Study says oil, gas development disrupts deer eating habits

CASPER — Oil and gas development throughout Wyoming’s sagebrush habitats may be affecting mule deer well beyond the perimeters of a well pad, a new study by University of Wyoming researchers found.

For each acre of mule deer habitat overtaken by energy-related infrastructure, nearly five additional acres are also compromised, the study concluded.

Scientists have been aware of mule deer’s skittishness around oil and gas sites for some time. The sounds, smells and sights of drilling, along with associated human activity, often deter the sensitive animals from passing through, even in areas replete with delicious foraging opportunities.

Previous research conducted by UW found a 36 percent drop in the number of mule deer on the Sublette County’s Pinedale Anticline over 15 years of energy growth. But new findings published Wednesday added another dimension to researchers’ understanding of mule deer behavior in the energy-rich fields of Wyoming.

For the study, which was conducted in the state’s Green River Basin, a group of scientists monitored 146 deer around several energy sites with an eye on how their skittish subjects foraged for sagebrush. Mule deer have a particular penchant for areas with tall, new leader shoots of sagebrush.

But in the study, oil and gas activity had a resoundingly negative impact on the animal’s foraging patterns. The most destructive disturbance for mule deer came from human activity at energy sites, leading to an over 10 percent decline in foraging, the report stated. What’s more, these repeated interruptions and corresponding habitat loss could affect mule deer population over time.

“Typically habitat loss is quantified by direct habitat loss, say where well pads go, but the reality of it is that the habitat loss expands beyond that direct loss,” lead scientist Samantha Dwinnell said. “There is an indirect habitat loss that’s prompted by (mule deer’s) avoidance behavior.”

Though Dwinnell acknowledged the central role energy played in the state’s economy, she hopes her team’s findings will provide developers and regulators with some food for thought.

“Oil and gas development is a huge part of the economy in Wyoming, and we all use those resources,” Dwinnell said. “So to say to halt all development is completely unrealistic. But what these results can provide is a more realistic understanding of what is going to happen when energy development does occur.”