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Rufous isn’t just a name for dogs

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Whistler Naturalists

Another sign of spring was recently sighted in the Sea to Sky corridor. This animal has flown thousands of kilometres from either southern California or central Mexico to spend its summer in our area. On March 27, Bobbi Sandkul of Pinecrest Estates south of Whistler spotted a Rufous hummingbird ( Selasphorus rufus ) at her feeder.

Our local area is a summer home to three species of hummingbird; the Rufous, the most common, is sighted here throughout the spring and summer and occasionally in the early fall. Rarely sighted in the Sea to Sky are the Calliope hummingbird ( Stellula calliope ), which is North America's smallest bird, and the Anna's hummingbird ( Calypte anna ).

The male Rufous hummingbird weighs about 3.2 g with the female being slightly larger and heavier at 3.4 g. This dimorphism is common in most hummingbird species. They are approximately 9 cm in length. This size-to-weight ratio means the Rufous has the most efficient energy usage amongst North American hummingbirds.

The male Rufous hummingbird has non-iridescent rusty brown or "rufous" coloured plumage on the top of its head (crown), tail, and sides. His back may also be rufous and/or green and his breast is white. He has a bright, iridescent, reddish-orange throat patch, which is known as a gorget. The female Rufous has green plumage on both her crown and back. She is rufous coloured only on her sides and at the base of her tail. Like the male she has a white breast but also has white at the tips of her outer tail feathers. Both the male and female juveniles have the colouring of the adult female, which can make identification difficult in the late summer/early fall after the young have hatched. Later they will molt and the male juveniles will lose this colouring.

The adult Calliope hummingbird, whose scientific name translates into "beautiful little star" is only 8 cm long. At birth they are about the size of a human fingernail. Adult males weigh 2.5 g and females 2.85 g, which is about as much as a quarter. Like the female Rufous hummingbird, both the male and female Calliope have an iridescent green back and crown. The male has a yellow breast and flank. He has a white gorget, and unlike all other North American hummingbird species that have solid coloured gorgets, the Calliope’s is streaked with purple feathers that can be erected to display a "whiskered" effect. Unlike the male, the female Calliope has a buff coloured underside and flanks. Her white gorget is freckled with dark spots. Like the Rufous, both female and male Calliope hummingbirds have dark tails; the female having white tips on the outer feathers.

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