Marks In Otoliths Research Articles

Age and Growth of Canadian East Coast Pollock: Comparison of Results from Otolith Examination and Mark–Recapture Studies

Abstract Pollock Pollachius virens were marked and released at relatively young ages in Canadian Maritime waters during 1979–1984. Substantial (n = 694) recaptures provided a unique opportunity for validation of age determinations made from examination of otoliths. Comparisons of mean lengths at age (age as determined from otolith examination) and the lengths at the assumed age (age at release, plus years at liberty) of recaptured fish indicated no significant differences. However, some (n = 211) of the recaptured tagged fish were also returned with the corresponding otoliths for each individual, and age determinations were completed. Thus, individual comparisons of otolith-derived ages and assumed ages were possible for those fish. Such comparisons revealed a tendency for the ages derived from otolith examination to exceed the assumed age by a year. Though these findings indicate a potential bias in age determinations during the 1980s, results from stock assessments indicate that strong and weak cohorts ...

Survival and Straying of Auke Creek, Alaska, Pink Salmon Marked with Coded Wire Tags and Thermally Induced Otolith Marks

Abstract Pink salmon Oncorhynchus gorbuscha fry from Auke Creek, Alaska, were marked with coded wire tags (CWTs) and, in some cases, thermally induced otolith marks, to investigate the effects of the CWT process on survival and straying. Pink salmon from Gastineau Hatchery that had been thermally marked provided a point of comparison. Marked fish were also used to estimate the natal composition of fish in nearby streams and at Auke Creek and Gastineau Hatchery. The survival of fish with both CWTs and thermal marks was significantly lower than that of fish with thermal marks alone but not significantly different from that of fish with CWTs alone. No effect of CWTs on straying was detected. The estimated straying rates were 4.4% and 6.7% for early-run and late-run Auke Creek fish, respectively, and 6.9% for Gastineau Hatchery fish. The observed straying and run composition estimates indicated a large-scale interchange of adult pink salmon among local streams, which may promote rapid colonization and recover...

Age, growth, and commercial landings of yellowtail scad (Trachurus novaezelandiae) and blue mackerel (Scomber australasicus) off the coast of New South Wales, Australia

Size and age compositions of yellowtail scad (Trachurus novaezelandiae Richardson 1843) and blue mackerel (Scomber australasicus Cuvier 1832) were studied in the inshore purse‐seine fishery off the coast of New South Wales, Australia. Ages were assigned by counting annual marks in otoliths for both species. Sampling from two regions showed no geographical differences in the age compositions of catches for either species. The fishery for yellowtail scad was based on 2‐ and 3‐year‐old fish, but with significant numbers of fish up to 11 years. Seventy percent of the fishery for blue mackerel was based on fish aged 1 year, with the majority of the rest being in their first or third years. Maximum ages recorded in this study were 14 years for yellowtail scad and 7 years for blue mackerel. We found no major differences in the sizes of blue mackerel landed in either region sampled, but yellowtail scad were larger in the northern region than in the southern. Growth rates of blue mackerel were the same from both regions, but yellowtail scad sampled grew significantly faster in the northern region. The fishery for yellowtail scad off New South Wales is currently based on younger and smaller fish than other trachurid fisheries around the world. This, together with the observed spatial variation in growth and population structure, suggests that the fishery for yellowtail scad in New South Wales should be carefully monitored.

The use of alizarin complexone for immersion marking of otoliths of larvae of gilthead sea bream, Sparus aurata L.

Fisheries Management and EcologyVolume 8, Issue 3 p. 279-281 The use of alizarin complexone for immersion marking of otoliths of larvae of gilthead sea bream, Sparus aurata L. A. Sánchez-Lamadrid, A. Sánchez-Lamadrid Centro de Investigación y Cultivo de Especies Marinas ‘El Toruño’, El Puerto de Santa María, Cádiz, SpainSearch for more papers by this author A. Sánchez-Lamadrid, A. Sánchez-Lamadrid Centro de Investigación y Cultivo de Especies Marinas ‘El Toruño’, El Puerto de Santa María, Cádiz, SpainSearch for more papers by this author First published: 20 December 2001 https://doi.org/10.1046/j.1365-2400.2001.00248.xCitations: 11 A. Sánchez-Lamadrid, Centro de Investigación y Cultivo de Especies Marinas ‘El Toruño’, Apdo, 16, 11500 El Puerto de Santa María, Cádiz, Spain (e-mail: alfonso.rey@teleline.es) Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume8, Issue3June 2001Pages 279-281 RelatedInformation

Validation of otolith growth-increment periodicity in tropical gobies

We assessed the efficacy of tetracycline, calcein and strontium chloride for validating the periodicity of otolith growth-increments in eight species of tropical marine gobies (family Gobiidae). We compared the number of fishes in which the otoliths were successfully marked when each of these chemicals was administered by intraperitoneal injection or immersion bath at a range of doses and immersion times. All three chemicals could produce a detectable mark in the otoliths of five reef-flat gobies, Asterropteryx semipunctatus, Amblygobius bynoensis, Istigobius goldmanni, Valenciennea muralis and Amblygobius phalaena; however, tetracycline injection at 50 mg kg−1 is recommended because it produced a brighter otolith mark than calcein and is cheaper and quicker to detect than strontium chloride. Calcein immersion treatment of 125 mg l−1 for 24 h was the most successful treatment for two estuarine gobiids, Favonigobius reichei and Glossogobius biocellatus. No treatment produced a detectable mark in the otoliths of the coral-dwelling goby Gobiodon histrio. Adequate care in the preparation of otoliths was found to be essential for detection of the validation mark produced by tetracycline and calcein. Otolith growth-increments were deposited daily in the seven species of goby for which validation was possible.

Age, Growth, and Sexual Development in the Self-fertilizing Hermaphroditic Fish Rivulus marmoratus

We studied age, growth, and sexual development in the early life intervals of the self-fertilizing mangrove killi-fish, Rivulus marmoratus. Newly hatched (day 0) individuals had sagittal otoliths of 60 μm radius, with about 30 increments. Sequential sampling until about day 60 after hatching yielded otoliths with the number of increments outside the 60 μm radius equal to the daily age of the fish. Alizarin complexone marking of otoliths also confirmed the increments were daily, and demonstrated the applicability of this technique to field studies for capture-mark-recapture, or age and growth estimates. Individuals fed a restricted amount of food formed fewer daily otolith growth increments than fish fed to satiation each day. Using histological analysis for identifying gonad morphogenesis, we found no correlation between gonadal development and external appearance (caudal ocellus, orange fin colouration) in young fish of known ages. The caudal ocellus was not present until 9 mm total length, and developed thereafter. Of 136 individuals examined, fish less than 17.2 mm total length (TL, n = 124) were females. Testicular tissue first appeared among individuals 17–18 mm TL (n = 3), while some individuals greater than 18 mm TL (n = 8) were functional hermaphrodites. The single male in our study was relatively of small body size (9.6 mm, day 37) with a distinct caudal ocellus, indicating that it is presumably a primary male.

Origin of juvenile Pacific salmon recovered from coastal southeastern Alaska identified by otolith thermal marks and coded wire tags

First ocean-year juvenile Pacific salmon ( Oncorhynchus spp.) in the marine waters of southeastern Alaska were examined for origin identification in the summers of 1993–1997. Over 31,000 juvenile pink ( O. gorbuscha), chum ( O. keta), sockeye ( O. nerka), coho ( O. kisutch), and chinook ( O. tshawytscha) salmon were scanned electronically for coded wire tags (cwt’s). Cwt’s were decoded to indicate tagging origins and release sites. Few (49) fish examined contained cwt’s. A sub-sample of the scanned juvenile pink (1,698), chum (1,685), and sockeye (189) salmon were also examined for thermally induced otolith marks (thermal marks). Sagittal otoliths were processed, and thermal mark code patterns were resolved to identify marking facilities and release sites. Many of the pink (45), chum (483), and sockeye (12) salmon examined contained thermal marks. Most recovered cwt’s and thermal marks originated in southeastern Alaska. Most thermally marked juveniles had migrated 100–150 km in 60–90 days from release locations in northern and central southeastern Alaska and were recaptured along a primary migration corridor in northern southeastern Alaska. The high proportion (15.1%) of otolith thermal mark recoveries has broad implications for the study of Pacific salmon life histories. In particular, systematic sampling for thermal marks may provide stock-specific insight into the early marine life histories of Pacific salmon species, especially pink and chum salmon, which otherwise are underrepresented in cwt recoveries.

Thermal Marking of Otoliths in Lake Trout Sac Fry

The ability to distinguish hatchery-produced lake trout Salvelinus namaycush from their wild counterparts is essential for evaluation of restoration efforts in Lake Superior. However, when early life history stages are stocked, conventional external marking procedures are inappropriate. The use of thermal marks in otoliths has become an accepted procedure for fry of Pacific salmon Oncorhynchus spp., but knowledge of the technique with lake trout fry is limited. This study adds to existing knowledge of thermal marking with insight into factors that affect lake trout. Several thermal marking regimes with lake trout sac fry were evaluated by varying the number, range, duration, and spacing of temperature pulses. Pulses produced individual bands on otoliths that together constituted the mark. Mark visibility varied within treatments, but in general, the highest quality marks were achieved when fry were subjected to pulses of 10°C or higher for 8 h or more on alternate days. These marks were visible on fry otoliths at 40× magnification, and individual bands were visible at 100×. Higher magnification was needed to distinguish individual bands when fish were marked with consecutive-day pulses. As fish grew older, 200× magnification was required to distinguish consecutive-day bands. Precision in preparing otoliths for examination was also a factor governing mark visibility, but the better marks were visible with less preparation. Marked fish are currently being maintained in our hatchery until maturity, and mark recognition has been 100% for up to 7 years. Nearly 1.5 million marked lake trout sac fry were released on a reef in Lake Superior during the 3-year period 1994–1996, and mark evaluation of lake trout captured in this location will be attempted in the future.

Thermal Marking of Atlantic Salmon Otoliths

By exposing fry of Atlantic salmon Salmo salar to various temperature regimes, we determined conditions required to produce a readable thermal otolith mark. Marks were quantified by using a darkness index that represented the number of times darker the mark was than the background. Minimum requirements for a strong mark were 1 d at a relatively warm premark temperature of 9°C and 8 h at a lower marking temperature (1°C). Temperature decreases of 4°C (from 5°C to 1°C) resulted in strong marks if fish were held at the premark temperature for 4 d and at the marking temperature for at least 24 h.

Oxytetracycline Marking Efficacy for Yellow Perch Fingerlings and Temporal Assays of Tissue Residues

Differentiating between hatchery and naturally reproduced fishes is difficult because of the lack of appropriate marking techniques. Chemical immersion techniques can be a practical method for mass marking juvenile fishes. The objectives of this study were to determine the concentration of oxytetracycli ne (OTC) hydrochloride needed to effectively mark age-0 yellow perch Perca flavescens. to observe the retention lime of the mark, and to measure the persistence of OTC in body tissues. Fish were immersed in 309, 534, and 748 mg OTC/L for 12 h. Initial fish collections were made weekly, and monthly collections began 1 month postmarking for tissue and mark analyses. High-pressure liquid chromatography was used to quantitate OTC residues in tissues; OTC concentrations were undetectable (<0.05 jxg/g) in the edible tissue (muscle) at 110 d postimmersion. Aided by a Nikon Labophot fluorescence microscope, we discerned otolith marks 56 d postimmersion on 100% of the fish treated at 534 and 748 mg/L. Marks were still visible on 100% of the fish treated with 534 and 748 mg/L at 8 months postimmersion.

Evaluation of Oxytetracycline Marks in Sagittal Otoliths of Juvenile Black Crappies

Abstract We validated oxytetracycline (OTC) mark production in the sagittal otoliths of juvenile black crappies Pomoxis nigromaculatus. Black crappies were marked en masse by immersion in a 500-mg oxytetracycline hydrochloride/L solution for 6 h. The exposure to OTC did not diminish survival over 31 weeks. The technique effectively marked 88% of the black crappies, based on observations of one sagitta from each fish. Only 2% of the control black crappies were incorrectly classified as marked, and observer experience did not affect correct classification rate. Because we marked fish late in the growing season, the marks appeared in the annulus; OTC marks applied when fish are growing faster may be more readily discernable.

Use of a Bar Code Symbology to Produce Multiple Thermally Induced Otolith Marks

From 1987 to 1993, the Washington Department of Fisheries mass-marked over 35 million juvenile salmonids by inducing unique banding patterns into their otoliths by means of short-term water temperature changes during incubation. All five species of Pacific salmon Oncorhynchus spp. were successfully marked, and several broods of returning adults have demonstrated the persistence of these marks for at least 5 years. Using systematic rules developed in the bar code industry and a marking pattern of six bands and five spaces, we created a method for producing up to 10 different bar codes for marking the otoliths of incubating salmonids. Multiple groups (N) of six bands can produce 10N different codes. Ten unique patterns were decoded, both visually and with the aid of a computerized image-analysis system combined with a decoding algorithm. Repeated blind tests showed that pattern recognition was virtually error free with both methods. Because the symbology is based upon the relative spacing of bands, the pattern can be discerned along any clear otolith axis; a consistent otolith measurement axis or section plane is not required. As a result, relatively gross, rapid otolith preparation procedures were adequate for accurate pattern recognition. Although the decoding algorithm may result in a failure to decode, the likelihood of misclassifications is small due to restrictive rules in the bar code symbology. Many research and management applications of thermal mass-marking require the use of a number of unique patterns. This bar code method provides a simple means of organizing information so that multiple unique patterns are easily distinguished. Although demonstrated on chinook salmon Oncorhynchus tshawytscha, this method is applicable to any species for which thermal marking of otoliths is appropriate.

Effects of release size on survival and growth of Japanese flounder Paralichthys olivaceus in coastal waters off Iwate Prefecture, northeastern Japan

A total of 35900 in 1990 and 73400 in 1991 otolith-marked, hatchery-raised Japanese flounder Paralichthys olivaceus fry ranging from 4 to 15 cm total length (TL) were released into shallow water at depths of 4 to 8 m at Ohno Bay, northeastern Japan. The otoliths of the fish were marked 1 to 3 d prior to release with an alizarin complexone fluorescent marker The size at release of flounder recaptured by a beam trawl, set net and commercial catch was estimated using the fluorescent mark diameter to TL relationship, and survival and growth rates were examined. As time progressed after release, back-calculated release size distributions gradually shlfted to larger values. The flounder fry > 9 cm at release were successful in recruiting to commercial fisheries. The major cause of mortality was thought to be predation by large flounder and greenling Hexagrammos otaku whlch were abundant in the flounder nursery ground. Growth rate of released flounder was high in the warm and low in the cold season. Individual growth rates were estimated by otolith mark diameter and TL at catch. The relationship of release size and growth rate analyzed in the flounder recaptured 1 1 mo after release indicated that survival of released flounder is strongly associated with size itself and growth rate in the field.

Technical Notes: A Hatchery Water-Heating System and its Application to 100% Thermal Marking of Incubating Salmon

Abstract The components and general operation of a system for heating incubation water for thermal marking of salmon otoliths are presented. The system was operated at the Gastineau Salmon Hatchery in Juneau, Alaska, to simultaneously mark 33 million eggs and alevins of pink salmon (Oncorhynchus gorbuscha) during fall 1990. Water temperatures were controlled to ±0.1°C. No mortality of or apparent stress on the fish was observed.

Validation of age estimates in sparid fish using flubrochrome marking

The marking of sparid otoliths by means of oxytetracycline and alizarin complexone was investigated by immersion, feeding and intraperitoneal and intramuscular injections. Of these techniques, immersion for 24 h in a 100–150 mg·ℓ−1 seawater solution of alizarin complexone was found to be most suitable for marking larval and small juvenile fish. Intramuscular injections of oxytetracycline at a dosage of 250 mg·kg fish−1 was the most suitable method for marking the otoliths of juveniles in the laboratory, while dosages between 50 and 100 mg·kg fish−1 were used to mark adults in the field. Feeding labelled food to the fish and intraperitoneal injections did not produce a clear mark in the otolith. Fluorochrome marks confirmed the daily periodicity of micro-increment formation in some captive sparid species (Diplodus sargus and D. cervinus), and field experiments using Chrysoblephus laticeps showed that this method was a relatively simple way of directly validating age estimates in sparid fish.

Validation of annual marks in the Otoliths of young Snapper, Pagrus auratus (Sparidae)

In April 1989, young-of-the-year snapper (Pagrus auratus) were captured from the wild and injected with tetracycline. The fish were reared on natural food in a large pool with flowing sea water under ambient marine conditions. Two fish were removed every two months for two years, and the growth of their otoliths, relative to the tetracycline mark, was measured. Growth of the otoliths was greatest in spring and summer and least during winter. Opaque marks appeared in the otoliths of fish during both winters of the study. Our results confirm that the opaque marks in otoliths of young snapper can be used to determine the age of the fish in years.

Tetracycline marking of coregonids at the time of egg fertilization

Tetracycline marking of otoliths can be achieved by osmotic importation at fertilization when hardening is conducted in tetracycline solutions. Marks produced are recognizable even in fish of catchable size without a very extensive otolith preparation. The method can contribute to estimations of stocking efficiency and to discern recruits of natural and artificial reproduction.

Effect of Sunlight on Tetracycline Marks in Otoliths of Colorado Squawfish Larvae

Abstract Embryos and newly hatched larvae of Colorado squawfish Ptychocheilus lucius were immersed in tris-buffered solutions of 350 mg tetracycline hydrochloride (TC)/L of distilled water for 24 h (embryos) or 12 h (larvae). Larvae from both treatments were held indoors prior to swim-up and indoors or outdoors for 7 d after swim-up. Exposure to sunlight under simulated natural conditions had no detectable effect on quality or retention of fluorescent TC marks in otoliths. Marks in all otoliths examined were distinct and lucid to bright. Mark-recapture studies on age-0 Colorado squawfish could facilitate research needed for applied management and population recovery. Tetracycline marks in otoliths appear to be suitable for this purpose.

Multiple Marking of American Shad Otoliths with Tetracycline Antibiotics

–Techniques for mass marking of otoliths of hatchery-reared American shad Alosa sapidissima with tetracycline (TC) antibiotics were refined to include multiple marks produced by immersion of fry or by feeding TC compounds to fingerlings. Single, double, triple, or quadruple marks were produced in fry by immersion in 200 mg tetracycline or oxytetracycline/L for 6 h at 4-d intervals. Single, double, and triple marks were produced in fingerlings by feeding 88 g of tetracycline/kg of food for three consecutive days, at 5- or 7-d intervals. Unique combinations of marks produced by immersion in or feeding of TC compounds can be used to evaluate the success of hatchery releases and to refine hatchery effort to maximize returns.

Age and Growth of Atlantic Croakers in the Northern Gulf of Mexico, Based on Otolith Sections

Otoliths from 1,291 Atlantic croakers Micropogonias undulatus, with total lengths from 113 mm to 417 mm, from the northern Gulf of Mexico were examined to determine age and growth. Marginal increment analysis was used to determine that otolith marks formed annually. Ages ranged from 0 to 8 years. No significant difference was found for length at age between males and females. The von Bertalanffy equation was Lt = 419.2[1 - e−0.273(t+1.405)], where Lt = total length (mm) and t = age (years). The length-weight relationship (r = 0.99) was W = 5.302 × 10−6TL3.134 where W = weight (g) and TL = total length (mm).