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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.

Rewilding The American West | Earth Wise

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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.

Return Of The Fin Whale | Earth Wise

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The fin whale is the second largest whale species and therefore the second largest creature on Earth.  They can grow to more than 80 feet in length.  From 1904 to 1976, there was massive industrial whaling in the Southern Ocean surrounding Antarctica.  During that period, whalers killed about 700,000 fin whales, reducing their population by 99%.  The species was nearly extinct.

In 1982, the International Whaling Commission voted to ban commercial whaling.  Since that time, fin whales started to make a comeback in their historical feeding grounds.

During a nine-week expedition in the waters around the Antarctic Peninsula, researchers encountered the largest gathering of fin whales ever documented.  About 150 fin whales were seen diving and lunging against the water’s surface.  It was a feeding frenzy triggered by large amounts of krill in the water.  The actions of the whales are known as a “whale pump” that drives the krill to the surface.  Not only does it provide huge amounts of food for the whales but also for other animals, including seabirds and seals.

Forty years after the commercial whaling ban, the number of fin whales has been increasing.  Large groups were observed in a 2013 survey.  Aerial surveys in 2018 and 2019 recorded 100 groups of fin whales, usually composed of a just a handful of individuals.  They did document eight large groups of up to 150 individuals.

Not all species of whales have rebounded so successfully since the whaling ban.  The rebound in fin whale population is not only good for the whales, but for the entire ecosystem in the Southern Ocean.  It is a glimmer of good news in a time of great challenges for global biodiversity and for marine life in particular.

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Once Facing Extinction, Massive Fin Whales Have Returned to Antarctic Waters

Photo, posted November 15, 2007, courtesy of Gregory Smith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Some Good Monarch News | Earth Wise

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Eastern monarch butterflies spend their winter months in central Mexico.   Every spring, they embark on a lengthy, multigenerational migration that takes them into the United States and even into southern Canada, where they breed.  The butterflies go through several generations before they eventually migrate back to Mexico.

Twenty-five years ago, overwintering monarchs in Mexico blanketed nearly 45 acres of forest.  The acreage covered, which has been surveyed annually since 1993, is a rough indicator for the actual number of butterflies that survive the difficult migration process. In 2013, the monarchs occupied only 1.6 acres of Mexican forest.  The butterflies were deemed to be on the edge of extinction.

Last December, the monarch survey found 7 acres covered by the butterflies, an increase of 35% over the previous winter.  The population appears to be steadily rebounding, although the numbers are still substantially lower than the levels seen in the 1990s.

The butterflies are struggling with multiple problems.  There continues to be a lack of milkweed, the only food source for the caterpillars, in their breeding grounds along their migratory route.  More extreme weather driven by climate change is another challenge, and illegal logging in their overwintering habitat in Mexico has also become a threat.

After the butterfly population crashed in 2013, conservation efforts shifted into high gear with lots of milkweed planting in the US and Canada, and crackdowns on timber poachers in Mexico.

The remarkable multigenerational migration of monarchs is a delicate phenomenon that can be disrupted by many different things.  Eastern monarchs are still in serious danger, but the current trend seems to be positive.

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Warming Trends: Butterflies Bounce Back, Growing Up Gay Amid High Plains Oil, Art Focuses on Plastic Production

Photo, posted August 12, 2021, courtesy of Paul VanDerWerf via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Red Pandas And Climate Change | Earth Wise

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

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

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

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

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

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

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Red pandas face a fractured future

IUCN: Red Panda

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

Earth Wise is a production of WAMC Northeast Public Radio.

Declining Flying Insects | Earth Wise

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In recent years, there has been increasing awareness of the global decline in insect abundance.  A recently published survey of the abundance of flying insects in the UK has revealed very troubling results.

The Kent Wildlife Trust and Buglife – two UK-based conservation groups – compared the number of dead insects on vehicles in 2004 and 2021.  In this Bugs Matter Citizen Science Survey, the data was collected by roughly 20,000 ordinary citizens using a smartphone app.

The results were that the number of flying insects in Britain dropped nearly 60% over that time period.  The insects declined most in England and Wales, with drops of 65% and 55%, respectively. 

It is possible that 2004 was a particularly good year for British insects and 2021 an especially bad one, but the findings of this study are consistent with other research around the world showing an alarming decline in insects.  A series of studies in 2019 found that the global mass of insects is shrinking by 2.5% a year and that insects are going extinct eight times faster than reptiles, birds, or mammals.

Insects face multiple overlapping threats including the destruction of wild habitats for farming, urbanization, pesticides, and light pollution.  On top of these things is climate change which is disrupting ecosystems in multiple ways.

Insects play a vital role in pollinating crops, consuming organic waste, killing pests, and as essential parts of multiple ecosystems.  Severe insect declines can potentially have dire global ecological and economic consequences.

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Flying Insects Have Declined by 60 Percent in the U.K., Survey Finds

Insect decline in the Anthropocene: Death by a thousand cuts

Photo, posted May 6, 2007, courtesy of Richard Giddins via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Is It Too Late To Save The Vaquita? | Earth Wise

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The vaquita porpoise, the world’s smallest marine mammal, is on the brink of extinction.  Scientists estimate that just 10 or fewer vaquitas are left despite international conservation efforts. Found only in Mexico’s Upper Gulf of California, the vaquita is the most endangered marine mammal on the planet. 

According to the International Committee for the Recovery of the Vaquita, the number one threat facing vaquitas is gillnets. The porpoises get trapped in these nets and drown.  Gillnets are often used illegally in the region to catch shrimp and fish, including the critically-endangered totoaba.  The totoaba’s swim bladder is considered a delicacy in Asia and can fetch thousands of dollars.  Despite Mexico banning both totoaba fishing and the use of gillnets in the vaquitas’ habitat, many say the bans are not always enforced.  

But there is a reason to be hopeful.  According to a genetic analysis led by researchers at UCLA, the critically-endangered species actually remains relatively healthy and can potentially survive if illegal fishing practices cease immediately. 

In the study, which was recently published in the journal Science, the research team analyzed the genomes of 20 vaquitas between 1985 and 2017 and ran simulations to predict the species’ extinction risk over the next 50 years.  The researchers concluded that if gillnet fishing ends immediately, the vaquita has a very high chance of recovery.  If the practice continues, however, even moderately, the likelihood of a recovery plummets. 

According to the research team, the surviving vaquitas are actively reproducing and seem healthy.  But poachers’ gillnets will continue to pose an existential threat to the species until more measures are taken to protect the vaquita. 

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Only 10 vaquita porpoises survive, but species may not be doomed, scientists say

Photo, posted October 18, 2008, courtesy of Paul Olson / NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Record Levels Of Deforestation In The Amazon | Earth Wise

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The Amazon rainforest is the largest rainforest in the world, covering more than 2.5 million square miles.  It’s home to 10% of all known species in the world.  The Amazon rainforest’s biodiversity is so rich that scientists are still discovering new plant and animal species today.  

The Amazon rainforest absorbs huge amounts of carbon dioxide from Earth’s atmosphere, making it a key part of mitigating climate change.  The vast rainforest acts as what’s known as a carbon sink.  Simply put, a carbon sink is anything that absorbs more carbon from the atmosphere than it releases.  But as trees in the Amazon disappear, so does the ability of the rainforest to absorb carbon dioxide.

Deforestation of the Amazon rainforest remains a major problem.  According to satellite data from the Brazilian government, the number of trees cut down in the Brazilian Amazon in January far exceeded deforestation figures for the same month last year.  Approximately 166 square miles of land was deforested in January alone, which is five times greater than what was lost in January, 2021.

Cattle ranching – both for beef and for leather – remains the leading cause of deforestation in the Amazon rainforest.  Trees in the Amazon are also cut down for their wood, as well as to clear the land in order to grow food crops, such as soy, sugar, and oil palm. 

Many companies have pledged to achieve “net zero” deforestation in their supply chains over the years, but most have not lived up to the commitment. 

Deforestation is not only a major driver of climate change, but it’s also the leading cause of species extinction.  Preserving the Amazon rainforest is vital. 

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Amazon deforestation: Record high destruction of trees in January

Greenpeace calls on fast food giants to take a stand against Bolsonaro’s Amazon destruction

Hundreds of Companies Promised to Help Save Forests. Did They?

Photo, posted July 14, 2018, courtesy of Alexander Gerst via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Koalas Are Endangered | Earth Wise             

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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.

The Sixth Mass Extinction | Earth Wise

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Extinction is a natural part of life.  Plants and animals disappear all the time.  When one species goes extinct, its place in the ecosystem is typically filled by another.  The so-called normal rate of extinction is thought to be somewhere between 0.1 and 1 species per 10,000 species per 100 years.

A mass extinction event is when species disappear at a much faster clip than they can be replaced.  By definition, mass extinction is when about three-quarters of the world’s species are lost in a short amount of time on a geologic scale, which is measured in millions of years.  

There have been five previous mass extinction events throughout the history of life on earth.  Today, many experts warn that a sixth mass extinction event is already underway – the first since dinosaurs were wiped out some 65 million years ago.  While previous mass extinctions were the result of extreme natural phenomena like volcanic eruptions and asteroid strikes, this one is a result of human activities. 

Researchers from the University of Hawai’i at Manoa and the National Museum of Natural History in France recently published a comprehensive assessment of evidence of this ongoing extinction event.  The researchers estimated that since the year 1500, Earth could already have lost between 7.5% and 13% of the two million known species on Earth.  This amounts to a staggering 150,000 to 260,000 species.

While mitigating the effects of climate change and reducing the rates of habitat loss would help, raising awareness of this crisis and its fallout for all life forms – including us – would be most effective in driving change. 

The time we have to avoid dramatic consequences is rapidly running out. 

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Strong evidence shows Sixth Mass Extinction of global biodiversity in progress

Photo, posted September 18, 2015, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Lake Tuz Is Disappearing | Earth Wise

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Lake Tuz is Turkey’s second-largest lake and one of the world’s largest hypersaline lakes.  Its high salt content makes it an ideal breeding ground for some migratory bird species, including flamingos, which are often present there in huge numbers in the spring and summer.

Now, Lake Tuz rarely spans an area much larger than a puddle. In some summers, it completely dries up.  It did so this past summer, which resulted in the deaths of thousands of flamingos.

According to experts, Lake Tuz is a victim of climate change-induced drought, which has hit the region hard, and decades of harmful agricultural policies that exhausted the underground water supply.

Water in this region has become increasingly scarce.  The Mediterranean Basin has already seen more frequent and intense droughts, and is considered a climate change hotspot. 

According to new research, which was recently published in the journal Regional Environmental Change, Lake Tuz generally contained enough water in August for the lake to be considered permanent up until 2000.  But between 2001 and 2016, something shifted.  Water spanned less than 20% of the lake in every August except for one, and droughts became more frequent and intense. And in some years, the lake completely dried up.   

What caused this change?  According to the research team, Lake Tuz’s decline coincided with the excessive use of groundwater and surface water resources responsible for feeding the lake.  Some streams were rerouted for agricultural purposes, while others were dammed.  And when surface water sources dwindled, people turned to groundwater that historically fed the springs in Lake Tuz. 

Lake Tuz may be on the brink of extinction. 

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Impact of climate variability on the surface of Lake Tuz (Turkey), 1985–2016

Disappearing Lake Tuz

Photo, posted August 16, 2021, courtesy of Godot via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Crops Threatened With Extinction | Earth Wise

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Crop variety and diversity are critically important for global food security as well as for the livelihoods of millions of people.  This diversity entails both the different species of food crops as well as the so-called farmer varieties of crops that in many cases have been cultivated and safeguarded for millennia.

It is well-known that many of these crops and varieties have been rapidly disappearing, but data has been scarce on just how many have been lost, how many we are losing, and which ones are the most threatened going forward.

A new study utilizes a methodology known as the Varietal Threat Index, which was developed by the Alliance of Bioversity International and CIAT, the International Center for Tropical Agriculture.  The study assessed about 600 farmers from seven Indian states, covering five different agroecological areas.  The farmers were selected based on their knowledge of crops and varieties across the 17 study sites.

The farmers listed the crops and varieties grown in their households, noted their uses, and indicated their spread and abundance, including information on varieties grown during the previous ten years which were no longer grown.

The results of the study showed that while there is a significant diversity of landraces – which are local varieties of species developed over time – more than 50% are threatened.  The trend is that crops and varieties mostly used for consumption are most often under threat, whereas varieties with multiple uses are less likely to be threatened.

Studies of this type can aid the development of targets and indicators to monitor the global status of plant genetic resources for food and agriculture and help inform urgent priority conservation actions.

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More than half of surveyed crop varieties are under threat of extinction, according to study in India

Photo, posted February 21, 2014, courtesy of Atibordee Kongprepan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Butterflies And Moths In A Changing World | Earth Wise

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Extinction is a part of life.  Plant and animal species disappear all the time.  In fact, approximately 98% of all the organisms that have ever existed on planet earth are now extinct. Earth’s so-called ‘normal’ rate of extinction is thought to be somewhere between 0.1 and 1 species per 10,000 species per 100 years. 

But anthropogenic climate change is bringing about rapid change in nature. Put more simply, human activity is killing nature at an unprecedented rate.  According to many scientists, the earth’s sixth mass extinction has already begun. Mass extinctions are defined as times when the Earth loses more than 75% of its species in a geologically short interval.

The changing climate puts immense pressure on species for change.  According to a new study by researchers from the University of Helsinki and the Finnish Environment Institute, the few butterfly and moth species capable of adjusting to the changing climate by moving up their flight period and moving further north have fared the best.

In Finland, researchers compared temporal shifts in the flight period and spatial shifts in the northern range boundary of 289 moth and butterfly species, as well as changes in abundance over a roughly 20-year period.

They found that about 45% of species that either moved northward or advanced their flight period fared much better than the roughly 40% of species that did not respond in either way.  On average, the populations of these poorly responding species declined.  But the 15% of species that did both had the largest increase in abundance. 

The ability to adapt to a changing climate is going to be vital for species survival. 

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Butterflies and moths have difficulty adjusting to a rapidly changing climate

What is mass extinction and are we facing a sixth one?

Photo, posted August 16, 2017, courtesy of Tero Laakso via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)