Identification and Registration

Community-Based Solutions to Managing Companion Animal Populations

Companion animals should have at least one form of permanent identification. Ideally, all cats and dogs would have a microchip which is registered in a database. Additionally, non-permanent forms of ID such as pet ID tags on collars are encouraged. Companion animals with ID are much more easily returned to their owners and multiple forms of ID increase the chance of a successful return of the animal. There are a variety of types of identification including permanent and non-permanent methods.

Permanent Identification

Permanent types of identification commonly available to pet owners are microchips or tattoos. While these can be used to locate the owner of a lost pet, they require the use of a database and third party to retrieve the owner’s information. Their primary function is to serve as permanent identification and concrete proof of ownership. These are helpful as a backup method to identify an animal in case they have lost their collar or tag.

    1. Microchips
      Microchips are a small implant, about the size of a grain of rice, embedded under the  skin of an animal using a large needle. The procedure is minimally painful and can be performed during a routine vet visit. The chip contains a unique series of numbers that act as a serial number specific to that animal. A scanner is required to display the unique identifying code which can be traced back to the owner with the use of a database provided by the chip company. Most vet clinics and animal shelters have scanners and can scan found animals to assist with owner identification.When an animal is scanned at a vet office or animal shelter, the owner information can be verified. Thereby, a finder can ensure they are returning the animal to the rightful owner. Microchips provide irrefutable proof of ownership and cannot be removed.Microchip Pros:

      • Long lasting, permanent ID
      • Can be inserted without sedation
      • Usually comes with a tag indicating the animal is microchipped (Microchips can migrate from their injection site. A microchip tag gives the message that it is there and may have migrated).

      Microchip Cons:

      • Require a chip scanner and database to contact owner
    2. Tattoos
      In the past, tattoos were commonly used by vet offices, animal shelters, rescue groups, and breeders to track and identify animals. Tattoo popularity has declined as more people choose to use microchips instead. They do still serve the purpose of permanent identification. If an animal with a tattoo is found, the tattoo can be traced to the vet clinic that created it, who in turn can contact the owner of the animal.Tattoo Pros:

      • One time application/permanent ID
      • Readable by anyone (without the use of technology) if animal is not fractious or aggressive

      Tattoo Cons:

      • Hidden by hair or fade over time making them difficult to read
      • Requires the animal to be sedated to tattoo
      • Unreadable if animal is fractious or aggressive
      • Need use of database to track to the owner

Non-Permanent Identification

Microchips and tattoos are an excellent form of permanent ID, should an animal become lost without a collar or tags on. However, ID tags provide instant access to an owner’s contact information. They do not require any third-party database for contact, so it is often the quickest and most effective method in reuniting pets with owners.

    1. Collar & ID Tag
      A standard collar represents a worldwide, recognized symbol for an “owned” animal. Coupled with the owner’s information attached with a tag it is a powerful reunion tool for lost pets and their owners.ID Tags Pros:

      • Provides instant identification of a pet
      • ID tags are easily readable by anyone without the use of technology
      • They are readily available, inexpensive, and fully customizable

      ID Tags Cons:

      • Potential safety risk as they can become hooked or caught
      • Can become detached and lost
      • Several tags together can become bulky and can be noisy from the jingle of metal on metal

      Ideally, a pet should wear a collar with ID all the time. ID tags have a limited amount of space available to include important information. At a minimum, the tag should include:

      • Pet’s name
      • One or two (current) phone numbers
      • A personal message like “I am microchipped” or “Call my mom” or “I’m friendly”
      • Special needs (Medical condition or treatments)

      One single method of identification, whether it be a tag, customized collar, tattoo, or microchip is good, but a combination or two or more is better. Each has their unique benefits, but their drawbacks are relatively minor compared to not having a pet returned due to lack of identification. Identification is only as good as the information provided and should always be up to date.

    2. Registration
      Typically, pet registration requirements are dictated by the municipality, in conjunction with any associated pet bylaws. A licensing program is commonly used for the registration of a pet owner. Usually a licence identifying number is issued to the owner, along with a tag bearing the identifier and a contact number for the registering organization. If a stray pet is found with the tag, a person can call the registering organization to get current contact information for the animal’s owner.Licensing may be used when certain criteria have to be fulfilled prior to pet ownership and might require additional actions on the owner’s part, such as ensuring that the animal is microchipped, has a current rabies vaccination and/or is spayed/neutered.In many jurisdictions a fee must be paid. Registration or licensing fees can be charged (a one-time fee or payment each year) in order to provide funds for other areas of the management program. Although care needs to be taken to balance potential income against enforcement, if fees are too high owners may try to avoid registration. Differential fee scales can be used as an incentive for sterilization, encouraging owners to keep only a small number of animals and discouraging breeding or hoarding. Licences typically must be renewed annually.Mandatory registration and identification can help the practical problems faced by impound facilities and shelters. When a stray animal is quickly identified, it can be returned to its owner without delay. If not identified, it is by definition ‘un-owned’ and the facility can implement its policies without the delay of waiting for an owner to come forward.The most effective way of clearly connecting an owner with his or her animal is to use registration and identification together. This should encourage a sense of responsibility in the owner as the animal becomes identifiable as his/her own. Registration/identification is an important tool for reuniting lost animals with owners and can be a strong foundation for enforcement of legislation (including abandonment legislation and mandatory regular rabies vaccinations).Furthermore, developing communication, education and advocacy messaging that urges guardians to have their animals properly identified is encouraged. It is also encouraged for municipalities to enact bylaws that make companion animal identification mandatory and to hold low-cost microchip clinics to make ID accessible to all.


A Municipal Approach to a Self-Sustaining Community Animal Welfare & Enhanced License Compliance Program from (2014).

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