Survival of Upper Piedmont Stream Fishes Implanted with 8‐mm Passive Integrated Transponder Tags

Abstract

We studied weekly and bimonthly survival of select nongame fishes that were implanted with 8‐mm PIT tags in upper Piedmont streams of South Carolina, USA. Weekly survival in stream enclosures was assessed for a total of 350 tagged individuals and 311 control (untagged) fish (39–101 mm TL; median = 65 mm TL) belonging to six species (Bluehead Chub Nocomis leptocephalus, Creek Chub Semotilus atromaculatus, Yellowfin Shiner Notropis lutipinnis, Mottled Sculpin Cottus bairdii, Northern Hog Sucker Hypentelium nigricans, and Striped Jumprock Moxostoma rupiscartes). Weekly survival rates ranged from 93.3% to 100% among species, with Yellowfin Shiners experiencing the lowest survival rate. Only 2 of the 337 surviving tagged individuals lost their tags (0.6% tag loss). Logistic regression indicated that species and body length were statistically significant predictors of survival and tag retention. Odds ratios indicated that tagged fish were 1.718 times less likely to survive than control fish, but the tagging effect was not statistically significant. Bimonthly survival was estimated by conducting a mark–recapture study from September 2015 to May 2016, which involved tagging 1,413 unique individuals of Bluehead Chub (45–75 mm TL) in a 520‐m stream section and 431 individuals of Mottled Sculpin (45–75 mm) in another 740‐m section. Bayesian state–space analysis of Cormack–Jolly–Seber models indicated that apparent survival did not differ between newly tagged and previously tagged (i.e., recaptured) individuals in any sampling interval, suggesting that the acute and chronic effects of tagging did not differ. Mean bimonthly apparent survival rate was 0.76 (95% credible interval = 0.64–0.86) for Bluehead Chub and 0.74 (95% credible interval = 0.59–0.88) for Mottled Sculpin. Our results indicate that PIT tags can be successfully applied to study the ecology and life history of small‐bodied, nongame fish species, although caution should be exercised when selecting the species and body sizes to be tagged.

Detection Efficiency of a Portable PIT Antenna for Two Small‐Bodied Fishes in a Piedmont Stream

“…Lastly, we did not detect any tagged fish above or below the study reach with the portable PIT antenna despite the high detection efficiency of that antenna, at least for Mottled Sculpin. The mean capture probability of individuals with two-pass electrofishing in the study stream was 0.40 for Mottled Sculpin (Cary et al 2017) and 0.39 for Creek Chub (Y. Kanno, unpublished data) in comparison with 0.79 (12-mm tags) and 0.56 (8-mm tags) for Mottled Sculpin and 0.16 (12mm tags) and 0.03 (8-mm tags) for Creek Chub by using the single-pass portable PIT antenna. Along with high survival rates (>98%) of tagged fish over the 5-d study period (Cary et al 2017), it was highly likely that tagged fish were alive and stayed in the study reach, thus maintaining their availability for detection by the portable PIT antenna.…”

“…The mean capture probability of individuals with two-pass electrofishing in the study stream was 0.40 for Mottled Sculpin (Cary et al 2017) and 0.39 for Creek Chub (Y. Kanno, unpublished data) in comparison with 0.79 (12-mm tags) and 0.56 (8-mm tags) for Mottled Sculpin and 0.16 (12mm tags) and 0.03 (8-mm tags) for Creek Chub by using the single-pass portable PIT antenna. Along with high survival rates (>98%) of tagged fish over the 5-d study period (Cary et al 2017), it was highly likely that tagged fish were alive and stayed in the study reach, thus maintaining their availability for detection by the portable PIT antenna. However, if undocumented emigration of tagged fish from the study reach occurred, then our estimates of detection efficiency would be conservative, and true detection efficiency could be higher than the efficiencies reported here.…”

“…The 56% detection rate of Mottled Sculpin with 8mm PIT tags was higher than we had anticipated and was comparable to the capture probability of individual fish in single-pass backpack electrofishing, as reported for the Brook Trout Salvelinus fontinalis (57%; Letcher et al 2015), Mottled Sculpin (54%), Central Stoneroller Campostoma anomalum (54%), Creek Chub (55%), Brown Trout (59%), and Longnose Dace Rhinichthys cataractae (56%; Hense et al 2010). Use of 8-mm tags allows for the tagging of fish as small as 35-40 mm TL (Bangs et al 2013;Cary et al 2017;O'Donnell and Letcher 2017. Thus, the researcher is faced with a trade-off between higher detection efficiency but larger minimum fish size when using 12-mm tags versus lower detection efficiency but smaller minimum fish size when using 8-mm tags.…”

“…This method was utilized because of the Mottled Sculpin's soft ventral surface (Ruetz et al 2006). A pilot study using the same tagging methods indicated that survival and tag retention of Mottled Sculpin and Creek Chub (>40 mm TL) with 8-mm tags were greater than 98% over 1 week (Cary et al 2017). After handling, fish were allowed to recover in an aerated live well until normal swimming behavior was observed.…”

“…Data collected on uniquely marked individuals are useful for obtaining information on life history and biology (Ruetz et al 2006). Among marking techniques, PIT tags are commonly used in fisheries research because they are small in size and are relatively inexpensive Banish et al 2016;Cary et al 2017;O'Donnell and Letcher 2017). Passive integrated transponder technology has multiple applications in mark-redetection studies.…”