Many nestlings have what looks like a tongue disease. I have seen this over many seasons and adults, later recapped, don't have it. The front of the tongue is yellowed, see photo. What is this? Is it normal ?
Am I understanding correctly that you've seen this in nestlings you've banded, and you've later caught the same birds as adults but the tongues have returned to normal coloration?
Am I understanding correctly that you've seen this in nestlings you've banded, and you've later caught the same birds as adults but the tongues have returned to normal coloration?