We welcome the opportunity to respond to Sean Noonan’s Viewpoint in last week’s Carletonian about bike use in the Arb.
First, an essential clarification. Mr. Noonan’s article leaves the impression that the Arb is closed to bikes. This is incorrect. The Arb is divided into two sections, the Upper Arb (south of Highway 19) and the Lower Arb (north of Highway 19). Bikes are welcome on trails throughout the Upper Arb, except for some specific trails where bike use is inappropriate. Bikes are not allowed in the Lower Arb.
So the question is not whether bikes should be allowed in the Arb but rather which portions of the Arb should be open to bikes. Mr. Noonan is clearly passionate about biking and we understand that he would like to be able to extend the areas available for bike use. But we also received the opposite advice. We quote a proposal received from a Carleton professor:
“I’m sad to suggest that you close the Upper Arb off to bikes just as you have done with the Lower Arb. It’s always the bad apples that ruin things for everyone. Yesterday at 6:10pm, a racing bicyclist killed a neighborhood cat at the stone bridge near the 2nd St entrance. He was racing down and across the Stone Bridge and up again to 2nd St at 50 mph, hit the cat, and never looked back – despite the obvious impact. I turned as he raced by me and from a distance witnessed the death throes of the cat whom I’d just been petting.”
Some members of the Carleton community want bike use everywhere in the Arb, while others want bikes banned entirely. At this point we are not inclined to follow either suggestion. Here’s why.
Like managers of natural areas everywhere, it is our job to balance competing uses to try to maintain and enhance the Arb for all of its many functions. The Arb has three primary purposes: education, conservation, and recreation. There are times and places when these purposes are not compatible, so different uses are focused in different locations. Recreational uses are given higher priority in the Upper Arb because it is closer to the campus and the rest of Northfield, and has less extensive areas of native habitats. The Lower Arb has a stronger emphasis on education (including class use and scientific research) and conservation, as well as low-impact recreational activities such as running and nature observation. In recent years the Lower Arb has been the focus of extensive ecological restorations, and large areas of prairie and forest are taking shape there. Some recreational uses are restricted in the Lower Arb to be consistent with the maintenance of native ecological communities.
There are a variety of potential conflicts between biking and other uses of the Lower Arb. To choose just one as an example, consider the fact that the Lower Arb is home to two rare and declining species: wood turtles and Henslow’s sparrows. Wood turtles are in trouble throughout their range, and the Arb is one of the few places in Minnesota where wood turtles remain. The turtles are difficult to observe, but we have used radio-telemetry to track them in the Arb. It turns out that they have to cross trails to go between the Cannon River and their nesting grounds. In fact the only way we have found turtles without radios is by spotting them on trails. A bike collision with a turtle crossing a trail could be fatal (see above).
The appearance of Henslow’s sparrows in our prairie restorations in 2005 was one of the Arb’s great conservation successes. This bird is completely dependent on prairie habitat and is declining in most other parts of its range. Henslow’s sparrows nest on the ground, and our birds have been nesting within meters of the Lower Arb’s trails. Sadly not every biker is willing to stay on designated trails, as we have witnessed first hand. A single off-trail biker could destroy a nest, and therefore a season’s reproduction, in seconds.
The maintenance of rare species is one of our top priorities. With the Arb’s populations of both wood turtles and Henslow’s sparrows probably below 10 individuals, the loss of even one animal would be devastating. It is our hope that the Lower Arb will remain a haven for rare species for both education and conservation purposes. So when spring finally arrives, please enjoy riding your bike in the Upper Arb and visit the Lower Arb on foot.