MFR PAPER 1069 Coded wire tagging is excellent for automatic identification. Marking Fishes and Invertebrates. III. Coded Wire Tags Useful in Figure 1 ~Magnlf1ed binary and color coded wire tags (actual size 1 X 0.25 mm) . Automatic Recovery of Chinook Salmon and Steel head Trout t~ not without fault. Problem with tag 10 . malfunction of the tagging WESLEY J. EBEL gear. and later detecti n of the tag o n adult fi hare ome of them . but recent ren nement of the InJector. ABSTRACT detectors, and mark and recover} method In the fie ld ha\. e eliminated The SII( (1'I.lflll Ille of Ihe coded wire IllR (/ X 0.25 /11111. pillced III 111(1(/1) mo t of the problem. I nllial co t of for IIlllrkillR ofJII\'e llile Pacijic .\(/1/11011 (Oncorh) nchulpp ) £llld Ileelhe(ld lrolll equipme nt I relativel) high. however. (Salmo galrdnen) lIlil{rllfillR dOli mlre£l/ll III Ihe SlIlIke RII er II del( rthed ""hlch can be a dl advantage. Prohlelll.1 lI.I\Ocialed w/lh lal?l?/lIg lIlId wilh dele( /101/ of IlIl?1 III (/(/1111 jilh At pre ent t"" o t) pe of commer­ pre\'iollsl\, lIlarked £IS I/IIOIIS (Ire di.l( Il.I\I!d Geller£ll delcnp/lo//.I oj Ihe lIlI{(/ll/(lIic c iall y available tag InJe to r and two /(II{ delecfOr and adllil fish sep£lrlllOr (Ire gil ell t)pe of wire (blnar) and color coded. ig . I) are a\ailable. Detecllon y­ tem f r recovery al 0 are avai lable INTRODUCTION Ebel. Park. and J o hnsen ( 1973). Their from two commercial firm. data indicated that cold branding has We recognized the potential of the The problem of marking or tagging considerable potential a aver atile magnetized wire tag for automatic Juvenile salmon and trout for later form of marking certaIn pecies and detection and eparation of tagged identification as adult has perplexed ize range. However. the ptimum adult almon. y tem. or de ice. fishery bIOlogist for year. The mo t technique for u e on a given pecie that would detect and eparate tagged common method has been to excise and size ra nge till in the proces from untagged fi h wa needed in one or more fins. This procedure often of evaluation. evaluating our experiments on tran - results in problems of excessive tress A promising method for lo ng-term ponation of juvenile fi h past hazardous and disease-or sometimes in changed mark appear to be the coded wire areas. We developed an automatic behavior and growth (Bergman et al.. identification system develo ped by y tem with the a i tance of Dr. Keith 1968). Moreover. fin-clipping of exper­ Jefferts. Bergman. and Fi cu (1963). J effert and other per onnel of the Imental groups of fish does not allow It was further evaluated by Bergma n Technical Re earch Company. eattle. more th an two comparably marked et al. ( 1968) and by H ager and Jewell Washington.1 Thi sytem wa ucce - groups. Experiments that require com­ ( 1968). M any of the disadvantage fully operated in fish ladder on the parison among several experimental associated with fin-clipping are elimi­ Snake River at Ice H arbor and Little groups cannot be conducted without nated. and an almo t unlimited num­ Goose Dam from 1970 to the present. bias as one or more of the experiment­ ber ( 10(;) of experimental group can Ice Harbor is in Wa hington State al groups will have additional or be identified . This system. of course. near the conAuence of the Snake and different fins removed. Columbia Ri vers; Lillie Goo e The use of thermal marks (hot and approximately 65 miles up tream . cold) on juvenile Pacific salmon. On­ corhynchus spp., and steelhead trout, Wesley J. Ebel is a member of the staff of the Northwest Fish­ S(i/111 0 gairdneri , for later identifica­ eries Center, National Marine tion as adults has been descri bed by I Reference 10 trade names does not Imply Fisheries Service, NOAA, endorsement by the National Marone Flsheroes Groves and J one (1969) and by Seattle, WA 98112. Service. NOAA. 10 Figure 2.-Cross section of juvenile chinook salmon showing placement of coded wire lag. CODED WIRE TAG USED IN MARKING NATURALLY MIGRATING JUVENILE SALMONIDS Use of the wire tag for marking salmonids was formerl y limited to hatchery stock. To evalu ate our ex­ periments on the Snake River, it was necessary to mark naturally migrating hatchery or wild juveni Ie spri ng and summer chinook salmon, O. Ishawyl­ scha, and steel head trout. We soon found that marking of these stocks of primarily wi ld fis h with wire tags presented unusual problems. Juvenile almon and steel head migrating in the lower Snake River consist of many race . Consequently there is wide diversity in size range of the migrants, depending on the time that one wishes initial tag los was 9.2, 5.0, and I to sample the population. Our project percent. Tag loss from fish now being was ambitious. We wished to mark marked at Little Goose Dam has been samples from all stocks' or race . For less than I percent. a successful taggi ng operation, correct Overall tag loss (from time of tag­ placement of the tag was highly criti­ ging to return of adults) was obtainable cal. Bergman et al. (1968) found that from those marked in 1968 when 9.2 Tog guide ports the best area for inserting the tag was percent initial tag loss was recorded. the cartilaginous wedge of the chon­ Overall tag loss was 27 percent from drocrani um located in the snout an­ that year's marking. We attributed this terior to the eyes (Fig. 2). high tag loss primarily to poor place­ Since we were attempting to mark ment of the tag because of inexperi­ two species of fish with a wide range enced taggers. Lack of refinement of of sizes, it was necessary to construct the earlier tag injectors and head a facility where fish could be con­ molds also contri buted to this tag veniently sorted by size and species 10 s. Overall tag loss was not obtain­ and routed to an injector with a head able in 1969-70 because of lack of suffici ent return. At Little Goose, Figure 3.-Opan (top) end clo.eeI-type (bottom) mold of appropriate size for accurate head molds used in positioning head of fish placement of the tag (Fig. 3). recent overall tag loss was 3 percent. for wire lagging. Both mobile and stationary facilities (Fig. 4) were constructed where large sam pl es of juvenile fish could be held, anestheti zed, and sorted. The e facil­ ities have worked well. Tagging tech­ niques have been refined to the point where initial tag loss (determined by checking several days after tagging) i less than I percent. In 3 successive years of tagging from 1968 to 1970, Figure 4.-lnside of marking building showing sorting area and tagging localions. 11 Gro' lnQ '0 cover orl'lce Detector he ad Diversion gote open I I II C7 It:; r::; 1:: 1 0 ~ ::0.... I~ Air supply Pumps ~etector -d c c::! c i\.j:! II If ~ ~ 1 Gate closed \ False weir Detector head o Figure 5.-Plan views and Isometric diagrams of wire lag detector and fish sepa rator systems used at Ice Har bor Dam ( upper) and Little Goose Dam (lower). 12 Thus, we concl ude that coded wire tor proved satisfactory. however. when separati o n of over 1.500 tagged fis h tagging is a n excell ent method of taken out of the water and u ed in a fr o m the mi grati o ns passi ng up the marking naturally migrating as well fish ladder where fish jumped over a ladder at Little Goo e Da m . A lthough as hatchery stocks of Pacific salm on fa lse weir and slid down a chute past d ata o n exact efficie ncy of the unit and steel head trout. the detector. This movement was are in complete at this time, a pre­ rapid enough to induce suffici ent liminary estimate indicates that at current for detection . least 70 percent of all tagged fis h ADULTS DETECTED AND A prototype sys tem was built a nd passing up the ladder were success­ SEPARATED AUTOMATICALLY installed at Ice Harbor Dam in 1970 full y detected and separa ted . (Fig. 5) fo r use in detecting a nd The unit was also used to assi st As indicated earlier, our primary examining adult fi h, tagged as ju­ other orga ni zati o ns in their in vesti ga­ interest in using the coded wire tag veniles in 1968. This system was ti o ns. F or example. data from over was because of it potential fo r auto­ successful in automatic detection and 1, 000 adult salm o n carrying magne­ matic detection and recovery o f natur­ separatio n of about 300 tagged adult ti zed spaghetti tags were reco vered all y migrating adult chinook and spring and summer chinook from a and relayed to the F i h C ommiSSio n steelhead ascendi ng fish ladders. Such run of about 30,000 fish that passed o f Oregon. a sy tem was needed to evaluate the through the unit. results of experiments in which we The need fo r severa l impro ve ments CONCLUSION tran ported juvenile fish past barri er was indicated .