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Almost a dire wolf

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Researchers around the world are working on what some call the ‘de-extinction’ of iconic animals of the past such as the wooly mammoth, the dodo, and the Tasmanian tiger.  The idea is to decipher the genome from DNA of preserved specimens and, using the tools of modern genetic engineering and cloning technology, alter the DNA of closely related modern species to recreate the extinct species.

A company called Colossal Biosciences recently announced that it has brought back the dire wolf, a species that has been extinct for 10,000 years.  Dire wolves have white coats and are larger than modern wolves, have more powerful shoulders, a wider head, and larger teeth and jaws.  Colossal is now raising three wolves they have engineered at a 2,000-acre site at an undisclosed location.

 The wolves were created by taking the DNA of modern grey wolves and editing 14 genes substituting ones from ancient dire wolf specimens.  Wolves have about 19,000 genes, so the changes from the grey wolf genome are very minor but enough to produce an animal that looks just like a dire wolf.  But is it a dire wolf?

It really isn’t.  Ancient DNA is always greatly damaged.  Only parts of it survive.  We don’t actually have the complete genome of the dire wolf.  What we have is bits and pieces that, thanks to modern technology, allow us to produce a phenotype of a dire wolf; that is, an animal with the same observable features. 

Whether this accomplishment is a worthwhile and appropriate thing to do is a question that continues to be debated.

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The Return of the Dire Wolf

Photo courtesy of Colossal Laboratories & Biosciences.

Earth Wise is a production of WAMC Northeast Public Radio

Tigers in India

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The Anthropocene is the term that describes the current era in Earth’s history when human activities are having a significant impact on the planet.  It is an epoch filled with species extinction and species attrition in both numbers and range.  The population of large carnivores are among the most affected species and recovering these animals that play important roles in ecosystems is a formidable challenge.

Tigers in Asia are a prime example of extirpation – removal of a species from a specific area.  They have been eliminated in more than 90% of their historic Asian range over the past century.  A new study, published in Science has found that tigers in India are making a comeback.

India’s National Tiger Conservation Authority estimates that between 2010 and 2022, India’s tiger population grew from 1,706 to 3,682.  Tigers are thriving not only on protected lands but also near some human communities.

Tigers are gone from poorer areas where poaching was prevalent and from areas affected by the violent conflict associated with India’s Maoist rebellion.  On the other hand, the big cats can be found near some prosperous communities where poaching is rare.  Farmers keep cattle in enclosures to protect them from tigers.  

The success in protecting tigers in India could provide some insights for Europe where wolves are making a comeback, and perhaps even in the American West where the resurgence of wolf populations is triggering a violent backlash.

Large predators can survive in the modern world with creative thinking and willingness to find a balance between protection and coexistence.

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India Doubled its Tiger Population in a Little More Than a Decade

Photo, posted January 8, 2014, courtesy of Roderick Eime via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sharks and rays in a warming world

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Sharks and rays belong to a group of cartilaginous fish called elasmobranchs, which have been swimming in the world’s oceans for 450 million years. The resilient species have survived five mass extinction events, and are older than dinosaurs, trees, and Mount Everest. 

But despite their resilience, many species of sharks and rays today are threatened by human activities, including overfishing, habitat loss, and climate change.  In fact, according to a new study led by researchers from the University of Vienna in Austria, more than one third of the shark and ray species known today are severely under threat. 

The study, which was recently published in the journal Biology, found that higher carbon dioxide levels were having a negative effect on sharks and rays, ranging from impacts on the animals’ senses to changes in the skeleton during embryonic development.  An examination of fossil records found that higher CO2 levels had contributed to the extinction of individual shark and ray species in the past. 

But the study also found that global warming could be creating opportunities for sharks and rays.  Rising sea levels and higher temperatures have historically expanded shallow coastal habitats and warm waters, supporting species biodiversity.

But according to the research team, the rapid environmental changes, combined with the impacts from human activities, outpace the ability of sharks and rays to adapt, making it unlikely that they will benefit from global warming.

Protecting sharks and rays is crucial not only for their survival but also for maintaining entire ocean ecosystems. Without top predators, these ecosystems could collapse, impacting both marine life and the people and industries that depend on it.

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Sharks and rays benefit from global warming – but not from CO2 in the Oceans

Myths About Sharks and Rays

Photo, posted November 27, 2007, courtesy of Laszlo Ilyes via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Corals and climate change

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Climate change is a major threat to coral reefs around the world.  Ocean warming triggers coral bleaching – a stress response where corals expel the symbiotic algae essential for their survival.  If coral bleaching is severe, it can lead to coral death.

A new study led by scientists from Newcastle University in England suggests that corals are unlikely to adapt to ocean warming quickly enough to keep pace with global warming, unless there are rapid reductions in global greenhouse gas emissions.

The study, which was recently published in the journal Science, found that coral heat tolerance adaptation via natural selection could keep pace with ocean warming, but only if the climate goals of the Paris Agreement are realized.  In the Paris Agreement, countries agreed to limit global warming by the end of the century to two degrees Celsius above pre-industrial levels.  

However, current climate policies around the world have the globe on track to warm by three degrees Celsius.  According to the research team, this could lead to significant reductions in reef health, elevated risks of local coral extinctions, and considerable uncertainty in the so-called “evolvability” of corals. 

Coral reefs are among the most biologically diverse ecosystems on Earth.  They are often referred to as the “rainforests of the sea” because they support an incredible variety of marine life.  They provide essential ecosystem services, such as protecting coastlines from erosion and storm surges, supporting fisheries, and serving as a source of income through tourism. Coral reef health is vital for the health of the planet.

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Coral adaptation unlikely to keep pace with global warming

Photo, posted June 9, 2012, courtesy of Bokissa Private Island Resort via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Averting a mass extinction

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There has been widespread concern that biodiversity is under siege and that we are in the beginnings of a sixth mass extinction in the long history of the Earth, this time caused by the actions of humanity.  There has been considerable debate about what can be done about it and solutions generally involve protecting large areas of the planet from human disruptions.  Some countries have set a target of protecting 30% of land and sea.

A new study by a broad coalition of conservation organizations and published in Frontiers in Science, concludes that humans can preserve much of the great diversity of life on Earth by setting aside just 1.2% of the planet for protection.

The experts mapped the wilderness available to rare and threatened plants and animals.  They then identified specific hotspots for rare wildlife that have yet to be protected.  They found a total of 16,825 such sites which nevertheless all together add up an area smaller than the state of Wisconsin.

Some scientists have been warning that by focusing too much on the size of protected lands, we are not necessarily safeguarding areas that are especially rich in wildlife.  The new study pushes for prioritizing hotspots for rare species, which the authors claim would be sufficient to stave off a sixth mass extinction.  The truth is that most species on Earth are rare, meaning that they are few in number or cover a small range, or both.

The study estimated that the cost of protecting the identified hotspot sites would be $263 billion, which is certainly a large amount of money.  But the authors point out that this sum to save global biodiversity is less than the yearly revenue of Shell Oil.

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To Avert a Mass Extinction, Protect 1 Percent of Earth

Photo, posted April 20, 2018, courtesy of Per Harald Olsen / AfricanBioServices via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Otters to the rescue

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California sea otters were hunted almost to extinction in the 19th century.  Only a small number survived along California’s central coast.  But over time, the otters recovered and increasingly recolonized their former habitats.

Sea otters are playing an important role in safeguarding California’s kelp forests and marshlands against the harmful effects of climate change.

Over much of the 20th century, increasing ocean heat had devastated underwater kelp forests by driving a population explosion of sea urchins that devour kelp.  But sea otters eat urchins and as the sea otter population has grown, kelp has flourished.  According to a new study published in PLOS Climate, the underwater kelp canopy along the central coast increased by 56% since 2016.  Kelp forests have become more extensive and resilient to climate change wherever sea otters have reoccupied the California coastline.

At the same time, sea otters started recolonizing their former habitat in a central California estuary several decades ago and erosion has slowed by as much as 90%.  The main reason is that otters love to eat the marsh crabs that were devouring the plants in this coastal ecosystem.  The marsh plants establish dense root systems that can withstand waves and flooding.  It would cost millions of dollars for humans to rebuild creekbanks and restore these coastal marshes.  Instead, sea otters have been stabilizing them for free in exchange for a crab feast.

Sea otters are playful creatures that people enjoy watching.  It turns out that they are also very valuable ecosystem engineers that are helping to mitigate the effects of the warming climate.

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How Sea Otters Are Protecting the California Coast Against Climate Change

Photo, posted May 17, 2021, courtesy of Michael L. Baird via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Why are bees making less honey?

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Scientists have been sounding the alarm on the global struggle of pollinators for a long time.  According to the United Nations, nearly 35% of the invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since 75% of the world’s food crops depend on pollination to some extent, the decline of pollinators poses a major threat to global food security.

Honey bees are among the struggling pollinators.  Honey bee colonies in the United States have experienced annual population declines since 2006.  But in addition to there being fewer bees, the bees that remain are also making less honey.  In fact, honey yields in the United States have been declining since the 1990s. 

A new study by researchers from Penn State University has solved some of the mystery.  Using five decades of data across the United States, the research team analyzed the factors that could be affecting the number of flowers growing in different regions, which, in turn, affects the amount of honey produced by bees. 

In the study, which was recently published in the journal Environmental Research, the scientists found that climate conditions and soil productivity were two of the biggest factors in estimating honey yields.  States in both warm and cool regions produced higher honey yields when they had productive soils.  These two factors set a baseline production level of honey, while herbicide use, weather, and land use changes influenced how much honey was produced in a given year. 

The study’s findings  provide valuable insights that should help beekeepers, growers, and land managers better support honey bees.

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Why are bees making less honey? Study reveals clues in five decades of data

Photo, posted August 30, 2021, courtesy of Brandon O’Connor / NRCS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Thousands of species threatened

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The International Union for the Conservation of Nature is an organization working in the field of nature conservation and sustainable use of natural resources.  The IUCN has been around for nearly 75 years and is the global authority on the status of the natural world and the measures needed to safeguard it.

In its latest accounting, the IUCN has determined that more than 44,000 species worldwide are threatened with extinction.  Among them, nearly 7,000 face an immediate threat from climate change.

The organization tracks 157,000 species to compile its Red List and found that climate change poses a growing threat to many kinds of wildlife. At particular risk are freshwater fish including Atlantic salmon, which are now classified as “Near Threatened.” 

In all, about 25% of freshwater fish are threatened with extinction.  This is in part driven by rising sea levels which causes saltwater to be driven up into rivers.  Some 41% of amphibians are threatened with extinction, in part due to more intense heat and drought.  Many populations of green turtles are at risk of extinction because of rising temperatures lowering hatch rates and rising sea levels flooding nests.

It isn’t just animals at risk.  For example, big leaf mahogany, one of the world’s most commercially sought-after timber trees, has moved from Vulnerable to Endangered on IUCN’s Red List.  Thousands of trees have been added to the Red List, many of which are timber species, and some are keystone species in forests.

Endangered and threatened species are often irreplaceable parts of ecosystems which provide humans with many services that only the natural world can.

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More Than 44,000 Species Now Threatened With Extinction

Photo, posted November 22, 2010, courtesy of E. Peter Steenstra/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wildlife rebounding in Uganda

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The numbers of elephants, rhinos, and other animals in Uganda’s nature preserves is steadily improving, reversing the trend of steady declines previously caused by poachers, wildlife traffickers, and conflict.

Between the 1960s and 1980s, political conflict and lawlessness in Uganda led to massive declines in some species as poaching, trafficking, and encroachment ran rampant.

Uganda’s population of over 700 northern white and eastern black rhinos was completely wiped out in the early 1980s by people hunting them for their horns.  A charity brought four rhinos in 2005 to a sanctuary called the Ziwa Rhino and Wildlife Ranch and, according to the Uganda Wildlife Authority, there are now 33 in the facility.

Increased conservation efforts have allowed the population of buffalos to increase 77% to over 44,000 since 1983.  The number of elephants has surged almost 300% to nearly 8,000 over that same time period.  There has also been an increase in the number of mountain gorillas in dense forests.

Over the years, the Ugandan government has brought in a string of conservation policies including lengthy jail terms for violations.  As a result, wildlife populations have been on a steady recovery.

It is typical to think about species in terms of how close to extinction they are, but the ultimate goal of conservation is to recover species.  This means not only gaining distance from extinction but also resuming a species’ role in its ecosystem and repopulating its former range.  Whether the wildlife in Uganda is achieving this status remains to be seen, but the trends are very positive.

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Uganda Sees Resurgence of Rhinos, Elephants, Buffaloes

Photo, posted September 15, 2014, courtesy of Rod Waddington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Spooky Reality | Earth Wise

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According to the National Retail Federation, American consumers will spend a whopping $12.2 billion on Halloween this year, exceeding last year’s record of $10.6 billion.  A record number of people – 73% of Americans – will also participate in Halloween-related activities this year, up from 69% in 2022.  But it’s not just our wallets that take a beating. 

Halloween generates a frightening amount of waste.  Picture all those flimsy and often single-use costumes, polyester cobwebs, plastic-wrapped candy, mass-produced decorations, and so forth. Scary stuff!  Here are some simple tricks to make the holiday more sustainable this year. 

Invest in quality costumes.  Those mass-produced costumes leave the largest carbon footprint from Halloween.  They are often made from non-recyclable plastic and most end up in landfills by mid-November.   By renting, thrifting, swapping, or making your own costumes, many of the negative impacts of dressing up for the holiday can be avoided.

Find environmentally-friendly decorations and supplies.  For example, carve local pumpkins and either save the seeds and flesh to eat later, compost it, or feed it to animals.  Make your own spooky decorations.  If you do buy decorations, ensure that they are durable and reusable.  And use wicker baskets, old bags, or pillowcases when trick-or-treating.

Finally, purchase organic and fair trade candy if you’re able to do so.  Some of the largest candy manufacturers are major drivers of deforestation and species extinction around the globe due to their demand for sugar, palm oil, and cocoa beans.

Together, we can “green” Halloween.  

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Halloween Data Center

Photo, posted November 13, 2019, courtesy of Christian Collins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Aphids And Monarchs | Earth Wise

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Last year, the monarch butterfly was officially designated as endangered by the International Union for Conservation of Nature.  Estimates are that the overall population of the species has dropped between 20% and 90% over the past several decades. 

The migratory western population of monarchs is at the greatest risk of extinction, having declined by as much as 99.9% between the 1980s and 2021.  Legal and illegal logging and deforestation to make space for agriculture and urban development has destroyed much of the butterflies’ winter shelter in Mexico and California and pesticides and herbicides throughout the butterflies’ range kills both the butterflies and the milkweed that their larvae feed on.

A new study by the University of Florida has found that aphids feeding on the milkweed that grows across the southern portions of the US causes the butterflies to lay fewer eggs on the plants and the caterpillars developing on those plants were slower to mature.  The study showed that monarch laid three times as many eggs on aphid-free plants as they did on aphid-infested plants.

For years, there have been efforts to plant milkweed in urban areas to support monarch populations.  However, aphids and other insect pests often reach high densities on plants in urban settings. 

The researchers are advising home gardeners in the southern U.S. who want to conserve monarch butterflies to make use of safe techniques to limit aphid populations such as insecticidal soap.  This may not always be an option and the researchers are investigating other options to keep aphids at low levels that aren’t harmful to monarchs.

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Aphids make tropical milkweed less inviting to monarch butterflies, study finds

Photo, posted October 12, 2018, courtesy of Renee Grayson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cryo Conservation | Earth Wise

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Recent studies have shown that there has been a 69% decline in global animal populations since 1970.  There is a biodiversity crisis in the world.  In the face of this situation, there is a growing interest in using cold storage to preserve genetic samples taken from animals threatened with extinction.

Just as egg-freezing is used to preserve human fertility for a later date, the cryogenic freezing of genetic material from animals could be important in reducing species extinctions.  Living cell banks – also known as cryobanks – could preserve genetic materials from animals that include skin cells, embryos, semen, and live tissues.  These materials could be cultured and used for various applications including DNA extraction, assisted reproduction, ensuring genetic diversity in animal populations, and potentially reintroducing species back into their natural habitats.

There is a facility called the Frozen Zoo at the San Diego Wildlife Alliance which has genetic material from 965 different species, including 5% of the vertebrates currently listed as threatened on the IUCN Red List.  Further sampling from zoos and aquariums could increase that representation to almost 17%.

Genetic samples of 50% of the species currently listed as extinct in the wild are already represented in the Frozen Zoo.  Further sampling from the zoological community could increase this number to 91%.  This could provide a critical lifeline for these species that are on the brink of extinction.  As wildlife populations continue to decline around the world, it is more critical than ever to collect and preserve genetic samples from threatened species.

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Cryo conservation – a cool solution to saving species from extinction

Photo, posted September 30, 2018, courtesy of Andy Morffew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Shrinking Birds | Earth Wise

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A new study by researchers at Yale University looks at the way bird morphology is changing in response to the warming climate.  As temperatures rise, birds’ bodies are growing smaller, but their wings are growing longer.

In the study, published in the Proceedings of the National Academy of Sciences, the scientists analyzed two independently collected datasets containing 40 years of morphology changes in 129 bird species comprising 52 migratory species in North America and 77 South American species.

In both datasets, similar changes were observed over the 40-year period.  The overall trend makes sense given that being smaller and having longer wings both would help birds to stay cool in warmer weather.  What was less obvious was that the changes to the birds were much greater among the smallest bird species.

One possible explanation is that smaller species tend to reproduce on a shorter time scale and therefore evolve more quickly.  However, the study found no link between generation length and the changes in body size.

Another possible explanation is that smaller species tend to have larger populations, which means there is a greater chance of having individuals with desirable new traits that can get passed on.  But the scientists found no link between population size and shifts in body size either.

At this point, it is unclear why smaller birds are shrinking more.  More research is needed to figure out why larger birds are slower to adapt to climate change.  In general, larger species of animals have an increased risk of extinction.  This new research suggests that larger body size exacerbates extinction risk by limiting the ability for birds to adapt to the changes we are making to the climate.

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Birds Are Shrinking as the Climate Warms — and Small Birds Are Shrinking Faster

Photo, posted October 30, 2018, courtesy of N. Lewis / National Park Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Insects On The Menu | Earth Wise

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According to the World Food Programme, a record 349 million people across 79 countries are facing acute food insecurity.  This constitutes a staggering rise of 200 million people compared to pre-pandemic levels.  Nearly one million people globally are fighting to survive in famine-like conditions, which is ten times more people than just five years ago.  

As a result, many experts contend that alternative or so-called novel food sources – such as lab-grown meats, seaweed aquaculture, and insects – will be necessary to help fight global hunger and global food insecurity. 

Insects already form a significant part of diets in many cultures around the world.  Insects are great sources of nutrients, including protein, vitamins, and minerals.  But insects have yet to be embraced in any substantial way in western cultures… but that may be changing. 

In fact, the European Union has now certified four types of bugs as food fit for human consumption.  The larvae of lesser mealworms and house crickets recently became the third and fourth insects approved for sale as food in the EU, joining yellow mealworms and grasshoppers. Eight more applications are awaiting approval.

Insects are already a delicacy in many high-end restaurants around the world, and a normal and healthy part of diets in countries like Mexico and Thailand.  Embracing insects as a food of the future will not only help in the fight against global hunger, but will also help to reduce greenhouse gas emissions and to slow species extinction. 

In Western food markets, the so-called “yuck factor” remains the biggest hurdle to cross.  But as the world population grows, the need for sustainable solutions in the food industry grows with it. 

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Insects on the menu as EU approves two for human consumption

World Hunger Surged in 2020, U.N. Says

A global food crisis

Photo, posted April, 2014, courtesy of Shankar S. via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Assessing The Planet’s Most Unique Birds | Earth Wise

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Birds come in a huge variety of shapes, sizes and plumages.  The physical attributes of birds are adaptations that have taken countless millennia to develop, and physical attributes are closely related to the roles birds play in their environment.   

According to a new study led by researchers from the University College London in the U.K., bird species with extreme or uncommon combinations of traits have the highest risk of extinction.  Losing these bird species and the unique roles they play in the environment, including seed dispersal, pollination and predation, could have severe consequences on the health of ecosystems.

In the study, which was recently published in the British Ecological Society journal Functional Ecology, the researchers analyzed the extinction risk and physical attributes of 99% of all living bird species.  The research team used a dataset of measurements collected from living birds and museum specimens.  The measurements included things like beak size and shape, and the length of wings, tails and legs.  The researchers combined this data with extinction risk, and then ran simulations to see what would happen if the most threatened birds were to go extinct.

Some of the bird species that are both most unique and most threatened include the Christmas Frigatebird and the Bristle-thighed Curlew.  Kiwis were excluded from the study because the researchers viewed them as extreme morphological outliers.

While most unique birds were also classified as threatened on the Red List, the research was unable to show what links uniqueness in birds to extinction risk

The research team warns that if more isn’t done to protect these threatened species and avoid extinctions, the functioning of ecosystems will be dramatically disrupted.

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Planet’s most unique birds at higher risk of extinction

Photo, posted June 25, 2012, courtesy of Kristine Sowl / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Sumatran Rhino | Earth Wise

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The Sumatran rhinoceros is the smallest and most ancient rhino species and is the only surviving species with hair.  It is critically endangered.  Because of poaching and habitat destruction, there are fewer than 50 of them left in the wild and those are scattered in the rainforests of Sumatra and the Indonesian part of Borneo.  Mating encounters between surviving males and females are increasingly rare.

The last male Sumatran rhino in Malaysia died in 2019 but cell samples from that individual are the basis of an ambitious effort in bioengineering.

Researchers from the Max Delbruck Center in Germany are taking skin cells from the deceased rhino and turning them into stem cells.  The hope is to use these stem cells to derive egg and sperm cells to be the basis of assisted reproduction.  Fertilization would take place in a petri dish.  The resultant embryos would then be carried to term by surrogate rhino mothers.

The researchers have reported success generating induced pluripotent stem cells or IPS cells from the rhino skin samples.  IPS cells are able to divide indefinitely and can transform into any cell type in the body.

The next step is to try to cultivate primordial germ cells – the precursors of eggs and sperm.

This work is going on because it is increasingly difficult to preserve the Sumatran rhino population by gathering together remaining individuals in wildlife Reserves.  Females that have not been pregnant for a long time often become infertile because of cyst growth on their reproductive organs, and some are just too old to bear young.

It may take extraordinary efforts like these to save these animals from extinction.

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A second chance for the Sumatran rhino

Photo, posted April 30, 2008, courtesy of Willem V. Strien via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Examining The Decline Of Honey Bees | Earth Wise

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For many years, scientists have been sounding the alarm on the global struggle of pollinators.  Many of the invertebrate pollinator species, such as bees and butterflies, are facing extinction. And since 75% of the world’s food crops depend on pollination to some extent, the decline of pollinators poses a major threat to global food security.

Honey bees are among the struggling pollinators.  Over the past 14 years, bee colonies have been disappearing at an alarming rate in what is known as the “colony collapse disorder.” 

In an effort to understand why, scientists have often focused their research on environmental stressors, such as parasites, pesticides, and disease.  But according to new research by entomologists from the University of Maryland, honey bee life spans are simply 50% shorter today than they were 50 years ago.  In the study, which was recently published in the journal Scientific Reports, the researchers found that honey bees kept in a controlled, laboratory environment lived half as long as honey bees did in the 1970s.  This is the first study to show that genetics – as opposed to environmental stressors – may be influencing the broader trends seen in the beekeeping industry.

When the researchers modeled the effect of their findings on a beekeeping operation, they found that the resulting loss rates were about 33%.  This is similar to the average overwinter and annual loss rates reported by beekeepers during the past 14 years.

The next step is for researchers to compare trends in honey bee life spans across the U.S. and in other countries to see if there are differences in bee longevity. 

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Honey Bee Lifespans are 50% Shorter Today Than They Were 50 Years Ago

Helping Agriculture’s Helpful Honey Bees

Photo, posted June 23, 2007, courtesy of Susan E. Ellis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Moving Endangered Species | Earth Wise

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People have intentionally or accidentally introduced numerous invasive species to habitats around the world.  At the same time, the planet’s wildlife is in a steep decline.  A recent study estimated that the populations of over 5,000 vertebrate species have declined by an average of nearly 70% since 1970.  A United Nations report warns that human activity has threatened as many as a million species with extinction.

With all of this as a background, there is climate change that is altering the habitats of the world’s species – warming lakes and oceans, turning forests into grasslands, tundra into woodland, and melting glaciers.  In response to these changes, living things are rearranging themselves, migrating to more hospitable locations.  But many species are just not capable of finding more suitable habitats on their own.

Conservationists are now increasingly considering the use of assisted migration. In some cases, when a species’ critical habitat has been irreversibly altered or destroyed, agencies are establishing experimental populations outside of the species’ historical range.  Such actions are often deemed extreme but may be increasingly necessary.

However, clear-cut cases are relatively rare.  More likely, it is a more difficult judgement call as to whether assisted migration is a good idea or is possibly a threat to the ecosystem of the species’ new location.  The relative dearth of assisted migration experiments is less likely a result of legal barriers than it is a lack of scientific and societal consensus on the practice. Scientists are now trying to develop risk-analysis frameworks that various agencies can use in considering potential assisted migration experiments. 

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Last Resort: Moving Endangered Species in Order to Save Them

Photo, posted March 18, 2010, courtesy of Jean via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Pacific Bluefin Tuna On The Rebound | Earth Wise

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The Pacific Bluefin Tuna is a commercially valuable species that is especially prized in Japan.  The fish is particularly valued for sashimi and sushi and large specimens have been known to fetch enormous prices at seafood auctions.

Aggressive fishing reduced the bluefin biomass through the late 1990s and 2000s to only a few percent of its potential unfished levels.  Beginning in 2011, The Western and Central Pacific Fisheries Commission began management measures that reduced the catch of smaller bluefin as well as limited the catch of larger bluefin.  The goal was to allow more fish to grow to maturity.  The Inter-American Tropical Tuna Commission adopted similar resolutions a year later.  Despite these efforts, increasing concern about declining bluefin levels led to a petition to list the species as endangered.  The National Oceanic and Atmospheric Administration’s Fisheries organization determined that while the population was near historical lows, the remaining 1.6 million fish was a sufficient number to avoid the risk of extinction and that the measures in place were sufficient.

A new assessment of the bluefin population has shown that the species is now increasing and includes many younger fish that will help accelerate its rebound.  The assessment by NOAA showed that the bluefin stock was greater than the first rebuilding target set for 2019. 

According to the NOAA Fisheries biologists that performed the assessment, the species has responded exactly as predicted given the actions that were taken.  The bluefin tuna is an amazingly resilient fish and it is continuing to demonstrate that fact.

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International Actions Pay Off For Pacific Bluefin Tuna as Species Rebounds at Accelerating Rate

Photo, posted June 1, 2022, courtesy of Philippe Yuan 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.

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