Blue-Tongued Skink’s Loss Of Appetite

My blue tongue skink has not been moving much lately and does not want to eat. I'm not sure whether he is hibernating because its only early autumn and the temperature has not dropped significantly (about 2 degrees celsius). I have tried feeding him his favorite meat but sometimes he seems to regurgitate it. He seems to be taking big breaths of air every so often and at at times he just doesn't seem to be breathing at all.

This kind of behavior in reptiles is usually due to either shedding or brumation (hibernation). Since you probably know how you usually acts when shedding this might possibly be ruled out. Brumation occurs naturally in the wild as the animals hibernate over the winter months. It is triggered by both a drop in temperature and a reduction in daylight hours. If they go in to this state then they will stop eating (and should not be fed) as otherwise they will have rotting food in there bellies during the 3-4 month brumation. Brumation is not necessary in captivity unless you are planning to breed. You can "cure" problems associated with brumation by increasing the daylight hours and temperature of his habitat so that it is constant all year round. If this action fails to induce his normal behavior you should take him to see a specialist reptile vet who can advise you further.