There are several types of "pocket pets" that pet buyers have to choose from, among them are gerbils, mice, and hamsters. When choosing your next small furry friend, a few guidelines about care and differences between species can help insure the best choice!
Gerbils are one of the best small pets to own, they are very easy to care for and are not nocturnal, so will be active on and off throughout the day. Gerbils originate from Mongolia where they live in semi-deserts and steppes. They don't drink as much as other species, so comparatively little waste, and less odor! Gerbils should be kept in same-sex pairs, they are very social. Cages will only need cleaning every 2-3 wks, and they should have very little to no smell. Gerbils are very interactive pets, they are intelligent, fun, and curious. When tamed, they enjoy coming out for playtime and can be taught to be "shoulder-sitters", climbing their human's arm and sitting/staying on the shoulders for short periods of time. They are easy to provide with tank accessories as every gerbil has fun with the cardboard box or the beloved toilet paper and paper towel tubes! Gerbils can live up to 3 years (2+ is considered senior), and sometimes will reach 4 or 5.
See Gerbil Care for more info on gerbils.
My first rodent pet as a child was a long-haired (Teddy Bear) hamster. :) Hammies are great pets, they are fun, entertaining little guys! Hamster (from the German word "hamstern) means hoarder; understandable once you see a hammie "pouching"...stuffing its cheek pouches full of food! :P Several varieties are available for pet lovers...
1) Syrian - Syrian hamsters are the large type often seen in pet stores, reaching a lengh of 6-7 inches, and living up to 3 years. They are often sold in pet stores under different names such as Teddy Bear, Golden, or Black Bear hamsters. Syrians are solitary and must be kept singly; once they start to mature they don't like one another's company and will fight. Syrians come in over 40 colors, 3 coat types, and also a few patterns. They are nocturnal, sleeping during the day and more active at night. Best to give them a roomy cage like a 20 gallon long tank, or a multi-leveled "wire" type pet cage. They will have some smell, so clean cage as needed and provide a wheel, hiding places for sleeping, etc
2) Dwarf Hamsters - Also available in the pet trade are 4 types of Dwarf hamsters. Dwarfs vary from 3-5 inches in length and live on average about 2 years. These guys are small and very cute, but quicker moving than the larger Syrian.
a) Campbell's Russian or Siberian - Campbell's Russian or Siberian is the most common dwarf hamster. They come in many colors, i.e. opal, argente, blue, chocolate, black-eyed argente, beige, black, and more. Also found with spotting patterns like mottled, and either normal coat or satin.
b) Winter White Russian - The Winter White Russian Dwarf (sometimes also called Siberian), is similiar to the Campbell but with 3 dorsal stripes. The Winter White hamster has a dark grey colored coat most of the year but changes to a white coat which would have been a winter camouflage in the wild; the coat change is in response to shorter days, i.e. decreased photo period as opposed to temps. In captivity the amount to which the coat lightens tends to vary.
c) Chinese Dwarf - Chinese Dwarf hamsters are a third, less common type of hammie, they are harder to breed/raise in captivity; they are called the rat-like hamster on account of longer tails than other dwarfs, short noses, and thin bodies.
d) Roborovski (Robo) - Lastly, is the Roborovski or Robo hamster, the smallest variety, and excessively adorable, but VERY fast little guys, not the best for a cuddly pet or perhaps small children. :)
Caging for Dwarf Hammies - Dwarf hamsters are social and can be kept in pairs. They sometimes tend to "squabble" but unless blood is drawn, little bouts or fights are just apart of normal interaction. Do be sure that cage space is sufficient, as they would fight more if competing for space/food etc. Dwarfs can be kept in the "colorful" plastic Habitrail cages with tubes which some people find fun (though they are harder to clean) or a 10 gallon tank can be used for a pair. They love wheels like the syrian, and lots of little places to hide and sleep. Carefresh bedding is nice for dwarfs so they can fluff it out and use for nest building.
Hamster Temperment - Hamsters can easily be found in pet stores, but when possible, they are best bought from a breeder who socializes and hand-tames their pups. Syrians can be nippy or unsociable with people if not used to being handled and the dwarfs will tend to be scared or skittish, again, if they were not handled as babies. Hammies also have poor eyesight; when handling, let them know you're there as opposed to swooping down to pick them up or waking them suddenly from sleeping; they are more likely to nip if startled, or if your hands smell like PB ;) mmmm!
Ah, the fancy mouse! So cute! Often seen in pet stores is the albino, pink eyed white variety, but mice come in many, many colors and several coat types in addition to standard short hair... angora (long-haired), satin, rex, and texel are a few. Fancy mice are short-lived, about 1 to 2 years. They are known for being smelly little critters (especially males :) so be prepared for cleaning cage every week, or can go bit longer if you don't mind the smell. Because of need for frequent cleaning, tanks are really the most convenient/easy option for housing mice. Mice should have a wheel to play on with hiding spots, and other cage accessorizes for entertainment. They enjoy climbing little wooden ladders/ramps, etc. Check the bird section of a petstore for some toy ideas.
Male vs. Female - Girl mice are social and need to be kept in same-sex pairs or "colonies" of 3, 4 etc. Mature males should be kept singly, they will fight with other adult males. However note that single boy mice can make awesome pets, as they won't have other mice to focus on and will be more ready for human attention and interaction (teach them tricks!). Do be sure to NOT get male with female pair, (pet stores often goof on who's boy and girl!) as mice produce prolifically, with the possibility of VERY large litters. Don't try to breed mice "just for fun"...you will quickly be overwhelmed.
Temperment - Mice do tend to be shy and skittish...they ARE very small...and human hands can be big and scary ;) Nothing like having a friendly fancy mouse though... having that little tiny pet come right onto your offered hand is so fun! If you want tame, friendly, mice, best bet is to find a reputable breeder who breeds pet mice, and socializes/holds the mice from birth.