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Rewilding The American West | Earth Wise

September 14, 2022 By EarthWise Leave a Comment

Oregon State University scientists have proposed a series of management changes for western federal lands aimed at re-establishing ecosystems there. Their proposal would result in more gray wolves and beavers in nearly 200,000 square miles of federal lands in 11 states.

In each of those states, the researchers identified areas containing prime wolf habitat. Gray wolves were hunted to near extinction in the West but have been gradually reintroduced in some areas starting in the 1990s. Wolf restoration offers significant ecological benefits by helping to naturally control the population of grazing animals such as elk. This in turn facilitates the regrowth of vegetation species such as aspen, which ultimately supports diverse plant and animal communities.

Beaver populations, which used to be robust across the West, declined roughly 90% after settler colonialism and are now nonexistent in many areas. By felling trees and shrubs and constructing dams, beavers enrich fish habitat, increase water and settlement retention, maintain water flows during droughts, and increase carbon sequestration.

According to the researchers, the biggest threat to these western lands is livestock grazing, which has degraded ecosystems to a great extent. They recommend the removal of grazing on about 30% of the federal lands being used for that purpose and instead would have rewilding efforts go on.

The American West is going through a period of converging crises including extended drought and water scarcity, extreme heat waves, massive fires, and loss of biodiversity. Rewilding is a way to reestablish long-standing ecosystems.

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More wolves, beavers needed as part of improving western United States habitats, scientists say

Photo, posted October 1, 2020, courtesy of Tina DaPuglet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Cotton More Sustainable | Earth Wise

August 16, 2022 By EarthWise Leave a Comment

In the United States, cotton is a $7 billion annual crop grown in 17 states. Cotton plants in the largest producing countries in the world – India, China, and the U.S. – are genetically very similar and, like other crops that lack diversity, can be at risk.

Cultivated cotton around the world has been bred to look and act very similar. It is high yielding and easy to harvest using machines. But it is also wildly unprepared to fight disease, drought, or insect-borne pathogens.

Researchers are looking beyond breeding for ways to combat the low genetic diversity of cultivated cotton. There are new approaches that combine breeding with elements of genetic modification. Most cotton in the U.S. has already been genetically modified to resist caterpillar pests. But as new problems emerge, new solutions will be needed that may require complicated changes to the cotton genome. Getting regulatory approval for a genetically modified crop is a long and expensive process.

However, ordinary genetic modification is not the only possibility. Modern genetic sequencing technology can allow researchers to examine various wild cotton varieties and identify the genetic markers for desirable traits. Once valuable genes in wild species have been identified, traditional plant breeding techniques could be used to produce cultivated cotton varieties that are more resistant to disease and drought.

Climate change is raising average global temperatures and some important cotton-producing regions such as the U.S. Southwest are becoming drier. Researchers are hoping to produce cultivated cotton that can tolerate drought at the seedling stage. The ultimate goal is to create more sustainable and genetically diverse cotton that can thrive in a changing world.

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Cotton Breeders Are Using Genetic Insights To Make This Global Crop More Sustainable

Photo, posted November 9, 2008, courtesy of BP Takoma via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Red Pandas And Climate Change | Earth Wise

July 6, 2022 By EarthWise 2 Comments

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.

Large Mammals And Climate Change | Earth Wise

April 14, 2022 By EarthWise Leave a Comment

The natural world has an important part to play in mitigating the effects of climate change. We mostly think about the role of plant life which absorbs carbon in trees, grasses, and other flora. However, a new study published by Oxford University looks at the role of large wild animals in restoring ecosystems and reducing the effects of climate change.

According to the study, there are three important ways in which large animals such as elephants, rhinos, giraffes, whales, bison, and moose can potentially mitigate the effects of climate change: carbon stocks, albedo, and fire regimes.

When large herbivores graze, they disperse seeds, clear vegetation, and fertilize soil. All of these things build more complex and resilient ecosystems which helps to maintain and increase carbon stocks in the soil and in plant tissues thereby helping to reduce CO2 in the atmosphere.

Grazing large animals trample vegetation which opens up areas of dense vegetation to create open mixes of grass and shrubs and can reveal snow-covered ground in cold regions. Such open habitats are lighter in color (higher in albedo) and reflect more solar radiation into the atmosphere, cooling the Earth’s surface rather than heating it up.

Large grazing animals can lessen wildfire risk by browsing on woody vegetation that would otherwise fuel the fires and also by creating paths that act as firebreaks.

In marine ecosystems, whales and other large animals fertilize phytoplankton, which capture some 37 billion tons of CO2 each year.

Overall, large animals are an important part of the natural world’s ability to reduce the effects of the changing climate by helping with localized adaptation to the changes taking place in ecosystems.

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Large mammals can help climate change mitigation and adaptation

Photo, posted August 20, 2017, courtesy of Jon Niola via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Koalas Are Endangered | Earth Wise

March 22, 2022 By EarthWise Leave a Comment

The koala is one of the world’s most iconic animal species and is widely considered to be the symbol of Australia. Koalas are not bears; they are marsupials.

Being iconic symbols is not sufficient to prevent koalas from going extinct. In the 1920s, hundreds of thousands of koalas were shot for the fur trade, greatly reducing their population.

More recently, drought, bush fires, disease, and habitat loss have drastically reduced the numbers of koalas. Since 2018, there has been a 30% decline in koala populations across Australia. It is difficult to get an accurate count of the animals because they don’t move around much, and they live high up in tree canopies where they are hard to spot.

Estimates are that the koala population has dropped from between 45,000-82,000 in 2018 to between 32,000-58,000 in 2021. The koala is now extinct in 47 Australian electorates and in many others, there are only handfuls of animals remaining. The population decline was accelerated by devastating wildfires in late 2019 into early 2020. Some estimates are that koalas could be extinct by 2050. Conservation organizations around the world have been demanding greater protection for koalas for years.

Given this dire situation, the Australian government recently declared the koala an endangered species, reclassifying it from being a vulnerable species. The government plans to adopt a recovery plan that will include new laws protecting koalas and their natural woodland environments. The details of the plan remain to revealed.

According to the Australian Koala Foundation, however, the new status of the koala means very little in and of itself. If the clearing of the koala habitat continues, the species has little chance of surviving in the wild.

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‘In rapid decline’: Australia has lost 30% of its koalas in just 3 years, foundation says

Australia Declares Koalas an Endangered Species

Photo, posted September 18, 2019, courtesy of Guido Konrad via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Alaskan Icemageddon | Earth Wise

January 25, 2022 By EarthWise 1 Comment

December saw some wild weather in Alaska. A combination of record high temperatures and torrential rainstorms resulted in the coining of the term “Icemageddon” to describe what was going on with the weather.

Kodiak Island in southern Alaska saw a high temperature of 67 degrees on December 26, which was warmer than it was in Southern California that same day. This set an all-time record for the warmest December day in Alaska. Such a high temperature is amazing considering how little sunlight Alaska gets at this time of year. And with warmer air comes wetter air, as the atmosphere is capable of holding more water vapor as temperatures increase.

As a result, that same day saw the interior of the state get an inch of rain in just a few hours, something that hadn’t happened for decades. But then, when temperatures plummeted again, all that rainwater froze.

Huge sheets of ice blocked roads and choked traffic in Fairbanks, Alaska’s second largest city. Indeed, it was the state’s transportation department that came up with the term icemageddon to describe the situation.

The extreme warmth in December is related to the same weather pattern that brought cold, wintry weather to the Pacific Northwest and Northern California. Those weather conditions resulted in hundreds of cancelled flights in Seattle, where temperatures dropped into the 20s, and in massive amounts of snowfall in the Sierra Nevada mountains in California. A strong area of high pressure anchored in the Northern Pacific resulted in a clockwise flow around it drawing warmer, more tropical air from the Pacific up to Alaska.

Climate change continues to push the envelope on what sort of weather is possible all over the world.

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Alaska faces ‘Icemageddon’ as temperatures swing wildly

Photo, posted April 30, 2015, courtesy of Naql via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Capturing Methane To Feed Fish | Earth Wise

December 30, 2021 By EarthWise Leave a Comment

Methane in the atmosphere is an extremely potent greenhouse gas. Its warming potential is about 85 times that of carbon dioxide over a 20-year period. It also worsens air quality by increasing atmospheric ozone. Many human activities add methane to the atmosphere, notably emissions from landfills and oil and gas facilities.

Capturing methane from these sources for subsequent use is currently uneconomical but new research from Stanford University analyzes the market for using the methane to feed bacteria to produce fishmeal.

Methane-consuming bacteria called methanotrophs can be grown in chilled, water-filled bioreactors containing pressurized methane, oxygen, and nutrients. The bacteria produce a protein-rich biomass that can be used as fishmeal in aquaculture. This could offset demand for fishmeal made from small fish or plant-based feeds that require land, water, and fertilizer.

Some companies already do this using natural gas provided by utility pipelines, but it would be far better for the environment to use methane emitted at large landfills, wastewater treatment plants, and oil and gas facilities.

Consumption of seafood has more than quadrupled since 1960, depleting wild fish stocks. Farmed fish now provide half of all the animal-sourced seafood we eat.

The Stanford research analyzed the cost of methanotrophic fishmeal production under various scenarios and found it to be very competitive with and in some cases considerably cheaper than current market prices for fishmeal.

According to the study, this process could profitably supply total global demand for fishmeal with methane captured in the U.S. alone.

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Stanford researchers reveal how to turn a global warming liability into a profitable food security solution

Photo, posted April 30, 2017, courtesy of Artur Rydzewski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Roads And Chimpanzees | Earth Wise

November 8, 2021 By EarthWise Leave a Comment

The chimpanzee is a species of great ape native to tropical regions of Central and West Africa. Chimpanzees are highly social animals and can live to be over 50 years old. In fact, chimpanzees are our closest cousins. We share about 98% of our genes with chimpanzees.

According to the African Wildlife Federation, it’s estimated that at most only 300,000 chimpanzees remain in the wild today. They face a myriad of challenges, including habitat degradation and hunting.

According to new research from the University of Exeter in the U.K., roads have a negative impact on chimpanzee populations that can extend for several miles. In the study, which was recently published in the journal Conservation Letters, the researchers analyzed the impact of major and minor roads on wild western chimpanzee numbers in the eight African countries in which they live. They found that negative impacts extended an average of 10.7 miles from major roads, and 3.4 miles from minor roads. The researchers found that the density of chimpanzee populations dropped steadily from the edges of these areas to the lowest value alongside the roads. Only 4.3% of the chimpanzees’ range remains unaffected by roads.

While the study did not investigate why roads affect chimpanzee numbers, the research team did offer some clues. In addition to noise and roadkill, roads provide access to unexploited areas for industries that often reduce or remove chimpanzee habitats. Roads can also restrict chimpanzee movements, and provide easier access for hunters.

The researchers hope their findings will bring about more effective guidelines to mitigate the impact of roads on wildlife.

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Roads have far-reaching impact on chimpanzees

Photo, posted August 12, 2014, courtesy of Rod Waddington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wild Pigs And The Environment | Earth Wise

September 3, 2021 By EarthWise Leave a Comment

There are millions of wild pigs in the world with the largest numbers in the United States and Australia but significant numbers in South America, Europe, and China. In the US, there are as many as 9 million feral swine living in 38 states. A conservative estimate indicates that they cause about $1.5 billion in property and agricultural damage each year in this country.

Researchers in Australia have studied the climate damage wild pigs are causing across five continents. According to the study, by uprooting carbon trapped in soil, wild pigs are releasing over 5 million tons of carbon dioxide annually, which is the equivalent of 1.1 million cars.

When soils are disturbed from humans plowing a field, or from wild animals uprooting, carbon is released into the atmosphere. According to the researchers, wild pigs are just like tractors plowing through fields, turning over soil to find food.

The study used predictive population models coupled with advanced mapping techniques to pinpoint the damage wild pigs are causing. According to the models, pigs are currently uprooting an area between 14,000 and 47,000 square miles, which is an enormous amount of land. The effects are not just on the health of the soil and on carbon emissions. This much damage also threatens biodiversity and food security.

Wild pigs are basically a human-caused problem, being either feral descendants of domestic swine, or hybrids of domestic swine and wild boars. Wild pigs are prolific and their numbers have been expanding rapidly Controlling their populations will require cooperation and collaboration across multiple jurisdictions.

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The climate impact of wild pigs greater than a million cars

Photo, posted July 1, 2017, courtesy of Shiva Shenoy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Tracking Endangered Species From Space | Earth Wise

March 4, 2021 By EarthWise Leave a Comment

Scientists at the University of Bath and the University of Oxford in the UK have developed a technique for remotely surveying elephants and other wildlife using satellite images and deep learning. The technique has the same accuracy as human counts done on the ground or from low-flying airplanes.

The new computer algorithm can analyze high-resolution satellite images and detect African elephants in both grasslands and forests. Previous techniques for monitoring wildlife from space were limited to homogenous habitats, such as the case of tracking whales in the open ocean.

On-the-ground or airplane surveys to monitor animal numbers are expensive and time-consuming. Satellites can collect nearly 2,000 square miles of imagery in a few minutes thereby eliminating the risk of double counting and reducing a process that previously took weeks to just a few days. The use of satellites also eliminates the logistical problems of monitoring species populations that cross international borders.

Accurate monitoring is important for efforts to save endangered species. There are only 40,000 – 50,000 African elephants left in the wild. It is essential to know where the animals are and how many there are in various locations. The new method is able to count elephants in mixed ecosystems, such as savannah and forests, where tree cover would previously have made satellite tracking difficult.

With satellite imagery resolution increasing every few years, it should be possible to see ever-smaller things in greater detail. The new algorithm works well for elephants; it may eventually become practical to track animals as small as an albatross from space.

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A New Way to Track Endangered Wildlife Populations from Space

Photo, posted March 15, 2008, courtesy of Michelle Gadd/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Search For Lingering Ash | Earth Wise

January 12, 2021 By EarthWise Leave a Comment

Ash trees are some of the most important plants along riverbanks and in wetlands. There are three ash species in North America: the white, green, and black ash. Unfortunately, all three species are critically endangered because of the emerald ash borer.

The emerald ash borer is an exotic beetle from Asia that first showed up in the U.S. in southeastern Michigan in the summer of 2002. The adult beetles do little damage but the larvae feed on the inner bark of ash trees and disrupt the tree’s ability to transport water and nutrients. The beetles are now found in 35 states and 5 Canadian provinces and have killed hundreds of millions of ash trees.

The greatest hope for preserving ash tree species relates to lingering ash, which are those rare trees that have managed to survive the onslaught of the emerald ash borer. The idea is that those trees have some natural genetic resistance to the borer. Getting seeds and cuttings from lingering ash and propagating them at nurseries may be the only way to get ash trees back into the natural landscape.

Lingering ash are extremely rare and therefore very hard to find. As a result, researchers are reaching out to the public to help with the search and report the presence of these surviving trees in woodlands.

Researchers want to find large, mature trees left among those that were killed by the invasive insect and therefore display great resilience. In Kentucky, university and Division of Forestry researchers are making use of software tools to engage the assistance of the public. An app called TreeSnap allows people to provide data on trees that they find in their community, on their property, or out in the wild.

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Researchers Ask Public for Help Finding Lingering Ash Trees

Help Our Nation’s Trees!

Photo, posted May 31, 2014, courtesy of Katja Schulz via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change and Komodo Dragons | Earth Wise

October 12, 2020 By EarthWise Leave a Comment

The Komodo dragon is the world’s largest and most iconic lizard. Growing up to 10 feet long and weighing up to 360 pounds, Komodo dragons are endemic to five islands in southeast Indonesia, four of which are part of Komodo National Park, as well as a fifth that has three nature reserves. Komodo dragons have existed on earth for at least four million years, and it’s estimated that 4,000 of them survive in the wild today.

But according to a new study by researchers from the University of Adelaide and Deakin University in Australia, Komodo dragons could soon be driven to extinction. The research team found that the impacts of both global warming and sea level rise are likely to cause a sharp decline in available habitat for Komodo dragons. Current conservation strategies are not enough to avoid climate-driven Komodo dragon population declines.

The study, which was recently published in the journal Ecology and Evolution, involved close collaboration with Komodo National Park and the Eastern Lesser Sunda Central Bureau for Conservation of Natural Resources.

Climate-change-informed decisions should be a common part of conservation practice. According to the research team’s conservation model, Komodo dragons on two of the five Indonesian islands are less vulnerable to climate change. But those two islands might not be enough for the survival of the species. Conservation managers may need to translocate Komodo dragons in the future – to sites where these animals have not been found for decades – in order to protect the species from extinction.

Without taking immediate action to mitigate climate change, the research team says many range-restricted species like Komodo dragons are at risk of extinction.

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Climate change threatens Komodo dragons

Photo, posted August 6, 2016, courtesy of Tony Alter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Shrinking Alaskan Salmon | Earth Wise

September 24, 2020 By EarthWise Leave a Comment

According to a new study published in the journal Nature Communications, salmon returning to Alaskan rivers have become significantly smaller over the past 60 years. As a result of climate change and competition from hatchery fish, wild salmon are spending less time at sea and are returning to spawning grounds at younger ages.

The study, by scientists at the University of Alaska at Fairbanks and the University of California Santa Cruz, examined measurements of over 12 million fish collected by the Alaska Department of Fish and Game from 1957 through 2018. Over that time period, four out of Alaska’s five wild salmon species – Chinook, chum, coho, and sockeye – have shrunk in size. Chinook salmon is the official state fish of Alaska and they used to stay out at sea for seven years before returning to spawn. Many are now returning to rivers at just four years old and are on average 8% smaller than they were 30 years ago.

The shrinking size of Alaskan salmon has consequences for people, the economy, and ecosystems in Alaska. Wild salmon is a staple food for many residents of the state, particularly among indigenous groups. More generally, Alaska produces nearly all of the wild salmon in the U.S. Commercial fishing of over 200 million wild salmon in 2019 resulted in $657 million in income. The fish are also an important food source for bears and other wildlife and the spawning migration of salmon plays an important role in nutrient transportation in Alaskan river ecosystems.

Multiple factors are driving the changes in the salmon population, but the largest effects are the changing climate and the abundance of salmon in the ocean due in part to hatchery production that results in competition for the salmon’s food.

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Alaska’s Salmon Are Significantly Smaller Than They Were 60 Years Ago

Photo, posted September 5, 2019, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recovering Condors | Earth Wise

August 12, 2020 By EarthWise Leave a Comment

The California condor is the largest North American land bird. Its wingspan is nearly 10 feet and its weight of up to 26 pounds nearly equals that of the trumpet swan, the heaviest native North American bird. California condors can live up to 60 years, making them among the world’s longest-living birds as well. But California condors became extinct in the wild in 1987.

Lead poisoning is the primary threat to condors. The birds are scavengers and feeding on the carcasses of dead animals that contain fragments of lead rifle ammunition is responsible for half of all condor deaths.

Condors historically occupied California’s Sierra Nevada mountains and were known to nest in the cavities of giant sequoia trees. By 1982, the wild population was reduced to just 22 birds, and all of those were eventually trapped and brought into captivity to prevent extinction of the species.

A captive breeding program was undertaken at the Los Angeles Zoo and the San Diego Wild Animal Park. With the success of that program, in 1992 the U.S. Fish and Wildlife Service began releasing condors back into the wild in the mountains of Los Padres National Forest in Southern California. That flock has grown to about 100 birds through both wild reproduction and additional release of captive-bred birds.

The Southern California flock continues to expand its range with birds in 8 California counties and even in Arizona, Utah, and Baja California in Mexico. The total wild population of condors is now estimated to be about 340 birds. Recently, condors have been spotted in Sequoia National Park, a part of its historic range where the birds have been absent for nearly 50 years.

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California Condors Spotted in Sequoia National Park, First Time in Nearly Half a Century

Photo, posted May 20, 2005, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Monitoring Wildlife For Warning Signs of the Next Pandemic | Earth Wise

July 29, 2020 By EarthWise Leave a Comment

According to the World Health Organization, the coronavirus that causes COVID-19 likely originated in wild bats near Wuhan, China, and may have been passed to a second animal species before infecting people. Since then, according to data from Johns Hopkins University, more than 13 million people around the world have been infected by COVID-19 and about 600,000 have died.

But despite the ever-present threat of a new virus sparking the next pandemic, there is currently no global system to screen for viruses in wild animals that could eventually spill over to humans.

In an article recently published in the journal Science, a group of scientists is calling for the creation of a decentralized global system of wildlife surveillance. The establishment of this global system could help identify viruses in wild animals that have the potential to infect and sicken people before another global disease outbreak begins.

According to the scientists, coronaviruses alone have caused outbreaks in humans three times in the last 20 years: SARS (or Severe Acute Respiratory Syndrome), MERS (or Middle East Respiratory Syndrome), and COVID-19.

While it’s impossible to know today how often viruses jump from animals to humans, human activity is making such spillover events more and more likely. For instance, many continue to develop wild animal habitat to build new homes or businesses. Some catch wild animals and re-sell them either for consumption or as exotic pets. Parts from these wild animals are often shipped around the world as trinkets or as ingredients for traditional medicines.

A global system that could identify potentially harmful viruses before they jump to humans is technologically feasible, affordable, and clearly necessary.

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COVID-19 Dashboard by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU)

Global wildlife surveillance could provide early warning for next pandemic

Photo, posted January 15, 2008, courtesy of Doug Beckers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Birdseed And Weeds | Earth Wise

April 16, 2020 By EarthWise Leave a Comment

More than 55 million adult Americans feed wild birds and along the way spend more than three billion dollars a year on bird food as well as nearly a billion on bird feeders, bird baths, bird houses and other bird feeding accessories. Feeding birds is a very popular hobby in both the United States and the United Kingdom.

Researchers at the University of Missouri in Columbia Missouri investigated the content of 98 commercially available bird feed mixes. They uncovered several significant things.

The various mixes contained seeds from 29 weed species and almost all of the mixes contained seeds for pigweed, which can be a significant threat to agriculture. One in ten of the mixes contained Palmer amaranth or waterhemp seeds that demonstrated a resistance to glyphosphate. Other common weed species found in many of the mixes were kochia, common ragweed, foxtail species, and wild buckweed.

The overall collection of seed mixes contained an average of 363 amaranthus seeds in each kilogram of bird feed. Based on this, it is possible that 105 million amaranthus seeds are transported in bird feed mixes each year.

According to the researchers, it is difficult to estimate the exact role that commercial bird seed plays in spreading troublesome weed species into new regions, but it is clear that the widespread use of these seed mixes is a contributing factor to the spread of weeds.

The researchers recommend careful weed management in crop fields designated for bird feed, as well as sieving during packaging to reduce weed seed contamination. They also noted that regulatory measures adopted in Europe to limit weed seed content in bird seed have proven to be effective.

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Examination of commercially available bird feed for weed seed contaminants

Photo, posted August 18, 2013, courtesy of Emma Craig via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Exotic Pets Can Become Problems

August 26, 2019 By EarthWise Leave a Comment

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.

Bees And Plastic

July 17, 2019 By EarthWise Leave a Comment

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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