Final answer:
Wing clipping is not used on gerbils since it is a method applied to birds; gerbils are small rodents, and other identification methods like microchipping and ear tagging are suitable for them.
Step-by-step explanation:
The identification method that is not usually used on gerbils is wing clipping. Wing clipping is a practice used on birds to prevent them from flying and is not applicable to gerbils, which are small rodents. Other identification methods, such as microchip implantation, ear tagging, and tail tattooing, can be used in mammals like gerbils to keep track of individuals for scientific research or pet ownership purposes. While the mark and recapture method is often employed for studying animal populations, it wouldn't involve physically altering the animals as in the case of wing clipping.
The identification method that is not usually used on gerbils is wing clipping. Wing clipping is a method commonly used to restrict the flight of birds, but it is not suitable for gerbils as they do not have wings.
Gerbils are usually identified using methods such as microchip implantation, ear tagging, or tail tattooing. Microchip implantation involves placing a small electronic chip under the skin, which can be scanned to retrieve the gerbil's identification information. Ear tagging involves attaching small tags to the gerbil's ear, similar to how livestock are tagged for identification. Tail tattooing involves marking the gerbil's tail with a unique pattern or number.