Striated Heron - Description and Ecology

Description and Ecology

Adults have a blue-grey back and wings, white underparts, a black cap and short yellow legs. Juveniles are browner above and streaked below.

These birds stand still at the water's edge and wait to ambush prey, but are easier to see than many small heron species. They mainly eat small fish, frogs and aquatic insects. They sometimes use bait, dropping a feather or leaf carefully on the water surface and picking fish that come to investigate.

They nest in a platform of sticks measuring between 20–40 cm long and 0.5–5 mm thick. The entire nest measures some 40–50 cm wide and 8–10 cm high outside, with an inner depression 20 cm wide and 4–5 cm deep. It is usually built in not too high off the ground in shrubs or trees but sometimes in sheltered locations on the ground, and often near water. The clutch is 2–5 eggs, which are pale blue and measure around 36 by 28 mm.

An adult bird was once observed in a peculiar and mysterious behavior: while on the nest, it would grab a stick in its bill and make a rapid back-and-forth motion with the head, like a sewing machine's needle. The significance of this behavior is completely unknown: While such movements occur in many other nesting birds where they seem to compact the nest, move the eggs, or dislodge parasites, neither seems to have been the case in this particular Striated Heron.

Young birds will give a display when they feel threatened, by stretching out their necks and pointing the bill skywards. In how far this would deter predators is not known.

Widespread and generally common, the Striated Heron is classified as a Species of Least Concern by the IUCN; this holds true whether the Lava Heron is included in B. striata or not.