Monday, December 22, 2008

It's pretty much my favorite lagomorph

This started as a run-of-the-mill "critters with which I'm obsessed" post, but that changed this afternoon at a gas station just west of Oconomowoc, when I got a "so much for global warming" lecture while standing at a urinal. This upset me for two reasons: first, the fact that the air temperature in Jefferson County, Wisconsin was hovering around 0°F does not disprove the notion of anthropogenic climate change, and second - and more importantly - I really prefer to be left alone while doing my business.

Anyway, following a family trip to Rocky Mountain National Park many years ago, I left with the perception that the yellow-bellied marmot (Marmota flaviventris, which pretty much literally means "yellow-bellied marmot" in Latin) was pretty awesome. These charismatic sciurids have an entertaining way of lumbering about the talus piles. The American pika (Ochotona princeps), a neighboring rodent seemed lame by comparison. What could they possibly do to be as interesting as marmots?

The answer, unsurprisingly, came from David Attenborough's The Life of Mammals. It turns out that pikas are totally sweet in their own right. First of all, these quarter-pound rodents are compellingly handsome, as shown in the National Park Service photo at left. The ears belie their kinship with rabbits (lagomorphs) rather than ground squirrels (sciurids), as one might otherwise expect.

More importantly, though, their habits are extraordinarily well-suited to the harsh alpine tundra. As Sir David points out, during the short alpine growing season, the pikas "literally make hay while the sun shines" - that is, they gather vegetation, let it dry in the sun, and then hoard it for the winter. But it gets better still: some plants are toxic, so the pikas hoard these plants such that they are available for feeding later in the winter when the toxins have (apparently) decomposed.

Here's where the guest lecture from Professor Urinal comes in: the pika's special adaptations may make it vulnerable to rising temperatures. Noting that pikas are really leftovers from the Pleistocene ice age, researchers at the US Geological Survey [1,2] have found evidence that pikas aren't so much mountain critters as they are cold-weather critters. Apparently, exposure to shade temperatures above 78° F for as little as six hours can be fatal to pikas, "if they are caged on the surface of talus and thus deprived of their behavioral mechanisms to avoid stressful temperatures [1]." 78 degrees! That's when people might unbutton their top buttons, but these little guys freaking die!

For this reason, coverage of the USGS report by The Guardian bore the grim headline "American pika doomed as 'first mammal victim of climate change.'"

The American pika isn't alone: a 2005 study by a Sino-Arizonan team found similar results for the Ili pika (Ochotona iliensis), which is native to the Tian Shan Mountains of China's Xinjiang Uygur Autonomous Region [3].

So, save the pika, and let me pee in peace.

References:
  1. Erik Beever (2002). "Persistence of pikas in two low-elevation national monuments in the western United States." US Geological Survey Forest and Rangeland Ecosystem Science Center, Corvallis, Oregon. Full text retrieved from Yosemite.org.
  2. Erik Beever, Peter Brussard, and Joel Bergera (2005). "Patterns of apparent extirpation among isolated populations of pikas (Ochotona princeps) in the Great Basin." Journal of Mammalogy 84:1.
  3. Li Wei-Dong and Andrew Smith (2005). "Dramatic decline of the threatened Ili pika Ochotona iliensis (Lagomorpha: Ochotonidae) in Xinjiang, China." Oryx 39:1.

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