Determining the Age of Rock Ptarmigan in Alaska and Scotland
Weeden RB and Watson A. 1967. Determining the Age of Rock Ptarmigan in Alaska and Scotland. The Journal of Wildlife Management. 31(4):825-826
Up to the age of 12-15 months, when young rock ptarmigan (Lagopus mutus) shed their first set of white primaries, they can be distinguished from older birds by primary coloration. On old birds the second outermost primary has the same amount or less dark pigment than the third outermost primary; younger birds have more pigment on the second outermost. The method was tested with 607 banded or dissected birds in Alaska and Scotland, and was about 98 percent accurate for all sex and age groups combined.
- Type
- Journal Article
- Authors
- Weeden, Robert; Watson, Adam
- Units
- ARCN , CAKN , DENA , GAAR , WRST , YUCH
- Keywords
- aging, Birds, Grouse, Lagopus mutus, Plumage