Short-Term Foraging Responses of Formica polyctena to Contrasting Food Resources in a Temperate Forest

Red wood ants (Formica rufa group) exploit both animal prey and carbohydrate-rich resources, but responses of Formica polyctena to contrasting food resources remain poorly documented. We conducted a field experiment involving four F. polyctena mounds monitored over 14 days in a Scots pine forest in central Poland. Tuna, honey, mixed fruit, and sunflower seeds were presented simultaneously at each mound three times per day, and every food-taking event was counted during 15-min observation periods; repeated food-taking by the same worker was counted as a separate event. Across 672 observations, 8366 food-taking events were recorded. Tuna and honey accounted for 36.37% and 34.86% of all events, respectively, followed by fruit (17.46%) and sunflower seeds (11.31%). An exploratory mound-level Friedman rank analysis indicated a strong overall difference among bait types (Q = 11.77, exact permutation p = 0.000145; W = 0.981). However, with only four mounds, exact Wilcoxon pairwise comparisons followed by Holm adjustment were mathematically incapable of reaching significance and were therefore not used to support pairwise conclusions. Exploratory negative-binomial GEE analysis indicated higher food-taking event rates at 12:00 and 17:30 than at 06:30, whereas temperature and precipitation showed no independent significant associations after accounting for sampling-day differences. The findings provide exploratory evidence consistent with the hypotheses and should be interpreted as short-term, within-study patterns rather than population-level estimates.