A reputable breeder or a pet shop employee should be able to sex the hamsters for you.
Do not try to put a young hamster in with an older hamster. The older hamster will be protective of its territory and the hamsters will likely fight.
Also, keep in mind that if you hold one hamster and then introduce it to a cage with a hamster you have not yet held, then the other hamster may reject that hamster based on the unfamiliar scent. Hold both hamsters before you introduce them to each other so that your scent will be on both of them.
If you choose a glass aquarium, then place a mesh lid on top of it to allow air to flow through since no air will be able to get through the sides.
If you don’t have two extra cages to place the hamster in temporarily, then put each hamster into a shoe box or hamster ball. However, don’t keep them in these temporary enclosures for more than an hour.
Only use bedding that is made from plant-based fibers or cellulose. Never use wood shavings, newspaper, cat litter, corn cobs, or any type of scented bedding. [5] X Research source Do not try to reuse the old bedding! Throw it out and replace it with new bedding every time you clean your hamster’s cage.
Provide specially made hamster food in dishes for your hamsters to graze on and also place fresh slices of fruit and veggies into the cage for them daily, such as carrots, apples, pears, or broccoli. Never give your hamster onions, leeks, garlic, chives, lettuce oranges, or raw potatoes because it can make them very sick!
Hamsters love to run! If possible, get two hamster wheels so that each of your hamsters will be able to run whenever they like. [8] X Research source
You may also be able to purchase a special divider insert for the hamster cage at your local pet store.
Pay attention to when the hamsters normally sleep and wake so that you will know when to attempt the introduction.
For example, you could close the curtains to block out some of the sunlight, or turn off half the lights in the room.
You may also use a plastic bin or shoebox to make the introduction. Place the divider down the center of the bin and put adequate bedding, food, and water on each side of the divider. If both hamsters are new, place 1 of the hamsters into the cage first, then add the other a minute later.
If the hamsters continue to show signs of aggression, you may have to house them separately.
Even if both hamsters seem to be getting along well, check them both for bites regularly. If you notice bites on 1 or both hamsters, separate them immediately. [12] X Research source Be prepared to keep your hamsters separated in 2 different cages if they don’t get along.
