Ring-necked ducks are small diving ducks that breed in shallow freshwater wetlands in northern North America. It’s easy to tell the difference between males and females if you know what to look for, so keep reading and you’ll soon be able to make confident ID calls, even from a distant lake shore.
Female ring-necked ducks are mainly dark brown, with lighter brown bellies, and gray markings on their faces. They have a distinctive angular head, with a reverse crest at the rear. However, despite their name, they do not have a visible ring around their neck.
Out of breeding season, male ring-necked ducks – which are usually black, white and gray – molt into a plumage that is less bold than their normally distinctive markings and they become more alike in appearance to females.
However, as pairs separate as incubation starts, any ring-necked duck you see incubating eggs or accompanying young ducklings will be a female, without a doubt.
One of the smaller diving duck species, female ring-necked ducks are similar in appearance to female scaups, redheads, and female tufted ducks. By reading our guide below, you’ll learn how to tell the difference between each of these similar-looking waterbirds.
Ring-necked Duck (female) swimming on the lake
Male and female ring-necked ducks are unalike and easy to tell apart, mainly during the breeding season. Males are mainly glossy black, with gray flanks and underparts and bright yellow eyes. In contrast, females are mainly brown, with grayish-white facial markings, white eye-rings, and brown eyes.
Males have a white triangular patch where their wings meet the breast, and their gray bills are marked with a white outline at the base and have a distinct white band just above the tip, which is black. Their eyes are bright yellow.
Males and females both share the same unusual head shape, with a flattish back and reverse crest at the back of the crown. Males are slightly larger than females, but there is some overlap between the size range of the sexes, and from a distance, any difference is not immediately obvious.
After the breeding season ends, males molt into a nonbreeding (eclipse) plumage, which is duller than their striking black and white coloring, seen in spring.
However, it is still easy to tell the difference between nonbreeding males and females, as the males’ eyes remain yellow, compared to the brown eyes seen in females. Males in eclipse plumage are darker than females, with black backs and dull black heads and gray-brown flanks
Female Ring-necked Duck
Male Ring-necked Duck
Female ring-necked ducks have angular heads, with a short peak at the rear of the crown. They have a dark brown back and light brown flanks and wings. Their heads are gray, with delicate white markings around the base of the bill, and a light brownish-gray chin and throat.
The bill of a female ring-necked duck is gray, crossed with a lighter-colored band. Females have brown eyes that are surrounded with a white eye ring, and their legs and feet are gray-blue.
Despite the species’ name, a visible ring around the neck of ring-necked ducks is not one of the main distinguishing features of either a male or a female ring-necked duck. A collar of brown feathers is faintly visible at close range on a breeding male, but absent on females.
Close up of a female Ring-necked Duck
Although there is some overlap in size range between male and female ring-necked ducks, males are usually slightly larger in both length and weight. Females are between 39 cm and 43 cm (15.4 in and 16.9 in) in length, compared to males, which are 40 to 46 cm (15.7 in to 18.1 in).
The mass of adult female ring-necked ducks falls within the range of 490 g to 894 g (17.3 oz to 31.5 oz), while males are marginally heavier, weighing between 542 g and 910 g (19.1 oz and 32.1 oz).
Male and female Ring-necked Duck pair swimming together
Ring-necked ducks are a migratory species, breeding across Canada and the northern U.S. and wintering further south and inland into the southern and central U.S. Males leave for their wintering grounds ahead of females.
Neither males or females are especially territorial, and females will abandon nests quite late into the breeding cycle if they feel threatened.
Not much data exists documenting different calls of male and female ring-necked ducks, and they are observed to be a relatively quiet and unvocal species.
During courtship, males can be heard making a weak, low-pitched whistling sound, while the calls made by females have been likened to soft purrs.
Male Ring-necked Duck in alternative plumage outside of the breeding season, where they look much more like females - note the bright yellow eyes of the male
Ahead of the nesting season, pairs undertake prospecting trips together to identify a suitable nest site. Females swim into areas of flooded vegetation, while males keep a watchful eye from a distance in open water.
Nest sites are identified up to 12 days ahead of laying, and the female gathers sedge and other waterside vegetation matter to form a rough bowl-shaped construction on which she lays her eggs.
Until the clutch is complete, the male may accompany the female to the nest site, but once incubation begins, the pair bond is lost, and the male ring-necked duck plays no further active part in raising the young or supporting the female with feeding and parental care.
The diet of male and female ring-necked ducks is mostly the same in composition, with a large proportion being plant matter foraged during underwater dives, as well as aquatic animals.
During the breeding season, food eaten by females is observed to include a greater number of larvae, leeches, snails, clams, and dragonfly nymphs than during the rest of the year.
Female left, and male right, Ring-necked Duck pair
Head shape rather than plumage is the key identifier for female ring-necked ducks when seen alongside similar species. Their flattened angular head is a contrast to the rounded head of the female tufted duck, although the females of both species have dark brown coloring and do look alike from a distance.
Female scaups are also quite similar to female ring-necked ducks, sharing the same brown plumage and body shape, but has a telltale yellow eye, and a much bolder white patch surrounding the base of the bill.
Male scaups in eclipse plumage are also another contender to confuse those observing from the shore of a lake. They are the same mixed brown, but again, males have yellow eyes, rather than the brown of a female ring-necked duck.
Female redheads are potentially the closest species in appearance to a female ring-necked duck, with the same white ring around the eye and brownish-gray plumage, but ring-necked females are slightly smaller and their head shape makes it easier to confidently give an accurate ID.
A group of male Ring-necked ducks in pursuit of a female
Female ring-necked ducks raise their young without any input or intervention from their mate. Pair bonds dissolve as incubation begins, so female ring-necked ducks routinely raise their young alone from brooding eggs before they hatch to accompanying and protecting young ducklings for the first few weeks of their lives.
Female ring-necked ducks are primarily dark brown, with lighter brown sides, and a paler, gray head with white markings around the beak.
There isn’t much documentation about the calls of ring-necked ducks, and they are not generally observed to be a very vocal species. Females can be heard to make soft purring calls to their mates during courtship, but outside these reports, little is known.
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