Coded Wire Tags are tiny, and because they are usually injected into cartilage or muscle below the skin, they are rarely visible. However, their presence can be electronically detected using Coded Wire Tag detectors.
When do you need a detector?
Detectors are used at four stages in most Coded Wire Tag projects:
- During tagging, you won’t be able to see if a tag has been injected, so you will need a detector to verify successful implantation. If you are using a Mark IV Injector, a common choice is to pair it with the Quality Control Device to verify tag injection. However, this can also be done using a V-Detector or Wand.
- After tagging, but before release, you will need a detector to measure tag retention rates. A V-Detector is an excellent tool for this, and a wand detector can also be a good choice.
- At recapture, you will need a detector to sort tagged and untagged animals unless they can be distinguished by a secondary tag or mark (eg a fin clip). The most suitable detector depends on the application. Tunnel detectors are a good choice for high volume sorting such as at hatcheries or processing plants. The T-Wand detectors is rugged and portable for field sampling. In some cases, it can be used to identify the specific body location of a tag when the body location is used as a batch code. V-Detectors are a good choice when they can be placed on a stable surface.
- Once tagged animals have been identified, you will need a Coded Wire Tag detector during the dissection process to quickly locate and remove tags. A V-Detector is the preferred tool for this job.
Available detectors
We offer four types of Coded Wire Tag detectors: T-Wand (specifications (pdf), how-to video (YouTube)), V-Detector (specifications (pdf)), R-Series Tunnel Detectors, and the T13 Tunnel Detector.
The Blue Wand has recently been discontinued, but you can find instructions for it here (how-to video (YouTube))
- The T-Wand is used for sampling in the field and where the volume of animals to sample is relatively low. It is portable, rugged and waterproof.
- V-Detectors are commonly used in labs for tag recovery from heads. They are also used at hatcheries or other sampling sites. They are not suitable for use on boats.
- R9500/R8000 Tunnel Detectors are used for detecting tags in large numbers of fish that must be sampled at hatcheries and processing plants. A gate can be added to the back of the detector to count and sort tagged and untagged fish. R-Series detectors can accommodate conveyor belts running through the tunnel. An optional Subsample Controller can be used to automatically subsample the tagged portion of a batch of fish.
- T13 Tunnel Detectors are used for detecting tags in large fish at hatcheries and can accommodate live adults. They are generally installed on site.