Effect of heat and singeing on stable hydrogen isotope ratios of bird feathers and implications for their use in determining geographic origin.

Limited singeing that did not dramatically alter the feather morphology did not substantially affect δ2 H values of feathers from these songbirds. However, higher temperatures induced charring and reduced δ2 H values. Therefore, severely charred feathers should be avoided when selecting feathers for δ2 H-based assessment of geographic origin.