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Tag-recapture data contain valuable information about individual fish growth, which can enhance the estimation of growth parameters. Tag-recapture data are especially useful when age-determination uncertainties throw age-based growth estimates and stock assessments into question, as is the present situation with several important gadoid stocks. Length-based (GROTAG method) and age-based (LEP method) growth functions were fit to a large data set of tagged and recaptured cod (Gadus morhua) from an artificial reef in the western Baltic Sea to calculate improved growth parameter estimates. The LEP method allowed integration of different data formats, including tag-recapture, length frequency, and length-at-age, to estimate a more robust and comprehensive growth function (von Bertalanffy growth parameters: [L.sub.[infinity]] = 154.56 cm, k = 0.11, [t.sub.0] = -0.13). Two heavily exploited cod stocks inhabit the Baltic Sea, subsisting at the upper thermal and lower salinity limits of the species. Otolith shape analyses indicated that, unexpectedly, individuals from both populations were resident at the reef. Compared with cod populations elsewhere, cod in the western Baltic Sea grow relatively slowly and with weak seasonal fluctuations in growth rates, potentially due to adverse conditions for growth. Les donnees de marquage-recapture contiennent de l'information utile sur la croissance individuelle des poissons qui peut ameliorer l'estimation des parametres de croissance. Ces donnees sont particulierement utiles quand les incertitudes associees a la determination de l'age jettent un doute sur les estimations de la croissance et les evaluations de stock basees sur l'age, comme c'est actuellement le cas pour plusieurs stocks importants de gadides. Des fonctions de croissance basees sur la longueur (methode GROTAG) et sur l'age (methode LEP) ont ete calees sur un grand ensemble de donnees de morues (Gadus morhua) marquees et recapturees d'un recif artificiel dans l'ouest de la mer Baltique afin d'obtenir de meilleures estimations des parametres de croissance. La methode LEP a permis l'integration de differents formats de donnees, dont des donnees de marquage-recapture, de frequence de longueurs et de longueur selon l'age, pour estimer une fonction de croissance plus robuste et complete (parametres de croissance de von Bertalanffy : [L.sub.[infinity]] = 154,56 cm, k = 0,11, [t.sub.0] = -0,13). Deux stocks de morues faisant l'objet d'une exploitation intensive sont presents dans la mer Baltique, ou ils subsistent a la limite de temperature superieure et a la limite de salinite inferieure de l'espece. Des analyses de la forme d'otolites indiquent que, contrairement aux attentes, des specimens des deux populations sont des residents du recif. Comparativement aux populations de morues en d'autres endroits, la morue de l'ouest de la mer Baltique a une croissance relativement lente caracterisee par de faibles fluctuations saisonnieres, possiblement a cause de conditions non propices a la croissance. [Traduit par la Redaction], Introduction Estimating individual growth of fish has been a central theme in fisheries science for decades, as an intrinsic characteristic of a fish population and an essential component of stock [...]

Some studies have demonstrated that elevated C[O.sub.2] concentrations in ocean waters negatively impact metabolism and development of marine fish. Particularly, early developmental stages are probably more susceptible to ocean acidification due to insufficient regulations of their acid-base balance. Transgenerational acclimation can be an important mechanism to mediate impacts of increased C[O.sub.2] on marine species, yet very little is known about the potential of parental effects in teleosts. Therefore, transgenerational effects were investigated on life history in juvenile three-spined sticklebacks Gasterosteus aculeatus by acclimating parents (collected in April 2012, 55°03/N, 8°44'E) and offspring to ambient (~400 patm) and elevated (~1,000 µatm) C[O.sub.2] levels and measured parental fecundity as well as offspring survival, growth and otolith characteristics. Exposure to elevated C[O.sub.2] concentrations led to an increase in clutch size in adults as well as increased juvenile survival and growth rates between 60 and 90 days post-hatch and enlarged otolith areas compared with fish from ambient C[O.sub.2] concentrations. Moreover, transgenerational effects were observed in reduced survival and body size 30 days post-hatch as well as in enlarged otoliths at the end of the experiment, when fathers or both parents were acclimated to the high-C[O.sub.2] environment. These results may suggest that elevated C[O.sub.2] concentrations had rather positive effects on life-history traits of three-spined sticklebacks, but that parental acclimation can modify these effects without improving offspring fitness. Although the mechanistic basis of such transgenerational acclimation remains unclear, selective gradients within generations seem to determine the direction of transgenerational effects., Introduction Approximately one-third of the constantly increasing atmospheric carbon dioxide (C[O.sub.2]) is dissolved in marine waters causing a decline in ocean pH and leading to an acidification of the ocean [...]