Aquaculture Studies 2012, Vol 12, Num, 4     (Pages: 006-012)

Comparison of Whole Otolith and Broken-Burnt Otolith Ages of Mediterranean Horse Mackerel (Trachurus mediterraneus Steindachner, 1868)

Elvan ATILGAN 1 ,Murat ERBAY 1 ,Nimet Selda BASÇINAR 1

1 Su Ürünleri Merkez Araştırma Enstitüsü, Vali Adil Yazar Cad., No/14, Kaþüstü Beldesi, 61250 Yomra, Trabzon, Türkiye DOI : 10.17693/yunusae.v2012i21907.235429 Viewed : 3141 - Downloaded : 2574 In this study, whole otolith ages and broken-burnt otolith ages of 153 horse mackerel (T. mediterraneus) that provide with purse seine fishery in Southeastern Black Sea (Ordu-Rize) were determined and similarities and differences were compared. Otoliths were read once by three readers and mean age in whole otolith and broken-burnt readings are respectively calculated as 2,29 and 2,45. Annulus could not read in 10 of the whole otoliths before broken-burnt process but in the same otoliths, annulus could read after the broken-burnt process. Age differences between the two methods found out as 2 at most. Consistence ratio between two methods (no differerence in readings between two methods) 75,52% and inconsistency ratio determined as 23,77% for age difference 1 and 0,69% for age difference 2. As a result, horse mackerel otoliths are recommended to read as a whole but breakburn method is recommended to interpret difficult otoliths. Keywords : Southeastern Black Sea, break-burn method, T. mediterraneus, otolith, age estimation