I recently bought a rat from a pet shop, and for the first few days it seemed fine, but now it's constantly hissing and attacking my hand whenever I try to pet it. Maybe it's stressed from the move, or is it just its temperament? Are there ways to calm it down and tame it?
Stress from moving is a common cause, especially if the rat is very young. In pet stores they're often kept in poor conditions, so the first few weeks in a new home the animal can be scared and aggressive in self-defense. Give it time to adjust - keep it in the cage for a week or two without stress, don't stick your hands in unnecessarily. Gradually the rat will understand that you're not a threat.
When its behavior settles down a bit, start taming it slowly: just put a treat next to you and let the rat get used to the smell of your hands. Then offer food right from your palm. Hissing and bite attempts are a weak attack; if it's actually biting, it means it's in a panic. Don't make sudden movements, speak quietly, don't grab it. Gradual conditioning with snacks (peanuts, dried fruit) usually works even with nervous individuals.
If the rat is healthy and otherwise behaving normally, just give it time and patience. Most of them gradually become affectionate. But if the aggression doesn't let up over months, maybe it's not quite a domestic breed or there's a health issue - get it checked out by a vet.
Time and patience are the main cure, but there's a specific way to speed things up. Try feeding the rat from your hand - literally place a treat (raisins, a banana slice) on your palm and just sit nearby without making sudden movements. The rat will gradually understand that your hand is a source of food, not a threat. Hissing and bite attempts in the first few days after bringing it home from the pet shop are almost always a defensive reaction, not a sign of innate aggression.
When I was helping a friend set up a terrarium for his rat, it also acted aggressively for the first two weeks. We just put a glove (clean, with no laundry smell) in the cage and left it there - the animal got used to the human scent. At the same time, we offered treats through the cage bars. After about a month and a half, the rat was already jumping on his shoulder, completely tame. The key is not to shove your hands into the cage abruptly or grab it by force, otherwise the fear will just get worse.
Also make sure the cage is spacious enough, with hiding spots and toys. A bored and scared rat bites much more readily than one that's busy and feels safe. And yeah, young rats from pet shops often get scared - it's not their fault.
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