocean.  It gets its name from the Sargasso Sea in the western Atlantic.  Since 2011, scientists have been tracking massive accumulations of the stuff each year that starts out off the coast of Africa and works its way across the Atlantic to end up in the Gulf of Mexico. 

The amount of sargassum present each year can shift depending on factors like changes in nutrients, rainfall, and wind conditions.  But since the 1980s, nitrogen content in the Atlantic has gone up by 45%.  This is likely due to human activities such as agriculture and fossil fuel production dumping materials into the rivers that feed into the ocean.

According to recent observations, the mass of seaweed now heading for Florida and other coastlines throughout the Gulf of Mexico may be the largest on record.  The giant blob of sargassum spans more than 5,000 miles in extent.  It is moving west and will pass through the Caribbean and up into the Gulf during the summer.  The seaweed is expected to become prevalent on beaches in Florida around July.

The seaweed provides food and protection for fishes, mammals, marine birds, crabs, sea turtles, and more.  But unfortunately, when sargassum hits the beaches, it piles up in mounds that can be difficult to walk through and eventually emits a gas that smells like rotten eggs.

Tourist destinations in the Caribbean region have their work cut out for them to remove seaweed that can pile up several feet deep.  For example, in Barbados, locals were using 1,600 dump trucks a day to clean their beaches.  Caribbean and Florida resorts spend millions of dollars each year to remove sargassum seaweed.

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A 5,000-mile-wide blob of seaweed is headed for Florida, threatening tourism across the Caribbean

Photo, posted February 24, 2020, courtesy of Bernard Dupont via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Humanity Weighs On The World | Earth Wise

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There are countless ways in which humankind has had disproportionate effects on our planet and most of those effects have been negative.  A recent study led by the Weizmann Institute of Science in Israel looked at the total combined weight of various groups of mammals on Earth.  The results are that human beings and our domesticated mammals are the overwhelming majority of the total mass of mammals.

We think of large land mammals – elephants, bears, bison, wildebeests, and so on – as adding up to a massive amount of animal matter.  The study determined that all wild land mammals put together add up to about 22 million metric tons. Wild marine mammals – such as dolphins and whales – add up to about 40 million tons in total.  These sound like pretty big numbers until we look at the human and human-created side of the equation.

The study found that humans weigh about 390 million metric tons, while domesticated mammals – like sheep, cows, and pigs as well as dogs and cats – weigh about 630 million metric tons combined.

All told, wild mammals account for only 6% of all mammals by weight.   People and their domesticated animals make up the other 94%.  This enormous imbalance is an indication of how profoundly humans have reshaped life on Earth.  House cats total twice the weight of African elephants and pigs add up to twice the weight of all wild land animals combined.

The conclusion to draw from the big picture here is that wild animals on Earth are not doing very well.  We already knew this from many other perspectives, but this census by weight presents a stark picture of the extent to which we have taken over the planet and its ecosystems.

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Total Weight of Wild Land Mammals Less Than One-Tenth Weight of All Humans

Photo, posted December 27, 2006, courtesy of Nigel Hoult via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

Tick-Borne Pathogens In Canada | Earth Wise

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Measuring only three to five millimeters in size, tiny ticks are a big problem.  They are widely distributed in many parts of the world, especially in warm and humid climates.  Ticks are arachnids – not insects – meaning they’re more closely related to spiders than to flies or mosquitos.  They are external parasites that feast on the blood of birds, reptiles, amphibians, and mammals – including humans.

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

Ticks are becoming a problem in Canada as well.  According to a new study by researchers from McGill University and the University of Ottawa, tick-borne pathogens are on the rise in Central Canada – a region where ticks were never previously detected. 

In the study, the researchers collected ticks across Ontario and Quebec.  They found that five emerging pathogens were present across their study sites, including the pathogens that cause Lyme disease and babesiosis.  The researchers also found that pathogens can transmit in different ways.  Typically, pathogens are transmitted to a tick after feeding from the blood of an infected host, like a small mammal.  But the research team found evidence of pathogens that could be directly transmitted from adult female ticks to larval ticks.

According to the researchers, more comprehensive testing and tracking is needed to detect the spread and risks of tick-borne pathogens to humans and wildlife in Canada.

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Tick-borne pathogens increasingly widespread in Central Canada

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

Earth Wise is a production of WAMC Northeast Public Radio

The Living Planet Index | Earth Wise

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The World Wildlife Fund and the Zoological Society of London recently published the latest Living Planet Index, which is designed to measure how animal populations are changing through time.  The purpose is to provide an assessment of the health of ecosystems and the state of biodiversity.

The LPI only looks at the population of vertebrates:  birds, mammals, reptiles, amphibians, and fish.  The latest survey looked at how populations have changed between 1970 and 2018.  The results are that populations of these animal groups have declined by an average of 69% over that 48-year period.

This result highlights a very real and very severe crisis of biodiversity loss.  However, it does not mean that there are 2/3 fewer animals today than 48 years ago.  The way the index is calculated is to look at the changes in individual populations of over 5,000 different species.  Then these individual relative declines are averaged to get the result.  

There are shortcomings in the LPI.  For example, individual species that have seen massive population declines will bring the average down.  But even removing the outliers both of a negative and a positive impact does not dramatically change the result.

There is no perfect indicator for biodiversity and ecosystem health.  The Living Planet Index is nonetheless a useful metric and indicates that many species around the world are in decline.  Policymakers and environmental advocates need to make decisions about conservation and protection measures and this index is one tool they can use.

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There’s a frightening new report about wildlife declines. But many are getting the story wrong.

Photo, posted October 12, 2019, courtesy of Visit Rwanda via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Coping With Climate Change | Earth Wise

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Extreme weather events including prolonged drought and heavy rainfall are becoming more common and more severe as global temperatures rise.  As the climate continues to change in the coming decades, how will animals respond? 

Researchers from the University of Southern Denmark have examined how different mammals react to climate change. They analyzed data on population fluctuations from 157 mammal species around the world.  They compared these fluctuations with weather and climate data from the same time period.  The research team had 10 or more years of data for each species studied. 

The researchers found that mammals that live for a long time and/or produce less offspring –  like llamas, elephants, bears, and bison – are more climate resilient than small mammals with short lives — like mice, possums, lemmings, and rare marsupials. 

For example, large, long-lived mammals can invest their energy into one offspring, or simply wait for better times if conditions become challenging.  On the other hand, small, short-lived mammals like rodents have more extreme population changes in the short term. In the event of a prolonged drought, large portions of their food base may rapidly disappear, and they are left to starve because they have limited fat reserves.

However, the research team notes that the ability of a species to withstand climate change must not be the only factor when assessing a species’ vulnerability.  In fact, in many cases, habitat destruction, poaching, pollution, and invasive species pose a larger threat to animal species than climate change. 

While the study only examined 157 species, the findings enable researchers to also predict how animals they know less about will react to climate change.

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Which animals can best withstand climate change?

Photo, posted July 8, 2018, courtesy of Ray via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Resurrecting The Tasmanian Tiger | Earth Wise

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Tasmanian tigers earned their nickname because of the stripes along their back, but they were not felines.  In fact, they were carnivorous marsupials, the type of Australian mammal that raises its young in a pouch.

Tasmanian tigers, also known as thylacines, were once native to the Australian mainland, as well as the islands of Tasmania and New Guinea.  Dog-like in appearance, Tasmanian tigers were extensively hunted after European colonization.  The last known Tasmanian tiger died in captivity in 1936.

Nearly 100 years after its extinction, the Tasmanian tiger may live once again.  Scientists in Australia and the United States have launched an ambitious multimillion dollar de-extinction project to genetically resurrect the Tasmanian tiger.

In order to bring back the animal, researchers will have to take stem cells from a living species with similar DNA – like the fat-tailed dunnart – and use gene editing techniques to turn them into “Tasmanian tiger” cells – or the closest approximation possible.  The team will need new assisted reproductive technologies to use the stem cells to make an embryo, which will then have to be transferred into an artificial womb or a dunnart surrogate to gestate.  The research team is optimistic that there could be a hybrid baby Tasmanian tiger in 10 years. 

The ambitious project is a partnership between scientists at the University of Melbourne and the Texas-based company Colossal Biosciences.  This is the second de-extinction undertaking by Colossal Biosciences, which announced last year it planned to use its technology to recreate the woolly mammoth, and return it to the Arctic tundra.

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Scientists want to resurrect the extinct Tasmanian tiger

Tasmanian tiger: Scientists hope to revive marsupial from extinction

Photo credit: E.J. Keller, from the Smithsonian Institution archives, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Red Pandas And Climate Change | Earth Wise

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Red pandas are small mammals native to the mountainous forests of China, India, Nepal, Bhutan, and Myanmar.  Unlike their name suggests, they are not related to giant pandas.  In fact, red pandas are distant relatives of raccoons. Renowned for their tree-climbing abilities, red pandas live at moderately high elevations in the Himalayas where they forage widely for bamboo shoots and various fruits.

According to the International Union for the Conservation of Nature, red pandas are endangered.  Scientists estimate that there are less than 10,000 red pandas remaining in the wild today, and these numbers are continuing to fall. 

Habitat loss is the main threat to red panda’s survival.  Human expansion into the area, combined with the effects of climate change, has led to the fragmentation and loss of livable land.  Red pandas also face dangers from hunting and poaching.

According to new research recently published in the journal Landscape Ecology, human impacts are driving red pandas closer to extinction than previously thought.  Using GPS telemetry, a research team from the University of Queensland in Australia tracked red pandas in Nepal over a 12-month period.  The researchers found that human activities, such as infrastructure development, were causing red pandas to restrict their movements, which is further fragmenting their habitat and interfering with natural interactions between the animals. 

As the amount of wild forest dwindles, red pandas are being forced into situations where they must decide whether to live closer to predators or adapt to co-exist with humans.

The research team recommends minimizing human-induced disturbances in red panda habitats and to maintain habitat continuity in ecologically sensitive areas. 

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Red pandas face a fractured future

IUCN: Red Panda

Photo, posted November 27, 2016, courtesy of Mathias Appel 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.

Octopuses And Litter | Earth Wise

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Octopuses are remarkably intelligent animals.  They have a larger brain for their body size than all other animals apart from birds and mammals.  They exhibit high-order cognitive behaviors including tool use and problem solving.  Some captive octopuses learned to shoot jets of water at aquarium light switches to turn them off.  Others have learned to unscrew jar lids to get at food.

A recent analysis of underwater imaging has shown that octopuses are increasingly using discarded bottles, cans, and other human-generated litter as shelter or as a place to lay eggs.

The research documented 24 species of octopus sheltering inside glass bottles, cans, and even an old battery.  Some buried themselves under a mixture of bottle caps and seashells.  Others even carried plastic items around while walking on just two tentacles to disguise themselves from predators.

The octopuses showed a preference for unbroken items and for darker or opaque containers.  Normally, octopuses make use of natural shelters such as seashells.  Whether they are making use of litter simply because there is so much of it around or because there is an increasing lack of natural items is not clear.

As with all other aspects of the growing problem of litter in the oceans, this new trend is not a good one.  Sheltering or laying eggs inside discarded tires, batteries, or plastic items has the potential to expose octopuses to heavy metals and other harmful chemicals.

Octopuses are intelligent and resourceful animals, and they will use whatever they have at their disposal to continue sheltering or moving around with protection from potential predators.

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Octopuses Have Learned to Make Use of Ocean Litter, Study Finds

Photo, posted May 13, 2014, courtesy of Elias Levy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Armadillos Heading North | Earth Wise

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Armadillos are small mammals known for their unique armor-like shell and their digging habits.  There are 21 species, primarily native to South America.  Some species have expanded northward due to their rapid breeding cycle, adaptability, and reduced number of predators.  Only one species – the nine-banded armadillo – is found in the United States.  In fact, it is the official small mammal of the state of Texas.

Over time, armadillos have expanded their range to states in the Deep South.  More recently, the animals have been pushing further north.  Milder winters in the changing climate have allowed them to inhabit new areas, including parts of the Blue Ridge Mountains. They were first sighted in North Carolina in 2007 and their numbers have recently been growing in the western half of the state.

There are now armadillos as far north as Missouri, Nebraska, and Iowa, and there is little to halt their further advance.  They are able to hold their breath for six minutes at a time, so they can cross rivers by walking along the bottom or by inflating their intestines and floating across the top.  Their hard shell provides protection from predators.  They reproduce prolifically.  Females give birth to quadruplets multiple times over the course of their 12-15-year lifespan.

Armadillos are fun to look at, but they are a nuisance where people live.  They are prone to digging holes in lawns.  In parts of North Carolina, some people have placed bounties on the animals.  They are difficult to trap and there aren’t common repellents for them.  As the climate continues to warm, it is only a matter of time before the range of armadillos expands into other states.

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Armadillos Advance Northward As Temperatures Rise

Photo, posted May 2, 2017, courtesy of Gail Hampshire via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Manatees And Pollution | Earth Wise

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Manatees are large, gentle, and curious marine mammals measuring up to 13 feet long and weighing up to 3,300 lbs.  There are three living species of manatees:  The Amazonian Manatee, the West African Manatee, and the West Indian Manatee, which is commonly found in Florida and the Gulf Coast.  Manatees inhabit the shallow, marshy coastal areas and rivers of the Caribbean Sea, the Gulf of Mexico, the Atlantic coast, the Amazon basin, and West Africa. 

The West Indian Manatee, which includes the Florida Manatee, is protected under the Endangered Species Act.  Today, the range-wide population is estimated to be at least 13,000 manatees, with more than 6,500 in the southeastern United States and Puerto Rico.

In Florida, an uptick in nutrient loading from nonpoint sources is triggering algal blooms in Indian River Lagoon and neighboring areas.  These algal blooms have decimated seagrass, manatees’ primary food source. 

As a result , manatees have starved to death by the hundreds along Florida’s east coast.  The state has recorded 974 manatee deaths in 2021, shattering previous annual all-time highs with still approximately two months to go.  Manatees, which need to eat between 100-200 pounds of seagrass daily, are now eating the seagrass roots, which permanently kills the aquatic plants.

Efforts are being made to replant seagrass and to restore clam and oyster beds so that the mollusks can help clean the water.  But manatees face a myriad of additional threats, including collisions with boats and ships, temperature changes, disease, and crocodile predation.

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Florida lawmakers hear Fish & Wildlife agency response to manatee death ‘catastrophe’

West Indian manatee

Preliminary 2021 Manatee Mortality Table by County

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

Earth Wise is a production of WAMC Northeast Public Radio.

What Does Conservation Really Mean? | Earth Wise

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There is a great deal of interest in protecting nature and, in many cases, restoring aspects of nature that have been lost.  But what do these things really mean?

What is most important?  Protecting iconic species?  Strengthening nature’s resilience?  Several recent scientific papers address these questions and come up with rather different answers.

It isn’t even clear what constitutes a pristine ecosystem.  According to some experts, ecosystems that have lost most of their large mammal species, for example, cannot be considered intact.  By that standard, only a tiny fraction of the world’s ecosystems remains intact.

Other experts contend that preserving individual species is not what really matters.  Studies have shown that many ecosystems have undergone and continue to undergo massive species shifts over time with frequent extinctions along the way.  Nevertheless, the ecosystems continue to flourish with new species replacing others to perform the various functions required.

Some perspectives consider intact ecosystems to be those devoid of human influence.  But that notion is not universally held.   There is the idea that most of the world’s ecosystems were essentially untouched until perhaps 500 years ago when European exploration expanded greatly.  But the reality is that even 12,000 years ago, nearly three-quarters of terrestrial nature was inhabited, used, and shaped by people.  However, those human interactions were similar to how many indigenous and local peoples across the globe still live, not like the interactions of modern civilization that result in massive changes to ecosystems.

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Species or Ecosystems: How Best to Restore the Natural World?

Photo, posted November 21, 2003, courtesy of Megan Coughlin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climbing To Escape The Heat | Earth Wise

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Colorado has warmed by nearly 3.5 degrees Fahrenheit since the 1980s because of human-caused climate change.   As a result, many mammal species have shifted uphill to escape the heat.

The golden-mantled ground squirrel is a popular sight among tourists in the Rocky Mountains.  It is one of the most photographed animals there as they pose on rocks near roadsides and in campgrounds.  According to University of Colorado research recently published in the journal Ecology, these squirrels have shifted their range upward by 659 feet.  The new study looked at the ground squirrels along with 46 other small mammals.  On average, these animals have shifted their range upward by more than 400 feet since the 1980s.

The researchers visited multiple sites in Colorado’s Front Range and San Juan mountains over the course of several years to collect records of the current ranges of these 47 animals. They then compared the findings from their surveys to over 4,000 historic records from collections dating back to the 1980s.

The researchers expected to see some changes, but not of the magnitude they observed.  For example, before 1980, the pygmy shrew was never detected above about 9,800 feet in elevation.  Today, its maximum extent is more than 11,800 feet.

Montane mammals – which are those who already live at higher elevations – have moved up an additional 1,100 feet on average.  If this trend continues, some animals and even entire communities may be pushed to the tops of mountains with nowhere else to go.  According to the researchers, the study paints a stark picture of a mountain range in crisis.

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Small mammals climb higher to flee warming temperatures in the Rockies

Photo, posted September 6, 2002, courtesy of Franco Folini via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Assisting Evolution | Earth Wise

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As plants and animals around the world grapple with climate change, invasive species, disease, and other threats, conservationists grapple with the issue of what it means to protect what is natural and how far to go to prevent extinctions.

Australia is where many of these issues have risen to the forefront.  Imported mammals – particularly cats and foxes – have decimated many of Australia’s indigenous marsupials.  Much of the focus for decades has been on killing off the invaders and cordoning off protected animals.  In recent years, however, there have been efforts to expose prey animals to limited numbers of predators to develop prey populations that are better equipped to survive among predators.  Getting rid of all the predators is not realistic.  Saving species may require helping them to adapt.

On the Great Barrier Reef, where half its coral populations have perished because of rising water temperatures, scientists are breeding corals that are more heat tolerant.  They are even considering the use of gene editing technology to “assist evolution” in developing corals that can survive in a changing world.

At SUNY College of Environmental Science and Forestry in Syracuse, New York, researchers have produced a genetically modified American chestnut tree that is resistant to chestnut blight, the fungal pathogen that killed off nearly every chestnut tree in North America in the early 20th century.

The idea of conservation is to protect what is natural in our world.  However, at a time when there are unprecedented threats to so many species, the distinction between what is natural and what is artificial may no longer provide a sound guide to what should be done to protect life on earth.

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Assisting Evolution: How Far Should We Go to Help Species Adapt?

Photo, posted November, 2000, courtesy of Bernard Dupont 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...)