Parental care and foraging ability in male water bugs (Belostoma flumineum)

Abstract

The predatory water bug Belostoma flumineum is one well-known insect example of male parental care. Male water bugs, while brooding eggs, may suffer several potential costs. These include the following: energetic costs, increased vulnerability to predation, and decreased foraging ability. We conducted investigations to determine whether encumbered males exhibited decreased foraging ability on two different prey types: fast moving fish (Gambusia affinis) and slower moving snails (Physella virgata virgata). Encumbered males encountered and captured snails at the same rate as did unencumbered males and females; however, encumbered males were less likely to encounter and capture the more mobile Gambusia than were unencumbered males and females. These results demonstrate that the magnitude of parental care costs in Belostoma depends in part on the relative abundance of sessile and mobile prey.