DOUBLE-CRESTED CORMORANT (Phalacrocorax auritus)
DESCRIPTION: The Double-crested Cormorant is a relatively large seabird with generally black plumage, and black legs and feet. Sexes are similar except for the white crest, worn only by the breeding male. The bill upper mandible ends with a hook. The skin around the bill is bare and orange-yellow. The length of this bird is around 90 cm (35 inches). There are several subspecies.
VOICE: https://www.xeno-canto.org/species/Phalacrocorax-auritus – This bird is generally silent, but when it makes calls, they sound like pig grunts.
NAME: The English name ‘Cormorant’ comes from French patois ‘Cor marin’ due to its similar appearance to the Crow (in size and color) (Choate). The bird is named ‘Double-crested’ because the breeding male displays a bilateral crest of white feathers. The Latin genus name ‘Phalacrocorax’ also refers to a crow, and the Latin species name ‘auritus’ means ‘ear’, in reference to the bird’s crest.
HABITAT: In spite of its classification as a ‘seabird’, the double-crested cormorant can be found inland around fresh water such as rivers and lakes.
DIET: Mainly fish – these birds hunt by diving at depths that can reach more than 20 feet (6 meters). They propel themselves under water with their webbed feet, and a dive can last more than one minute.
NESTING: Double-crested cormorants nest in colonies on cliffs or on trees, often on sheltered islands. After a number of years the trees where they built their nests die from guano buildup, so the birds need to find new nesting grounds. Around six light blue eggs are laid, which are incubated by both parents. The chicks are fed by both parents.
DISTRIBUTION: The double-crested cormorant is a North-American species. Its breeding range covers the Canadian Atlantic provinces, the coastal areas along the St. Lawrence River, the Great Lakes region and the Prairie region. It is a year-round resident along the west coasts of most of North America and Cuba, and all of Florida. On migration it can be observed across the USA, and its wintering range is mainly the south-central USA.
ON PEI: The double-crested cormorant breeds on Prince Edward Island and is very common except in the winter.
There’s a fairly large group of those cormorants on the pillars of the old Hillsborough bridge in Charlottetown. They are very resilient to the weather, and will only seek shelter elsewhere during really bad weather.
CONSERVATION: This bird is considered as a ‘nuisance‘ by some groups as they believe they hunt commercial fish. However analysis of the double-crested cormorant’s stomach content appears to contradict that reputation. In some areas double-crested cormorants are culled as they are considered a threat to the eco-system, including vulnerable bird species.
NOTES: Double-crested cormorant feathers are apparently not completely waterproof even if this is supposed to be a ‘seabird’. It can frequently be seen drying its wings by opening them against the wind when back from fishing (see photo and video below).
Double-crested cormorants fly in a V-formation to save energy.
SIMILAR SPECIES: Great Cormorant
https://www.mba-aom.ca/jsp/toc.jsp (Maritimes Breeding Bird Atlas)
http://www.nhptv.org/natureworks/doublecorm.htm (New Hampshipre PBS)
Double-Crested Cormorant (.pdf document, Alaska Fish and Wildlife Service)
https://nature.mdc.mo.gov/discover-nature/field-guide/double-crested-cormorant (Missouri Department of Conservation)
This video below shows a double-crested cormorant drying its wings on a pillar of the old Hillsborough bridge. Those pillars are white from the birds’ guano.