FIDOS Comments at October 11, 2006 Open Space Board of Trustees Meeting

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I carefully read Mr. Lenth’s study when I heard that it had been relied on by the County Commissioners last spring to justify the continued exclusion of dogs from Hall and Heil ranches. I also attended the Boulder County Nature Association symposium on invasive species on April 17th where Ben was a presenter. I was disappointed that Mr. Lenth started that presentation with a dramatic slide showing a mountain lion on a precipitous rock outcropping cornered by hunting dogs. While it was an attention grabber, it really illustrated nothing other than the fact that humans have used dogs to track and hunt Pumas. What was not shown in that slide was the person taking that picture, and the less sensational fact that humans have--largely with guns but also with relentless development--pushed the big cats out of much of their traditional habitat, especially in the Eastern US.

Mr. Lenth’s paper points out that dogs are related to wolves and are therefore hunters–although not very good ones. He spends several pages referencing literature on dogs from around the world–and much of it from the "third world"--which establishes that feral dogs or domestic dogs running wild have the capacity to do harm to other animals. While some of this is interesting–such as the fact that a dog would eat a wombat in Australia or an iguana in the Gallapagos, or that a pack of "black squirrels" actually killed a dog in Russia–none of it is really remarkable, nor relevant to the issue of whether dog owners should be able to recreate with the family pet on Boulder Open Space.

The real focus of Mr. Lenth’s study is to determine what, if any, effect the presence of dogs on a trail corridor might have on the presence of other mammals. To that end Lenth used a combination of remote cameras, track plates, pellet plots, and scat surveys to look at trails in Hall and Heil ranches where dogs are not permitted to compare them to sections of trail in Boulder Mountain Park. Although I was hiking many of these trails on a daily basis long before Mr. Lenth was born and have made many of my own observations about animal behavior, I am not a natural scientist nor a statistician. It is not my purpose to question whether Mr. Lenth’s methods of study were scientifically appropriate, or whether his conclusions are supported by the evidence. It is also not my purpose to question whether a comparison between open space which abuts a city the size of Boulder and gets several million visitors a year versus open space in a relatively remote setting many miles from here is a fair comparison. Nor is it my purpose to look for other explanations for what Mr. Lenth observes and the conclusions he draws from those observations. Instead, I want to look at what Mr. Lenth’s study apparently demonstrated to HIS satisfaction:

First, that mule deer tend to move away from trails that people use for recreation–regardless of whether dogs are also allowed on those trails. Where dogs are NOT allowed "deer activity was decreased within 50 m of trails." Where dogs are allowed, "deer activity was decreased within 100 m trails."

Second, that small mammals such as squirrels, rabbits, chipmunks, and mice also show decreased activity close to trails where dogs are allowed, "though these species’ activity resumes normal levels within 50 m from trails..."

Third, that there was a greater incidence of prairie dog burrows within 25 m and 10 m of trails where dogs were not present than where dogs were allowed, although the presence of dogs did not significantly affect presence of prairie dog burrows within 50 m of such trails.

Fourth, that "native carnivore" show increased activity along trails that permit dogs as opposed to trails where dogs are not permitted. This finding was particularly true of the red fox; although bobcats were the exception to this finding, as measures of bobcat activity decreased on the trails that allowed dogs.

There is not a single word in this study addressing the following question:

Assuming that the presence of dogs on some trail corridors tends to decrease the activity of certain mammals within 25, 50, or even 100 m of the trail, DOES THAT FACT HAVE ANY IMPACT AT ALL ON THE ABILITY OF THOSE SPECIES TO FEED, BREED, SURVIVE, AND THRIVE?

I realize that was not the question Ben Lenth was studying. However, it is the question that people making public policy decisions must ask. Because until they can answer that question, it seems that decisions to exclude those of us who hike and run with our dogs on Boulder Open space are based on little more than a bias against dogs–for whatever reason. I am very concerned that this study by Mr. Lenth will simply be regarded by those who hear of it, or see it cited, as proof of something far more than was actually studied or demonstrated.

Michael Katz