| Titre : | Eye-ring coloration is not a reliable indicator for aging Mangrove Cuckoos (Coccyzus minor) (2017) |
| Auteurs : | Rachel D. Frieze, Auteur ; John D. Lloyd, Auteur |
| Type de document : | Article |
| Dans : | Wilson Journal of Ornithology (The) (129(1) March, 2017) |
| Article en page(s) : | 163-165 |
| Résumé : | ABSTRACT 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. |
| En ligne : | http://dx.doi.org/10.1676/1559-4491-129.1.163 |



