Long‐Term PIT and T‐Bar Anchor Tag Retention Rates in Adult Muskellunge

Abstract

Mark–recapture studies require knowledge of tag retention rates specific to the tag types, fish species and size, and study duration. We determined the probability of tag loss for passive integrated transponder (PIT) tags implanted into dorsal musculature, T‐bar anchor tags attached to dorsal pterygiophores, and both tags in relation to years posttagging for double‐marked adult muskellunge Esox masquinongy over a 10‐year period. We also used PIT tags as a benchmark to assess the interactive effects of fish length at tagging, sex, and years posttagging on T‐bar anchor tag loss rates. Only five instances of PIT tag loss were identified; the calculated probability of a fish's losing its PIT tag was consistently less than 1.0% for up to 10 years posttagging. The probability of T‐bar anchor tag loss by muskellunge was related to both the number of years posttagging and the total length (TL) of the fish at tagging. The T‐bar anchor tag loss rate 1 year after tagging was 6.5%. Individuals of less than 750 mm TL at tagging had anchor tag loss rates less than 10% for up to 6 years after tagging. However, the proportion of fish losing T‐bar anchor tags steadily increased with increasing years posttagging (∼30% after 6 years) for larger muskellunge. Fish gender did not influence the probability of T‐bar anchor tag loss. Our results indicate that T‐bar anchor tags are best suited for short‐term applications (≤1 year) involving adult muskellunge. We recommend use of PIT tags for longer‐term tagging studies, particularly for muskellunge larger than 750 mm TL. Received November 19, 2010; accepted March 28, 2011

Identification of stocked muskellunge and potential for distinguishing hatchery‐origin and wild fish using pelvic fin ray microchemistry

“…However, it is often difficult to distinguish between wild and hatcheryreared fish and thus difficult to determine the contribution of current stocking practices to fish populations. T-bar anchor and passive integrated transponder [PIT]; Younk et al 2010;Rude et al 2011), and fluorescent marks in hardpart structures (e.g. fin clips and freeze branding; McNeil & Crossman 1979;Johnson & Margenau 1993;Conover & Sheehan 1999), external and internal tagging (e.g.…”

“…oxytetracycline; OTC, and calcein; Brooks et al 1994;Conover & Sheehan 1999;Farrell & Werner 1999;Mohler 2003). External and internal tags are a promising technique because they typically have high retention rates (>90% for PIT tags; Younk et al 2010;Rude et al 2011;and >70% in ≤ 2 years for T-bar anchor tags ;Clugston 1996;Buzby & Deegan 1999;Rude et al 2011) and offer the ability to distinguish specific cohorts along with individual fish (Guy et al 1996). However, clipped fins and freeze brands may regenerate, resulting in loss of the mark or a decreased confidence in identification (McNeil & Crossman 1979), and anglers tend to view missing or mutilated fins or burn marks as undesirable (Nielson 1992).…”

“…However, clipped fins and freeze brands may regenerate, resulting in loss of the mark or a decreased confidence in identification (McNeil & Crossman 1979), and anglers tend to view missing or mutilated fins or burn marks as undesirable (Nielson 1992). Tagging advanced fingerlings is often a viable marking technique (PIT: Wagner et al 2007;Younk et al 2010;Rude et al 2011), but it may not be cost-effective to tag an entire batch of individuals due to a high cost per tag and post-stocking mortality (Johnson & Margenau 1993). However, tagging fry and small fingerlings is challenging because tag size is often too large (Sutton & Benson 2003).…”

Retention of PIT and T‐Bar Anchor Tags in Blue Catfish

“…These tags are small, about 12 mm long × 2 mm in diameter (Guy et al 1996), *Corresponding author: kris.bodine@tpwd.texas.gov Received July 29, 2013accepted October 15, 2013 and produce little or no effect on biological performance (Jenkins and Smith 1990;Prentice et al 1990). T-bar anchor tags are one of the more commonly used external tags, primarily due to their low cost (about US$0.30 to $0.70 each in 2013; Floy Tag and Manufacturing, Inc., Seattle, Washington), ease of application, and ability to display more information than alternative tags (Guy et al 1996;Rude et al 2011). Unfortunately, retention rates can sometimes be low (≤75% annual retention, Greenland and Bryan 1974;Buckmeier and Irwin 2000), and like PIT tags, retention can vary by species, necessitating species specific evaluations.…”

Comparing tagging strategies: Effects of tags on retention rate, mortality rate and growth in hatchery-reared juvenile meagre, <em>Argyrosomus regius</em> (Pisces: Sciaenidae)

“…However, one constraint of these studies is the loss of both tags, so a "permanent tag" such as PIT, CWT or VIE has been used for comparison (Brennan et al 2005, Josephson et al 2008, Rude et al 2011. In this study, the experiment conducted with the T-bar anchor tag, internal anchor tag and VIE had two goals: to seek an alternative to T-bar anchor tag (in the case of the internal anchor tag), and to select a "permanent tag" for future experiments under natural conditions (in the case of VIE).…”