TRAFx Off-Highway Vehicle Counter

What is the distribution and intensity of OHV use on the landscape, and what are the impacts? The fact is, no one really knows. Yet many government agencies, scientists, conservationists and recreationists need to answer this critical question in order to manage lands well.

Part of the reason so little is known about the intensity and distribution of OHV use is that an effective tool for monitoring OHV use has not been available. Last month, a lawyer for a Montana-based organization told me that the U.S. Forest Service has a legal obligation to monitor OHV use levels, but has not done so, claiming that the tool to do so did not exist. Such a tool is now available. The TRAFx Off-Highway Vehicle Counter combines tiny precision magnetic sensors, advanced digital signal processing, and sophisticated embedded software systems to create a technology for counting OHVs of various shapes and sizes.

Back in the mid-1990s I was involved in one of the first Canadian applications of the U.S. Forest Service’s cumulative effects model for grizzly bears. To determine how useful an area is to grizzly bears, both habitat quality and levels of human use must be quantified accurately. While it was relatively straightforward to quantify habitat quality through hundreds of field plots, it was very difficult to accurately quantify levels of human use on the landscape. This substantially limited the efficacy of the model.

In the area where I was, the dominant type of human use was motorized recreational use — mainly ATVs and dirt bikes. In the study area, forestry, oil and gas activities, and coal mining had collectively created a dense network of trails and roads used by OHVs in grizzly bear habitat. These spatially abundant linear features used by motorized recreational vehicles in fact “drive” the cumulative effects model and strongly influence how useful an area is to grizzly bears.

Because the proper tool to inventory OHV use was unavailable, I became determined to create such a tool. Five years after my initial crude prototype, I am pleased to say that a sophisticated, flexible, micro-computer based OHV detection, counting and monitoring tool has arrived. The TRAFx Off-Highway Vehicle Counter has the following key features:

• quick to deploy, and easy to hide (bury in the road or place it beside the road under a rock)
• long battery life (three AA batteries last four months; three C batteries last a year)
• small size (including AA batteries and waterproof field case, it is the size of a bar of soap)
• user configurable settings (auto-start time, adjustable sensitivity, time stamps, variable-length period counts)
• low maintenance (no moving parts, or wire loops or rubber tubes to damage)
• large memory capacity (can store over 10 million counts if necessary)
• designed for outdoor environments (the precision sensor is rated to -40 C)
• data easily transfers into spreadsheet programs (works great with Microsoft Excel)
• connects to a handheld, laptop or desktop PC (the small Compaq iPAQ is excellent for the field)

To date, the TRAFx Off-Highway Vehicle Counter has mainly been used in the Canadian Rockies in Alberta and British Columbia in environmental cumulative effects assessments. The Biological Division of the U.S. Geological Survey recently ordered some of the counters for a research project near YellowstoneNational Park.

While the U.S. Forest Service cumulative effects model for grizzly bears (which I used in the 1990s) has gradually been replaced with resource selection function (RSF) models, the need to gather accurate data on intensity and spatial and temporal distribution of ORV use remains critical. In RSF models, it must be determined what “resources” wildlife are selecting or avoiding. Are they avoiding motorized roads and trails used by OHVs? What is the level of OHV use that results in avoidance? These questions remain unanswered in regards to grizzly bears and other wildlife species. Because OHVs can move quickly over the landscape, can readily access remote and sensitive wildlife habitat, and are much louder than normal vehicles, they have considerable impacts on wildlife.

If you are interested in learning more about the TRAFx Off-Highway Vehicle Counter, please go to http://www.trafx.net.

— Jake Herrero is an environmental scientist who lives in Canmore, Alberta. In his free time, he shuns technology and hikes and skis in the mountains around his home.