Aggression between gerbils
Gerbils are generally more active during twilight hours.
Thumping is an alert call to inform the colony of danger.
Barbering is a type of over-grooming with many causes.
A declan is when a bonded pair of gerbils need to be separated due to an attack.
Gerbils bite out of fear or pain.
Please see Declanning
Nipping is a pinch that doesn't break the skin