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Word of the Week: Uropygium

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Welcome to Word of the Week! Stay tuned for a new word each Friday to amp up your nature vocabulary!

Uropygium [ yoor-uh-PIJ-ee-uhm ] (noun): The posterior part of a bird’s body, from which the tail feathers grow.

Spring breathes new life into High Park as many of the residents are having babies! We’re so excited to see mallard ducklings swimming in the waters once again.

Unlike adult mallard ducks, the young ducklings do not have naturally waterproof down feathers. They will need to get the waterproofing for their down feathers from their mother. The mallard duck mama has a special oil gland that is located at her uropygium. This gland is known as the uropygial gland or the preen gland. To waterproof the feathers of her young, and also her own feathers, she will pick up the oil produced by the uropygial gland with her head and beak. She will then smear it all over her body and the bodies of her young.

Because these birds spend almost their whole lives in and around the water, this protective barrier is extremely important. Without the presence of this waterproofing, duck feathers would become super water-logged which can negatively affect body temperature regulation and could even lead to drowning.

On your next spring visit to the waters of High Park, keep an eye out for Mallard Ducks and their young!

To learn more about birds with the High Park Nature Centre, check out our “Birds of the City” Online Naturalist Course for adults