The smallest diving ducks in North America, bufflehead (Bucephala albeola) pairs can be spotted on ponds and small lakes early in the breeding season. Males have a striking black and white plumage, with a large white facial patch. Females are smaller, and lack the distinctive markings of males, instead being grayish-brown all over, with a far smaller white cheek patch.
If you’re interested in learning about the appearance and behavior of bufflehead females, then our guide will tell you all you need to know!
Female buffleheads are compact diving ducks that nest in forests in Canada and the extreme northern U.S. Different in appearance from the striking black and white plumage of males, female buffleheads are brown and gray, with a white facial patch.
Research indicates that bufflehead pairs arrive together on their breeding grounds by April to May. Females scope out potential nest sites as early as the previous year, and are responsible for final site selection alone.
Males leave breeding grounds for their summer molt from June to July, leaving the female to incubate and raise young by herself.
To learn more about the female bufflehead’s nesting habits and other typical behaviors, then please keep reading.
Close up of a female Bufflehead swimming on the water
Male and female buffleheads are unalike in appearance, and it’s easy to tell the difference between the sexes. Males are glossy-black, with an unmistakable iridescent head, whereas females are mainly dark brown. Both sexes have a white cheek patch, but females have a much smaller patch.
Males have glossy black upper parts, white breasts and bellies, and a large white patch extending from their cheek to the back of their head. The rest of their head is black with an iridescent purple-green sheen. Males have blueish-gray bills, and pink legs and feet.
Female buffleheads are, in contrast, less conspicuous, and are mainly dark brown, with lighter gray under parts, and a smaller white cheek patch on their dull black-brown head. Their bills are a darker gray, and legs are dark pinkish-gray. In eclipse plumage males do become more similar in appearance to females, although they retain their larger white facial patch.
Female buffleheads are compact brownish-gray waterbirds, between 32 and 35 cm (12.6 in to 13.8 in) in length. They have dark brownish-black heads, with a distinctive white oval cheek patch, extending from underneath the eye towards the back of the head.
Their backs and wings are dark brownish-gray, with wings marked by a white patch, while their underparts are a paler shade of gray. Female buffleheads have short dark gray bills, dark brown irises, and dark grayish-pink legs and feet.
Buffleheads are the smallest of North America’s diving duck species.
Close up of a female Bufflehead swimming
Female buffleheads are smaller than males and weigh slightly less. Body length for females is 32 cm to 35 cm (12.6 in to 13.8 in), while males are, on average, between 35 cm and 40 cm (13.8 in to 15.7 in).
The average mass for adult bufflehead females is 337 g (11.9 oz), compared to 465 g (16.4 oz) for males.
During the course of the year, buffleheads’ body weight changes – females are at their heaviest between March and May and November, but lose a significant amount of body weight by the end of the breeding season, when their weight drops to between 270 g and 292 g (9.5 oz to 10.3 oz).
Male and female Bufflehead pair in flight
Territorial behavior is commonly displayed by bufflehead during the breeding season, with females being particularly aggressive when defending newly hatched young on the water. Males, by this point, have left for their summer molting grounds, so defense of young and nest sites is down to the female alone.
Early in the breeding season, males also exhibit territorial behavior, chasing off intruding males or pairs with an elaborate ‘threat display’.
During courtship, males display to a potential female mate by raising its head feathers, effectively expanding the white patch on its head to around twice its normal size. This is accompanied by wing flapping, head bobbing and overhead flight displays, while the female takes a more passive, observational role.
Male buffleheads are never seen on land, spending their entire lives on water or flying between breeding, molting and wintering grounds.
Females come to shore to nest, and can be seen walking when they lead their young to water from the nest cavity for the first time. They also occasionally continue to roost in a sheltered spot on a lake’s shore when their young are still immature and dependent on them for protection.
Female (left) and male (right) breeding pair of Buffleheads
Neither male nor female buffleheads are particularly vocal. Females are observed to call to their young using a low-pitched repetitive buzzing ‘cuc-cuc-cuc’ sound. They are also heard to make a distinctive rapid ‘cuk-cuk-cuk’ call when checking out possible nest sites in the summer.
Female buffleheads’ vocal repertoire also includes a loud buzzing ‘cuc-cuc-cuc’ call as a warning call or when the nest site is disturbed.
Female Buffleheads are known as hens, and males, drakes
Buffleheads are active foragers, spending a large amount of time each day diving for prey beneath the surface of lakes and ponds. Molluscs, crustaceans and insects are the most common foods. According to one set of data, female buffleheads were recorded to have a diet containing a larger proportion of insects than their male counterparts.
Buffleheads are cavity nesters, using holes in trees originally drilled out by small woodpeckers or Northern flickers. On occasion, buffleheads will use nest boxes if a suitable natural hollow cannot be found. Sites are inspected and chosen by the female, with recce missions beginning as early as the previous summer. Eggs are most commonly laid in May, with males departing for their molting grounds shortly afterwards.
Once the eggs have been laid, the female incubates alone, leaving the nest to feed twice a day, for around 80 minutes at a time. Feeding trips during incubation are most common late afternoon, and female buffleheads will remain in their nest cavities overnight while incubating.
Bufflehead eggs hatch between 28 and 33 days after the clutch has been laid, and young are ready to leave the cavity within 24 to 36 hours. On the morning of fledging, the female returns to the nest and enters the cavity. The young then leave one by one in quick succession, followed by the female who joins them on the ground below and leads them to the water.
Young occasionally continue to be brooded by the female once they have left the cavity, either on the shore or a half-submerged log. Once they reach between 5 and 6 weeks, juvenile buffleheads are typically abandoned by the female and are able to live and forage independently.
Male buffleheads depart for their summer lakes in June each year, where they undergo a full molt, changing from breeding to eclipse (nonbreeding) plumage. This means they are absent during much of the incubation period and play no active role in supporting the female with feeding or raising the young.
A small group of two male and two female Bufflehead ducks
Female buffleheads can and do raise young alone. Males typically leave for their summer molting grounds in June each year, and play no active role in nesting or raising young.
From searching for prospective nest sites almost a year in advance of laying eggs, to final site selection, incubation and eventual fledging and accompanying young in their early forays onto water, female buffleheads accomplish all of these stages without a mate.
Female buffleheads are largely grayish brown. Their backs are a darker shade of brown, which pales into a lighter gray on their breast and underparts. Their brownish-black heads feature a distinct white oval cheek patch, and their brown wings are marked with a sizable white band.
Close up of young a Bufflehead duckling
Female buffleheads are known to communicate with their young using a low buzzing ‘cuc-cuc-cuc’ call. A similar, but louder call is used to signal distress or alarm when separated from ducklings.
When scoping out potential nest sites later in the summer ahead of the following breeding season, females can be heard making a rapid ‘cuk-cuk-cuk’ call.
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