Hi All, New poster here, but have learned a lot from reading for months. We have nine baby white and fawn runner ducks who arrived in strong fluffy yellow condition. After about a week now a few of them look fine, but most of them have a crusty brown look around their heads. Its dry and stiff like hairspray..... Any ideas if this is bad and/or what we should do about it? First photo shows the issue, second photo is fine duck. Thanks for you help!