Within ecosystems, heterotrophs are limited by food availability and quality. Likewise, predator fitness is influenced by prey health and nutrition: Unhealthy prey can sicken their predators either through disease or nutritional inadequacy, while healthy prey can hasten predator development and enhance fecundity. Traditionally, studies on the effects of prey nutrition on predator fitness have been biased toward the larger stages, where prey-size limitations are less. However, insect fitness is affected by nutrition during all life stages. This study assessed the effect of flies fed either a standard diet (one that allowed for completion of the prey life cycle) or an enriched diet (higher in proteins, fats, and fiber) on early instar performance measures in two mantis species from different families. In both species, early development time was shorter by up to 2 days in the groups feeding on diet-enriched prey, and survival to the third instar was marginally higher. In Creobroter apicalis (Saussure, 1869) (Mantodea: Hymenopodidae), survival to the second instar was significantly higher in nymphs fed Drosophila hydei (Sturtevant, 1921) (Diptera: Drosophilidae) that had received an enriched diet, and the first and second instar durations were significantly shorter. Meanwhile, in Tenodera sinensis (Saussure, 1871) (Mantodea: Mantidae), neither survival to the second instar nor second instar duration were significantly affected by prey diet. These results show that prey feeding on a more nutritious diet (one higher in proteins and fats) can improve predator growth and survival rates but that different species have different responses to these factors.
