This paper shows the fish otolith function and its formation and introduces some validation methods, including: rearing fish, mark and release, radiometric assessment, assays of bomb radiocarbon, counting daily increments between annuli, length-frequency modes and validating the first growth increment. | Journal of Marine Science and Technology; Vol. 14, No. 3; 2014: 246-254 DOI: THE ACCURACY OF FISH OTOLITH ANALYSIS AND SOME VALIDATION METHODS Do Huu Hoang Institute of Oceanography-VAST Email: dohuuhoang2002@ Received: 29-3-2014 ABSTRACT: Age structure and growth of fish are the extremely important data in fishery management. The data help policy makers have good strategies to manage and catch fish more effectively and sustainably. Although there are many studies on fish age determination based on otolith, the methods are still essential to be validated for each species, each method and studied area, because fish otolith formation is affected by many endogenous and exogenous factors. This paper shows the fish otolith function and its formation and introduces some validation methods, including: rearing fish, mark and release, radiometric assessment, assays of bomb radiocarbon, counting daily increments between annuli, length-frequency modes and validating the first growth increment. Keywords: Otolith, age determination, growth, validation methods. INTRODUCTION Age determination is very important in fisheries researches. Age information combined with length of fish, fecundity, spawning season and fishery data, are used to build reliable stock assessments. With age data, fisheries managers can choose from reasonable models to ultimately determine the impact of a fishery, and these model predictions are the basis of catch and effort regulations. There are many methods to estimate age of the fish and aquatic organisms such as length frequency analysis, mark-recapture, or hard part analyses [1-5]. Hard part analyses are more accurate and precise which are based on the hard parts of animals such as scales of fish, fish bone, opercula, spines or fin rays, or otoliths, the shells of bivalves and gastropods or the statoliths of squids. Otolith of fish has been increasingly used in fisheries study .
