Here’s a statistic you may not have run across before checking The Gist today: the number of turtles farmed each year in China. A new survey of China’s 1,499 registered turtle farms says that number is at least 300 million and could easily top 600 million. The reported trade is more than 100,000 metric tons per year, worth $750 million.
The news strikes me as a wake-up about the collective appetites of humans on our planet. I’ve been dimly aware that turtles were edible since about 1991, when I happened on an Alabama farmer picking up a freshly killed snapping turtle by the tail from a rural road. I know there are campaigns to save sea turtles from the pot in Baja California, and turtles are often on the menu (and in the pharmacy) in Asia. But 100,000 tons - roughly two Titanics’ worth - per year?
The study’s authors took a novel approach to compile these numbers: they just asked. They sent questionnaires to the 1,499 farms and got answers from just under half (the authors made follow-up visits to a few farms to gauge the accuracy of responses.) That’s why the bottom line is at least 300 million turtles worth $750 million - half the farms didn’t respond, and other, unregistered farms almost certainly operate off the books.
The news sends mixed messages: on the one hand, at least those hundreds of millions of turtles aren’t being plucked, slow legs waving, from the muddy banks of Chinese wetlands. People have long noted the enormous numbers of turtles in Asian markets, and until now the assumption has been they were mostly coming from the wild.
On the other hand, farming carries its own problems. Among the top 11 species reported from turtle farms, seven are listed endangered or critically endangered on the IUCN Red List. Also in the stock ponds are non-native species from as far away as the U.S. (including the alligator snapping turtle of the deep South, a Thanksgiving-sized turtle if there ever was one). Escapes are inevitable on farms, even for turtles. Escaped, often inbred, native species can harm local gene pools (as with farmed salmon), whereas non-native escapes can become invasive (see Burmese pythons in the Everglades).
Check this New York Times article for more on the plight of Chinese turtles and on conservation in the rapidly developing country in general. Meanwhile, if you’ve managed to picture this news as a teetering mountain of turtle carcasses, you’re ready for the next statistic: The USDA reports that on average, each American eats 51 pounds of pork per year. And that’s third behind beef and chicken.
Politicians, journalists, even scientists love to talk about the “promise of biofuels.” But a thorough news feature in last week’s Nature reveals just how empty that promise may be.
Shown above is a Midwestern plant in which corn starch is turned into ethanol. Global ethanol production hit 13.2 billion gallons in 2007, more than double the production four years before. In the U.S., almost a quarter of all corn production now goes toward making ethanol. But, as Jeff Tollefson points out in the Nature piece, the agricultural techniques used for ethanol’s production “often damage the environment on a scale that far outweighs any good achieved through the biofuels’ use.”
Enter “second-generation” biofuels made from trees and grasses, which are cheaper and most sustainable raw materials than corn. A big push in the industry right now, according to Tollefson, is turning cellulose (from the cell walls of plants) into fuel. But there’s a big catch to that approach, too:
The fly in this ointment is that the world cannot yet boast a single commercial-scale cellulosic-ethanol facility. Breaking cellulose down into sugars is not easy work, and can use up a lot of energy; what’s more, not all the sugars produced are easily fermented.
Even if bioengineers successfully tinkered with those chemical processes, and even if they created a crop that could be an ample source of the cellulose, they’d still need to figure out how it could could all be done on a large scale. With all of the roadblocks, Tollefson argues that biofuels “will never take over the whole liquid-fuel market, let alone amount to a large proportion of total energy use.”
The best option, he concludes, would be to increase our fuel efficiency:
In the same law that expanded the ethanol mandate, Congress also increased the fuel-efficiency requirements for vehicles by 40%…And as Ingram points out, âIf we increase gas mileage by 1 mile per gallon, that is about equal to all the ethanol we are making right now from corn.â?
If you live in southern Florida, Burmese pythons might have already settled into your backyard. These invasive species (see Ecocenter: The Land for more about invasive species) are naturally found in Asia but a population took root in Everglades National Park before 2003—probably pets that were released (or escaped) into the wild—and they are now spreading throughout the region.
Where the snakes end up is limited, though, by the availability of suitable food, shelter and climate. Thatâs good news for people living in the north; itâs too cold for the snakes. At least for now.
Scientists at the U.S. Geological Survey have mapped out the range of suitable climate for the pythons at present (above) and at the end of the century, after decades of global warming (below). The bad news is that the changing climate could open up new areas to the snakes. Maybe even where you live.
The Burmese python is a scary creature. Anything that would take on an American alligator would be (below, a snake fighting an alligator in Everglades National Park). But what dangers does their spread actually hold?
Bob Reed, a USGS wildlife biologist who helped develop the maps, said in a statement that âwildlife managers are concerned that these snakes, which can grow to over 20 feet long and more than 250 pounds, pose a danger to state- and federally listed threatened and endangered species as well as to humans.â? Furthermore, he said, âSeveral endangered species have already been found in the snakes’ stomachs. Pythons could have even more significant environmental and economic consequences if they were to spread from Florida to other states.â?
Take a drive through a western state some evening, when the light slants down over the sagebrush, and watch for jackrabbits. Whether they’re sitting motionless, TV-antenna ears pricked, or loping down the dusty roadsides, they’re part and parcel of the wide open spaces.
So it’s staggering to learn that white-tailed jackrabbits have all but vanished from two of our iconic western parks: Yellowstone and Grand Teton. Together, these two parks are a riot of wildlife at the center of the vast Greater Yellowstone Ecosystem, which stretches 20,000 square miles across Wyoming and adjacent Idaho and Montana.
Mysteriously, the hares just faded away, unnoticed, sometime in the middle of the last century - under the noses of sightseeing tourists and eagle-eyed field biologists. You can kind of imagine how the world could lose an earwig species, perhaps, or maybe a fungus beetle, while it wasn’t looking. But a large, cute mammal so abundant it was once made into coats? Even stranger, jackrabbits are still numerous - and hunted - in other parts of their range.
Ecologist Joel Berger reported the vanishing act after studying 130 years of historical records, museum databases, reports from field biologists, and analyses of an enormous number of coyote droppings. Berger’s research (the paper is not yet online) turned up only one jackrabbit sighting in Yellowstone since 1990 and five in Grand Teton and Jackson Hole since 1978, according to his paper. Reports from the 1920s and 1930s pegged the hares as fairly common, and then the sightings ceased. Coyote scat told the same story: droppings contained 10 percent hare hair in the 1930s, 1 percent by the 1970s, and none by the late 1990s.
The tourists that flock to these parks each summer tend to point their cameras at bigger animals. But big game like pronghorn, bison, elk, and moose could feel repercussions from a dearth of jackrabbits, Berger suggested. With fewer rabbity morsels to prey on, coyotes could well turn to the young of larger animals, as has already been noted in parts of Montana, Wyoming, and South Dakota, according to the paper.
Perhaps more worrying is what the disappearance says about our ability to judge how well conservation is working. If species disappear without our knowledge, we run up against the problem of a shifting baseline. It’s a form of blissful ignorance: Only by having a complete record of the past can we judge how much the world of the present is changing (for more on shifting baselines, see the blog of the same name).
As for white-tailed jackrabbits, they’re far from extinct at the moment. Berger advocates reintroducing them to Yellowstone and Grand Teton, both to restore the ecosystem and to allow us to witness the ways these (nearly) pristine places change as jackrabbits return. We might learn something new. But it won’t be a matter of simply pulling them out of a hat.
A couple of weeks ago, I wrote about the eco-friendly Masdar City, in the Persian Gulf, which will run largely on solar power. When he wrote about the city, NYT columnist Andrew Revkin lamented that such a thing wasn’t happening in the Southwestern U.S. But maybe California is headed that way.
In the last six years, the amount of photovoltaic-produced power used by Californians has grown by 17 times, according to the California Energy Commission. At the same time, the average photovoltaic system size has decreased, indicating more and more cases of residential (versus large commercial) use.
The clever folks at Cooler Planet found an interesting way to play with the data:
Rather than reading over data and spreadsheets, we thought it would be interesting to create an interactive heat map that depicts the concentration of solar installations (number of systems, total watts, average system size, and carbon emissions) in California and the progress solar has made over the last decade.
Above is a screenshot of their map, showing (in teal) all of the solar installations in California since 2002.