The trumpeter swan (Cygnus buccinator) is the largest native waterfowl species in North America. While males and females look quite similar, there are some subtle differences in their appearance. In this article, we will take a closer look at the key physical characteristics of female trumpeter swans.
Overall Size and Shape
The trumpeter swan is a very large bird, with adults measuring 4-6 feet (1.2-1.8 m) long and weighing 20-30 pounds (9-14 kg). Females are often slightly smaller than males but overall quite similar in their dimensions.
The body shape of female trumpeter swans can be described as long, graceful, and mostly white in coloration. Their bodies are elongate, with long necks and a wingspan of up to 6 feet (1.8 m) across. The torsos of females are rounded and wider than their necks. Their tails are short and squared off.
Overall, the trumpeter has a robust body on a long, slender neck and legs. This gives them a distinctive profile on the water. The large size and elongated shape is well-adapted for their aquatic lifestyle.
Plumage
The plumage of female trumpeter swans consists of mostly crisp white feathers covering their entire body. This includes the head, neck, back, wings, tail, and undersides.
The white plumage is accented by black coloration on the following features:
Bill
The bill of female trumpeters is broad, flat, and completely black. The black coloration covers both the upper and lower mandible. The bill has a gentle sloping profile from base to tip. In adult females, the bill may feature a reddish or pinkish hue at the borders.
Legs and Feet
The legs are thick and black. The feet are webbed with black skin connecting the front three toes. The webbing helps propel the swan when swimming.
Eyes
Trumpeter swans have rounded, dark brown or blackish eyes. The eyes are set on either side of the head.
Differences From Males
While the female trumpeter swan shares many physical traits with the male, there are some subtle differences:
Size Dimorphism
Females are often slightly shorter and weigh a bit less than males, though size can overlap significantly between the sexes. On average, females may stand 4-5 feet tall while males are 4.5-6 feet tall.
Plumage Hues
The white plumage of female trumpeters tends to have a more creamy or grayish hue compared to the pure white of males. Males often appear brighter white overall.
Bill Coloration
Adult females may show more pinkish or orange tones along the edges of the black bill, while the male’s bill is solid black.
No Knob
One of the most distinguishing features is that females lack the large black facial knob on the forehead that males possess. This fleshy protrusion grows larger during breeding season.
Attribute | Female | Male |
---|---|---|
Average height | 4-5 ft | 4.5-6 ft |
Bill color | Black with some pinkish hues | Solid black |
Facial knob | Absent | Present |
Plumage color | Creamy white | Pure white |
Juvenile Appearance
Young trumpeter swans look quite different from adults. They exhibit grey plumage starting at about 2 months old. The grey hue is a mix of slate gray and white feathers. Their bill is pinkish gray instead of black. The legs are a dull grayish color as well.
Around their first winter, juveniles may start getting some white feathers. But full adult plumage doesn’t appear until they are at least 2 years old. The bill turns black at 12-24 months old. Juvenile males do not develop the facial knob until they reach maturity.
Behavioral Differences
Beyond physical traits, female trumpeter swans display some subtle behavioral differences compared to males:
Foraging
During feeding, females often seem a bit more hesitant and wary than males. They may linger back as males initiate foraging in a new area or approach closely to humans.
Parenting
Females are solely responsible for incubating the eggs. They sit dutifully on the nest while males patrol and defend the territory. Once cygnets hatch, females tend to be more actively involved in rearing the young.
Vocalizations
The calls of female trumpeters are a bit higher-pitched and more nasal sounding than the deeper, brassy calls of males.
Interactions
Female swans are typically a little less aggressive than males. Males often boldly approach intruders first while females hang back slightly. However, females will still display aggressive behaviors like hissing and chasing when necessary.
Range and Habitat
Female trumpeter swans occupy the same geographic breeding range and habitats as males throughout northwestern North America:
Breeding Range
The trumpeter swan’s breeding habitat centers around Alaska but also includes parts of northern Canada and the northwestern United States. Female trumpeters breed in Alaska’s interior, the Aleutian Islands, and along coastal southern Alaska. They also breed in western Canada and states including Montana, Wyoming, Idaho, Oregon, and Washington.
Wintering Range
During winter, female trumpeters migrate down the Pacific Coast or to the midwestern United States. They winter in ice-free lakes, rivers, and wetlands in these regions before migrating north again for breeding. Many winter along the coasts of Washington, British Columbia, and southeast Alaska. Others occupy the Great Lakes region and interior North America.
Habitats
Female trumpeters rely on shallow ponds, marshes, and lakes with ample aquatic vegetation. They need water bodies that provide habitat for breeding as well as wintering grounds with available food resources. Nesting usually occurs on islands or shorelines with emergent wetland vegetation that provides cover and nesting material. While non-breeding, they frequent estuaries, flooded fields, marshes, and lakes.
Diet
The diet of female trumpeter swans is identical to males. They forage on a variety of aquatic vegetation and organisms:
– Aquatic plants – Feeds heavily on leaves, stems, tubers and rhizomes of pondweeds, sedges, rushes and algae. Will dive to reach food.
– Invertebrates – Consumes insects, mollusks, crustaceans and other invertebrates. These provide protein.
– Fish – Opportunistically eats small fish.
– Grains/crops – May graze in agricultural fields, especially on waste grains like corn or barley.
Females utilize the same varied foraging techniques as males. This includes dabbling at the surface, plunging their head underwater, or tipping up to reach bottom vegetation. They exhibit strong seasonal variation in diet depending on available local food sources.
Mating and Reproduction
Here are some key facts about the mating habits and reproductive biology of female trumpeter swans:
Sexual Maturity
– Females reach sexual maturity between 3-5 years old. This is when they are able to successfully breed.
Mating Season
– Breeding occurs from April through early May. This coincides with spring migration to nesting territories.
Courtship
– Female trumpeter swans participate equally in courtship rituals. This includes mutual head bobbing, ruffling feathers, and duet calling.
Nest Building
– The female builds the large nest structure from available vegetation. The nest is usually 3-6 feet wide and 1-2 feet tall on a mound.
Egg Laying
– Females lay an average of 3-6 creamy white eggs. The eggs are laid every other day.
Incubation
– The female incubates the eggs for 32-37 days until they hatch. The male stands guard nearby.
Rearing Young
– Female trumpeter swans take the lead caring for cygnets after hatching. The young stay with their parents for nearly a year before independence.
Population Status
The population of trumpeter swans crashed during the 19th and early 20th centuries due to overhunting and habitat loss. Thanks to conservation efforts, their numbers have rebounded:
- During the 1935 census, only 69 trumpeter swans were counted across their entire range.
- In 2005, an estimated 46,225 trumpeter swans existed, though many populations remained vulnerable.
- As of 2015, the global population was estimated at 63,000 individuals, with 27,000 in Alaska.
- While still below historical levels, their numbers continue to grow across much of their breeding and wintering habitat.
- In regions like Puget Sound, trumpeter swans have fully recovered and expanded beyond original boundaries.
Trumpeter swans face ongoing threats including loss of wetland habitat, poisoning from lead ammunition, and disturbance of breeding grounds. Ongoing conservation work to protect vital habitat and reduce lead exposure remains crucial for maintaining healthy, sustainable populations of trumpeter swans across North America.
Conclusion
In summary, female trumpeter swans are distinguished by their large white form, black bill often with some orange or pink hues, lack of a facial knob, and slightly more diminutive size compared to males. Behaviorally, females are a bit less aggressive and more actively involved in parental care duties. They prefer similar aquatic habitats and diets as male swans. After near extinction, trumpeter swan populations are recovering but require continued habitat protection and management efforts to ensure the survival of these elegant white waterfowl, including breeding females that are vital to future generations.