This data set provides behavioral data for a pecking assay designed to assess the preferences of animals among different colors in a non-mating scenario. This data set provides the total number of pecks at red, orange, yellow, green, blue, white, and black dots summed across two replicate measures of pecking behavior for each tank in each testing environment. Some tanks only pecked on one occasion. For those, we simply report the number of pecks on that trial. Sire ID, Dam ID, Tank ID, Sire Population, Dam Population, and Rearing Environment are as reported in Table A1. Tanks with fewer than 5 total pecks in a given testing environment were excluded from the analysis.