Study finds Wyo gas fields abuzz with invertebrates

A pair of peer-reviewed papers examining how insects are faring in reclaimed portions of the Pinedale Anticline and Jonah gas fields found major population and diversity upticks, as well as evidence that breaking up the sagebrush benefits pollinators. 

To make those determinations, former University of Wyoming PhD student Mike Curran, of the Wyoming Reclamation and Restoration Center, examined 28 reclaimed well pads in the two Green River basin gas fields from 2015 to 2017. The first study, focused on the Anticline, found a surge of bug numbers and families where native grasses were planted on reclaimed well pad ground — and even greater gains where Rocky Mountain bee plant was seeded. A subsequent study, examining infill drilling sites on the more southerly Jonah Field, suggests that native, flowering vegetation planted on rehabilitated ground provided nodes of seasonal habitat for pollinator insects that were well occupied relative to undeveloped sagebrush. 

“It definitely shows that there are some positive benefits from the reclamation that’s being done up there,” said Curran, who now owns a consulting business, Abnova Ecological Solutions. “My hope is that by getting these native vegetation communities established with more diversity than what was there, the long-term benefit is that, as the noise [from development] moves out, some of these other wildlife species will move back in.” 

The Jonah and Anticline, large Sublette County gas fields developed around the turn of the century, have been testbeds for researchers studying how industrializing sagebrush-steppe habitat influences native wildlife like sage grouse, pronghorn and mule deer. Decades of monitoring and research have found that all three of those iconic sagebrush-dwelling species have suffered. Despite mitigation efforts, mule deer abundance during drilling on the Anticline declined by 36%. Over the long run, pronghorn avoided the area, too, following the unraveling of an effort to develop a pronghorn-friendly gas field. Sage grouse, likewise, collapsed in the gas fields: males gathering on leks in densely drilled areas fell by half during an era when grouse numbers were otherwise flat in the region. 

Sage grouse and mule deer struggles in the Anticline persisted into 2022, according to recent reporting by the Pinedale Roundup and Sublette Examiner. 

With that history, Curran’s findings about gas drilling reclamation areas being a potential boon for bugs presents a silver lining for gas companies that have invested funds in mitigating wildlife impacts. 

Josh Sorenson, Jonah Energy’s lead reclamation specialist and a co-author on Curran’s papers, said the results suggest that one long-run benefit of drilling is that the reclamation that follows could be cast as a landscape-level habitat restoration project. In the Jonah Field, he said, the sagebrush is at a minimum 80 years old, and it’s dying and tends to grow as a monoculture. 

Of the Jonah Field’s roughly 30,000 acres, “we have disturbed, through our operations, roughly 10,000 acres,” Sorenson said. “We reclaimed 8,000 and what our monitoring data has shown us is that on the 8,000 acres we’ve reclaimed, we have increased herbaceous production.”

Monitoring shows that herbaceous production has increased from roughly 270 pounds of plant growth per acre to 450 pounds per acre, he said. Jonah uses a native seed mix that averages 16 species to replant areas that have been scraped. 

“So across 8,000 acres, you can say that this is a habitat regeneration project,” Sorenson said. “The reclaimed land is closer to desired rangeland conditions than, say, undisturbed ground.”

Curran’s research shows how insects can capitalize. In the Anticline, he found that insect abundance was 6 to 12 times greater on reclaimed ground seeded with Rocky Mountain bee plant flowers than in the unbroken sagebrush. Restored 5-acre pads seeded with native grasses had 3 to 4 times more insects. Pollinator abundance increased between 8 and 12 fold. 

In the Jonah Field, likewise, there were major gains for insects on reseeded ground compared to unbroken sagebrush. 

“Natural resource extraction is expected to continue into the foreseeable future with growing populations,” Curran wrote in his conclusion. “Reclamation and restoration of areas disturbed for energy extraction will become increasingly critical to restore habitat for wildlife species including insects, and therefore is important to overall insect conservation.” 

Curran’s research was supported by Jonah Energy via a gift to the University Wyoming’s Reclamation and Restoration Center, but the gas company did not dictate his research or influence findings, he said. 

Jonah Energy keeps its hands out of research like Curran’s, Sorenson said, for the good of reclamation efforts. 

“Not only for myself, but folks with the other companies, they’re interested in figuring out, OK what are our impacts?” he said. “What does the research show and how can we make improvements or adjustments based on that research?” 

One conservationist who’s lobbied and litigated against Wyoming gas fields met the results of the insect research with a degree of skepticism. Western Watersheds Project Executive Director Erik Molvar noted that the non-well pad reference areas Curran looked at averaged as much as 45% bare ground. 

“This may be indicating that the Jonah Field is badly overgrazed by livestock, which is eliminating understory plants and transitioning the site away from native forbs and perennial grasses,” Molvar said. “Elimination of the grass and forb understory could impoverish the insect assemblage, meaning that the real story might be that unsustainable levels of livestock grazing are playing a major role in suppressing insect populations.”