[Katarina]

It sounds like the mite that are common on house bird pets like budgies - I had them in the house. they are pale gray when unfed, but after a feed they turn red and then black. they lay eggs in crevices and ridges of wood so you'll have to sterilize the whole of the cage really well and throw or bake all of your wooden stuff otherwise after treatment the babies will hatch and you'll have to go through the treatment again. try covering the cage with a cloth and you'll soon see them on it. Nasty things - I had to throw away the cabinet my bird cage was on as the eggs were in the wood. if left untreated, it causes anemia and infection, so please go to the vet soon!