The project was carried out by students in the Tropical Rainforest Program of the Evergreen State College from 6-11 March 2010. There was an experimental element to the project: we tested whether baiting plots prior to sifting would increase sampling efficiency (in terms of species richness) and whether it would increase the capture rate of Pheidole major workers.
On 7 March we took 60 miniWinkler samples. We went to the same section of trail where samples were taken in 2008 (8.40831 -83.32742), and used the same methods to place the 60 samples. Six groups of 3-4 students were stationed at 50m intervals along the trail, which is an area of primary forest. Each group laid out a transect due west (the trail runs roughly north-south) and took 10 miniWinkler samples at 5m intervals. For each transect group, each of the 10 sample plots was randomly assigned to one of two treatments, baiting and control, such that there were 5 baiting samples and 5 controls. For baiting sample plots, two cookies (Pecan Sandies) were crumbled over the 1 square meter plot. Control plots were left unmanipulated. After 1 hour, all plots were chopped with machete and sifted, following the usual miniWinkler procedure. Sampling was completed by noon and samples were transported to the station. The 60 miniWinkler bags were hung in the laboratory building. They were hung haphazardly on six suspended rails and not grouped by transect. Samples were left to extract for 3 days.
There were pest ants in the building, mainly Tetramorium bicarinatum and Solenopsis geminata. The presence of these in the samples could be contaminants.
The samples were returned to the Longino Lab at Evergreen. All ants were removed from the samples and sorted (Thanks to Brendon Boudinot, Casey Broderick, Jill Cooper, Sarah Rosewall, and Ali Stefancich from the Tropical Rainforests class, and Abby Aspee, Cheryl Braun, and Sara Roberts from the Invertebrate Zoology and Entomology class for helping with sample sorting). One of the sample vials was lost during processing, resulting in a sample size of 59.
A report of the results can be found here. Unlike the 2008 samples, some difficult genera were not sorted to species. Nylanderia was treated as a single taxon. Hypoponera was treated as two: H. parva and all other Hypoponera. Solenopsis was treated as two taxa: S. geminata and all other Solenopsis. Thus "species" in the report are a combination of species and groups of species. The results are based only on workers (species for which only queens were found were ignored). [These samples were fully sorted to species in 2014 and the full species dataset used in later analyses.]
The 2010 Tropical Rainforests class: Avery Adams, Brendon Boudinot, Casey Broderick, Jill Cooper, Oliver Dibble, Somerset Fetter, Kym Foley, Annie Forman, Brian Gallagher, David Isomaki, Mary Lightle, Gerin Love, Heidi Montez, Britt O'Leary, Jasmine Reppen, Sara Rosewall, Andrew Scott-Busenbark, Jared Smith, Alexandra Stefancich, Dana Swarth, Jacqueline Taylor, Courtney Thomas, Carlos Duran Westergaard (Faculty and staff: Alison Styring, Jack Longino, Mark Wainwright).