This product is sold by BIOWEB in America countries butif you are in United States or Canada. Please contact the vendor Northwest Marine Technology directly.
The VI Alpha Tags are a small, fluorescent tags with an alphanumeric code designed to identify individual animals. VI Alpha Tags are implanted internally but remain externally visible for easy recovery. The new VI Alpha Tags were introduced in 2010.
VI Alpha Tags are available in two sizes: standard (1.2 mm x 2.7 mm), shown in yellow, and large (2 mm x 5 mm), shown in orange. The larger tags are easier to read than the standard tags, and are suitable for larger animals.
Large tags have black lettering on a fluorescent orange background, while standard tags are available with black lettering on a fluorescent orange, red, yellow or green background. Each color has 2,500 different codes. The codes available are the letter-number-number combinations from A00 through Z99 (excluding Q00-Q99).
Tag readability and detection can be enhanced by fluorescing the tags with the VI Light.
VI Alpha Tags are easy to load. Slide the tag into the needle, and snap it off.
Each 100 tags ordered must be the same color, and will have consecutive coding.
Please contact us for advice about applications to particular species.
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) 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). 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%. More on Adipose Eyelid Tissue here.
VI Alpha and VI Elastomer 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.
VI Alpha Tags are not as widely used as VIE, but there are also many publications available that describe their use. In thick skinned, or heavily pigmented species, the numbers may not be visible, so it is important to consider the species to be tagged and the location of the tag. For example, Clemas et al. (2009) found that the pigmentation of Litoria raniformis obscured the tags, but VI Alpha were reliable for tagging large Litoria ewingii. On the other hand, Heard et al. (2008) was able to tag juvenile Litoria raniformis with VI Alpha tags and found they remained readable. As with VIE tags, using the VI Light dramatically improves the detection and readability of VI Alpha tags, sometimes even through highly pigmented skin.
Measey et al. (2001) found there to be no negative effects of VI Alpha tags in a legless amphibian (Gegeneophis ramaswamii), and further stated that when individual identification is necessary that these tags are the “most promising” of the investigated tags. Buchan et al. (2005) tested VI Alpha in a number of species, and concluded that VI Alpha “appears to be an effective and low cost method for individually marking and identifying amphibians”. Kaiser et al. (2009) evaluated and used VI Alpha Tags to track individual Dendropsophus microcephalus.
Osbourne et al (2011) discuss the use of VI Alpha tags in juvenile ambystomid salamanders and provide extensive detail about their application and readability.