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is that the subdermal or transparent tissue is too thin to hold the V. I. tag in fish smaller than 150 mm. The quantity of tissue in yearling Atlantic salmon (Salmo a ar) weighing less than 30 g was inadequate to hold and support the V. I. tag, and was associated with tag loss (Kincaid and Calkins 1992). Tag retention in yearling Atlantic salmon increased with fish weight. This tag might be useful for larger squawfish (e. g., >_ 150 mm) where adipose tissue is thicker to implant and retain the tag. Kincaid and Calkins (1992) reported V. I. tags were effective for Atlantic salmon larger than 30 g. Their study demonstrated that the percentage of readable tags was 100% among surviving yearling Atlantic salmon and 82% among surviving adult Atlantic salmon after 10 months. However, after 10 months, V. I. tag retention was only 49% for yearling Atlantic salmon; 84% for adult Atlantic salmon. Because the V. I, tag costs less than the PIT tag (e, g., current costs: V. I. tag=0.25 to $0.70/tag vs. PIT tag~E5.00/tag) this tagging system might be more practical-and suitable for projects with limited or restricted budgets. If this tag is to be used with larger squawfish, the performance of the tag should be tested to determine tag retention and biological tissue compatibility. Car i ©angler Taq. This tag was not tested on squawfish because fish were too small for the size of tag to be tested. Acr ]ic Dye. At day 195, verification of the red dye was only 24% for squawfish held in the raceway; only 15% for fish held in the pond (Appendix; Table 8); at day 343 and 511, both the primary dye marks and the secondary mark (lower caudal fin) were indistinguishable. The dye was applied externally and this may have been the reason for the poor mark retention. The application technique used was time consuming, requiring more than twice the time to complete com~arzd to the other tagging systems tested. Other studies successfully 16