Why has my gerbil died?

Question
One out of my pair of 7 week old female gerbils has just died quite suddenly. Both gerbils seemed healthy just last night though this morning one seemed quite lethargic with slightly laboured breathing. By mid afternoon she had died. My other gerbil seems perfectly healthy still. I wonder if you might be able to tell me why she died and whether the other one is likely to suffer the same thing? Also, would it still be early enough at this stage to introduce another gerbil to keep the other company?  

Answer
Hi Jane,

This exact situation happened to me recently, with my two gerbils.  One suddenly became ill and died within 24 hours.  The other seemed fine, if a bit lonely, but he too began displaying the same symptoms (which were very vague - listlessness and not eating or drinking, no diarrhea) and died 10 days after his brother died.  I still have no idea why they died, as their cage was always kept clean and I used Aspen bedding.  They were not as young as yours, however; they were 2 1/2 years old.  Honestly, you may have to contact a vet.  I had a problem with that, as I live in a small town with a vet who is used to treating dogs, cats, cows, and horses, not small animals.  However, you may have a vet near you who knows how to treat small animals.

I would advise you to wait about a week before introducing your gerbil to another one of the same sex.  Yours is still young enough, though.  Just make sure the gerbil you get is between the ages of 6 and 8 weeks.  And when you introduce them, use the split-cage method (from the American Gerbil Society):

"Split Cage Method:

Gerbils are very territorial, and will be aggressive towards other unfamiliar gerbils. Ideally, you should pick out two gerbils that are already living together, or that are between six and eight weeks old. That way you shouldn't have trouble introducing them. However, if one or both gerbils are over eight weeks old a Split Cage Introduction is recommended.

A twenty-gallon aquarium divided down the middle for a Split Tank Introduction. You will need a cage or tank that can be divided down the middle. There are some commercial cages that can be purchased that are divided in two, but these can be difficult to find. To make a split cage, simply use one of your tanks and stiff, heavy 1/4" to 1/2" hardware cloth with. Place the dividers from corner to corner. (This makes it more secure.) Be sure that the divider fits in firmly! Gerbil will try to crawl under, over, or around to get to the strange gerbil on the other side. Watch the gerbils as much as possible until you are convinced that your split cage is secure.


Place one gerbil on either side of the divider. The whole concept behind the split cage intro is to give the gerbils time to become use to each other's scent, while preventing fights.  
Four to five time a day carefully switch the gerbils to opposite sides of the split cage.
Continue this routine for one week.
Now remove the divider. Wear heavy gloves in case they should fight.
Plan to watch them carefully for five to six hours, or longer. (Removing the divider is best done on a day that you have at home.) Do not leave them unwatched together until they sleep in the same nest. If you need to leave them replace the divider.
If the introduction has gone well they will be use to each other's scent, and no fight will break out.
If a fight breaks out separate them immediately, and start all over again. "Boxing" is okay, but rolling in a ball fight or one springing in the air as the other chases are signs of serious fighting.
You know that they have accepted each other when they settle down to grooming and are sleeping together in the same nest.
WARNING: Under no circumstances should you ever try to introduce a gerbil to an established group. Split cage introductions work only for two lone gerbils. Gerbils that have been separated for more than a day need to be gradually reintroduced using a split cage."

I wish I could've been more help, but I'm afraid I'm just as perplexed as you are when it comes to the sudden death of gerbils.  The only thing I can think of is that perhaps your gerbil (and possibly mine) had strokes.  This is most common in older gerbils, but it can occur in younger ones, too.  This just doesn't sound right, though, so like I said, try to consult a vet.

If you have any other questions, please feel free to ask.

Kelly