Unlike most owls, which hunt in silence, the Brown Fish Owl lacks the specialized soft wing feathers for muffled flight - a trade-off for its specialized diet. It possesses long, unfeathered legs and rough-textured soles designed to grip slippery, aquatic prey like fish, crabs, and frogs. Brown Fish Owl is often seen at dusk perched on branches overhanging water. In body size, it ranges from 48 to 61 cm with a wingspan from 125 to 140 cm. Its weight varies considerably, ranging from 1.1 to 2.5 kg. Females are invariably at least somewhat larger than males.