Southeast Prairies and Sandstone Prairies Biological Landscape Research

The Southeast Nebraska Flagship Initiative is a partnership that includes The Nature Conservancy, Northern Prairies Land Trust, Spring Creek Prairie Audubon Center and the Nebraska Game and Parks Commission. The implementation of Flagship Initiatives—including that in the Southeast Prairies Biologically Unique Landscape (BUL)—follows from the Nebraska Legacy Plan to implement a proactive approach to conserving non-game wildlife and biological diversity in an adaptive management framework.

Despite providing many services, the tallgrass prairie and its ecological community is one of the most endangered ecosystems in North America. Remaining habitat exists as remnants in a highly-fragmented landscape. To make informed conservation decisions, we need to better understand the effects of this fragmentation. Using the ecologically important insect groups, ants and ground beetles, this study provides baseline data on the biological diversity of southeast Nebraska prairies and investigates what management, landscape, and habitat characteristics affect them. Pitfall trap sampling was conducted in 23 tallgrass remnants scattered throughout the Southeast Prairies Biologically Unique Landscape in 2010 and 2011. Multi-model inference was used for analysis of the data.

Goals

To most effectively and efficiently manage prairies, while maintaining critical plant-insect relationships indicative of system fluctuation.

Current Status

This project is complete. Twenty-eight species of ants were collected with the majority being grassland-obligates. With a positive correlation, model selection results indicate that Shannon diversity of grassland ants is best predicted by the average number of grass species per m2 while their abundance is positively associated with the amount of nearby hay meadow. Most ants belonged to the Opportunist and Cold Climate Specialist functional groups. A comparison with prior studies indicates this functional group composition to be most similar to cool-temperate forests. Though different habitats, their cooler climates likely produce this similar composition.

Nineteen species of ground beetles were collected, with two species comprising nearly 95% of the collection. These two species are incapable of flight, a physiological factor that may contribute to their high abundances by leaving them hidden from predators. As with grassland ants, the strongest predictor of Shannon diversity for ground beetles was the average number of grass species per m2.

Results suggest that ants and ground beetles are non-randomly distributed in relation to landscape, habitat, and management factors. High abundances of grassland-obligate ants are associated with high amounts of hay meadow suggesting these areas may be a priority for ant conservation. Results also suggest that sites with more grass species sustain more diverse communities of ants and ground beetles, information that can be incorporated into relevant conservation decisions.

Grassland Wildflowers
Grassland Wildflowers
Pitfall Specimen
Pitfall Specimen
Principal Investigator(s)
-Craig R Allen, NE CFWRU, Chris Helzer, The Nature Conservancy, Jarren Kuipers, Natural Legacy Program, and Gerry Steinauer, Nebraska Game & Parks Commission
Graduate Student(s)
-Kody Unstad (2012), Christopher Wood (MS UNO)
Funding
-The Nebraska Game and Parks Commission