09 Jan 2014:
Faced With Sea Ice Loss,
Emperor Penguins Alter Breeding Tactics
Confronted with the loss of sea ice in some parts of Antarctica, four colonies of emperor penguins have come up with an innovative breeding strategy
to adapt to their changing environment. Using satellite images,
an international team of scientists tracked the four colonies from 2008 to 2012. In the first three years, the emperor penguins hatched and incubated eggs in their customary fashion — atop the sea ice that freezes during the Antarctic winter and spring. But in 2011 and 2012, sea ice did not form until a month after the breeding season began. As a result, the emperor penguins, which are the largest penguin species on earth, did something never before witnessed by scientists: They climbed the nearly sheer walls of large, floating ice shelves — huge structures, often hundreds of square miles in extent, that flow from land-based glaciers into the sea. In the region of the four colonies, the ice shelf walls reach as high as 100 feet. The scientists say the altered breeding behavior could demonstrate how ice-dependent emperor penguins may adapt to a warming world.
06 Jan 2014:
China Crushes Six Tons
Of Ivory to Stem Elephant Poaching
In an effort to stem elephant poaching, Chinese authorities have crushed six tons of confiscated ivory
, the first such effort in the country's history. Coordinated by the State Forestry Administration and the General Administration of Customs, the event was widely publicized and aimed at spreading awareness in China of the scale of the global poaching crisis. Conservation
groups consistently name China as a major driver of elephant poaching, as the country's growing middle class has increasingly sought to buy ivory ornaments and ivory-based medicinal therapies, which have no scientific or medical basis. The six tons of ornaments and tusks that were crushed represent only a fraction of China's ivory stockpile, which is probably more than 45 tons, the Wildlife Conservation Society (WCS) estimates. Still, many conservation groups are applauding China's efforts. "This destruction of ivory by China is a symbol of the government's growing responsiveness to the ivory crisis," the WCS said.
31 Dec 2013:
Atlantic Ocean Zooplankton
Are Now Reproducing in Arctic Waters
For the first time, scientists have discovered species of Atlantic Ocean zooplankton reproducing in Arctic waters
. German researchers say the discovery indicates a possible shift in the Arctic zooplankton community as
The amphipod Themisto compressa
the region warms, one that could be detrimental to Arctic birds, fish, and marine mammals. Studying traps that have been suspended for 13 years in the Fram Strait, scientists from the Alfred Wegener Institute found that small species of crustaceans common to the Atlantic are increasingly moving into Arctic waters. The researchers found fertile females as well as individuals at all stages of development, showing that the Atlantic species is reproducing in the frigid waters. The one-centimeter amphipods are smaller than respective Arctic species, meaning that the spread of the Atlantic crustaceans northward could reduce the volume of food available to Arctic predators. The research was published in the journal Marine Ecology Progress Series
Photo Essay: Documenting the Swift
Change Wrought by Global Warming
For 25 years, photographer Peter Essick has traveled the world for National Geographic
magazine, with many of his recent assignments focusing on the causes and consequences of climate change. In a Yale Environment 360
photo essay, we present a gallery of images he took while on assignment in Antarctica, Greenland, and other far-flung locales affected by climate change. View the photo gallery.
09 Dec 2013:
Intensifying Storms Are
Contributing To Ongoing U.S. Wetlands Loss
The U.S. is losing wetlands at a rate of 80,000 acres per year, in part because of intensifying coastal storms and sea level rise, according to a new government study
. From 2004 to 2009, the country lost more than 360,000 acres of freshwater and saltwater wetlands, a decline driven both by traditional factors, such as coastal development, as well as worsening storms and slowly rising seas, the study says. The rate of loss is a signal that government efforts to protect and restore wetlands are failing to keep pace with major environmental changes, experts told The Washington Post
. The most pronounced wetlands losses were along the Gulf of Mexico, where major hurricanes have wreaked havoc on coastal lands. Along the Atlantic coast, a rapid increase in coastal development is funneling stormwater runoff into wetlands that cannot handle it, the study said. The loss rate of 80,000 acres annually represents a 25 percent increase over the rate of wetlands loss during 1998-2004, the last time government agencies examined the problem.
03 Dec 2013:
Microplastic Pollution Harms
Worms at Bottom of Food Chain, Study Finds
As plastic trash accumulates in ocean ecosystems, it may be damaging worms and other sensitive marine life at the bottom of the food chain, scientists report. Two British studies found
that microplastics — tiny remnants, less than 5 mm in diameter, from the breakdown of plastic trash — made seafloor worms eat
Beach sediments churned by a lugworm
less and transferred pollutants from the plastics to the worms. Because they ate less, the worms had less energy to invest in important functions
such as growth, reproduction, and churning sediments, one of their most important roles in the ocean ecosystem. The worms also absorbed harmful chemicals from the debris
, including hydrocarbons, antimicrobials, and flame retardants, researchers said. Lugworms, often called the "earthworms of the sea," are considered an indicator species because they feed on ocean floor sediments. Microplastics have been accumulating in those sediments since the 1960s, and, although each particle is nearly invisible, taken together microplastics are the most abundant form of solid-waste pollution on the planet.
02 Dec 2013:
Poachers Killed 22,000
Elephants in Africa Last Year, Group Says
Poachers slaughtered 22,000 elephants in 27 African countries last year, according to a new report
. Officials with The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and two conservation groups said that 15,000 elephant
Rhett A. Butler/Mongabay
A herd in Namibia
deaths from poaching were officially reported in Africa and that another 7,000 deaths went unreported. Although that number is a slight decrease from the 2011 estimate of 25,000 poaching deaths, CITES officials warn that poaching rates are far too high and could soon lead to local extinctions. Africa, which is currently home to roughly 500,000 elephants, could lose a fifth of its elephant population over the next 10 years, CITES says. "The estimated poaching rate of 7.4 percent in 2012 remains at an unsustainably high level, as it exceeds natural population growth rates (usually no more than 5 percent)," the report says.
29 Nov 2013:
Wide Mangrove Destruction
Is Documented Along Coast of Myanmar
Rapid agricultural expansion destroyed nearly two-thirds of the mangrove forests
in Myanmar’s Ayeyarwady Delta between 1978 and 2011, increasing the region’s vulnerability to cyclones and typhoons, according to a new study. Using remote sensing imagery
and field data, researchers from Myanmar and Singapore said that the dense mangrove cover in the Ayeyarwady Delta declined from 2,623 square kilometers to 1,000 square kilometers in that 33-year period. The main cause was agriculture expansion and the researchers said that if rates of destruction continue at their current pace the delta’s mangroves could be completely deforested by 2026. Reporting in the journal Global Environmental Change
, the scientists said the loss of mangroves in the Ayeyarwady Delta could put the region at greater risk of major storms such as Cyclone Nargis, which killed 138,000 people in Myanmar in 2008. But the researchers said the destruction could be slowed if Myanmar creates coastal protected areas.
26 Nov 2013:
Updated Conservation List
Finds Forest Giraffes on Brink of Extinction
In an updated list released today, the International Union for the Conservation of Nature (IUCN) noted some significant successes and failures in global wildlife
Okapi, or forest giraffe
conservation efforts. A major success story is the leatherback sea turtle
, whose Atlantic population has recovered enough for the species to be considered only vulnerable, rather than critically endangered. The IUCN attributed the leatherback rebound to better protection of nesting beaches and reduced fisheries bycatch. The updated Red List contains more somber news, though, for the blue-tongued forest giraffe
, the national symbol of the Democratic Republic of the Congo. The striped-legged forest giraffe, a species of okapi, is on the brink of extinction due mainly to the long, ongoing civil war in that country, which has led to increased poaching and loss of habitat. The Red List's ranks of threatened species have grown by 352 species since this summer
, Mongabay reports, with roughly 21,000 species now listed as threatened.
Fish 2.0: A Contest Seeks to Foster
A More Sustainable Seafood Industry
Twenty pioneers in the sustainable seafood business climbed a stage at Stanford University in November in an effort to woo the judges at the Fish 2.0 contest
Click to Enlarge
HM Terry Co.
The winning project connects fishermen directly to customers.
with proposals on how to change the way the U.S. catches, distributes, and markets fish. A business competition at heart, Fish 2.0 brought together entrepreneurs and investors to spur innovation in the tradition-bound seafood industry. Competitors's proposals ranged from converting waste at fish processing plants to expanding a Hawaiian network of aquaponic growers, who raise fish and vegetables together in tanks, into the developing world. One proposal aimed to create a data system to track catches in real time, enabling fisheries managers to hold the line on harvests. Contestants headed home with more than $75,000 in prize money. Read more.
19 Nov 2013:
Pollution From Plastic Trash
May Make Tiny Island a Superfund Site
The U.S. Environmental Protection Agency plans to study whether plastic pollution on a small island in the Pacific Ocean is severe enough to warrant listing it as a Superfund clean-up site
. Tern Island, a 25-acre strip of land about 500 miles northwest of the Hawaiian island
Oahu, is home to millions of seabirds, sea turtles, and the endangered Hawaiian monk seal. The U.S.-based Center for Biological Diversity asked the EPA to add the entire Northwestern Hawaiian Islands and parts of the so-called Great Pacific Garbage Patch
to the list of federal Superfund sites due to extreme marine debris pollution, but the agency has only agreed to undertake an environmental study on Tern Island. The island is awash with debris ranging from plastic water bottles and bits of plastic to discarded fishing gear and home appliances. Studies have shown the trash can take a heavy toll on wildlife — seabirds, for example, often ingest bits of plastic after mistaking them for food and eventually die of starvation. The EPA study is the first step of a potentially years-long process to determine if the island qualifies for listing under the 1980 Superfund law.
14 Nov 2013:
U.S. Crushes Six Tons
Of Illegally Trafficked Elephant Ivory
The U.S. Fish and Wildlife Service
(FWS) destroyed six tons of elephant ivory
today that field agents seized over the past 25 years. The U.S. Ivory Crush event, which took place in Denver, Colorado, marked the first time
the FWS has destroyed large quantities of ivory. The move was an attempt to send a clear message that the U.S. will not tolerate illegal ivory trafficking and the toll it's taking on elephant populations in Africa and Asia, the FWS said. Seized ivory is usually kept as evidence for prosecuting traffickers, then later used for education and training, but the FWS had accumulated far more ivory than it needs. The ivory that was crushed included full tusks, carved tusks, jewelry, carvings, and other objects, and came from at least 2,000 poached elephants, the FWS estimates.
13 Nov 2013:
Plastic Debris in Ocean
Has Spawned a 'Plastisphere' of Organisms
The plastic debris that litters the world's oceans has developed its own unique and diverse microbial ecosystem, researchers report. The microscopic community, which scientists dubbed the "plastisphere,"
includes more than 1,000 species of algae, bacteria, microscopic plants, symbiotic microbes, and possibly even pathogens, the researchers say in Environmental Science & Technology
. Some of the plastisphere microbes, many of which had never before been documented, contain genes that could help break down hydrocarbons, indicating the microbes may play a role in degrading the debris, the research shows. Plastic trash is the most abundant type of debris in the ocean, inflicting harm on fish, birds, and marine mammals that are entangled by it or ingest it. Until now, researchers hadn't looked at microbes living on the debris, which make up a sort of artificial "microbial reef," one of the scientists said
Interview: Using Robots to Unlock
Mysteries of CO2 and the Oceans
As climate change accelerates, scientists are focusing on the key role the world’s oceans play in absorbing half the planet’s carbon dioxide. But the precise mechanisms
Robotic Wave Glider
by which the oceans remove carbon from the atmosphere and the consequences for marine life remain poorly understood. That has led Tracy Villareal, a professor of marine science at the University of Texas at Austin, to devote his research to diatom phytoplankton. To better understand how these tiny organisms mitigate climate change, Villareal has become a pioneer in the use of a wave- and solar-powered ocean-going robot, known as the Wave Glider. In an interview with Yale Environment 360
, Villareal discusses why unlocking the secrets of diatoms is critical to understanding climate change and how deploying robots will revolutionize marine science. “There are all sorts of wild robotic systems under development,” he says. Read the interview.
06 Nov 2013:
Disturbed Tropical Forests
Are Slow to Regain Plant Biodiversity
In tropical forests that are regrowing after major disturbances, the ability to store carbon recovers more quickly than plant biodiversity, researchers from the U.K. have found
. However, even after 80 years, recovering forests store less carbon than old-growth
A regrowing tropical forest in Brazil
forests, according to a study published in the Proceedings of the Royal Society B.
This is likely because regenerating forests are often dominated by small, fast-growing trees and it may take centuries for larger trees, which hold more carbon, to become established, according to scientists from the Center for Ecology & Hydrology and Bournemouth University, who studied more than 600 recovering tropical forests. Tree species that are hallmarks of old-growth forests were rare or missing in the regrowing forests, the study showed. Since regenerating forests are often located far from old-growth forests and surrounded by farmland, it may be difficult for animals to move seeds between the forests, which may account for the lower plant biodiversity, researchers said.
23 Oct 2013:
Endangered Asiatic Cheetahs
Are Spotted by Iranian Conservationists
Iranian conservationists have spotted a rare Asiatic cheetah with four cubs, offering hope that the large cats can be pulled back from the brink of extinction. Only 40 to 70 Asiatic cheetahs exist today, all in Iran. Over the
weekend, conservationists with the Persian Wildlife Heritage Foundation (PWHF) spotted the five cheetahs in Khar Turan national park in northern Iran. "In the past year or so that we closely monitored Turan, we never spotted a family, especially female cheetahs with cubs," Delaram Ashayeri, project manager at PWHF, told the Guardian
. "It shows Asiatic cheetahs are surviving, breeding cubs are managing to continue life. It's good news against a barrage of bad news about these animals." Iranian conservationists have been involved in a decade-long campaign to protect the cheetahs and educate indigenous people living near them. But sanctions imposed by Western nations over Iran's nuclear program have hampered these efforts, making it difficult to secure international funding and equipment, such as camera traps.
17 Oct 2013:
Animals May Play Significant
Role in Carbon Cycling, Researchers Say
Wildlife may play a more important role in the global carbon cycle than researchers have previously given it credit for, according to a study
from an international group of scientists. Although models generally include
Muskoxen in Alaska
carbon cycling by plants and microbes, they often ignore the ways animals contribute to the process. That's a mistake, says Oswald Schmitz, an ecologist at Yale who led the study, because the actions of wildlife can affect carbon cycling through "indirect multiplier effects." For example, the massive loss of trees in North America triggered by the pine beetle outbreak has caused a net carbon change on scale with British Columbia's current fossil fuel emissions, the researchers reported in Ecosystems
. And in the Arctic, where about 500 gigatons of carbon is stored in permafrost, large grazing mammals like caribou and muskoxen can help maintain the grasslands that have a high albedo and thus reflect more solar energy. "We're not saying that managing animals will offset these carbon emissions," Schmitz said. "What we're trying to say is the numbers are of a scale where it is worthwhile to start thinking about how animals could be managed to accomplish that."
11 Oct 2013:
Agricultural Ammonia Emissions
Threatening U.S. National Parks, Study Finds
Ammonia emissions from agricultural fertilizers are threatening sensitive ecosystems in U.S. national parks, a study led by Harvard researchers
has found. Thirty-eight national parks are seeing nitrogen deposition levels at or above the threshold for ecological damage,
Great Smoky Mountains N.P.
the study says. In natural ecosystems, excess nitrogen can disrupt nutrient cycling in soil
, cause algal overgrowth, and make aquatic environments acidic. While some of that nitrogen comes in the form of nitrogen oxides (NOx) from power plants and vehicle exhaust, existing air quality regulations and new clean energy technologies are helping reduce NOx emissions. Ammonia emissions from agricultural operations, however, are expected to climb as demand for food and biofuels surges. Daniel Jacob, who led the study, said that because ammonia is volatile, only 10 percent of the nitrogen makes it into the food, with much of it escaping through the atmosphere and being deposited across the landscape. According to the report, published in Atmospheric Chemistry and Physics
, hardwood trees, such as those shown above, are most sensitive to excess nitrogen in eastern temperate forests, while in western national parks lichens appear to suffer first.
07 Oct 2013:
Nutrient Recycling by Sponges
Is Vital in Sustaining Reefs, Study Says
Sponges are the unsung heroes of coral reefs, helping the vibrant ecosystems thrive in the marine equivalent of a desert, a Dutch team working in the Caribbean has found
. Scientists had long questioned how reefs, some
of the most productive communities on earth, were able to survive in low-nutrient tropical seas. Bacteria help recycle some nutrients, but the so-called "microbial loop" can't account for the high rates of carbon, nitrogen, and phosphorous recycling needed to maintain a coral reef, researchers say. Sponges fill that void by drawing in plankton and organic matter expelled by the corals and shedding cells that other reef organisms ingest as food, the researchers report in Science
. The "sponge loop," as the Dutch team calls the process, recycles 10 times more organic material than bacteria do and produces as many nutrients as all other primary producers in a coral reef combined, they say.
01 Oct 2013:
Small Rainforest Predators
Are Photographed and Studied in Gabon
The west African country of Gabon is known for its gorillas, elephants, and other large animal species, but a recent study
has shed light on little-known rainforest predators that could face increasing pressure from the
bushmeat trade. Using camera traps, bushmeat surveys, and DNA analyses, researchers from Panthera, the Wildlife Conservation Society, and other groups completed the first-ever survey of 12 small carnivore species throughout the country. The study found two species — the common slender mongoose and the Cameroon cusimanse — that hadn't been found in Gabon before, and it documented an extended range for the Egyptian mongoose. “It appears that these species are widespread and not currently threatened, but the proximity of many small carnivores to human settlements and the growing bushmeat trade could potentially impact these populations," said Wildlife Conservation Society researcher Fiona Maisels, who co-authored the study. "These new findings will help inform future management."
26 Sep 2013:
Major Initiative Announced
To Help Curb Elephant Poaching in Africa
The Clinton Global Initiative and 16 conservation organizations have announced that they are investing $80 million
over three years to stem the epidemic of elephant poaching in Africa, which has surged recently due to increasing demand for ivory in Asia. The Partnership to Save Africa's Elephants, which includes the governments of seven African nations, will fund programs that scale up anti-poaching enforcement, combat trafficking at ports and markets with more enforcement and harsher penalties, and curb the demand for illegal ivory with ad campaigns aimed at consumers in China, Vietnam, and other nations. "We cannot hope to reverse the dramatic decline in elephant populations without addressing all three parts of the problem," said Patrick Bergin, CEO of the African Wildlife Foundation.
25 Sep 2013:
More Than 80 Elephants Dead
From Cyanide Poisoning in Zimbabwe Park
Poachers poisoned watering holes with cyanide in Zimbabwe's Hwange National Park, killing 81 elephants
in the latest wave of slayings to supply the trade in illegal ivory. The cyanide, poured into remote watering
Hwange National Park
holes in the park, also killed smaller animals and vultures that ate the poisoned carcasses. Park rangers arrested nine alleged poachers after following them to a cache of ivory tusks hidden in the park. The elephant death toll of 81 includes 41 carcasses found earlier this month following another cyanide poisoning incident in Hwange park. Zimbabwe's new environment minister, Saviour Kasukuwere, has pledged to make jail penalties for poachers harsher. Elephant and rhino poaching in Africa
has accelerated in recent years due to increasing Asian demand for ivory and rhino horn, which is used in traditional medicines, even though it has no proven medicinal properties. Officials estimate tens of thousands of elephants are being slaughtered each year in the worst wave of poaching in decades.
12 Sep 2013:
Migration of Trees Is
Not Keeping Pace with Warming
Most tree species in the U.S. aren't migrating northward as rapidly as predicted in response to climate change, a new study says
. Looking at 65 species across
Kilmer Forest, North Carolina
31 eastern states, the team found no consistent, northward migration of tree species, as many other climate studies have predicted. Rather than shifting northward by dispersing seeds to cooler climates, the researchers found, tree species are responding by speeding up their life cycles. "Most trees are responding through faster turnover," says lead scientist James Clark
of Duke University, "meaning they are staying in place but speeding up their life cycles in response to longer growing seasons and higher temperatures." The results appear in Global Change Biology
Counterpoint: Two Scientists Offer
A Dissenting View on Ascension Island
Ecologists Daniel Simberloff, of the University of Tennessee, and Donald Strong, of the University of California, Davis, have written a critical appraisal of a recent Yale Environment 360
article by Fred Pearce about Ascension Island. In their critique, the two scientists contend that Pearce failed to accurately describe what has occurred on the island and misrepresented the science of restoration ecology. Read more
03 Sep 2013:
Crop Pests Migrate Poleward
Due to Global Warming, Study Says
Global warming has been driving crop pests toward the North and South poles at a rate of 1.7 miles per year, according to new research from the U.K. Looking at the
Stem rust (Puccinia graminis fungus)
distribution of 612 crop pests over the past 50 years, the researchers found a strong correlation between warming global temperatures and increased ranges for the pests. “If crop pests continue to march polewards as the Earth warms, the combined effects of a growing world population and the increased loss of crops to pests will pose a serious threat to global food security,” said Daniel Bebber, a biologist at the University of Exeter who led the study published in Nature Climate Change
. Crop pests — which include insects as well as bacteria, fungi, viruses, and nematodes — destroy 10 to 16 percent of the world's crops each year, or enough food to feed nine percent of the population, scientists estimate.
27 Aug 2013:
Mexican Gray Wolves
Granted Increased Protection in the U.S.
The U.S. government has agreed to expand the territory
where a small population of Mexican gray wolves in the southwestern U.S. can be protected and reintroduced.
Mexican gray wolf
Under a pair of agreements with the non-profit Center for Biological Diversity, the U.S. Fish & Wildlife Service also has consented to a plan under which Mexican gray wolves that cross the U.S.-Mexico border and establish territories in Arizona and New Mexico will no longer be captured by U.S. authorities. The agency will also start releasing captive Mexican gray wolves into Gila National Forest and allow them to establish territories throughout much of New Mexico and Arizona. That rule, set to be finalized by January 2015, significantly expands the habitat for a beleaguered population of about 75 Mexican gray wolves
in those states. Wildlife ecologists have been advocating for such measures, saying increased protections and expanded territories are essential to the recovery of the Mexican wolf population, but states in the region have strongly opposed such an expansion.
21 Aug 2013:
Thai Monkeys May Abandon
Stone Tools Due to Human Disruptions
Human disturbances in Thailand’s Laem Son National Park may be causing Burmese long-tailed macaques to abandon their use of stone tools, say researchers studying the primates
. The only monkeys in Asia to use
stone tools — and one of only three non-human primates worldwide to do so — these Burmese macaques have learned to use coastal rocks to crack the hard-shelled crabs, snails, and oysters that make up their diet. Habitat loss to rubber and oil palm farming, competition with humans for food sources, and threats from domestic dogs are forcing the macaques to change their foraging habits, researchers from Singapore’s Nanyang Technological University report. The monkeys are also showing signs of acclimating to humans and becoming dependent on human food sources.
20 Aug 2013:
Google ‘Street View’ Will
Document Changes to World's Coral Reefs
Marine biologists are teaming up with Google to photograph detailed 360-degree panoramas of coral reefs around the globe. Using technology similar to
Google’s Street View feature, users will be able to survey coral reefs much like they might scope out a city block. The project, Google Street View Oceans
, has already surveyed a 150-kilometer stretch of the Great Barrier Reef and is now working on reefs in the Caribbean
. "Only 1 percent of humanity has ever dived on a coral reef, and by making the experience easily accessible the survey will help alert millions of people around the world to the plight of coral reefs," said Ove Hoegh-Guldberg, a marine biologist at the University of Queensland in Australia who is leading the survey. Image recognition software will log the distribution and abundance of marine organisms, and the researchers hope "citizen scientists" viewing the reefs will help assess other key measures of reef health.
15 Aug 2013:
Plants in U.S. Southwest
Moving Higher as the Climate Warms
Numerous plant species on a mountain in the southwestern U.S. are migrating to higher elevations
as the climate gets warmer and drier, according to a new
University of Arizona
An alligator juniper on Mount Lemmon
study. After comparing the results of a recent survey of 27 plants found on Mount Lemmon, a 9,157-foot peak near Tucson, Ariz., with a similar survey conducted in 1963, researchers at the University of Arizona found that three-quarters of the plants have shifted their range “significantly” upslope in the last five decades. In some cases, researchers found that the plants had moved upward by as much as 1,000 feet, into a much narrower elevation range than where the plants existed in the early 1960s. Writing in the journal Ecology and Evolution
, the researchers note that the lowermost boundary for 15 of the species has shifted upslope.
14 Aug 2013:
Bears Using Wildlife Corridors
In Canadian Park, Genetic Tests Show
Genetic testing has revealed that bears in Canada’s Banff National Park routinely cross the bridges and underpasses along the Trans-Canada Highway
, evidence that the ecological corridors provide safe
A grizzly passes through a Banff underpass
passage along a busy roadway that otherwise threatens to fragment wildlife habitat
. Using 420 wire snag “hair traps” and 497 rub trees at 20 crossings to collect hair from passing bears, researchers from Montana State University determined that 15 individual grizzly bears and 17 individual black bears used the passages over a three-year period. According to researchers, those accounted for about 20 percent of the park’s bear populations, suggesting the passageways are providing enough connectivity to maintain a healthy ecosystem for bears and other large mammals. Twenty-five passages were installed in the 1990s
when the government widened a highway that includes a 100-mile stretch bisecting Banff.