Members of this family are agile swimmers; you may also find them resting on aquatic plants.
Some feed on plants, while others are predaceous. Arnett notes, "A few have been known to eat small particles of solid food, the only bugs known to consume other than liquid substances" (Arnett, 2000).
The Waterboatmen are the largest family of aquatic bugs, with some 125 species in America north of Mexico. Many of the species are very difficult to identify, and quite a few can be identified only after dissection and examination of the male genitalia (and females in some cases can be identified only in association with males).
Note that this is both the genus page for Sigara and the family page for Water Boatmen
American Insects site