Tuesday, July 7, 2015

American Avocet

Late last March, we raced across southern Louisiana so that we might have time to explore the Avery Island gardens. Along the way we came upon this flock of American Avocets. A quick guess suggests that only about 15% of these birds retain their winter (basic) plumage, with little or no trace of orange on the heads or breasts. The others are well on the way to their spectacular breeding (alternate) plumage. This percentage of winter-plumaged birds may be a bit higher than expected, as Ackerman et al. (2013) report almost 90% should be in full breeding plumage by early March.

Avocet sexes are identified by the bill shape—shorter and more strongly up-curved on the female. Unfortunately, all but one of these birds (the second to the left) are sleeping with their bills tucked under their scapulars. Without bills to compare, separating avocet sexes can be a challenge.

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