Canada Goose

• It pairs for life and flies in its characteristic V formation.
• There is a marked variation in size across its 7 recognised subspecies.
• One documented bird reached 42 years.
• It can cover up to 2,400 km in a single day of flight, using the V formation.
• That ability creates a practical management problem: in Spain it is impossible to know whether an individual comes from the introduced populations of central Europe or is a natural vagrant arrived from North America.
• In the areas where it settles it behaves aggressively towards moorhens and coots, which it drives out of their territories and whose young it will even prey on.

Skeleton type

Vertebrate - pneumatised bony skeleton (bird)

Habitat & environment

A wide range of open habitats near water in North America, widely introduced to Europe, Australia and New Zealand

Birth weight

85.5 grams

Size at birth

Precocial, covered in yellow down with a grey-green head, able to walk, swim and feed itself soon after hatching

Sexual maturity

2-3 years

Gestation / incubation

25-30 days

Litter / clutch size

2 to 10 eggs per clutch (most commonly 4-5)

Lifespan in captivity

A documented record of up to 42 years (with an unconfirmed anecdotal report of 80)

Sources consulted: AnAge (genomics.senescence.info); Alaska Dept. of Fish and Game; Animal Diversity Web; Internet Center for Wildlife Damage Management; Wildlife Conflicts Indiana; Cornell Lab All About Birds; Wikipedia (Vancouver Canada goose)

Best time: In winter, when the odd individual turns up mixed in with flocks of greylag geese