March 29, 2019
Pumas’ Eating Habits Are Ecological Boon
By Noor al-Samarrai/Atlas Obscura
Photo by Erik Kilby/flickr
A male elk can weigh in at 700 pounds or more—over three times the size of a male puma. Yet pumas—also known as mountain lions—are extraordinarily strong and crafty, and can take down large game, such as elk and mule deer, that they can’t possibly eat on their own. We’re not supposed to bite off more than we can chew, but the puma’s habit of doing just that can be an ecological boon. In addition to providing food for scavengers such as bears, foxes, and birds, their leftovers provide a windfall for hundreds of beetle species.

“Most of the focus around mountain lions is typically related to state management objectives,” says Josh Barry, a graduate researcher with  Panthera , a global wildcat conservation organization that conducted a study, led by puma researcher Mark Elbroch, examining the impact of puma hunting habits. Researchers in places such as preserves are typically asked to document the prey killed by the big cats report back to the state management offices. “With this research in particular, Mark thought, why not ask questions while we’re at it, as opposed to just recording the kills,” Barry says.

In previous studies, Elbroch had already documented dozens of large vertebrates—wolves, foxes, black and grizzly bears—that feed on carrion left by pumas. He also grew interested in the insect populations attracted by their kills. The researchers studied a total of 18 elk and mule deer carcasses killed by pumas in Bridger-Teton National Forest in Wyoming, returning weekly over the course of six months from May to October 2016 to check beetle traps and observe how populations shifted over time. 

Would Banning Cigarette Filters Ease Litter?
By Robin Kazmaier/Audubon
Photo by jstanley3/flickr
Shelly Ericksen was handing out supplies for a beach cleanup in San Francisco one morning several years ago when a volunteer said he would pick up only cigarette butts, and wandered off. Ten minutes later he was back, his cupped hands overflowing.

"That kind of turned the lightbulb on in my head," Ericksen says. Now program lead for the San Francisco chapter of Hold Onto Your Butt, a campaign of the environmental nonprofit Surfrider Foundation, Ericksen works to eliminate what she calls the "last socially accepted form of litter." 

In spite of decades of efforts to discourage cigarette butt litter, discarded filters remain the  single most common  item collected in environmental cleanups worldwide, well ahead of plastic bottles and grocery bags. Discarded butts are easily carried by water and wind, often winding up in sewers and then waterways. Ocean Conservancy  reported  that 2.4 million of them were collected in coastal cleanups in 2017 alone.

And while the environmental impacts of items like microbeads and plastic straws have drawn a public outcry and inspired sweeping bans in recent years, cigarette butts remain uniquely stubborn—ever present, and yet seemingly invisible.

Chasing Fish, Fleets Push
to the North
By Emma Bryce/Anthropocene
Photo by Luis Alves/flickr
Some vessels off America’s coast are now fishing 800 kilometers further north than they did some 20 years ago, as warming waters push fish polewards. These extraordinary shifts were revealed in a  new study  that’s among the first to show how climate change influences not only the location of marine species, but also the behaviour of the fishing communities who depend on them.

Looking at the period from 1996 to 2014, the study examined fleets of both large and small vessels that fished off America’s east coast, a region where rapid ocean warming is taking place. It found that large fishing vessels have moved four kilometers north every year since 1996, on average, but some have shifted as far up as 21 kilometers per year to catch northward-moving fish. The researchers even found that certain vessels which had started out fishing off the coast of North Carolina in 1996 were routinely catching their fish from the coast of New Jersey–800 kilometers north–by 2014.

These changes seemed to be heavily determined by how diverse a fleet’s catch was. Larger vessels which caught only one or two species were among those who had to fish the furthest north, to follow the trail of their target species.

How Recreation
is Changing
the Western Economy
Photo by CAJC: in the PNW/flickr
For the past 100 years, Colorado’s Grand Valley rode the wave of commodity prices—from uranium to oil shale to natural gas. Now, the region is staking its survival on another natural resource: the great outdoors.

Flanked by red-rock buttes and the largest mesa in the world, the Grand Valley is capitalizing on its natural assets to bolster its once-flagging economy. Hundreds of miles of bike trails cut across the high desert, vineyards line the banks of the Colorado river, and a white-water rafting park is under development near downtown Grand Junction, the valley’s largest city. More than 1 million tourists flow into the valley every year, many from booming Denver, and unemployment is at the lowest in more than a decade. The region now rivals Moab, Utah, as a premier destination for mountain biking.
“Outdoor recreation could change the face of rural America,” said Sarah Shrader, a local business owner and founder of the Outdoor Recreation Coalition of the Grand Valley. “In four years this place has made a complete turnaround.”

Reelfoot Lake, Ground Zero for Eagle Watching
By Margaret Renkl/The New York Times
Photo by Mick Thompson/flickr
In the far northwest corner of Tennessee lies a landscape like no other. Reelfoot Lake is less a lake than a system of bayous, creeks and swampland connected by areas of shallow open water. It was created in the winter of 1811-1812 when a series of powerful earthquakes and aftershocks caused 15,000 acres of cypress forest to sink. The waters of the Mississippi River rushed into the depression. To eyewitnesses, the river seemed to be flowing backward.

Reelfoot’s average depth is barely more than five feet, and the stumps of hundreds of thousands of drowned trees lie just beneath its surface. Even today, more than 200 years later, it can be unclear where the lake begins and ends. Even the names of its geographical features suggest a porous relationship between land and water: Big Ronaldson Slough. Horse Island Ditch. Buck Basin. Keystone Pocket.

Hundreds of bald eagles surround the lake, perched in bald cypress trees. (That both are “bald” is a coincidence.) Their yellow feet grip the black branches; their fierce yellow eyes are trained on the lake. They are watching for the slippery shadows of fish moving beneath the dark water. They are watching for the splash of a duck landing on the lake.

“The best thing about hunting and fishing,' the Old Man said, 'is that you don't have to actually do it to enjoy it. You can go to bed every night thinking about how much fun you had twenty years ago, and it all comes back clear as moonlight.” 

-Robert Ruark
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