Please note: The Canadian population of least bitterns is estimated at less than 1000 pairs. The majority of least bitterns that breed in Canada are found in Ontario.
- One of the smallest herons in the world at 28-36 cm it is more likely to be heard with their low “coo-coo-coo” call than seen.
- Have a long neck and bill. The bill is yellow with dark upper edge.
- Crown and back are black or dark brownish.
- Neck and sides are orange-brown.
- Front of neck and chest striped orange and white.
- Large golden patches in wings are visible in flight.
- White lines along the sides of dark back.
- Legs pink at top, green in front, and yellow behind.
- Pale yellow eyes.
- Males are darker than females. The top of the female’s head, the back and the tail are chestnut; it has two buff lines on its back and its throat and underparts are streaked with brown.
- Juvenile birds resemble the females but the feathers on the back have buffy tips and the crown and back are a light brown.
Habits and Reproduction
- Often seen at the base of cattails at the edge of the water.
- Holds a still, reed-like pose at the water’s edge while waiting for the approach of fish and other prey.
- Builds its nest on a clump of marsh vegetation barely above water level.
- Clutch size varies from 2 to 6 (usually 4 or 5) bluish- or greenish-white eggs.
- Thought that least bitterns can have two broods in one season.
- Large (5+ha) quiet freshwater marshes with dense tall aquatic vegetation, usually cattails, interspersed with clumps of woody vegetation and open water.
- Loss of wetlands, for example 90% of wetlands in south western Ontario are gone.
- Disturbance of nest areas by activities such as boating.
- Collision with cars and electric power lines.
- Migratory hazards, such as severe weather.
- Support the protection of wetlands.
- Avoid wetland areas with your motor boat or if you must travel near wetlands, reduce speed so that no wake is produced.