Essayer OR - Gratuit
Duck, Down
African Birdlife
|May/June 2018
White-backed Duck diving behaviour
The White-backed Duck is an ab-errant whistling duck that shares several morphological features with the stiff-tailed ducks (Oxyurini) because of their shared reliance on diving for feeding. White-backed Ducks eat vegetable matter, especially waterlily seeds, collected from the bottom of shallow wetlands. Clark (1969, Wildfowl 20: 71–74) reported that dive durations increase with water depth, lasting 12 to 14 seconds in water 0.3 metres deep, 15 to 20 seconds in water 0.6 to 0.9 metres deep, and 25 to 30 seconds in water approximately two metres deep. Recovery intervals between dives range from four to 12 seconds, increasing with dive duration and depth, giving a dive efficiency (the ratio of dive duration to recovery period) in the order of 2 to 3.
Cette histoire est tirée de l'édition May/June 2018 de African Birdlife.
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