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Wildlife crossings

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Every year, there are one to two million collisions between motor vehicles and large animals in the U.S.  About 200 people are killed annually.  Counting smaller vertebrates, around a million animals are killed by vehicles each day.  Research has shown that global warming is triggering widespread species redistribution.  As a result, more and more animals are on the move, changing their habitats to escape warming temperatures and climate extremes.

This situation has created renewed interest in creating wildlife crossings.  These are various kinds of structures that allow animals to traverse human-made barriers like highways.  They include such things as a grassy overpass that allows pronghorn to run across a highway in Wyoming and a long underpass that allows tigers to scamper beneath a highway in India.

In the U.S., there are more than 1,000 wildlife crossings and there are more being built all the time.  Data shows that they are highly effective.  A study of wildlife crossings on Highway 9 through the Blue River Valley in Colorado found that they reduced wildlife-vehicle collisions by nearly 90%. 

Wildlife crossing structures can be expensive to build, costing between $500,000 and $6 million, but research has shown that the money saved by avoiding crashes can recoup these costs in just a few years along with the fact that they potentially save lives.  Federal funding is largely distributed based on areas with the highest number of wildlife-vehicle collisions, which is crucial for addressing public safety issues.  However, a recent study suggests that future proposals need to incorporate climate-driven changes in animal behavior and habitat.

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As Climate Changes Fuels Animal Movement, Will These Structures Still Help Species Cross the Road?

Photo, posted April 5, 2017, courtesy of Jeffrey Beall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Buildings and birds

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Birds face a wide range of dangers.  Billions of them each year face violent deaths.  Concerned individuals point at such things as wind turbines, which in fact do kill hundreds of thousands of birds.  But the great majority of bird deaths are caused by cats.  And that’s a danger that isn’t going to go away.

The second largest cause of bird deaths is collisions with building windows.   Building collisions kill hundreds of millions of birds each year in the U.S. alone.  As other places have seen glass skyscrapers proliferate, such as in Chinese cites, these collisions have become a major global factor in bird mortality.

There are growing efforts across the U.S. and Canada to reduce bird collisions.  Many businesses are taking part in “lights out” programs in which their buildings dim lights during spring and fall migrations.  Some buildings now use special glass that birds can see and avoid.  Some communities even have adopted ordinances that require bird-friendly glass in new construction.  Keeping bird attractants away from windows is another important way to reduce bird strikes.  All these measures have been proven to be effective in reducing the number of bird collisions.

 Companies sell vinyl film with tiny dots that can be affixed to windows.  Both businesses and homeowners have seen substantial reduction in bird collisions with such films installed.

Bird collisions are not a new problem but is one that wasn’t really taken seriously until at least the 1970s.  There isn’t much to be done about the greatest threat to birds – namely cats – but how buildings are constructed and operated is something we can control.

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As Bird Kills from Buildings Mount, Cities Look for Solutions

Photo, posted December 24, 2017, courtesy of Nicolas Vollmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind turbines and bats

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Collisions with wind turbines are one of the leading causes of bat mortality in North America and Europe.  Most bat fatalities are caused by bats colliding with the rotating blades of wind turbines.  Fatalities are highest during autumn migration and on nights with low wind speeds.

According to a recent study, land-based wind turbines kill as many as 880,000 bats a year and are wiping out so many threatened bats that some species may become endangered unless preventative action is taken.

The big challenge is that bat conservation experts and scientists don’t know how to stop or reduce turbine collisions.  They don’t really know why bats are interacting with turbines to the extent that they are.  Do turbines attract bats?  Do turbines’ bright lights or just their silhouettes stimulate an attraction response?

The U.S. Department of Energy has awarded $8 million to five research centers to develop strategies for deterring bats from wind turbines. 

One of these is Bat Conservation International, which is an organization whose mission is to accelerate research to address knowledge gaps in bat ecology and behavior and develop technologies and industry methods to reduce fatality of bats at wind farms.  Among the approaches to be tested is limiting the use of nighttime lighting on wind farms to make migrating bats less likely to fly through blades. 

Another team at Boise State University is designing ultrasonic noisemakers to scare off bats. 

In announcing the new program, the Department of Energy states that wind energy must be appropriately and responsibly sited, which includes the protection of wildlife and their habitats.

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Experts Seek to Spare Bats From Wind Turbine Collisions

Photo, posted January 10, 2013, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking Small-Scale Fishers | Earth Wise

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About half of all global seafood is caught by artisanal fishers.  These are individuals who operate on a small scale – often on a subsistence level – and typically fish only a short distance from shore.  Over 85% of the estimated 2.5 million motorized fishing vessels in the world are less than 12 meters in length.  Compared with large-scale commercial fishing operations, these enterprises are very small.  However, they are essential to the food security and livelihoods of their communities.   Because of their sheer numbers, artisanal fishers are an important sector to monitor, manage, and advocate for.  They may be small-scale, but their importance and impact are huge.

Large ships make use of vessel tracking systems, which were originally conceived to prevent maritime collisions.  Over time, VTS technology has become useful for other purposes including monitoring fishing activity in sensitive marine areas and looking out for forced labor on the high seas.

Among small fishing vessels, only an estimated 0.4% are equipped with VTS technology.  So, a massive number of vessels accounting for a big part of the global catch cannot be monitored.

Researchers at UC Santa Barbara surveyed hundreds of artisanal fishers in Indonesia and Mexico to see if they were willing to pay to participate in a VTS program, or participate for free, or be paid to participate.  Having the equipment would provide multiple benefits to the fishers including increased safety and better fisheries management.  Two-thirds of the survey participants said they were willing to pay for the technology.  The study is the first effort to explore the potential for encouraging wide adoption of VTS technology among artisanal fishers.

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Tracking Small-Scale Fishers

Photo, posted November 30, 2014, courtesy of Bernard Spragg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Shipping And The Endangered Whale Shark | Earth Wise

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Whale sharks are the largest fish in the world.  While they measure up to 60 feet long and weigh up to 15 tons – larger and heavier than a school bus – whale sharks are actually harmless.  They are a graceful, slow-moving, filter-feeding carpet shark.  They are found in marine environments around the world and play an important role in the marine food web and healthy ocean ecosystems.

Whale sharks are an endangered species.  According to the International Union for Conservation of Nature, growing human pressures are putting whale sharks at an increased risk of extinction.  The numbers of these gentle giants have declined by more than 50% over the last 75 years despite many international protections.  Fishing bycatch, poaching, and collisions with ships are the main drivers of the population decline. 

According to new research from marine biologists from the Marine Biological Association and the University of Southampton in the U.K., lethal collisions between whale sharks and large ships are vastly underestimated, and could be the reason why populations are continuing to fall.  Whale sharks spend a large amount of time in surface waters in coastal regions, and the research team theorized that collisions with ships could be causing significant whale shark deaths. 

In the study, researchers tracked the global movements of both ships and whale sharks, and then mapped so-called hotspots where their movements overlapped.  The research team found that more than 90% of whale shark movements fell under the footprint of shipping activity.

While many conservation measures have been taken to protect whale sharks, no international regulations currently exist to protect them from ship collisions.  The researchers say it’s time for that to change. 

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Shipping poses significant threat to the endangered whale shark

Whale sharks (Rhincodon typus)

Global collision-risk hotspots of marine traffic and the world’s largest fish

Photo, posted July 8, 2010, courtesy of Marcel Ekker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Manatees And Pollution | Earth Wise

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Manatees are large, gentle, and curious marine mammals measuring up to 13 feet long and weighing up to 3,300 lbs.  There are three living species of manatees:  The Amazonian Manatee, the West African Manatee, and the West Indian Manatee, which is commonly found in Florida and the Gulf Coast.  Manatees inhabit the shallow, marshy coastal areas and rivers of the Caribbean Sea, the Gulf of Mexico, the Atlantic coast, the Amazon basin, and West Africa. 

The West Indian Manatee, which includes the Florida Manatee, is protected under the Endangered Species Act.  Today, the range-wide population is estimated to be at least 13,000 manatees, with more than 6,500 in the southeastern United States and Puerto Rico.

In Florida, an uptick in nutrient loading from nonpoint sources is triggering algal blooms in Indian River Lagoon and neighboring areas.  These algal blooms have decimated seagrass, manatees’ primary food source. 

As a result , manatees have starved to death by the hundreds along Florida’s east coast.  The state has recorded 974 manatee deaths in 2021, shattering previous annual all-time highs with still approximately two months to go.  Manatees, which need to eat between 100-200 pounds of seagrass daily, are now eating the seagrass roots, which permanently kills the aquatic plants.

Efforts are being made to replant seagrass and to restore clam and oyster beds so that the mollusks can help clean the water.  But manatees face a myriad of additional threats, including collisions with boats and ships, temperature changes, disease, and crocodile predation.

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Florida lawmakers hear Fish & Wildlife agency response to manatee death ‘catastrophe’

West Indian manatee

Preliminary 2021 Manatee Mortality Table by County

Photo, posted May 7, 2010, courtesy of Jim Reid/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Right Whales And The Warming Atlantic | Earth Wise

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The warming of the Atlantic Ocean has driven the critically endangered North Atlantic right whale population from its traditional and protected habitat.  This has exposed the whales to more lethal ship collisions, increased entanglements with commercial fishing gear, and greatly reduced calving rates.

Since 2010, the calving rate has declined, and the right whale population has dropped by an estimated 26%.  Ten years ago, there were about 500 North Atlantic right whales; now there are an estimated 356.

These are some of the best studied whales in the oceans; scientists basically recognize each individual whale and when they are the victims of ship collisions or fishing entanglements, it is easy to identify which animal was killed.

Because of the warming climate, the Atlantic Meridian Overturning Circulation – an important system of surface and deep currents – has slowed down, causing the Gulf Stream to move north.  This has injected warmer and saltier water into the Gulf of Maine.  The warming Gulf of Maine has reduced the abundance of copepods, tiny crustations that are the favorite snack of right whales.   This has reduced whale calving rates and forced the whales to move north to the cooler waters of the Gulf of St. Lawrence.

For the past 6 years, more and more right whales have been observed feeding in the Gulf of St. Lawrence, where there were no protections in place to prevent ship strikes and fishing gear entanglement.  In 2017 alone, 17 right whale deaths were confirmed.

According to a recent report from Cornell University and the University of South Carolina, unless its management is improved, right whale populations will decline and potentially become extinct in the coming decades.

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Warming Atlantic forces whales into new habitats, danger

Photo, posted December 8, 2016, courtesy of Sea to Shore Alliance/NOAA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildlife Bridges

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Highway accidents involving animals are a big problem for both people and animals.  About 200 people die every year in the U.S. as a result of collisions with animals.  In total, one to two million large animals are killed by motorists every year.  And these crashes are expensive:  deer-car collisions cost an average of more than $8,000 each; elk-vehicle collisions about $25,000; and moose-vehicle collisions over $44,000. 

In the United States, there are 21 threatened and endangered species whose very survival is threatened by road mortalities.   These include Key deer in Florida, bighorn sheep in California, and red-bellied turtles in Alabama.

One solution that has been quite effective around the world in reducing car-animal collisions is wildlife overpasses and underpasses.  Crossings and fencing that guide animals over or under highways reduce collisions by 85-95%.

These traffic-spanning bridges and tunnels have been popular in Europe since the 1950s.  The overpasses usually look much like regular overpasses for cars but are decked out with native flora.  The underpasses, which assist shyer and smaller animals, are typically invisible to drivers.

Washington State has recently started building wildlife bridges and underpasses on Interstate 90.  These passes will allow elk, black bears, mountain lions, pika, and even trout to traverse what was once a near-impenetrable barrier of road.

Some animals that are accustomed to human structures start using the crossings almost immediately.  For others, there is learning curve.  As in many things, the early adapters are important as they provide paths and model behavior that more reticent animals learn to follow.

Wildlife bridges are a very good thing for wildlife and for people.

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How wildlife bridges over highways make animals—and people—safer

Photo, posted July 22, 2017, courtesy of David Fulmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

V2V And Safer Cars

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Automated cars are coming, but they face many challenges in sharing the roads with human drivers.  The on-board sensors in these cars are very effective in many ways, but they cannot see around corners or see through buses or trucks.  They won’t know if six cars ahead, someone has slammed on their breaks leading to a chain-reaction collision.  Of course, human drivers have the same problems.

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North Atlantic Right Whales

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North Atlantic right whales are one of the rarest marine mammals in the world.  In fact, according to the National Oceanic and Atmospheric Administration, there are only about 450 of the whales left.  Measuring approximately 50 feet long and weighing close to 100,000 pounds, North Atlantic right whales are now more critically endangered than mountain gorillas, black rhinos, and giant pandas.

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Whale Sharks

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Whale sharks are the largest fish in the sea.  They can grow more than 40 feet in length, weigh up to 47,000 lbs, and have a lifespan of about 70 years.  They can be found cruising in the open waters of tropical oceans.  But despite being enormous, whale sharks are no threat to humans.  The docile beasts, which feed almost exclusively on plankton, have often been referred to as “gentle giants.”

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