Eye-ring coloration is not a reliable indicator for aging Mangrove Cuckoos (Coccyzus minor)
Soft-part coloration can be a useful method for determining the age of a bird. For example, hatch-year and early second-year Mangrove Cuckoos (Coccyzus minor) are supposedly distinguishable from older birds based on the presence of a dusky gray eye-ring; individuals gain a vivid yellow eye-ring in t...
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Published in | The Wilson journal of ornithology Vol. 129; no. 1; pp. 163 - 165 |
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Main Authors | , |
Format | Journal Article |
Language | English |
Published |
Fort Collins
The Wilson Ornithological Society
01.03.2017
Wilson Ornithological Society |
Subjects | |
Online Access | Get full text |
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Summary: | Soft-part coloration can be a useful method for determining the age of a bird. For example, hatch-year and early second-year Mangrove Cuckoos (Coccyzus minor) are supposedly distinguishable from older birds based on the presence of a dusky gray eye-ring; individuals gain a vivid yellow eye-ring in their second year of life that they retain for the rest of adulthood. However, observational data collected on banded Mangrove Cuckoos throughout the year indicate that eye-ring coloration varies seasonally rather than with age. We captured and banded two individuals in early spring, each with a yellow eye-ring. Re-sightings of these individuals later in the spring and early summer revealed that the eye-ring had changed to a dusky gray color. Subsequent re-sightings of these individuals again in the fall and winter revealed that both once again had a yellow eye ring. In reviewing photographs and notes taken during observation of marked and unmarked individuals, we determined that this pattern—a yellow eye-ring during late summer, fall, and winter (nonbreeding) and a dusky-gray eye-ring during spring and early summer (breeding)—was consistent across individuals in the population in Florida that we studied. |
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ISSN: | 1559-4491 1938-5447 |
DOI: | 10.1676/1559-4491-129.1.163 |