Air Date: Week of April 5, 2002

A new study suggests that rock climbers may damage the plants growing on cliffs. Guest host Pippin Ross speaks with researcher Michele McMillan.

Transcript

ROSS: A new report says rock climbers have a big impact on the plant life that grows on the cliffs they climb. Michele McMillan is a graduate student at the University of Guelph in Ontario, Canada, who did the research. Michele, how did you figure this all out?

McMILLAN: I actually looked at 25 climbing routes and 25 unclimbed areas. And I would actually tie on at the top of the cliff, and I would lower myself over the edge. And then I would dangle from the rope for, sometimes, hours at a time.

ROSS: And you found?

McMILLAN: Well, I looked at the number of plants that were present in climbed versus unclimbed areas, and I found that much lower numbers were present in climbed areas than in unclimbed areas. And, I also found that there was actually a change in the types of species that were present. So I had 81 percent of all of the plants that I found in climbed areas where alien species to Ontario were only 27 percent of the plants in the unclimbed areas were aliens.

ROSS: So, what does that mean? I mean, how are these non-native species getting in there?

McMILLAN: Well, a couple of things need to happen for the alien species to get into an area. And the one is that there has to be room for them. So, climbers are making room for the alien species simply by reducing the numbers of plants that are present. And then, the second thing that needs to happen is there needs to be some sort of seed or propagule from the plant introduced to the area. And, a good way for that to happen is in the soil on climbers' shoes, or attached to climbers' coats or gear. Or, they can come in on the wind.

ROSS: Now, have you found yourself kind of scowling at climbers?

McMILLAN: Not at all. I want to make it clear that I am not anti-climbing, and I am not anti-climbers at all. I think that climbing can definitely occur in an area with as little impact as possible.

ROSS: And so, that would kind of imply that rock climbers have some responsibility to do what?

McMILLAN: One thing that I suggest rock climbers do is that they stick to currently established climbing routes rather than establishing new routes.

ROSS: Oh, they hate that.

McMILLAN: I know. Climbers do love to be the first one to ascend a climb. But I would ask that climbers just climb where there's already climbing occurring. And there's a couple of other things. There are trees that are hundreds of years old. And some have been found that are over a thousand years old. Obviously, I would ask that climbers don't cut down branches to improve a climb. Another thing that climbers do sometimes, especially when they're establishing a new climb, is that they wire brush or blowtorch mosses and lichens off the rock.

ROSS: No.

McMILLAN: Yeah. It is true. So, I would ask that you just avoid using those finger or toeholds if you find them too slippery, and just try to look for another one.

ROSS: Michelle McMillan is a graduate student at the University of Guelph in Ontario, Canada. Thank you very much, Michelle. And keep up the good work.

McMILLAN: Thank you very much. Take care.

[MUSIC: Neil Diamond "Love On the Rocks"]