Thankfully that looks very superficial but as birds have very thin skin it has gone through.
Now if it was that recent, then we'd not see signs of infection yet but I want you to keep a close eye out for that. Cat saliva is full of bacteria and abscesses/infection are really common in these situations. And that is our biggest enemy here for Gizmo. Of course, at the moment we need to make sure that is not actively bleeding. If it is, he needs to be caught and pressure applied to stop the bleeding. Cornflour or flour can be used just as a means to help clot the bleed quicker if it isn't stopped with pressure.
Otherwise, for the next few days, we need to keep things calm and quiet so that he isn't overly stressed. The wound can be flushed this 2-3 times daily with a mild antiseptic (ie dilute betadine, chlorohexidine, or salt water). Afterwards, pat the area dry and apply an OTC antibiotic cream. We of course need to make sure he cannot reach the wound, else he may need a little wrap. If it closes up without issue then we are happy. But any pus, swelling, discomfort or redness and we'd want the local vet to see him as often these needs antibiotics (even if not needing to be stitched).
Just in case you do need an avian vet and do not have one already, you can check where you can find one at near you at AAV (http://www.aav.org/search/), Avian web(http://www.beautyofbirds.com/recommendedvets.htm) or Birdsnway(http://www.birdsnways.com/birds/vets.htm).
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