Gerbils (a.k.a. jirds) became popular as pets in the United States around 1950-1960 after they began to be used more commonly in medical research centers. Unless you have an exotic pet gerbil, chances are high that you have a Mongolian gerbil. Most pet gerbils are related to the original sample of gerbils shipped to the US for research. Some of the gerbils escaped and have made homes in the desert areas of the States, particularly in Texas. Some places, like California, have outlawed gerbils as pets fearing they will escape and establish a family colony.


A gerbil's diet mainly consists of grain and seed. They also eat (fresh) fruits and vegetables, but don't feed them too much because it can give them diarrhea. My gerbil guide says they will also eat invertebrates (worms, insects, etc.), carrion, and babies of other small rodents; however, I have not been able to get mine to eat bugs.
If you plan to keep gerbils of both genders, you will need at least two cages. If you want to breed them, you should do so selectively instead of letting nature run its course. The only one who decides who will mate should be the owner/breeder. This means you will want to keep them separated by gender. If you don't want to breed them, always keep them separated; gerbils can successfully mate in a matter of minutes. If you turn a gerbil on its back, you can tell if it's a male or female if you see a penis and pair of testicles or not. It looks like a round pink nubbin. It's that simple.
The best way to keep a gerbil is in a glass aquarium, 10 gallon is recommended, but bigger is better. Avoid plastic at all costs because they can chew through it and will scratch at it constantly. The tank will need a water bottle, a ceramic food bowl (remember, avoid plastic), a place to hide, bedding, and toys.
For their home, you can purchase a small rodent house at a pet store. However, they tend to be made of wood or plastic which the gerbils will eventually chew into oblivion. Your best bet is to break a hole big enough for a gerbil to crawl in and out of in a flower pot that will fit in the tank. File down the edges of the hole so your gerbil won't injure itself and voila! Also, I took the risk of putting treated wood (in the snakes/reptilian section of pet stores) in the cage and she hasn't chewed on it yet.
For bedding, avoid anything with cedar in it because it is toxic to the poor little gerbils. Aspen and pine come highly recommended. I use aspen pellets for the floor and give the gerbils toilet paper to make their beds as needed since you don't have to change the pellets as often as completely shredded bedding. Remember to keep empty toilet paper tubes because these are fun for gerbils to play in and chew on. Pulp and fiber are allegedly more absorbent than wood shavings.
Toys include things such as chew toys and exercise wheels, but be careful to purchase one with a guard lest you want a tailless gerbil. I cut small branches from my trees and they seem to like to chew on that (and it's free for me). If they don't have anything to chew on, they can become destructive (chewing up the water bottle, or their homes). They need to chew to keep their teeth at a reasonable length.

The fun part: Breeding

The estrus period, when she is in "heat," is "four days in gerbils and happens about every six days" (42). The best way to introduce gerbils is to put the two in the same cage with a wire mesh/screen to separate them. There is always the chance that they will not pair nicely and become hostile; that's why it's necessary for them to get used to the other's scent. I found this to be a pain in the butt, so I swapped the gerbils and their cages. I put the female in the male cage and vice versa. They had a fun time marking/re-scenting everything. Then I swapped them again after about 24 hrs. By this time, they had adjusted to each other's scent, so when I put them together they did just fine.
If the male wants to mate with a female, he'll put his nose up to her butt. After a couple of tries, if the female is receptive to the attention, she'll stick her butt in the air. A male gerbil can finish off one round of mating in about 15 seconds (guestimate). Typically, gerbils will go through several rounds in a matter of minutes. I'm told a male needs to mate at least 40 times to successfully impregnate a female. So, it's best to leave the two alone for a day or so. Assuming she is pregnant, separate the two again. If she is not noticeably fatter within a week, let them mate again.
The gestation period for a gerbil is about 25 days. After she has given birth, she can have a second round of babies. Gerbils can mate post partum, meaning females store the sperm and have delayed implantation once the babies have been weaned. This is why you need to separate her again; a second round will stress her body. She can have up to 10 babies, "4-7 being more likely" (42).

Approximation of maturing events:

Full fur - 1 week
Ears open - 13/14 days
Eyes open - 16-18 days
Eating solid foods - 16 days
Weaning - 21 days (Be sure they are fully weaned before separating.)
Reproductive capabilities - 8 weeks (though ample time for females to mature should be given, otherwise you risk cannibalization of babies.)

Color chart for gerbils

(Source: http://www.geocities.com/Heartland/Park/6961/)
Color 	A	P	C	G	E
Dark Tailed
White	      **	P*	chch	**	E*
Champagne	**	P*	CC	G*	efef
Schimmel	**	P*	CC	G*	efef
Pink Eyed
White	      **	pp	chch	**	E*
(Most common)
Agouti	A*	P*	C*	G*	E*
Dark Eyed
Honey	      A*	P*	C*	G*	ee
Aghouti	A*	P*	cbcb	G*	E*
Gray Aghouti
            A*	P*	C*	gg	E*
Polar Fox	A*	P*	C*	gg	ee
Colorpoint Gray Agouti
	      A*	P*	cbcb	gg	E*
Yellow Fox	A*	pp	C*	G*	ee
Argente Golden	
            A*	pp	CC	G*	E*
Apricot/Red Fox	
            A*	pp	C*	gg	ee
Ivory Cream	A*	pp	CC	gg	E*
Black	      aa	P*	C*	G*	E*
Nutmeg	aa	P*	C*	G*	ee
Burmese	aa	P*	cbcb	G*	E*
Siamese	aa	P*	cbch	G*	E*
Silver Nutmeg	
            aa	P*	C*	gg	ee
Slate	      aa	P*	C*	gg	E*
Colorpoint Slate	
            aa	P*	cbcb	gg	E*
Light Colorpoint Slate	
            aa	P*	cbch	gg	E*
Argente Nutmeg	
            aa	pp	C*	G*	ee
Lilac	      aa	pp	CC	G*	E*
Dove	      aa	pp	Cch	G*	E*
Ruby Eyed White	
            aa	pp	C*	gg	E*


Gerbils are very social creatures. They have a shorter lifespan if they live alone. They live 3 years with other gerbils, and about 1 year alone. Males with males get along less often than females with females. The way a gerbil shows social dominance/friendship is by grooming the other gerbils.
Gerbils are allegedly nocturnal, but they are up at all hours of the day and night.
Gerbils are the third most popular small pet rodent. Hamsters and mice being the top two.
Literary source: The Guide to Owning a Gerbil, Perry Putman. T.F.H. Publications.