American Bittern
Botaurus lentiginosus
The American Bittern is a master of camouflage, making it one of Oregon's most elusive marsh birds. Both males and females are remarkably similar in appearance, designed to blend seamlessly into their dense wetland habitats. However, there are some subtle differences:
General Appearance (Both Sexes):
Size and Shape: Medium-sized herons, standing about 23-34 inches (60-85 cm) tall, with a stocky body, relatively short legs, and a thick neck. They appear somewhat compact compared to other herons.
Plumage: Their plumage is primarily streaky brown and buff, providing superb camouflage in reeds and cattails. The upperparts are mottled brown with fine black speckles, while the underparts are heavily streaked with brown and white. This streaky pattern runs vertically, allowing them to disappear by pointing their bill skyward and swaying gently, mimicking the surrounding vegetation (a behavior known as "bittern pose").
Facial Features: They have a distinctive black streak or patch that extends from below the eye down the side of the neck. Their eyes are yellow.
Bill: Their bill is strong, straight, and dagger-like, used for spearing prey. It's typically yellowish or greenish-yellow.
Legs and Feet: Their legs and feet are greenish-yellow.
Sexual Dimorphism (Subtle Differences):
Size: Males are generally slightly larger and heavier than females. This difference can be difficult to discern in the field unless you see a pair together or have specific measurements. For example, male wing length and bill length tend to be a bit longer than females.
Neck Streak (Black Patch): The black streak or patch on the side of the neck is typically larger and more prominent in males than in females. This is one of the more reliable (though still subtle) visual cues to differentiate the sexes.
Vocalization: This is arguably the most significant difference. During the breeding season (spring and early summer in Oregon, typically May to July), the male produces a loud, low-pitched, booming call often described as "oong-ka-choonk" or "pump-er-lunk," giving the bird nicknames like "thunder-pumper" or "stake-driver." This call can carry long distances and is primarily used by the male to advertise his territory and attract females. Female vocalizations are less well-known and less prominent.
Juvenile American Bitterns:
Young American Bitterns resemble adults but typically lack the black neck streak or have only a very faint one. Their plumage might also be a bit duller.
Habitat and Behavior in Oregon:
American Bitterns are found in Oregon's dense freshwater marshes and extensive wet meadows, particularly those with tall emergent vegetation like cattails, bulrushes, and reeds. They are highly secretive and solitary birds, rarely seen out in the open. They prefer shallow water (a few inches deep) where they can stalk their prey.
Their diet consists mainly of fish, frogs, tadpoles, aquatic insects, crustaceans (like crayfish), and sometimes small mammals or snakes. They hunt by standing motionless at the water's edge or walking very slowly, then striking with a sudden thrust of their bill.
General Appearance (Both Sexes):
Size and Shape: Medium-sized herons, standing about 23-34 inches (60-85 cm) tall, with a stocky body, relatively short legs, and a thick neck. They appear somewhat compact compared to other herons.
Plumage: Their plumage is primarily streaky brown and buff, providing superb camouflage in reeds and cattails. The upperparts are mottled brown with fine black speckles, while the underparts are heavily streaked with brown and white. This streaky pattern runs vertically, allowing them to disappear by pointing their bill skyward and swaying gently, mimicking the surrounding vegetation (a behavior known as "bittern pose").
Facial Features: They have a distinctive black streak or patch that extends from below the eye down the side of the neck. Their eyes are yellow.
Bill: Their bill is strong, straight, and dagger-like, used for spearing prey. It's typically yellowish or greenish-yellow.
Legs and Feet: Their legs and feet are greenish-yellow.
Sexual Dimorphism (Subtle Differences):
Size: Males are generally slightly larger and heavier than females. This difference can be difficult to discern in the field unless you see a pair together or have specific measurements. For example, male wing length and bill length tend to be a bit longer than females.
Neck Streak (Black Patch): The black streak or patch on the side of the neck is typically larger and more prominent in males than in females. This is one of the more reliable (though still subtle) visual cues to differentiate the sexes.
Vocalization: This is arguably the most significant difference. During the breeding season (spring and early summer in Oregon, typically May to July), the male produces a loud, low-pitched, booming call often described as "oong-ka-choonk" or "pump-er-lunk," giving the bird nicknames like "thunder-pumper" or "stake-driver." This call can carry long distances and is primarily used by the male to advertise his territory and attract females. Female vocalizations are less well-known and less prominent.
Juvenile American Bitterns:
Young American Bitterns resemble adults but typically lack the black neck streak or have only a very faint one. Their plumage might also be a bit duller.
Habitat and Behavior in Oregon:
American Bitterns are found in Oregon's dense freshwater marshes and extensive wet meadows, particularly those with tall emergent vegetation like cattails, bulrushes, and reeds. They are highly secretive and solitary birds, rarely seen out in the open. They prefer shallow water (a few inches deep) where they can stalk their prey.
Their diet consists mainly of fish, frogs, tadpoles, aquatic insects, crustaceans (like crayfish), and sometimes small mammals or snakes. They hunt by standing motionless at the water's edge or walking very slowly, then striking with a sudden thrust of their bill.