Hamster
Cheek pouches that stretch back to the shoulders, and a night shift: a hamster will run miles on a wheel while the house is asleep. Syrians live alone.
Overview
A Syrian hamster is a solitary animal and that is the most important thing about keeping one. In the wild the adults live in lone burrows, and both sexes are strongly territorial with their own kind, with females often the more aggressive of the two. Two Syrians in a cage is not company, it is a fight waiting to happen.
The cheek pouches are the other thing worth knowing. They open inside the lips and reach back past the shoulders, and a full load more than doubles the width of the animal's head and shoulders, which is how a hamster moves a night's foraging back to the nest in one trip. They live two to three years, and they are properly nocturnal, so a cage in a bedroom means a wheel at three in the morning.
Temperament
Tame easily and bite when startled, which is usually the same thing seen from two ends. A hamster woken up in daylight and lifted out of its nest is a hamster reacting to being grabbed while asleep.
Let it come out on its own schedule and it becomes a different animal. Evening is the time to handle one. Dwarf species are more tolerant of company than Syrians, though even they can fall out permanently and need separating.
Care and grooming
A plain seed and pellet mix, and a check of the pouches if you ever see swelling that does not go down, since impacted pouches happen and need a vet.
They hoard, and clearing out the whole store during a clean is stressful for them, so leave part of it. Wet tail is the serious illness to know: sudden diarrhoea in a young hamster is an emergency rather than something to monitor overnight.
Living and exercise
Floor area and deep bedding beat a tall cage with tubes. A hamster burrows, and six inches or more of bedding lets it, which is the closest thing to real enrichment the species has.
The wheel has to be big enough that the animal runs with a straight back, and solid rather than barred. A hamster running curved is being harmed by the thing that is supposed to be exercise.
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