VISIBLE IMPLANT ALPHA TAGS (VIA)

The VI Alpha Tag is a small fluorescent tag with an alphanumeric code designed to identify individual animals. VI Alpha Tags are implanted internally but remain externally visible for easy recovery.

Our VI Alpha Tags are:

• Easy to load and inject;
• Less expensive than the Soft VI Alpha Tags;
• Stable for long-term storage; and
• Backed by our one year guarantee and expert customer service.

The VI Alpha Tags are available in one size (1.2 mm x 2.7 mm) with black letters on a fluorescent red, orange, yellow, or green background. Each color has 2,500 different alphanumeric codes. The visibility of the fluorescent colors and tag readability is enhanced with NMT's VI Light.   

VI Alpha Tags in ambient light (left) and illuminated by the VI Light (right).

During testing, the retention and readability of the VI Alpha Tags was at least as high as the Soft VI Alpha Tags, and all testers commented positively about the ease of using the new tags.

NMT's new VI Alpha Tags are easy to load. Slide the tag into the needle, and snap it off.

NMT's VI Alpha Tags are easy to load. Slide the tag into the needle, and snap it off.

Along with the tags, we redesigned the VI Alpha Tag Injector. The new needle is much sharper and can be inexpensively replaced. Existing injectors can be retrofitted with the new needle to accommodate the new tags. Most reptiles and amphibians can now be tagged directly with the injector, rather than having to make an initial cut in the skin to insert the injector.    

For more information, or to place an order for the VI Alpha Tags  (for a limited time, custom orders of the soft VI Alpha Tags will be available for continuing projects.) please contact NMT Biology (biology@nmt.us; 360-596-9400) for availability and pricing.

Using VI Alpha Tags  

VI Alpha Tags are easiest to read when they are placed under clear or translucent tissue. In some cases, the tags can be placed under pigmented tissue where they are not visible in ambient light, but can be seen when they are fluoresced with the VI Light. This tends to be more effective if the tissue is evenly pigmented rather than mottled.  

Many fish have transparent tissue (adipose eyelids, fin membranes, clear boney tissue, etc.), but tag retention varies by body location and species. For example, the adipose eyelids of salmonids have generally proven to be suitable for VI Alpha tags, but implants into similar tissue in mullet (Mugulidae) have been rapidly shed.. Buckmeier and Irwin (2000) [Abstract] found that 100% of VI Alpha Tags implanted in the dorsal fin of channel catfish Ictalurus punctatus were shed. However, researchers with the Iowa Department of Natural Resources developed a successful method of implanting VI Alpha tags into the tongue of flathead catfish (Pylodictis olivaris). Please see our Spring 2000 newsletter(PDF 45K) for further details. The size of the tagged animal is also important. Shedding rates from adipose eyelids of salmonids less than 150 mm total length can be excessive while retention in larger fish often exceeds 90%.

VI Alpha Tags are widely used for individual identification of amphibians as an alternative to toe clipping. Tag retention tends to be nearly 100%, although the visibility of the tags varies based on the pigmentation of the overlying skin.

 

NMT INC Northwest Marine Technology | PO Box 427, Ben Nevis Loop Rd Shaw Island, WA 98286, USA | (360) 468 - 3375 | office@nmt.us