The Effect of PIT Tagging on Survival,Tag Retention,and Weight Gain in Fingerling White Bass

We tagged fingerling white bass, Morone chrysops, with passive integrated transponders (PIT) at two body locations (peritoneal cavity and dorsal musculature) and six weight classes to evaluate survival, tag retention, and weight gain during a 28-day experimental period. The probability of survival (as calculated by logistic regression) was >95% for fingerlings >19 g for both PC and DM. Retention of PIT tags varied between PC and DM tagged white bass in 6 g and 14 g fingerlings. The probability of tag retention was 100% in all sizes of fingerlings tagged PC, and >95% for fish >19 g tagged DM.     

A method for the attachment of miniature radio tags to small fish

Abstract An attachment technique which gives good tag retention, minimal damage to fish and prevents entanglement with weed is described. Fish carrying transmitters were monitored in semi-natural conditions and appeared to exhibit the same behaviour as untagged fish. Median condition factors of dummy-tagged fish did not differ from those of untagged fish over a 10-week period. Examples of movement patterns obtained using radio tags attached to dace, Leuciscus leuciscus (L.) are given.     

Do intracoelomic telemetry transmitters alter the post‐release behaviour of migratory fish?

Electronic tags have become a common tool in fish research, enhancing our understanding of how fish interact with their environment and move among different habitats, for estimating mortality and recording internal physiological states. An often‐untested assumption of electronic tagging studies is that tagged fish are representative of untagged conspecifics and thus show ‘normal’ behaviour (e.g. movement rates, swimming activity, feeding). Here, we use a unique data set for potamadromous walleye (Sander vitreus) in Lake Huron and Lake Erie tributaries to assess whether the lack of appropriate controls in electronic tagging could seriously affect behavioural data. We used fish tagged in previous years and compared their migratory behaviour during the spawning season to fish tagged in a current year at the same location. The objective of the study was to determine whether intracoelomic acoustic tag implantation altered downstream movement of walleye after spawning. Fish tagged in a given season travelled slower downstream from two river spawning sites than fish tagged in previous years. Fish tagged one or two years earlier showed no differences between each other in downstream travel time, in contrast to fish tagged in a given year. Our results support notions that standard collection and intracoelomic tagging procedures can alter short‐term behaviour (i.e. days, weeks, months), and as such, researchers should use caution when interpreting data collected over such time periods. Further, whenever possible, researchers should also explicitly evaluate post‐tagging effects on behaviour as part of their experimental objectives.     

Tagging: on the use of passive integrated transponder (PIT) tags for the identification of fish

To determine the efficacy of passive integrated transponder (PIT) tags for marking rohu Labeo rohita (Ham.) in the selective breeding programme, a series of experiments has been carried out at the Central Institute of Freshwater Aquaculture (CIFA) under the Indo–Norwegian project of ‘Selective breeding of rohu’. Six groups of rohu fingerlings with weight ranging from 2 g to 20 g were tagged with PIT tags to determine a suitable size range for tagging. Fingerlings weighing 8–15 g were found to be quite suitable for tagging with a PIT tag. Recovery of the PIT tag depends upon the survival of tagged fish under field conditions. Rejection of the PIT tag by rohu was observed to be only 0.05%. Through effective management practice, the survival of tagged fish increased up to 95%, and thus tag loss was minimized.     

Evaluation of a flat-plate PIT tag interrogation system at Bonneville Dam

In the spring of 1996 and 1997, a prototype 400 kHz flat-plate (pass-by) passive integrated transponder tag interrogation (PIT tag) system was installed at the terminus of the downstream migrant (DSM) channel of the Bonneville Dam First Powerhouse, located on the Columbia River. The system was designed to interrogate previously PIT tagged juvenile salmonids migrating down the Columbia River without interfering with the traditional subsampling of fish passing through the facility. In addition, the design enables fish of virtually any size, and debris, to pass over the system's antennas without the port restrictions imposed by traditional pass-through PIT tag interrogation systems. We describe the fish facility in addition to the flat-plate system and its operation. The system tag reading efficiency was evaluated during 1996 and 1997 using a direct method based on the release of known numbers of tagged test fish and an indirect statistical procedure based on tagged run-at-large fish. The results showed that PIT tag reading efficiency during both years using the direct method averaged 97%, while that using the statistical procedure averaged 99% for the dual multiplexed antenna array. During the 1996 and 1997 field seasons 4371 and 14 733 fish, respectively, were recorded. Daily system functionality was monitored using stick tests (i.e., the passing of PIT tagged sticks across the antenna array).     

乌江思林水电站库区鱼类增殖放流效果初步研究

为探究乌江思林水电站鱼类增殖放流效果,2013年和2014年对思林(沙沱)鱼类增殖放流站放流的中华倒刺鲃(Barbodes sinensis)和白甲鱼(Varicorhinus simus)部分个体进行了荧光标记,共标记放流1.98万尾中华倒刺鲃和4.56万尾白甲鱼,并在2014年与2015年进行了2个周期的回捕调查。结果显示,回捕调查捕获鱼类12种,共计2687尾;其中,中华倒刺鲃和白甲鱼的渔获物占比分别为1.60%和0.71%,未见荧光标记个体。通过走访调查,收集到标记中华倒刺鲃7尾(2014年6尾,2015年1尾)、白甲鱼7尾(2014年4尾,2015年3尾),回捕率分别为0.013%~0.049%和0.009%~0.030%,回捕地点共7个,距离放流地点226~24 105 m。研究表明,思林(沙沱)鱼类增殖放流站的增殖放流活动可对中华倒刺鲃、白甲鱼等起到一定增殖效果。为取得更好的增殖放流效果,建议调整放流方法、放流地点、加强渔政管理和宣传教育。     

The utility of visible implant (VI) tags for marking tropical river fish

In tropical fisheries where ageing fish is often difficult, tagging programmes offer an important means to estimate growth parameters and mortality rates. The majority of tags are large and attached externally via a puncture in the muscle. These characteristics may cause significant biological effects which bias parameter estimates. Visible implant (VI) tags offer a more benign means to individually mark fish. The utility of VI tags for marking five species of tropical river fish was examined. The results indicate that the tag and tagging operation had no influence on either growth or mortality, although tag retention was poor compared with other studies. For three of the five species, the only suitable tagging location was highly inconspicuous and therefore inappropriate for tagging programmes that rely upon fishermen to return tagged fish. Alternative tagging locations may improve retention rates and the visibility of the tag.     

Tracking bluefin tuna reproductive migration into the Mediterranean Sea with electronic pop‐up satellite archival tags using two tagging procedures

Thirteen adult bluefin tuna were tracked with electronic pop‐up satellite tags during their reproductive migration towards Mediterranean spawning grounds as they entered the Strait of Gibraltar. Fish were caught in tuna traps and tagged either underwater, with the aid of a modified spear gun, or on the deck of the boat. Fish tagged on board initially showed a shallower behavior than those tagged in the water. The pattern of horizontal movements was also different between both groups. Shortly after tagging, the eight fish tagged in the water entered the Mediterranean Sea. Six of these fish reached the spawning ground located southwest of the Balearic archipelago before heading back for the Atlantic, whereas the other two traveled farther east, reaching its easternmost longitudes between Formentera and Sardinia and the South Tyrrhenian Sea, respectively. In contrast, two out of the five fish tagged on board never entered the Mediterranean Sea, and another one did enter the Mediterranean when the reproductive season was already over. These results suggest an impact of the tagging procedure on the post‐release behavior of bluefin tuna. Excluding the tags that popped‐off east of the Strait of Gibraltar, bluefin tuna stayed in the Mediterranean Sea for 22–28 days. Analysis of the median depth indicated a shallow behavior during both day and nighttime throughout the return phase of the fish from the Mediterranean Sea to the Atlantic Ocean with the exception of the area around the Strait of Gibraltar, where they showed a deeper behavior that coincided with a marked vertical gradient in the currents.     

The source of autumn and spring downstream migrating juvenile Atlantic salmon in a small lowland river

Over 3 years, 32,444 age‐0 group Atlantic salmon (Salmo salar) parr tagged with passive integrated transponder tags throughout the River Frome catchment were assigned to one of three groups, nonmigrants, autumn migrants and spring smolts, depending on the detection and the timing of detection at downstream tag readers (situated 8.6 km above the tidal limit). We examined the effect of density at the time of tagging (n·m^?2), distance upstream from the tidal limit (km), fish length (mm), Fulton condition index, habitat type (divided into two types, main river and carrier), days after 1 September that each fish was tagged and year (replication) on the proportions of fish in each of the migration groups. Distance upstream from tidal limit was strongly negatively related to the proportion of autumn migrants and positively related to the proportion of spring smolts. Nonmigrants had a lower average body size than migrants, although there were no differences in the sizes of autumn migrants and spring smolts in September prior to migration. Fish density had no effect on migration strategy. A lower proportion of fish migrated as autumn migrants from the smaller carrier habitats than the main river channel. There is some evidence that those parr destined to become autumn migrants underwent a lower mortality rate during September before tagging than those destined to become spring migrants indicating possible physiological or behavioural differences between these two groups of fish at that time. More research into the factors responsible for initiating the autumn migration is required.     

Fish pass effectiveness for bullhead (Cottus gobio), perch (Perca fluviatilis) and roach (Rutilus rutilus) in a regulated lowland river

Abstract –  The effectiveness of a pool-and-weir fish pass in the regulated river Laarse Beek (Belgium) was assessed for bullhead ( Cottus gobio ), perch ( Perca fluviatilis ) and roach ( Rutilus rutilus ) from August 2002 to April 2003. Fish were caught by electrofishing downstream, within and upstream of the fish pass. They were marked with visible implant elastomer tags and released downstream of the fish pass. Our results suggest that the fish pass is ineffective for the bullhead because none of the 1270 tagged bullheads were recaptured in the upstream study area. Passage failure most likely resulted from excessive water velocities in the fish pass. On the contrary, 8% of the tagged perch and 29% of the tagged roach were recaptured in the upstream study area. Several management strategies are proposed to allow free upstream passage of the endangered bullhead at the fish pass under study.