Data from: Resetarits, Jr., William J., Matthew R. Pintar, Jason R. Bohenek, and Tyler M. Breech. 2019. Patch size and predation risk generate behavioral species sorting in colonizing aquatic insects. American Naturalist. **Resetarits et al. 2019 American Naturalist data.csv** This is a CSV file. Block: represents the six spatial groups of pools within the experiment Pool: number assigned to each pool within a block PoolID: unique identifier for each pool in the experiment; in the form of "Block.Pool" Size: size variable of each pool; Small = 593 L, 1.13 m2; Medium = 1334 L, 2.54 m2; Large = 3002 L, 5.73 m2 Fish: whether fish were (Predator) or were not (Control) present in each pool Treatment: treatment variable combining Size and Fish above; SF = small, fish; S = small, control; MF = medium, fish; M = medium, control; LF = large, fish; L= large, control Acilius fraternus through Uvarus lacustris: these are the 51 species of beetles that colonized the experiment Buenoa through Sigara: these are the 7 taxa of hemipterans that colonized the experiment All data for the above columns are sums of those taxa in each pool across the entire duration of the experiment. Insect abundance: total abundance of all beetles in each pool across the duration of the experiment Insect richness: number of insect species recorded from each pool across the duration of the experiment Insect species density: number of insect species recorded from each pool across the duration of the experiment corrected for area Rarefied SR: number of insect species recorded from each pool across the duration of the experiment rarefied by pool Dytiscidae abundance, Hydrophilidae abundance, and Hemiptera abundance: number of insects from each of those taxa recorded in each pool across the duration of the experiment Contact information: William J. Resetarits Jr. email: wresetar@olemiss.edu Affiliation at the time of publication: University of Mississippi Department of Biology P.O. Box 1848 University, Mississippi, USA 38677 **History** version 1.0 - 28 March 2019