Red-Eyed Herons: A Look at the Yellow-Crowned and Black-Crowned Night Herons
This morning at sunrise, the tide was just right for observing wading birds as the high tide receded, exposing the mudflats and oyster beds. The area was bustling with activity: Snowy Egrets, Great Egrets, Tricolored Herons, and a Wood Stork. However, what truly caught my eye were a pair of Yellow-crowned Night Herons wading in and out of the marsh grasses, searching for blue crabs. Nearby, a lone Black-crowned Night Heron foraged in the pools, hunting small fish stranded by the outgoing tide. Witnessing these two species "side-by-side" for the first time allowed me to observe differences in their foraging methods and behavior, yet they shared a striking similarity: their vivid red eyes.
The Yellow-crowned Night Heron (Nyctanassa violacea) and the Black-crowned Night Heron (Nycticorax nycticorax) are two distinct species of night herons, and they have several differences in appearance, behavior, and habitat preferences. Here are the key differences:
Appearance
Yellow-crowned Night Heron
Head: Adults have a black head with a prominent yellow to white crown and a distinct white cheek patch.
Body: The body is generally gray with some darker streaking and pale edges on the feathers.
Eyes: Typically red.
Legs: Yellow to orangish legs.
Size: Medium-sized, slightly smaller than the Black-crowned Night Heron.
Black-crowned Night Heron
Head: Adults have a black cap that extends down the back of the neck.
Body: The body is gray with a black back and wings.
Eyes: Red.
Legs: Yellow to greenish-yellow legs.
Size: Medium-sized, slightly larger than the Yellow-crowned Night Heron.
Behavior
Yellow-crowned Night Heron
Diet: Primarily feeds on crustaceans, especially crabs and crayfish.
Foraging: Often seen foraging during the day as well as at night, especially during low tide when crustaceans are accessible.
Nesting: Prefers to nest in colonies in trees or shrubs, often near water bodies.
Black-crowned Night Heron
Diet: More generalist feeder, consuming fish, amphibians, insects, small mammals, and crustaceans.
Foraging: Typically more nocturnal, foraging mainly at dusk or night.
Nesting: Often nests in large colonies, usually in trees or shrubs near water, sometimes on the ground in reed beds or on cliffs.
Habitat
Yellow-crowned Night Heron
Range: Found in the southeastern United States, the Caribbean, Central America, and parts of northern South America.
Preferred Habitat: Coastal regions, mangroves, swamps, marshes, and riverbanks.
Black-crowned Night Heron
Range: Found almost worldwide, including North and South America, Europe, Africa, and Asia.
Preferred Habitat: A variety of wetlands including marshes, rivers, lakes, reservoirs, and coastal regions.
Vocalization
Yellow-crowned Night Heron
Calls: Known for a series of harsh, barking calls, especially when disturbed or during flight.
Black-crowned Night Heron
Calls: Emits a loud, harsh "quawk" or "wok" sound, often heard at dusk and during flight.
By observing these characteristics, one can distinguish between the Yellow-crowned Night Heron and the Black-crowned Night Heron in the field.