Passive Integrated Transponder Tag Retention Research Articles

Retention of loop, monel, and passive integrated transponder tags by wild, free‐ranging Lake Sturgeon ( Acipenser fulvescens Rafinesque, 1817)

Tagging or marking of fish is instrumental to fisheries biologists and managers seeking to distinguish groups of fish, track movement or migration patterns, and monitor population characteristics. However, tag loss can inhibit the ability of biologists and managers to reach these objectives. The ability of Lake Sturgeon to live for long periods of time and reach large sizes, in combination with their dynamic spawning activity, requires tags to be retained under a variety of environmental and physically demanding conditions. This study evaluated tag retention of loop, monel, and passive integrated transponder (PIT) tags on wild, free‐ranging Lake Sturgeon in Lake Huron and the St. Clair – Detroit River System. Lake Sturgeon in this study were double‐tagged with both a PIT tag under one of the three anterior‐most dorsal scutes and an external tag (loop or monel) at the base of the dorsal fin. Fish were at large for up to 16 years. Overall, tag loss for PIT tags was 1% followed by monel tags at 12% and loop tags at 36%. Tag loss for loop tags was higher when the initial length of Lake Sturgeon tagged was smaller. Tag loss for monel tags increased with time at large but was not related to length at initial tagging. Monel tags left behind abrasion marks when attached to smaller Lake Sturgeon. PIT tag retention was higher than reported in previous studies that tagged other sturgeon species in different body locations. Monel tag retention was higher than other external tag types evaluated in previous studies while loop tags had similar retention rates to external tag types. Most previous studies on tag retention of sturgeon species were of shorter duration and conducted in laboratory settings, therefore loop tags may have performed more favorably during studies under short term laboratory settings. Results of this study suggest that PIT tags inserted below dorsal scutes represent a viable option for long‐term tracking of Lake Sturgeon. Monel tags attached at the base of the dorsal fin also seem to be a viable option relative to other external tag types, but should be limited to larger sturgeon as they can leave behind abrasion marks.

Ear tag and PIT tag retention by white‐tailed deer

ABSTRACTWhite‐tailed deer (Odocoileus virginianus) have been marked with various tags for a wide variety of applications, such as longitudinal, movement, disease, and mark–recapture studies. Tag persistence is critical to all these applications. We used nest survival models in Program MARK to estimate tag retention from 1) 832 free‐range white‐tailed deer marked with large plastic ear tags in both ears and Passive Integrated Transponder (PIT) tags in the leg and at the base of the ear, and 2) 412 free‐range deer marked with metal ear tags in both ears, captured in Texas, USA, 1997–2007. We calculated tag retention from 401 captive deer marked with 2 types of Electronic Identification (EID) ear tags (button or combi) in one ear and 36 captive deer marked with small plastic ear tags in one ear. Annual retention rates were greatest for button EID tags (0.992; 0.983–0.998), combi EID tags (0.979; 0.953–0.996), small plastic ear tags (0.978; 0.965–0.995), and large plastic ear tags (0.958; 0.950–0.965). Passive integrated transponder tags at the base of the ear (0.923; 0.910–0.935) and metal tags (0.909; 0.891–0.924) had fair retention rates. Passive integrated transponder tags placed in the leg (0.779; 0.758–0.800) had the lowest retention rate. Although many factors influence tag selection, EID tags and both small and large plastic tags demonstrate the greatest annual retention rates of both captive and free‐range, marked deer. © 2017 The Wildlife Society.

Passive Integrated Transponder Tags: Review of Studies on Warmwater Fishes With Notes on Additional Species

Abstract Although numerous studies have assessed retention and survival of passive integrated transponder (PIT) tags, data are scattered and information gaps remain for many diminutive fishes. Our study objectives were to 1) systematically review PIT tag studies and summarize retention, growth, and survival data for warmwater fishes; and 2) conduct a laboratory study to evaluate the retention, survival, and growth effects of intracoelomic-placed, half duplex PIT tags on six small-bodied species common to warmwater streams. Our systematic review suggested small sample sizes were common within PIT tag retention and survival studies (39% with n ≤ 20) and that many experiments (15%, 14 of 97) failed to use control fish as part of their evaluations. Studies focused primarily on short-term changes (15 d to 2 y) in tag retention and survival. Tag retention was equal to or greater than 90% in 85% of the experiments reviewed and median survival was 92%. Growth was reported by fishes in the majority of reviewed studies. We found similar results after PIT tagging (peritoneum tagging using 12- or 23-mm half duplex tags) adult Cardinal Shiner Luxilus cardinalis, Central Stoneroller Campostoma annomalum, Greenside Darter Etheostoma blennioides, Orangethroat Darter Etheostoma spectabile, Slender Madtom Noturus exilis, and juvenile Smallmouth Bass Micropterus dolomieu. Tag retention for all species was high, with only one tag loss recorded after 60 d. Survival was also high (≥88%) for all of our species with the exception of Orangethroat Darter (56% survival). No significant difference in mean growth between treatment and control groups was found. Both our results and the findings of the literature review suggested generally high tag retention and low mortality in tagged fishes (across 31 species reviewed). However, within our study (e.g., Orangethroat Darter) and from the literature, examples of negative effects of PIT tagging on fishes were apparent, suggesting methodological testing is prudent before using PIT tags in field studies. We suggest future studies would benefit from addressing the behavioral implications that may be associated with tagging and examination of longer-term tag retention. Furthermore, standard reporting (i.e., sample sizes) in PIT tag studies would be beneficial, and use of control subjects or groups for statistical comparisons is needed.

Short‐Term Passive Integrated Transponder Tag Retention in Wild Populations of Bluehead and Flannelmouth Suckers

AbstractPassive integrated transponder (PIT) tags, commonly used to individually identify fish, are assumed to not hinder survival or alter the behavior of the fish and to be retained throughout the duration of the study. While these assumptions have been verified for many species, other species have exhibited poor retention or survival, or altered behavior. In this study, we evaluated short‐term PIT tag retention and recapturability of PIT‐tagged fish in wild populations of migrating and spawning Bluehead Sucker Catostomus discobolus and Flannelmouth Sucker C. latipinnis. We trapped fish as they entered a spawning tributary of the Gunnison River near Delta, Colorado, USA. We abdominally injected 12.5 × 2.1 mm PIT tags and externally marked 2,645 fish; another 2,660 fish were given an alternative external mark but were not PIT‐tagged. When we recaptured fish as they exited the tributary, we found a PIT tag retention rate >99% and recaptured a greater proportion of PIT‐tagged fish than of control fish for both species. We did not identify any tag loss in females, suggesting that tags were not expelled with eggs while spawning. Abdominally injected PIT tags are an effective way of marking these species.Received November 22, 2016; accepted February 26, 2017 Published online April 18, 2017

Retention Rates of Passive Integrated Transponder Tags, Visible Implant Elastomer Tags, and Maxillary Marks in Wild Trout

AbstractTagging or marking is a common method to identify individuals or groups of fish, but these tools are compromised if tags or marks are shed or deteriorate over time. We evaluated retention rates of passive integrated transponder (PIT) tags, visible implant elastomer (VIE) tags, and maxillary clips in stream‐dwelling Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri and Rainbow Trout O. mykiss of spawning size. We tagged 2,891 fish ≥150 mm TL with PIT tags in the body cavity, muscle tissue posterior to the cleithrum, or muscle tissue ventral to the dorsal fin. Retention of PIT tags in the body cavity of fish at large for 1 year (72.1%) was lower than those implanted in the dorsal musculature (94.1%) or cleithrum (83.5%) locations. For PIT tags implanted in the body cavity, retention was lower for females (59.4%) than males (89.7%), suggesting that PIT tags implanted in the body cavity were expelled with eggs during spawning events. Retention of PIT tags implanted in the cleithrum and dorsal musculature were unaffected by sex, but retention rates decreased as body size increased for the body cavity tagging location. Annual growth rates were not affected by any PIT tag location. We observed a PIT tag failure rate of 1.7%. The likelihood of a PIT tag being retained in muscle tissue after filleting the fish was highest for the dorsal musculature location (65.1%), followed by the cleithrum (64.9%) and body cavity (4.0%) locations. One‐year retention rates were 95.4% for VIE tags and 93.0% for maxillary clips. While our results demonstrate higher PIT tag retention in the musculature than the body cavity, human consumption concerns may prohibit the use of musculature implantation where angler harvest is possible.Received January 28, 2016; accepted May 11, 2016 Published online August 31, 2016

Evaluation of passive integrated transponder tag retention from two tagging locations in juvenile pallid sturgeon

Summary Population augmentation and propagation of pallid sturgeon (Scaphirhynchus albus) have been a focus of scientists since the mid-1990s. Various tag types have been used to gain a better understanding of population characteristics, stocking success, and movement patterns. Passive integrated transponder (PIT) tags have been consistently used since the inception of recovery efforts to mark age-1 and older pallid sturgeon. This tag has been successfully used with other sturgeon species, and tagging protocols for pallid sturgeon were developed in response to those successes. Tag retention rates in pallid sturgeon have been reported as variable or unknown and there has been no formal study to determine PIT tag retention in pallid sturgeon, particularly with age-1 individuals that are propagated in hatcheries to be stocked into the wild. The objective was to evaluate retention rates of PIT tags inserted into the operculum and along the base of the dorsal fin of age-1 pallid sturgeon (total fork length [FL] range = 214–358 mm). Tagged sturgeon (n = 80) were held in a large holding tank and inspected for tag loss twice a month for a total of 189 days. Final tag retention was 83% for tags inserted into the operculum and 85% for tags inserted near the dorsal fin. Tags shed from the operculum were from smaller fish (mean FL = 265 mm) and losses occurred during the first 60 days of the experiment. Tags shed from the dorsal site were predominantly from larger individuals (mean FL = 305 mm) and losses were continual throughout the experiment. Future research should determine size-specific tag retention rates so that hatcheries can maximize retention in either tag placement location.

Tag Retention of T‐Bar Anchor Tags and Passive Integrated Transponder Tags in Shovelnose Sturgeon

AbstractCapture–recapture methods are commonly used to estimate population parameters when the necessary assumptions are met. One of the broadest assumptions of capture–recapture models is that tags are not lost. Therefore, one must understand tag retention to be able to adjust estimates if tag loss occurs. Our objectives were to (1) determine retention rates of T‐bar anchor tags and passive integrated transponder (PIT) tags injected into the dorsal musculature of shovelnose sturgeon Scaphirhynchus platorynchus and (2) determine whether using an alternative PIT‐tagging location (the operculum) and a new tagging procedure (cyanoacrylate [i.e., superglue] to seal the tag insertion point) provided higher retention. The T‐bar tags had a retention rate of 100%; PIT tag retention, however, was more variable. Injection of PIT tags along the dorsal fin resulted in a retention rate of 73%, and tag loss was observed throughout the 98‐d experiment. The application of cyanoacrylate did not appear to deter PIT tag loss; retention rates before and after cyanoacrylate was applied were 73% and 77%, respectively. Further, we observed a similar trend of continual PIT tag loss throughout the experiment. The operculum location resulted in a 92% PIT tag retention rate and showed no trend in cumulative loss through time. The high retention rate of PIT tags placed in the operculum suggests that this location is a reliable alternative to inserting PIT tags along the dorsal fin of adult Scaphirhynchus species. In addition, the excellent retention of T‐bar tags makes them a viable option for use in Scaphirhynchus studies.Received October 8, 2011; accepted March 1, 2012

Genetic markers reveal high PIT tag retention rates in giant salamanders (Cryptobranchus alleganiensis)

Estimation of population size using mark-recapture (MRR) methods are based on the fundamental assumption that individuals retain their marks throughout the course of study. Passive Integrated Transponder (PIT) tags are useful as a cost effective, reliable marking method in many amphibian and reptile species. Few studies however, use secondary methods to evaluate tag retention rates. Failure to do so can lead to biased population estimates, erroneous conclusions, and thus poor management decisions. Surprisingly, estimates of PIT tag retention are currently lacking for the majority of amphibian species, many of which are experiencing population declines. Herein, we use genetic tagging to assess the retention of PIT tags of the eastern hellbender (Cryptobranchus alleganiensis alleganiensis). We captured and tagged 78 individuals across 35 sites. Recapture rate was 24% and genetic tagging revealed 100% tag retention across all recaptured individuals.

Short‐ and Long‐Term Evaluation of Passive Integrated Transponder and Visible Implant Elastomer Tag Performance in Muskellunge

AbstractFisheries professionals charged with managing muskellunge Esox masquinongy frequently seek population information that requires the ability to identify cohorts as well as individuals; hence, reliable tagging methods are needed. Our approach was to simultaneously assess multiple marking techniques on different life stages of muskellunge over short and long time scales. We evaluated the short‐term detection of visible implant elastomer (VIE) and passive integrated transponder (PIT) tags in muskellunge fingerlings in experimental ponds. We compared survival (relative to that of control fish) and tag retention for two PIT tagging locations (the cheek and dorsal musculature) and one VIE location (the jaw). Overwinter survival did not differ between tagged and untagged fish (84–98%), but overwinter PIT tag retention was lower for the cheek (92%) than the dorsal musculature (100%). We also fin‐clipped and VIE‐tagged (jaw) 1,651 muskellunge fingerlings from 1997 to 2002 to evaluate long‐term tag retention in a broodstock lake. In addition, 125 adult muskellunge were captured and PIT‐tagged from 2003 to 2006. Muskellunge were sampled annually with trap nets and electrofishing during spring and fall. Only 2 VIE tags were detected in adults marked as fingerlings. The proportion of PIT‐tagged adults recaptured ranged from 52% to 84% during the sampling period. Our results indicate that both VIE and PIT tags are viable short‐term marks for muskellunge fingerlings, while PIT tags appear to be reliable long‐term tags when implanted in the dorsal musculature of adults.

Evaluation of VIE and PIT tagging methods for juvenile cyprinid fishes

Summary Retention and mortality associated with visible implant elastomer (VIE) and passive integrated transponder (PIT) tagged juvenile chub [Leuciscus cephalus (L.)], dace [Leuciscus leuciscus (L.)] and roach [Rutilus rutilus (L.)] were evaluated. PIT tag retention (96.6–100%) was higher than VIE over the 6-month duration of the experiment. VIE retention was significantly better in the head (96.3–98.8%) than in the fins (78.8–90.9%) the first month after tagging, but the opposite was found after 6 months (head = 21.5–57.5%; fins = 77.2–88.8%). Survival was not significantly different from controls for any treatment, except dace tagged with 23-mm PIT (significantly influenced by mass of fish at tagging) and sham PIT tagged dace, because of initial losses. PIT tags are recommended as the most suitable method for tagging individual juvenile chub, dace and roach based on high retention and survival. VIE implantation in the head (studies 30 days) could provide a cheap, batch-marking alternative, provided retention rates are monitored.

Passive Integrated Transponder Tag Retention Rates in Headwater Populations of Coastal Cutthroat Trout

AbstractPassive integrated transponder (PIT) tags have desirable qualities (e.g., unique identification, indefinite tag life, and capacity for remote detection) that make them useful for evaluating survival, growth, and movement of fish, but low tag retention rates can confound data interpretation. Although the effects of PIT tags on short‐term growth and survival have been minimal and tag retention rates in laboratory and field studies using only juvenile individuals have been high, tag retention rates for fish at different ontological stages (including reproductively active males and females) remain unknown. We evaluated tag retention rates in wild populations of coastal cutthroat trout Oncorhynchus clarkii clarkii in three catchments of western Oregon using a double‐marking approach (i.e., the adipose fin was removed from all fish that were PIT‐tagged). Tags were inserted into the body cavities of fish 100 mm or more in length (fork length; range = 100–250 mm). In the study catchments, this size range includes both juvenile and mature fish. Tag retention rates were approximately 25% lower than those reported by previous studies of juvenile salmonids alone. A number of PIT tags were recovered in redds, indicating that mature individuals eject tags during spawning. Although some coastal cutthroat trout retained PIT tags for up to 4 years, others expelled them repeatedly and were implanted with a minimum of three different PIT tags during the same period. These data are concordant with those of other studies in which PIT tags had been inserted into the body cavity of salmonids and the population of tagged fish comprised both juvenile and mature individuals. Therefore, for multiple‐year studies, it may be prudent to double‐mark fish when PIT tags are to be inserted in the body cavity.

Retention of Passive Integrated Transponder Tags in Flathead Catfish

AbstractWe evaluated short‐ and long‐term retention of passive integrated transponder (PIT) tags at two anatomical tagging locations in flathead catfish Pylodictis olivaris (n = 72 fish; total length range = 421–854 mm). Tags were injected into the dorsal musculature immediately posterior to the dorsal fin and into the opercular musculature immediately posterior to the left eye. Short‐term tag retention evaluated at 1, 3, and 7 d posttagging was 100% at both tagging locations after accounting for one tag failure (at the dorsal musculature site) that occurred during the initial tagging procedure. Long‐term (300‐d) tag retention was 100% for the dorsal musculature site and 98.5% for the opercular site. Mortality of tagged fish was low (8%); the mortalities that did occur were probably not related to tagging. Our results indicate a high rate of PIT tag retention in flathead catfish at both anatomical locations. Additionally, utilization of the opercular musculature as a PIT tagging location for this species may reduce the potential for accidental tag consumption by anglers.

Instream Evaluation of Passive Integrated Transponder Retention in Brook Trout and Brown Trout: Effects of Season, Anatomical Placement, and Fish Length

AbstractWe examined effects of tagging season, anatomical placement of tags, and fish total length (TL) at tagging on 2‐month retention of passive integrated transponder (PIT) tags in 181 brook trout Salvelinus fontinalis (99–302 mm TL) and 709 brown trout Salmo trutta (122–511 mm TL) in small streams of southeastern Minnesota. A lower percentage of brown trout retained their tags in spring (56%) than in fall (68%), but season did not affect tag retention in brook trout. Retention rates varied with anatomical placement for both species. For brook trout, retention was 70% when the PIT tag was placed into the body cavity using an insertion point that was posterior to the pelvic fins and 100% when the tag was placed into the dorsal musculature. Among brown trout, PIT tag retention was 56% for body cavity placement (posterior insertion) and 95% for dorsal musculature placement. Tag retention was not associated with fish TL for brown trout and was only weakly associated with TL of brook trout. Although reported retention rates of PIT tags implanted into the body cavity of salmonids have often exceeded 90%, our retention estimates were considerably lower. This discrepancy can be partially attributed to differences in laboratory versus field studies. However, most previous studies of salmonids have used body cavity insertion points that were anterior to the pelvic fins, whereas we used a posterior insertion point; this was probably the primary factor responsible for the difference in results. We caution against the assumption that retention of PIT tags is universally high, and we recommend the estimation of PIT tag retention before or during marking studies. We also provide a list of factors that should be considered and evaluated when designing PIT tag studies, especially tag retention studies.

Evaluation of passive integrated transponder tags for marking the bullhead (Cottus gobio), a small benthic freshwater fish: effects on survival, growth and swimming capacity

Abstract – This study examined potential adverse effects of surgically implanted passive integrated transponder (PIT) tags (12 × 2.1 mm) on bullhead (Cottus gobio L.) of three different length‐classes (I: 50–64 mm, II: 65–79 mm, III: 80–94 mm). During a 7‐week laboratory experiment, the rate of PIT tag loss, incision closure time, survival, growth and swimming capacity were tested. The PIT tag weight to fish body weight ratio varied between 1.04% and 4.85%. The mean incision closure time differed significantly among length‐classes and varied between 2.8 (I) and 4.3 (III) weeks. Nevertheless, PIT tag retention did not differ among length‐classes and was ≥90%. The survival of untagged, sham‐tagged and PIT‐tagged bullheads was ≥90% and did not differ within or among length‐classes. Finally, within each length‐class, there was no difference in growth and swimming capacity among treatments. Hence, these results suggest the applicability of PIT tags for individually tagging bullheads ≥50 mm.

Retention of T-Bar Anchor Tags and Passive Integrated Transponder Tags by Gulf Sturgeons

One thousand nine-hundred and four Gulf sturgeons Acipenser oxyrinchus desotoi were marked and returned to the Suwannee River, Florida, between March 1988 and November 1993 as part of life history and population dynamics studies, This Atlantic sturgeon A. oxyrinchus subspecies is federally listed as threatened, A T-bar anchor tag was placed into both pectoral fins, and a passive integrated transponder (PIT) tag was injected near the base of the dorsal fin of each fish to enhance the expected recovery rate and to provide a means of estimating tag retention. Relative tag retention was estimated from the ratio of recaptured fish with a specific tag to the total number of tagged fish recaptured. Relative tag retention was 89.3–94.9% for both types of tags during the first year at large. However, during the latter years of the study, retention for anchor tags declined in most cases to about 60%, while PIT tag retention remained near 90% throughout the evaluation. Both tags were retained at levels useful for many types of tagging studies, For sturgeon studies that are intended to last only a few years, anchor tags attached to the pectoral fins may be the most economical choice, Following a low initial rate of loss, PIT tags are probably retained for the life of the fish and thus are recommended for long-term studies.