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Glacial Loss In The Swiss Alps | Earth Wise

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In 2022, glaciers in the Swiss Alps melted more than in any year on record.   This is the latest piece of bad news for the country’s glaciers, which have lost more than half of their volume of ice since the 1930s.

The melting season for Switzerland’s snow and ice typically starts in May and ends in early October.  This year’s melting season caused glaciers in the Diablerets mountain group to thin by an average of 13 feet, which is 3 times the amount of thinning observed over the past decade.   The Tsanfleuron pass between two of the glaciers is now exposed as bare rock for the first time in several thousand years. Across Switzerland, glaciers lost about 6% of their remaining volume just this year.  The previous worst year for glaciers was 2003, when losses were nearly 4%. 

There was significant melting this year in part because of the small amount of snowfall over the winter.  That snow melted quickly, being sped up by the warming effect of dust from the Sahara Desert falling on the snow.  By early summer, there was no longer a protective blanket of snow on the glaciers, exposing them to summer heat.

The loss of glaciers is far more serious than the disappearance of aesthetically pleasing landscape features.   Glaciers act as reservoirs of water that persist through the summer months.  Melt from glaciers provides water to ecosystems and creates habitats for plants and animals.  Cold runoff from glaciers affects downstream water temperatures which have a major impact on insects, fish, and other creatures.  Globally, melting glaciers contribute more than 20% of the observed ongoing sea-level rise.

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Rocky Road for Swiss Glaciers

Photo, posted June 22, 2015, courtesy of Dennis Jarvis 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

Planting Millions Of Trees Isn’t So Easy | Earth Wise

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There are initiatives around the world to plant millions of trees as a way to fight climate change.  Unfortunately, scientists have observed that many of these projects are ill-conceived and poorly managed.  Some have failed to grow any forests at all.

One such project was an attempt to plant a million mangrove seedlings in coastal mud on the Filipino island of Luzon in 2012.  Ten years later, less than 2% of the trees have survived.  The other 98% have died or have washed away.  The problem was that the site of the project was ecologically unsuited to mangroves because it is too waterlogged and there is no oxygen available except in a few sheltered spots.

In 2019, the Turkish government managed the planting of 11 million trees in 2,000 sites across the country.  A later survey found that 90% had died, although the government denies that assertion.

Many other projects have also had dismal results.  The causes of failure vary but include planting single species of trees that become vulnerable to disease, competing demands for land, changing climate, planting in areas not previously forested, and lack of ongoing care for the saplings including watering them.

Nobody is opposed to mass tree planting.  There is no anti-tree lobby.  But tree planting is sometimes a form of greenwashing.  It is great for public relations but unless it is done properly with appropriate planning, it can be a waste of effort and money.  The result can be a phantom forest that does nothing for the climate.

Forest planting can work if the social and environmental conditions are right, and if planting is followed by long-term monitoring and care of the trees.

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Phantom Forests: Why Ambitious Tree Planting Projects Are Failing

Photo, posted April 20, 2016, courtesy of the U.S. Navy / Mass Communication Specialist 2nd Class John Benson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Coping With Climate Change | Earth Wise

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

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

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

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

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

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

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Which animals can best withstand climate change?

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

Earth Wise is a production of WAMC Northeast Public Radio

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.

What Is Healthy Soil? | Earth Wise

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Soil supports life by providing many critical ecosystem services.  For example, soil acts as a water filter, a growing medium, and provides habitat for billions of organisms.  Soil is also the foundation of our cities and towns, and the basis of global agroecosystems, which provide humans with feed, fiber, food, and fuel.

For all of these reasons and many more, having healthy soil is vital.  But what does soil health mean? And how should it be measured?

According to new analysis by researchers from Cranfield University and Nottingham University in the U.K., how we think about, measure, and study soil must change in order to better understand how to manage this resource effectively. 

While the term ‘soil health’ is widely used, it means different things to different people.  There is no single agreed upon way to gauge the overall health of soil. 

Current approaches to assess soil health measure individual soil properties and use findings  to assign a single number giving an overall score.  But according to the research team, this does not reflect the wider system perspective that’s needed to fully evaluate the health of soil over time.

Instead, the researchers propose a new system to assess soil health based on a hierarchical framework that takes in several measures, including signs of life, signs of function, signs of complexity, and signs of emergence, which is the extent to which soils recover from multiple stressors. 

This new approach, which can be applied to all soils, moves us closer to an interdisciplinary understanding of the whole picture of soil health.  After all, healthy soil is fundamental to our survival.

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We need to change how we think about soil

Photo, posted April 8, 2008, courtesy of Brian Boucheron 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.

Life In The Great Pacific Garbage Patch | Earth Wise

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The world’s oceans contain five gyres, which are large systems of circular currents created by global wind patterns and the Earth’s rotation.   Gyres act like gigantic whirlpools.  Anything that floats into one of them eventually ends up in the center.   Ever since floating plastic waste started entering the ocean, it has poured into these gyres and created so-called garbage patches.  The largest of these is the Great Pacific Garbage Patch, located halfway between Hawaii and California.  According to the Ocean Cleanup Foundation, the Great Pacific Patch contains at least 79,000 tons of plastic.

A recent study has shown that the garbage patch is not just a place where drifting plastics aggregate; it is also a place where drifting animals aggregate.

It turns out that the Great Pacific Garbage Patch is absolutely teeming with life, primarily small surface-dwelling animals that are collectively known as neuston.  A ship surveying the garbage patch found that in some places, there were nearly as many neuston as there are pieces of plastic.

Typical creatures in the patch are blue dragon nudibranchs, Portuguese man-o-wars, anemones, sea snails, blue buttons (which are related to jellyfish) and hydrozoans.  It appears that these creatures are reproducing within the garbage patch.  Little is actually known about the life history and ecology of these creatures, so that studying the garbage patch is offering valuable insights to scientists.

Two nonprofit organizations are working to remove floating plastic from the Great Pacific Garbage Patch.  Evidently, removing this existing pollution from the ocean is likely to have unexpected effects on the local ecosystem and is a source of at least some controversy.  One thing that isn’t controversial, however, is that we need to stop the flow of plastic into the ocean.

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The Ocean’s Biggest Garbage Pile Is Full of Floating Life

Photo, posted in April, 2012, courtesy of Steven Guerrisi 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.

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.

Tourism And Invasive Species | Earth Wise

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Tourism has experienced exponential growth during the past 70 years.  In 1950, there were 25 million international tourist arrivals.  By 1990, it had ballooned to 435 million.  Between 1990 and 2018, the numbers more than tripled reaching more than 1.4 billion.  And by 2030, the number of international tourist arrivals is expected to reach 1.8 billion.

Tourism is vital to the success of many economies around the world.  Tourism can boost revenue, provide jobs, develop infrastructure, protect wildlife, and help preserve heritage sites and cultures.  But there can also be many downsides to tourism, one of which is that it can contribute to the introduction and spread of invasive species.  Non-native organisms can cause all sorts of social, environmental, and economic damage.   

Tourists help spread invasive organisms far and wide.  These organisms hitch rides in their luggage and on their shoes and clothing.  A 2011 study in New Zealand found that for every gram of soil on the shoes of in-bound international passengers, there were 2.5 plant seeds, 41 roundworms, 0.004 insects and mites, and many microorganisms. 

A new study by researchers from the University of Melbourne in Australia and AgResearch New Zealand examined to what degree tourism plays a role in the spread of invasive species.  According to the study, which was recently published in the journal NeoBiota, the research team found that the number of nights spent in hotels significantly correlated to the incursion of invasive species during that period.

Creating effective mechanisms to prevent the introduction of invasive species in the first place is the best way to prevent this problem. 

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Unwelcome guests: International tourism and travel can be a pathway for introducing invasive species

Number of tourist arrivals

Photo, posted March 27, 2005, courtesy of John via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Polar Bears And Melting Sea Ice | Earth Wise

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Climate change poses a major threat to polar bear survival.  The polar bear, whose native range lies largely within the Arctic Circle, depends on sea ice for nearly all of its lifecycle functions.  And rising temperatures are causing this sea ice to disappear.

Climate change-driven sea ice loss is the primary threat to the future of this iconic species.  In fact, polar bears were the first animal listed as endangered because of the forecasted impacts of climate change.   

Melting sea ice as a result of climate change continues to plague polar bear survival.  According to a new study by researchers from Washington State University, polar bears in the Beaufort Sea have had to travel far outside their traditional arctic hunting grounds in recent years for food.  This has contributed to an almost 30% decrease in their population. 

Researchers used satellite tracking data to analyze the movement patterns of female polar bears from 1986-2016 in the Beaufort Sea area north of Alaska.  Over the last two decades, they found that polar bears are having to travel farther north of their traditional hunting grounds on the continental shelf to remain on their receding sea ice habitat.

The research team also found that around 20% of the polar bear population in the Beaufort Sea is foregoing its traditional sea ice hunting grounds altogether in the summer and fall.  Instead, these bears are moving inland in search of food.  

Scientists estimate that 800 or so polar bears remain in the southern Beaufort Sea.  Curbing global greenhouse gas emissions in order to protect polar bear habitat may be the only way to help these animals survive. 

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Melting sea ice forces polar bears to travel farther for food

Photo, posted September 27, 2015, courtesy of Anita Ritenour via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Snakes Near A Plane | Earth Wise

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San Francisco International Airport is the seventh-busiest airport in the United States.  In a typical year, approximately 55 million people pass through SFO on their way to destinations throughout North America and beyond.

At some point during their journey to or from the terminals at SFO, each one of those people will pass by a seemingly unremarkable 180-acre parcel of land.  Surrounded by highways and train tracks, the soggy and overgrown vacant lot isn’t just home to rows of power lines.  It’s also home to the world’s largest population of the beautiful and highly endangered San Francisco garter snake.   

According to a recent study conducted by the U.S. Geological Survey, there are approximately 1,300 San Francisco garter snakes at SFO’s West of Bayshore property – the greatest concentration of these snakes ever recorded.

Conservationists have long known that the San Francisco garter snake was in trouble.  In fact, it landed on the U.S. Fish and Wildlife Service’s very first endangered species list, which was published in 1967.  Over the years, agricultural, commercial, and urban development have destroyed much of its wetland habitat, as well as much of its primary food source, the California red-legged frog.  The snakes have also been a popular target for poachers and collectors.

Since 2008, SFO has been working with the USFWS on a recovery strategy for the species.  Together, they’ve made enhancements to the West of Bayshore habitat, including building rainfed ponds and deepening existing wetlands.  They have also added fences to protect habitat and prevent illegal collection.

But low population counts at other locations means the recovery for the San Francisco garter snake is far from over. 

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Combining genetic and demographic monitoring better informs conservation of an endangered urban snake

A San Francisco Airport Site Is Crawling With Snakes—And That’s a Good Thing

Photo, posted April 16, 2011, courtesy of Brian Gratwicke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Coral Reefs And Fish Survival | Earth Wise

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The precarious state of the world’s coral reefs has been a highly visible subject for a decade or more.  Mostly what we hear about is the loss of some of the most beautiful sights on the planet. But there is far more at stake than scenic wonders.

The warming and acidifying of ocean waters are causing corals to increasingly bleach and often die.  Corals provide a unique food source for some species of fish and a three-dimensional habitat for many others.  The fish that depend on corals are often prey for fish that don’t depend directly on corals and so on up the food chain.

What happens to fish when coral reefs disappear?  The fish species that feed on corals will starve while others will seek alternative rocky habitats.

A new study by the University of Helsinki uses statistical methods to predict how fish diversity will respond to declines in coral diversity. It concludes that a future coral loss might cause a 40% reduction in reef fish diversity globally.  This is more than a loss of colorful sights for snorkelers; reef fishes provide essential protein for millions of people around the world.

The estimate of potential loss of fish species greatly exceeds the number of species known to depend directly or even indirectly on coral.  The implication is that coral reef food webs will begin to unravel if corals go extinct.  This unraveling is expected to be worse in some places than others.  The Central Pacific, for example, could lose 60% of its reef fish.

For both snorkelers and for the millions who depend upon reef fishes for food, the need for greater efforts to conserve and restore coral reefs is apparent.

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A fu­ture ocean that is too warm for cor­als might have half as many fish spe­cies

Photo, posted September 27, 2009, courtesy of Matt Kieffer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Marine Debris | Earth Wise

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Marine debris is a troubling issue around the world.  For most people, it is unsightly and perhaps inconvenient, but for many it is a critical problem that has serious impacts on many aspects of life.  This is especially the case for indigenous communities for whom the natural environment around the ocean is central to subsistence, recreation, culture, and economic opportunities.

The National Oceanic and Atmospheric Administration sponsors a Marine Debris Program that supports multiple projects.  In Alaska’s Pribilof Islands, the indigenous communities of St. George and St. Paul Islands conduct regular cleanups to protect and steward the natural resources that they depend on.  They make use of unmanned aircraft system surveys to target removal and monitoring efforts.

Another NOAA-sponsored program works to clean up the Maybeso Estuary in Alaska’s Prince of Wales Islands.  The project has removed 35,000 pounds of debris, freeing the flow of the salmon stream and restoring the area as a prime hotspot for fishing, boating, and outdoor recreation.

In Washington State’s Olympic Coast, the Makah Tribe has a project to locate and remove derelict crab pots and fishing lines from 80 miles of fishing area and marine sanctuary.  Derelict fishing gear can trap and entangle animals, degrade habitat, imperil navigation, and interfere with fishing.  The project team is working with tribal stakeholders on promoting marine debris awareness.

All of these communities have cared for the environment for generations, but marine debris poses perilous threats to their territories and community action is needed to preserve and protect these remarkable places.

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Lives and Livelihoods Disrupted by Marine Debris

Photo, posted September 11, 2015, courtesy of NOAA’s National Ocean Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The World’s Largest Harmful Algal Bloom | Earth Wise

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Brown sargassum seaweed floats in surface water in a bloom that stretches all the way from West Africa to the Gulf of Mexico.  Sargassum provides habitat for turtles, crabs, fish, and birds.

The stuff carpets beaches along the tropical Atlantic, the Caribbean Sea, the Gulf of Mexico, and the east coast of Florida disrupting tourism.  Florida’s Miami-Dade County alone spends $45 million a year cleaning up sargassum.  Annual Caribbean clean-up is in excess of $120 million.

A study by Florida Atlantic University has discovered dramatic changes in the chemistry and composition of sargassum which has transformed the so-called Great Atlantic Sargassum Belt into a toxic dead zone.

The findings of the study suggest that increased nitrogen availability from both natural and human-generated sources, including sewage, is supporting blooms of sargassum and turning a critical marine nursery habitat into harmful algal blooms with catastrophic impacts on coastal ecosystems, economies, and human health.

The study found that today’s sargassum tissues compared with those of the 1980s have 35% more nitrogen content and 42% less phosphorus.  Much of the nitrogen increase is a result of agricultural and industrial runoff from the Congo, Amazon, and Mississippi Rivers. 

The fact that the bloom itself has expanded so tremendously was already suspected to be the result of significant changes in the ocean’s chemistry.  Given the negative effect that the Great Atlantic Sargassum Belt is having on the coastal communities, additional research is essential to guide mitigation and adaptation efforts.

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Sargassum now world’s largest harmful algal bloom due to nitrogen

Photo, posted June 5, 2016, courtesy of J Brew via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Surviving Climate Change | Earth Wise

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The sixth mass extinction of wildlife on Earth is happening now.  According to an analysis published last year in the journal Proceedings of the National Academy of Sciences, more than 500 species of land animals are on the brink of extinction and are likely to be lost within the next 20 years. Without the impact of humans, this quantity of extinctions would have taken thousands of years. 

Anthropogenic climate change continues to exacerbate problems that drive species to the brink.  Which species will be able to adapt and survive?

Using genome sequencing, a research team from McGill University in Montreal has found that some fish, like the threespine stickleback, can adapt very rapidly to extreme seasonal changes. Known for their different shapes, sizes, and behaviors, stickleback fish can live in both saltwater and freshwater, and can tolerate a wide range of temperatures.

Stickleback fish, which can be found in different estuaries along coastal California, provided researchers with an opportunity to study natural selection in real-time.  The researchers analyzed six populations of threespine stickleback fish before and after seasonal changes to their environment.   The research team discovered evidence of genetic changes driven by the seasonal shifts in habitat that mirrored the differences found between long-established freshwater and saltwater populations.  Since these genetic changes occurred in independent populations over a single season, the study highlights just how quickly the effects of natural selection can be detected. 

These findings suggest that scientists may be able to use the genetic differences that evolved in the past as a way to predict how species may adapt to climate change in the future.

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Which animals will survive climate change?

Sixth Mass Extinction of Wildlife Accelerating- Study

Photo, posted August 3, 2015, courtesy of Jason Ching/University of Washington via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Vanishing Kelp Forests | Earth Wise

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Bull kelp is the dominant species in offshore kelp forests north of Santa Cruz, California along the west coast of North America.  Bull kelp has similar physical structures to terrestrial plants; it anchors to the ocean floor with root-like structures called holdfasts, and has stem-like structures called stipes from which leaf-like blades stretch out through the water, absorbing nutrients and sunshine.

These giant seaweeds form lush underwater forests in northern California’s coastal waters and have long provided critical habitat for many species like salmon, crabs, and jellyfish.  But now, for much of the California coast, only a few patches of bull kelp remain.

A team from University of California Santa Cruz has studied satellite images of about 200 miles of coastline.  They found that starting in 2014, the area covered by kelp has dropped by more than 95%. 

The die-off was driven in part by an underwater heat wave that depleted nutrients in the water and made it harder for the kelp to grow.  Making matters much worse, populations of purple sea urchins, which eat kelp, have exploded in the region because of overfishing and other reductions in urchin predators such as sea otters.  The sea urchins eat kelp holdfasts, creating so-called urchin barrens where their destructive grazing has decimated kelp forests.

Bull kelp is a species at high risk of becoming endangered.  In coming decades, more marine heatwaves are expected.  These events as well as stronger El Niños will become more common and frequent with climate change.  Between these thermal events and the sea urchins, it will be difficult for kelp forests to survive.

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Ninety-five percent of bull kelp forests have vanished from 200-mile stretch of California coast

Photo, posted October 28, 2015, courtesy of Florian Graner/Green Fire Productions via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting The Ocean Has Multiple Benefits | Earth Wise

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An international team of authors from 18 institutions has recently published a paper in the journal Nature that offers a solution that addresses several of humanity’s most pressing problems at the same time.  The paper provides a comprehensive assessment of where strict ocean protection can contribute to a more abundant supply of healthy seafood, help address climate change, and protect embattled species and habitats.

The study identified specific areas of the ocean that could provide all of these benefits if they were protected.  Currently, only about 7% of the ocean is under any kind of protection.  According to the study, if the appropriate 30% of the ocean was protected by the actions of the relevant countries by 2030, the cited benefits would be realized.

Safeguarding these regions would protect nearly 80% of marine species while increasing fishing catches by almost 9 million tons a year. It would also prevent the release of more than 1 billion tons of carbon dioxide by protecting the seafloor from bottom trawling, which is a widespread and destructive fishing practice.

Ocean life has been declining worldwide because of overfishing, habitat destruction, and climate change.  The study pioneers a new way to identify the places that – if protected – will boost food production and safeguard marine life, while at the same time reducing carbon emissions.  The study finds that countries with large national waters and large industrial trawl fisheries have the highest potential to contribute to climate change mitigation by protecting the carbon stored on the ocean floor.  The ocean covers 70% of the Earth and its importance in solving the challenges of our time must not be underestimated.

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Three Times the Gains

Photo, posted January 10, 2016, courtesy of Hafsteinn Robertsson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Nature Is Valuable | Earth Wise

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A study by the University of Vermont, the University of Cambridge, and several other institutions compared the value of protecting nature at particular locations with that of exploiting it.   The study concluded that the economic benefits of conserving or restoring natural sites outweigh the profit potential of converting them for intensive human use.

The study analyzed dozens of sites across the globe – from Kenya to Fiji and China to the UK across six continents.  It was published in the journal Nature Sustainability.

The analysis utilized a methodology devised ten years ago called TESSA (the Toolkit for Ecosystem Service Site-based Assessment) which enables users to measure, and in many cases, assign monetary values to services provided by sites – clean water, nature-based recreation, crop pollination, and so on.  This is then compared with the economic benefits that can be derived by converting the site for farming, logging, or other human uses.

A major economic benefit of natural sites comes from their ability to sequester carbon and thereby help regulate the quantity of greenhouse gases in the atmosphere.  If one assigns a value to global society of $31 a ton of carbon removed, over 70% of the sites surveyed had a greater value to society when kept natural rather than being converted.  Many scientists actually consider this carbon price to be conservative.  Nevertheless, if carbon is assigned the paltry cost of $5 a ton, 60% of the sites are still more valuable in their natural state.

Beyond these economic calculations, there is the pressing issue that current rates of habitat conversion are driving a species extinction crisis unprecedented in human history.  But even if one is only interested in dollars and cents, conserving and restoring nature is now very often the best bet for human prosperity.

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Economic Benefits of Protecting Nature Exceed Value of Exploiting it, Global Study Finds

Photo, posted June 7, 2017, courtesy of Mouli Choudari 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...)