Wyoming’s economy is largely supported by energy and mineral extraction. Due to the vast and growing nature of natural resource extraction, Wyoming rangelands are increasingly becoming degraded and fragmented ecosystems. The degraded land is reclaimed with the intent to restore the health, integrity, and sustainability of the ecosystem. However, the majority of current restoration practices aim to restore native plant and wildlife communities but do not necessarily address community structure of other keystone species, such as invertebrates. It is generally assumed that invertebrate populations are fully restored when the plant communities are restored. However, little research has been conducted in the western United States to question that assumption. We addressed the following questions: 1. Are invertebrates returning to the landscape after drastic disturbance and reclamation? 2. To what extent do invertebrates return to disturbed areas over time? 3. To what extent do indicator insect taxa return to disturbed areas over time?
Insects were sampled using a chronosequence on oil and gas well pads in the Pinedale Anticline, Wyoming. Sites ranged in age from 1-10 years post final reclamation and were split into three age classes, plus reference sites. Ants and beetles were sampled by pitfall traps that were collected every 24 hours for 3 days during June, July and August 2016 and 2017. Vegetation surveys were also collected in order to correlate insect and plant communities.
Results/Conclusions
Preliminary data have shown that ant densities are not reaching density levels of ants on reference sites until 8-10 years post reclamation. There is a significant difference in ant densities between the four age classes sampled. In contrast, beetle densities are high on younger, newly reclaimed sites. Many ant species are sensitive to disturbance and have particular habitat needs and current reclamation practices may not be suitable for ant species to recolonize quickly. Many invertebrates, including ants and beetles, are essential for survival of other important wildlife, such as the Greater Sage Grouse. If ground dwelling invertebrate populations are not returning to the landscape, there are serious repercussions for the ecological integrity of the reclaimed site.