The survival of fruit-infesting insects after bird ingestion and gut processing has been verified in very few cases, and little is known about its ecological significance. It has already been reported that the torymid wasp Megastigmus aculeatus (Swederus) survives passage through the digestive tract of frugivorous birds in the larval stage in rose seeds, but now, for the first time this has been demonstrated in hips consumed by birds in a natural environment, after collecting droppings in the field during winter and verifying wasp survival and emergence almost two years later. The rate of rose seed infestation was c.5% and the survival rate c.88%. The adult emergence rate was noticeably lower in droppings collected in early winter (54.5%) than late winter (87.5%), probably because the seeds collected in early winter were kept at room temperature (approximately 22° C) before those collected in late winter and the minimum time of exposure to low temperatures needed by the larvae to complete the diapause and continue morphogenesis had not elapsed. The results support the hypothesis that the role of frugivorous birds, particularly Turdus blackbirds and thrushes in Europe, could facilitate the dispersion of this torymid species as adult wasps have very limited flight capacity.