Week of 2/15/2009

Dear EarthTalk: What"s happening with wild populations of cheetahs, the fastest land animals on Earth?

—Eduardo Ramirez, Braintree, MA

Due to its plight in recent decades, the cheetah, which can reach speeds of 70 miles per hour, is considered one of the world"s most endangered species by the Convention of International Trade in Endangered Species (CITES).

A hundred years ago some 100,000 wild cheetahs inhabited 44 or more countries throughout Africa and Asia. According to the Cheetah Conservation Fund (CCF), a Namibia-based non-profit organization, today the species exists in only two dozen of those countries—including areas of North Africa, the Sahel, East Africa and southern Africa—with worldwide population numbers now between 12,000 and 15,000 individuals living in small groups. In addition, about 150-200 of the fast cats live in the wild in Iran (where they are known as the Asiatic Cheetah), their forebears having been brought in from Africa in the early 20th century.

The chief threats to the cheetah"s existence are loss of habitat, poaching and hunting (their hide and trophies can command top dollar), and getting shot by livestock farmers. Decline of gazelles, wildebeests, impalas and other preferred prey species (also due to hunting and habitat loss) is a factor, too.

A cheetah mother and her cub on the Masai Mara National Reserve in Kenya.© Getty Images

According to CCF, throughout Africa cheetah numbers are dwindling even within protected wildlife reserves due to increased competition from other larger predators like lions and hyenas. As a result, most protected areas are unable to maintain viable cheetah populations, so individual cats tend to fan out beyond wildlife reserves, placing them in greater danger of conflict with humans. Those cheetahs that do survive in the wild come from a smaller, less diverse gene pool, leaving them susceptible to disease and predation in their own right. Furthermore, captive breeding has proven tricky, and wildlife biologists are not optimistic that such efforts can have a measurable positive impact on the cheetah"s future.

Cheetahs have lean bodies, long legs, a large heart and expansive lungs. And with these features come additional speed; perhaps this is why the cheetah is often referred to as the "greyhound" of the cats. In fact, some say a cheetah looks like a "dog with a cat"s head." But with weaker jaws and smaller teeth than other large predators, cheetahs have difficulty protecting their kills, let alone their own cubs. This has meant that population numbers for wild cheetahs are falling faster than for other big cats.

The cheetah"s future may look dim, but conservationists have been working to lessen the decline in some areas. For instance, CCF began educating livestock farmers around Namibia in the early 1990s about how to prevent cheetahs from preying on their livestock without resorting to the rifle. As a result of these education efforts, along with stronger enforcement of endangered species and anti-poaching laws, cheetah populations in that country stabilized—now some 2,500-3,000 cheetahs make their home in Namibia—after having fallen to half that the previous decade. Clearly more such efforts are needed.

CONTACTS: Cheetah Conservation Fund; Convention of International Trade in Endangered Species (CITES).

Dear EarthTalk: Don"t all these huge snow and ice storms across the country mean that the globe isn"t really warming? I’ve never seen such a winter!

—Mark Franklin, Helena, MT

More extreme weather events —- from snowstorms to hurricanes to droughts -— are likely side effects of a climate in transition, but most scientists maintain that any year-to-year variation in weather cannot be linked directly to either a warming or cooling climate.© Getty Images

On the surface it certainly can appear that way. But just because some of us are suffering through a particularly cold and snowy winter doesn"t refute the fact that the globe is warming as we continue to pump carbon dioxide and other greenhouse gases into the atmosphere.

According to the National Aeronautics and Space Administration (NASA), the 10 warmest years on record have occurred since 1997. And the National Atmospheric and Oceanographic Administration (NOAA) reports that recent decades have been the warmest since at least around 1000 AD, and that the warming we"ve seen since the late 19th century is unprecedented over the last 1,000 years.

"You can"t tell much about the climate or where it"s headed by focusing on a particularly frigid day, or season, or year, even," writes Eoin O"Carroll of the Christian Science Monitor. "It"s all in the long-term trends," concurs Dr. Gavin Schmidt, a climatologist at NASA"s Goddard Institute for Space Studies.

Most scientists agree that we need to differentiate between weather and climate. The NOAA defines climate as the average of weather over at least a 30-year period. So periodic aberrations—like the harsh winter storms ravaging the Southeast and other parts of the country this winter—do not call the science of human-induced global warming into question.

The flip side of the question, of course, is whether global warming is at least in part to blame for especially harsh winter weather. As we pointed out in a recent EarthTalk column, warmer temperatures in the winter of 2006 caused Lake Erie to not freeze for the first time in its history. This actually led to increased snowfalls because more evaporating water from the lake was available for precipitation.

But while more extreme weather events of all kinds—from snowstorms to hurricanes to droughts—are likely side effects of a climate in transition, most scientists maintain that any year-to-year variation in weather cannot be linked directly to either a warming or cooling climate.

Even most global warming skeptics agree that a specific cold snap or freak storm doesn"t have any bearing on whether or not the climate problem is real. One such skeptic, Jimmy Hogan of the Rational Environmentalist website writes, "If we are throwing out anecdotal evidence that refutes global warming we must at the same time throw out anecdotal evidence that supports it." He cites environmental groups holding up Hurricane Katrina as proof of global warming as one example of the latter.

If nothing else, we should all keep in mind that every time we turn up the thermostat this winter to combat the cold, we are contributing to global warming by consuming more fossil fuel power. Until we can shift our economy over to greener energy sources, global warming will be a problem, regardless of how warm or cold it is outside.