There's no specific amount they "should" chew, but it's normal for them to be chewing most of the time. You should provide them with plenty of safe chew toys like:
* Wooden chew toys: These are great for gnawing and help wear down their teeth.
* Cardboard tubes: These are often a favorite for gerbils and easy to find.
* Natural chews: Branches from safe trees (apple, willow, etc.) can be a fun and healthy option.
Signs of excessive chewing:
* Chewing on cage bars: This could indicate boredom or lack of appropriate chew toys.
* Chewing on furniture: This is usually a sign of stress or boredom and needs to be addressed.
* Chewing on their own tails or feet: This could be a sign of a medical condition or stress, and you should consult a vet.
If you are concerned about your gerbil's chewing habits, it's best to consult with a veterinarian. They can help determine if the chewing is normal or a sign of a problem.