oily fur

Question
I have a Syrian hamster and it has started to get very oily behind his ears hes just old enough to tell his gender and he also started making a hissing noise at me today an answer would be great thanks  

Answer
Dear Bianca,
thank you for your question.
Do you offer a sand bath? Syrian hamsters don't need it as much as dwarfs, but clearly enjoy it and especially the longhaired breeds should have one. I recommend seeing a vet with him to rule out and medical problems, like fungal infection (although this usually looks different).

The hissing is a sign that the hamster felt threatened by you, he would probably bite when you touch him after he gave you that warning. When he's already tane, you may just have scared him by accident. If you stil need to tame him, have a lot of patience and lt them hamster come to you instead of trying to handle him, which may just make him afraid of you.
I hope I was of some help to you
Jennifer