Lake Forest College, Biology, Vancouver, WA 98683
Savannas are composed of tall grasses, dense brush, and open forests. One goal of the McHenry County Conservation District is to restore overgrown native savanna habitats through brush removal and re-seeding. These restoration efforts attempt to restore native species of plants and animals and remove invasive and introduced species. Often, it is difficult to determine when a human designed management plan has succeeding in mimicking the original environment. In order to monitor the restoration efforts and how species respond to the changes, a model study organism is needed that fits four main categories; easy to collect, responds rapidly to the change, reproduces quickly, and can be found throughout the environment being tested. Ants play many ecological roles, such as feeding on decaying wood matter (Camponotus pennsylvanicus) or moving plant’s seeds underground. Previous studies in Australia’s tropical Kakadu region across a range of habitats, have shown that ants can be used as an indicator of microbial biomass and therefore nutrient cycling. Anderson and Sparing (1997) demonstrated that ants may also mimic how other organisms react to environmental change. This suggests that ants can be used as an indicator to document the effects of savanna restoration on local diversity. Restoration of a savanna, through brush clearing and re-seeding, may affect animal diversity both in the short and long term time scale. We are determining if the species richness or diversity of ants found at different sites correlates to the age of restoration. We also want to know what sampling methods are the most efficient for surveying northern savanna environments for ants. We employed two methods of sampling, pitfall traps and leaf litter sampling, at 21 savannah sites in McHenry County, Illinois. Between the months of June and July 2012, 30 pitfalls and five leaf litter samples were taken from each of the sites. Once back in the lab the ants were separated from other insects and then identified to species. So far, we have identified over 1,000 individuals from 38 species in the pitfalls from nine sites. Each site had an average of 17.56 (± 2.12 SE) species, with a range of 4 - 24 species. Of those 38 species, Myrmica americana and Lasius alienus have been found at all nine of the sites and account for 23.36% of all individuals. Our next step is to complete identifications for the other 12 sites sampled. We plan to use this data as a way to identify possible indicator species for the rapid identification of high quality savanna habitat, as well as which species are more likely to be found in extremely overgrown and/or extremely disturbed savanna habitats.
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