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Birds Are Disappearing

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A new analysis, published in the journal Science, reports that the number of birds in the United States and Canada has fallen by 29% since 1970.  There are 2.9 billion fewer birds in the two countries now than there were 50 years ago.

The analysis is the most comprehensive attempt to date to look at the status of avian populations.  The results were a shock to researchers and conservation organizations.

It is well-known that some bird species have become vulnerable to extinction, but the new study, which surveyed more than 500 species, uncovered steep losses even among such traditionally abundant birds as robins and sparrows.

There appear to be multiple causes for the steep declines.  The largest ones are likely habitat loss and the wider use of pesticides.  Rachel Carson’s 1962 book Silent Spring warned of the dangers of pesticides and took its title from a world that has lost its birds.

The survey includes 76% of all bird species in the US and Canada, but actually represents almost the entire population of birds.  Grassland species have suffered the biggest declines by far, as a result of modern agriculture and development.  Pesticides, such as neonicotinoids, make it harder for birds to put on weight needed for migration, delaying their travel.

There are a few bright spots:  bald eagles are thriving, and falcon and waterfowl populations are on the upswing.  These are species that have been the subject of conservation measures in recent decades.

Stopping the bird decline will require a great deal of effort to defend habitats, restrict chemicals, and redesign buildings.  Without that effort, birds will continue to disappear.

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Birds Are Vanishing From North America

Photo, posted April 1, 2012, courtesy of Barry Skeates via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bananas In Danger

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For a few years we have been talking about the precarious position of the global banana crop, which is almost entirely based upon a single cloned cultivar known as the Cavendish banana.  The banana you buy in Rome is identical to the one in Rochester.  And therein lies the danger:  if a fungal blight can kill one banana shrub, it can kill them all.

For decades, a fungal disease known as Panama Disease Tropical Race 4 has been wreaking havoc on banana plantations in the Eastern Hemisphere.   Even though it was first identified in Taiwanese soil samples in the early 1990s, the destructive fungus remained confined to Southeast Asia and Australia until it was confirmed in both the Middle East and Africa in 2013.  Experts continued to fear its eventual appearance in Latin America, which is the epicenter of the global banana export industry.

In August, Colombian agricultural authorities announced that laboratory tests have positively identified the presence of Tropical Race 4 in the Caribbean coastal region and declared a national state of emergency.

The infection of the banana plant does not produce bananas that are unsafe for humans.  What happens is that the infected plants eventually stop bearing fruit.

Cavendish bananas are a prime example of the dangers of growing crops with limited genetic diversity – known as monoculture.  It leaves food systems dangerously vulnerable to disease epidemics.

This has happened to the global banana crop before when the predecessor to the Cavendish banana – the Gros Michel – was mostly eradicated by another fungal outbreak.  At the moment, there is no ready replacement banana to bail out the industry, but scientists are desperately trying to breed one.  In the meantime, the world’s supply of bananas is in real danger.

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The banana is one step closer to disappearing

Photo, posted July 9, 2009, courtesy of Dabin Lambert via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Degraded Permafrost In The Arctic

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Permafrost is defined as rock or soil that has been at or below the freezing point of water for two or more years.  Most of it is located in high latitudes in and around the Arctic and Antarctic regions.   Permafrost covers nearly a quarter of the exposed land in the Northern Hemisphere.

Permafrost can contain many different materials including bedrock, sediment, organic matter, water and ice.  Because of the presence of organic matter, permafrost is potentially the source of significant methane emissions if it thaws and the trapped biomass begins to rot.

A recent study looked at the results of 30 years of aerial surveys and extensive ground mapping of an area of Canada’s high Arctic polar desert known as the Eureka Sound Lowlands.  This area has an extremely cold climate and the permafrost there is over 1/3 of a mile thick.  It has long been assumed that this landscape was stable.

Research led by McGill University in Montreal has found that this is not the case.  The increases in summer air temperatures seen in recent years are initiating widespread changes in the landscape.

A particular landform known as a retrogressive thaw slump that forms when ice within permafrost melts and the land slips down is widely occurring in the area.  The absence of vegetation and layers of organic soil in these polar deserts make permafrost in the area particularly vulnerable to increases in summer air temperatures.

The research indicates that despite the cold polar desert conditions that characterize much of the high Arctic, the interaction between ice-rich permafrost systems and climate factors is complex and the links between global warming and permafrost degradation are not well understood.

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Widespread permafrost degradation seen in high Arctic terrain

Photo, posted August 11, 2018, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rapid Antarctic Melting

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The Ross Ice Shelf in Antarctica is the world’s largest ice shelf, covering an area roughly the size of France.  Scientists have spent several years building up a record of how the northwest sector of the enormous ice shelf interacts with the ocean beneath it.  Their results show that the ice is melting much more rapidly than previously thought because of in-flowing warm water.

In general, the stability of ice shelves is thought to be mostly influenced by their exposure to warm deep ocean water.  But the new research has found that surface water heated by the sun also plays a crucial role in melting ice shelves.

The interactions between ice and ocean water that occur hundreds of meters below the surface of ice shelves have a direct impact on long-term sea level.  The Ross Ice Shelf stabilizes the West Antarctic ice sheet by blocking the ice that flows into it from some of the world’s largest glaciers.

When ice shelves collapse, the glaciers that feed them can speed up by a factor of two or three.  None of the collapsing shelves in the past have come anywhere close to the size of the Ross Ice Shelf, which is more than 100 times bigger.

The new study by New Zealand’s National Institute of Water and Atmospheric Research showed that sun-heated surface water flowing into the cavity under the ice shelf near Ross Islands caused melt rates to nearly triple during the summer months.  This indicates that the loss of sea ice resulting from climate change is likely to increase melt rates in the future.  While the Ross Ice Shelf is still considered to be relatively stable, the new findings show that it may be more vulnerable than previously thought.

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Rapid melting of the world’s largest ice shelf linked to solar heat in the ocean

Photo, posted February 15, 2009, courtesy of Alan Light via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Vulnerable Shorelines

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Global climate change is having noticeable effects on the environment. For example, glaciers are shrinking.  Plant and animal ranges are shifting and populations decreasing.  And droughts, floods, and wildfires are becoming more frequent and more intense.  According to the Intergovernmental Panel on Climate Change, the evidence indicates that the net damage costs of climate change are likely to be significant and to increase over time. 

Our coastal shorelines, which are already stressed by human activity, pollution, storms, and invasive species, are one of many areas expected to be further threatened by climate change.  Sea level rise and more intense and frequent storms are expected to erode and inundate coastal ecosystems and eliminate wetlands.  Ocean acidification is also projected to disrupt marine environments. 

But according to scientists at the Massachusetts Institute of Technology, seagrasses could play a key role in protecting these vulnerable shorelines from this onslaught.  The MIT research team demonstrated how the ubiquitous marine plants dissipate wave energy and help protect against erosion, which could help mitigate damage from rising seas. 

Using mathematical modelling and experiments, the MIT researchers were able to quantify for the first time how large and dense a continuous meadow of seagrass must be in order to provide adequate damping of waves in a given setting.  They also found that seagrasses offer significant environmental benefits, including preventing beach erosion, protecting seawalls and coastal structures, improving water quality, and sequestering carbon. 

Submerged aquatic vegetation, including seagrasses, provides an ecosystem service exceeding $4 trillion annually.  Hopefully these findings can help provide useful guidance for seagrass restoration efforts.

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Seagrass’ strong potential for curbing erosion

The Effects of Climate Change

Photo, posted October 13, 2010, courtesy of the NOAA Photo Library via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Global Fisheries

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A Rutgers University-led study published in the journal Science has shown that climate change has taken a toll on many of the world’s fisheries and that over fishing has magnified the problem.

Seafood has become an increasingly important source of nourishment as the global population grows, especially in coastal, developing countries where it provides as much as half of the animal protein eaten.  More than 50 million people worldwide work in the fisheries industry or subsist on fisheries.

Scientists at Rutgers and the National Oceanic and Atmospheric Administration studied the impact of ocean warming on 235 populations of 124 species in 38 ecological regions around the world.  Species included fish, crustaceans such as shrimp, and mollusks such as scallops.  They combined data on fisheries with ocean temperature maps to estimate temperature-driven changes in the sustainable catch over 8 decades.  The data covered about one-third of the global catch.

According to the study, ocean warming has led to an estimated 4.1% drop in sustainable catches, on average around the world, for many species of fish and shellfish from 1930 to 2010.  In five regions that include the East China Sea and the North Sea, the estimated decline was 15 to 35%.

The researchers recommend that fisheries managers eliminate over fishing, rebuild fisheries, and account for climate change in fisheries management decisions.  Over fishing provides a one-two punch to fisheries facing warming waters.   It not only makes fisheries more vulnerable to ocean warming but continued warming will also hinder efforts to rebuild over fished populations.

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Climate Change Shrinks Many Fisheries Globally, Rutgers-Led Study Finds

Photo, posted April 23, 2011, courtesy of Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildlife And The Border Wall

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The border between the United States and Mexico is nearly 2,000 miles long, stretching from San Ysidro, California to Brownsville, Texas.  Discontinuous barriers currently cover approximately 650 miles of our southern border. As the particulars of how to better secure the remaining 1,350 miles of border are worked out, one thing is abundantly clear: extending physical barriers would negatively impact wildlife and the environment.

The Trump Administration has called for a 1,000-mile wall, which would cut across land that includes important habitats for wildlife.  According to an article signed by nearly 3,000 scientists, this plan would “threaten some of the continent’s most biologically diverse regions” by inhibiting species movement and triggering flooding. The paper, which was published in the journal Bioscience, highlights how more than 1,500 native animal and plant species would be affected by the wall, including 62 that are listed as endangered or vulnerable.

An extended border wall would not only impede movement of many wildlife species but it would also put pressure on creatures already in peril, such as the Mexican gray wolf and the Sonoran pronghorn.  Other at risk animals include the ocelot, black bear, and desert bighorn sheep. 

According to researchers, extending the border wall could cause problems for low-flying birds and insects. Even plants, including the endangered wildflower Zapata bladderpod and the threatened whiskerbush cactus, are particularly at risk.

According to a 2011 study, bird-watching and other forms of ecotourism in the Lower Rio Grande Valley brought in more than $344 million in economic activity and approximately 4,400 jobs. 

Preserving our natural heritage must be part of this national security discussion. 

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Nature Divided, Scientists United: US–Mexico Border Wall Threatens Biodiversity and Binational Conservation

Photo, posted December 14, 2014, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saved By The Trees

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The island of Kokota, part of the Zanzibar Archipelago off the coast of Tanzania, is tiny – only one square kilometer and home to just 500 people.  For centuries, its residents subsisted by harvesting the islet’s natural resources, including its trees.

By the early 21st century, the deforestation had become unsustainable and the islanders faced a crisis.  Fisheries were depleted, and rivers ran dry.  The changing climate brought rising sea levels, more erratic rainfall, and coral bleaching in the surrounding waters.  The situation looked hopeless.

But in recent years, the island has come back from the brink of ruin.  Reforestation efforts began in 2008 on the larger island of Pemba and on Kokota itself, led by a Pemba local and a Canadian tree planter who formed the non-profit Community Forests International.  Since then, nearly 2 million trees have been planted on the two islands.  Enthusiastic volunteers on Kokota usually help plant trees during the rainy season, when water is plentiful.

Community Forests International, along with spearheading the tree planting effort, also built Kokota’s first school, and installed rainwater storage tanks for the community.

The conservation group is now devising ways for Kokota to make more money by diversifying its agriculture with crops that grow well in its climate including spices like cloves, cinnamon, and nutmeg.  They are also helping locals to grow more and different vegetables in their gardens.

Small, poor communities are often the most vulnerable to the effects of climate change, such as drought, powerful storms, and depleted fisheries.  Tiny Kokota provides an example of an environmental comeback.  Fighting climate change requires economic solutions along with environmental solutions.  For this one tiny island, it  appears to have been saved by the trees.

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This island was on the brink of disaster. Then, they planted thousands of trees.

Photo, posted July 18, 2015, courtesy of Marco Zanferrari via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Losing Forests Is Felt Far Away

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Large areas of forests in our country are vulnerable to drought, fires and disease.  When forests are heavily damaged, there are well-known local impacts:  drier soils, stronger winds, increased erosion, loss of shade and loss of habitat.

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A Big Problem For The Giant Panda

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The giant panda, a national icon of China, has been the focus of an intensive, high-profile conservation campaign since the 1970s.  In an update to the IUCN’s Red List of Threatened Species last year, the giant panda had its designation changed from “endangered” to “vulnerable” following a nationwide census that revealed its population was improving.  But it appears as though this conservation success may be short-lived. 

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The Doomsday Seed Vault

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The Svalbard Global Seed Vault, tucked away on a Norwegian island far above the Arctic Circle, is often described as humanity’s last hope against extinction after some global crisis and is popularly known as the “Doomsday Vault.”  Although its mission is to keep the world’s seeds safe, it wasn’t actually created to reseed the planet after a world-wide catastrophe.

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Can Cheetahs Survive?

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A new study has revealed that the global population of the world’s fastest land animal – the cheetah – is down to only 7,100, a drop of 50% over the past 40 years.  The dramatic decline in cheetah population could soon lead to the extinction of the species unless urgent conservation efforts are made.

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Pandas No Longer Endangered

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Back in June, we reported that the International Union for the Conservation of Nature was reassessing the giant panda’s status as an endangered species.  Well, in an update of the IUCN’s Red List of Threatened Species in September, the giant panda was indeed downgraded to “vulnerable.”

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Sharks In Hot Water

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The majestic great white shark has been around for a very long time.  Its evolutionary origin dates back 14 to 16 million years.  And while great whites still enjoy decent populations off the coasts of Canada, Australia, and the United States, the same can’t be said for South Africa’s great whites. 

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Size Matters

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One of the crowning achievements for wildlife protection in the US was the establishment of the National Wildlife Refuge system in the 1930s, when the populations of waterfowl were perilously low. Refuges provided breeding and migratory habitat that has allowed a remarkable recovery of many species of ducks and geese.

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