Asian needle ant (Brachyponera chinensis) and woodland ant responses to repeated applications of fuel reduction methods

Authors: CAMPBELL, JOSHUA - Auburn University; GRODSKY, STEVEN - University Of California, Davis; Halbritter, Dale; VIGUEIRA, PATRICK - High Point University; VIGUEIRA, CYNTHIA - High Point University; KELLER, OLIVER - University Of Florida; GREENBERG, CATHRYN - Us Forest Service (FS)

Submitted to: Ecosphere
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/27/2018
Publication Date: 1/15/2019
Citation: Campbell, J., Grodsky, S., Halbritter, D.A., Vigueira, P., Vigueira, C., Keller, O., Greenberg, C. 2019. Asian needle ant (Brachyponera chinensis) and woodland ant responses to repeated applications of fuel reduction methods. Ecosphere. 10(1):1-12. https://doi.org/10.1002/ecs2.2547.
DOI: https://doi.org/10.1002/ecs2.2547

Interpretive Summary: Ants are important members of forest ecosystems and can be affected by the removal of overgrown vegetation during forest management. We examined the effects of repeated instances of vegetation reduction on abundance and diversity of ants within forests in the Southern Appalachian Mountains in North Carolina, USA. We established three replicate areas and split each area into four vegetation reduction treatments, which included prescribed burning (B), mechanical thinning (M), a combination of prescribed burning and mechanical thinning (MB), and a control (C, i.e., no vegetation reduction). We treated multiple times (two mechanical thinnings and four prescribed burns) over the course of a 15-year period. Over a 3-year period (2014-2016), we captured 54,219 ants comprised of 25 genera using traps. The non-native Brachyponera chinensis Emery was more abundant in the MB plots compared to all other treatments. Vegetation reduction treatment did not affect ant genera/species richness (i.e., number of different genera/species), but there were year-to-year variations in richness. Most ant genera/species did not show year-to-year differences in abundance, suggesting that some fuel reduction practices may have impacts over longer periods or, conversely, may not impact ant abundance at all. Overall, fuel reduction treatments can alter forest ant communities thus contributing to changing forest dynamics.

Technical Abstract: Ants (Hymenoptera) are important components of forest ecosystems and can be affected by fuel reduction forest management practices. We assessed the impact of repeated applications of fuel reduction treatments on abundance and diversity of ants within upland mixed hardwood forests in the Southern Appalachian Mountains in North Carolina, USA. We established three replicate blocks (~56 ha each) and split each block into four fuel reduction treatments, which included prescribed burning (B), mechanical felling (M), a combination of prescribed burning and mechanical felling (MB), and a control (C, i.e., no fuel reduction techniques applied). We implemented treatments multiple times (two mechanical thinnings and four prescribed burns) over the course of a 15-year period. Over a 3-year period (2014-2016), we captured 54,219 ants comprised of 25 genera using pitfall and colored pan traps. Prenolepis imparis Say was the most common ant species collected and was significantly lower in abundance in MB plots compared to all other treatments. However, Monomorium spp. and the non-native Brachyponera chinensis Emery were more abundant in the MB plots compared to all other treatments. Ant genera/species richness did not differ among the treatments but did differ among years. Most ant genera/species did not exhibit any yearly abundance differences, suggesting that some fuel reduction practices may affect some ant genera over long periods or, conversely, may not impact ant abundance at all. Overall, fuel reduction treatments can alter forest ant communities thus contributing to changing forest dynamics.