ARE EGG-BEARING MALE WATER BUGS, BELOSTOMA-FLUMINEUM SAY (HEMIPTERA, BELOSTOMATIDAE), IMPAIRED SWIMMERS

The swimming abilities of female, unencumbered male, and egg-bearing m ale water bugs, Belostoma flumineum Say (Hemiptera: Belostomatidae), w ere examined. While females and unencumbered males did not differ, bot h groups swam significantly faster than males encumbered with eggs. Th is differential performance represents a potentially large cost for ma le care in this species: slow-swimming males may suffer increased pred ation and decreased foraging success. Because encumbered males of anot her genus (Abedus) exhibit similar behavior, impaired swimming may rep resent a generalized physical constraint associated with male care in the Belostomatinae.