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Global Decline In Wildlife | Earth Wise

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According to a new report released by the World Wildlife Fund, global populations of mammals, birds, amphibians, reptiles, and fish have declined by 68% in less than half a century. 

The report presents a comprehensive overview of the state of the natural world based on the tracking of almost 21,000 populations of more than 4,000 vertebrate species between 1970 and 2016. 

The report shows that the main cause of the dramatic decline in species populations on land is habitat loss and degradation, which includes deforestation driven by food production.  Additional factors include land-use change and the use and trade of wildlife.

Wildlife populations found in freshwater habitats have suffered a decline of 84%, which is the steepest decline in any biome.

Insect populations have declined rapidly in many places, but most of the information about insects comes from a small number of countries in the northern hemisphere.  There is very little information from large parts of the world, such as Africa, South America, and Asia, where land-use change and agricultural expansion are happening fast.  What happens to insects matters a lot to humanity.  Insects play central roles in the world’s ecosystems as waste processors, pollinators, predators, and prey. 

The report is clear evidence of the damage human activity is doing to the natural world.  Threats to the integrity of ecosystems endanger humans and all of nature.  This is especially apparent in the midst of a global pandemic.  It is now more important than ever to take coordinated global action to halt and reverse the loss of biodiversity and wildlife populations across the globe.

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Living Planet Report reveals 68% decline in global wildlife populations since 1970

Photo, posted May 7, 2020, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The United States And Ticks | Earth Wise

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

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

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

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

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

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

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Tick surveillance and control lagging in US

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

Earth Wise is a production of WAMC Northeast Public Radio.

Moving Up And Away | Earth Wise

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A new study by the Wildlife Conservation Society, the US Forest Service, and UC Berkeley has shown that mountain-dwelling species trying to escape warming temperatures may also be finding refuge from human pressure.

The study shows that nearly 60% of the world’s mountainous areas are under intense human pressure.  Most of that pressure occurs at lower elevations and mountain bases, where more people live, grow food, and build roads.  The researchers used climate models to predict how various species would move as the climate changes.   Based upon these predictions, they found that species tend to move to higher elevations, where temperatures are lower.  But those elevations also have more intact land for species because there is less human activity.

Mountains are home to over 85% of the world’s amphibians, birds, and mammals and these species are at risk from human activities such as agriculture, livestock grazing, and development.  These things reduce their habitats, but meanwhile the warming climate pushes them upslope as they struggle to find tolerable temperatures.

The researchers point to their study as new guidance for conservation efforts.  They warn that many conservation efforts don’t take into account the effects of human pressure.   Factoring in human pressure reveals the true extent of mountainous areas for species that are restricted to intact landscapes.  These are often the species that are of greatest concern to conservationists.  This true shape refers to how much land area is potentially available as habitat for a species as it moves up in elevation.  

The results offer a glimmer of hope for mountain-based species under climate change as they move away from the most intense human activity.

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Climate change may push some species to higher elevations — and out of harm’s way

Photo, posted November 22, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

What Is An Endangered Species? | Earth Wise

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Biodiversity is declining rapidly throughout the world and people are mostly the reason.  Species are disappearing because of changes in land and sea use, the direct exploitation of organisms, climate change, pollution, and invasive alien species resulting from globalization.  The challenges of conserving the world’s species are many and difficult.  Among these challenges are determining which species are endangered and how and when to protect them.

What constitutes an endangered species is not necessarily obvious. 

Extinction risk increases as a species is driven to extinction from portions of its natural range.  Most mammal species have already been driven to extinction from half or more of their historic ranges because of human activities.

According to a recent survey of ordinary Americans, three-quarters of participants said that a species deserves special protections if it had been driven to extinction from any more than 30% of its historic range.  This compares with the language of the U.S. Endangered Species Act that defines an endangered species as one that is “in danger of extinction throughout all or a significant portion of its range.”

Experts and decision-makers are more accepting of risks and losses because they believe greater protection would be impossibly expensive.  Decision-makers tend to be influenced by special interest groups with a vested interest in not instituting protections.

Before human activities began elevating extinction risk, a typical vertebrate species would have experienced an extinction risk of 1% over a 10,000-year period.  Current policies consider a 5% risk over 100 years to be acceptable.  Policies consider whether we can afford to protect species.  Given the dangers of declining biodiversity, we should ask whether we can afford not to.

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What Is An Endangered Species?

Photo, posted July 29, 2018, courtesy of Sergio Boscaino via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Decline Of Earth’s Largest Freshwater Creatures

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While nearly 70% of the globe is covered by water, only 2.5% of it is freshwater.  The rest is saline and ocean-based.  And only 1% of our freshwater is easily accessible, with much of it locked away in snowfields and glaciers.  

Despite freshwater only making up a small fraction of all water on the planet, it’s home to one third of all vertebrate species.  Some have survived hundreds of millions of years, but many of the world’s largest freshwater creatures – including fish, reptiles, amphibians, and mammals – may soon find themselves on the brink of extinction.

According to a study recently published in the journal Global Change Biology, scientists from the Leibniz-Institute of Freshwater Ecology and Inland Fisheries and international colleagues have quantified the global decline of freshwater megafauna for the first time.  In four decades since 1970, the global populations of these freshwater giants have declined 88% – twice as much as the loss of vertebrate populations on land or in the oceans. 

Freshwater megafauna include all freshwater animals that weigh 30 kilograms (about 66 pounds) or more, such as certain dolphins, beavers, crocodiles, turtles and sturgeons.

Overexploitation is one of the main threats to freshwater megafauna.  (These animals are often targeted for their meat, eggs, and skin).  The other main threat is the loss of free-flowing rivers. Many of the world’s large rivers are already highly fragmented, which impacts access to spawning and feeding grounds.  The research team says another 3700 large dams are planned or under construction, including 800 in habitats rich with freshwater megafauna, including the Amazon, Congo, and Ganges river basins.

Current conservation measures are clearly failing our freshwater creatures. 

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88 percent decline of big freshwater animals

Earth’s largest freshwater creatures at risk of extinction

Photo, posted March 25, 2012, courtesy of the U.S. Fish and Wildlife Service 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.

The Future Of Animals

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Researchers at the University of Southampton have forecast a global shift towards smaller birds and mammals over the next century.   

According to the research team, small, fast-lived, highly fertile, and insect-eating animals, which can thrive in all sorts of habitats, will predominate in the future.  Rodents and songbirds are examples of the so-called ‘winners.’  Less adaptable, slow-lived species, requiring specialist habitats, will be more likely to face extinction.  Among the so-called ‘losers’ are the black rhino and the tawny eagle. 

The researchers focused on more than 15,000 living mammals and birds and considered the following five characteristics: body mass, breadth of habitat, diet, litter or clutch size, and length of time between generations.  Using this data and data from the IUCN’s Red List of Threatened Species, the researchers used modern statistical tools to project and evaluate the loss of biodiversity.  

The study, which was recently published in the journal Nature Communications, predicts that the average body mass of mammals will collectively decline by 25% over just the next 100 years.  Over the past 130,000 years, the average body size of mammals only declined 14%.

This substantial downsizing of animals is forecasted to occur due to the effects of ecological change. But, according to the study’s lead author, the loss of these species, which perform unique functions within the global ecosystem, may ironically wind up being a driver of change as well.       

The researchers hope future studies will further explore the long-term effects of species extinction on habitats and ecosystems. 

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Study predicts shift to smaller animals over next century

Photo, posted April 6, 2013, courtesy of Nic Trott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Humans And Vertebrate Mortality

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According to a new study, more than one-quarter of the planet’s land vertebrates die because of humans.  This is a “disproportionately huge effect” on the other land vertebrates that share planet’s surface with us. 

Researchers from the SUNY College of Environmental Science and Forestry and the U.S. Department of Agriculture reviewed 1,114 published studies in which nearly 43,000 animals had perished.  Their study, which was recently published in the journal Global Ecology and Biogeography, found that 28% of the animals’ deaths were directly attributable to humans.  The other 72% died from natural sources.  

Mammals, birds, reptiles, and amphibians that died between 1970 and 2018 in the Americas, Asia, Africa, Europe, and Oceania were the foundation of the study.  All of these vertebrates had been either collared or tagged as part of other research projects. 

The researchers point out that humans are only one among more than 35,000 species of terrestrial vertebrates globally.  The fact that humans are responsible for more than one-quarter of their deaths illustrates the profound magnitude of the problem.  And that statistic is just the direct causes.  According to the researchers, when urban growth and other land use changes that erode habitat are considered, the human impact is likely even greater. 

The study found that the impact of humans across all the different species was not equal. In fact, larger animals were more likely to be killed by humans than smaller animals. Adult animals were more likely to be killed by humans than juveniles. 

The researchers conclude that humans are such a major contributor to terrestrial vertebrate mortality that they could potentially impact both evolutionary processes and ecosystem functioning. 

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On the land, one-quarter of vertebrates die because of humans

Photo, posted March 6, 2019, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Japan And Whaling

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The commercial hunting of whales nearly drove the giant mammals to extinction.  By the 1960s, as hunting technologies improved and ships began to resemble floating factories, it became clear that whaling could not continue unchecked. 

But despite all this, commercial whaling was never actually banned.  Instead, in 1986, members of the International Whaling Committee (IWC) agreed to a whaling moratorium in order to allow whale stocks to recover.  Pro-whaling nations like Japan, Iceland, and Norway expected the moratorium to be temporary until the whales stocks recovered, and a consensus on catch quotas could be established.  But the temporary moratorium became a quasi-permanent ban, much to the delight of conservationists and to the dismay of whaling nations. 

As a result, Japan recently announced it is leaving the international agreement and plans to resume commercial whaling.  The agreement though never really stopped Japanese whaling in the first place, because it allowed the country to kill whales for scientific research.  Japan has had an annual Antarctic catch quota of 333 minke whales, producing notoriously little in terms of whale science while producing  lots of whale meat.  As part of its withdrawal from the IWC, Japan will cease its Antarctic hunts and limit whalers to its own waters.  Commercial Japanese whaling will resume in July. 

Once popular in Japan, whale meat consumption has plummeted, falling 98% between 1962 and 2016. The industry employs fewer than 1,000 people and is dependent on government subsidies. 

Many governments and conservationist groups condemned Japan’s withdrawal, declaring the move out of step with the international community.  They argue that, rather than hunting whales, urgent action is needed to conserve marine ecosystems. 

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Japan to Resume Commercial Whaling, Defying International Ban

Photo, posted February 5, 2009, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mammals Can’t Seem To Evolve Fast Enough

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Our planet has been through five upheavals over the past 450 million years.  During each one, the environment on earth changed so dramatically that most plant and animal species became extinct.  After each of these mass extinction events, evolution slowly filled the gaps in the environment with new species. 

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Corals Like Plastic

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Microplastics, which are tiny pieces of weathered plastic less than 5 millimeters in diameter, have been accumulating in the oceans for the past 40 years and are now ubiquitous in the marine environment.  They are a major threat to many kinds of marine life, including numerous species of birds, turtles, fish, marine mammals and invertebrates who ingest the stuff causing a variety of problems.

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Changing National Parks

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America’s National Parks are special places of incomparable beauty and fascination.  When the National Park Service was first created 100 years ago, it was instructed to leave these places “unimpaired for the enjoyment of future generations.”   We now live in a time when the changing climate is altering many aspects of the landscape including in many national parks.  The parks are protected, but they are changing.

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Mapping Emerging Infectious Diseases

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Ebola. Hantavirus. Lyme disease. What do they have in common? Like most emerging infectious diseases, they originated in mammals. So many debilitating pathogens make the jump from wildlife and livestock to humans, yet at the global scale little is known about where people are most at risk of outbreaks.

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