Reference | Hale, R. S. and J. H. Gray. 1998. Retention and detection of Coded Wire Tags and elastomer tags in trout. North American Journal of Fisheries Management 18:197-201. |
Abstract | Tag retention rates above 95% and easy tag detection were possible with blank Coded Wire Tags and elastomer tags implanted in a variety of body locations of adult trout (Salmo and Oncorhynchus spp.). These tags were used in a generic way to differentiate 6 groups of brown trout Salmo trutta (142-254 mm total length, TL) and 26 groups of rainbow trout Oncorhynchus mykiss (80-314 mm TL) that were stocked at different times and locations in the Cumberland River, Kentucky. Retention rates (19-30 d) ranged from 92% to 100% for Coded Wire Tags implanted in the snout, left cheek, and muscle near the left pectoral, pelvic, dorsal, adipose, and caudal fins. Retention rates (24-30 d) ranged from 94% to 99% for elastomer tags placed in the left and right adipose eyelids and the caudal fin rays. Loss of Coded Wire Tags by trout did not increase with the number of days tagged fish were held in raceways, which suggested that most tag loss had occurred before stocking. By contrast, loss of elastomer tags increased with holding time and may have continued after stocking; therefore, we recommend further investigation of elastomer tag retention. Two inexperienced creel clerks successfully detected the body locations of Coded Wire Tags 91% and 98% of the time following only 1 h of training. Detection of the presence or absence of Coded Wire Tags was easy and precise; however, accurate determination of tag location could become a source of error if adjacent tags are too close together as a result of the selection of tag location or fish size. Visual detection of elastomer tags was enhanced by a black light, but detection was obvious and required minimal training. |
Tag | Coded Wire Tag (CWT) Visible Implant Elastomer (VIE) |
Objective | Evaluate tags |