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Stomach contents of 296 juvenile chub mackerel (Scomber japonicus Houttuyn, 1782) specimens were examined based on samplings carried out in Izmir Bay (Aegean Sea, Turkey) during 2001. In terms of percentage weight (W%), fishes were the main food during summer and autumn. Thaliaceans (Salpa sp.) constituted the most important food source in winter, whereas planktonic crustaceans (Amphipoda, Copepoda) were the main prey during spring. According to the Bray-Curtis similarity index, diet of the chub mackerel was 64.1% similar during the summer, winter and autumn seasons.

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The present study was conducted to determine the age relationships in lengths and weights of Boops boops (Linneaus, 1756) in Izmir Bay, central Aegean Sea. A total of 932 specimens (503 females and 429 males) were caught by gillnet, trammel net and a combination thereof on a monthly sampling basis from November 2008 through October 2009. Total length and weight of sampled fish ranged from 11.3 to 27.9 cm and from 12.2 to 261.7 g, with a mean of 19.6 cm and 82.7 g, respectively. Length-weight relationships for all individuals were described by the parameters a = 0.0050, b = 3.237 and r² = 0.956. The von Bertalanffy growth curve fitted to the lengths-at-age provided parameters of L ∞ = 29.87 cm k = 0.243 and t o = À0.98 for males and L ∞ = 30.79 cm, k = 0.239 and t o = À0.90 for females. Based on otolith readings, age determinations varied from 1 to 5 years. Maximum age was 5 years in age group 2, with 29.84 and 37.97% for males and females, respectively. The overall 1 : 1.17 sex ratio of males to females was significantly biased toward females (P < 0.05). There was no statistical difference in the mean condition factor (P > 0.05), with a value of 1.028 for the entire population. The growth performance index (Φ ' ) was 2.33 and 2.36 for males and females, respectively. Results were similar to other geographical areas, which suggests that a common fisheries management might be possible.

Three fish species, Bregmaceros atlanticus Goode et Bean, 1886 (Bregmacerotidae), Echiodon dentatus (Cuvier, 1829) (Carapidae), and Nemichthys scolopaceus Richardson, 1848 (Nemichthyidae) were recorded in the Sığacık and Kuşadası Bays (Eastern Aegean Sea, Turkey). B. atlanticus and E. dentatus constitute new records for the Turkish waters and the Aegean Sea, respectively. The finding of Nemichthys scolopaceus is the second record for the Aegean Sea.

Summary The objective of this study was to determine the monthly dietary pattern in migratory garfish and to improve our understanding in the seasonality of prey choice. Gut contents of 597 Belone belone specimens collected from the eastern Aegean Sea (Turkey) were analyzed: 79.2% contained food in their guts and 20.8% had empty guts. Crustaceans (36.7%) were the most important prey with a 36.7 index of relative importance (%IRI). Especially brachyurans (13.0%) and copepods played a major role (10.1%), followed by teleosts (26.1%) and other food categories (23.3%) (much of which was of terrestrial origin, including insects). Nannocalanus minor, Clausocalanus arcuicornis, Temora stylifera, Labidocera wollastoni and Oncea media were important copepods found in the guts of B. belone specimens. Analysis of variance of the monthly weight data indicated no significant seasonal differences, except for January and February.

Ege Denizi'nde bulunan beş derin deniz balığı: Argentina sphyraena, Glossanodon leioglossus, Chlorophthalmus agassizi, Hoplostethus mediterraneus ve Capros aper 2003 bahar mevsimi süresince ticari trol balıkçıları tarafından hedef dışı av olarak elde edilen örnekler olarak çalışılmıştır. Türlerin besin kompozisyonlarını belirlemek için mide içerikleri incelenmiştir ve türlerin trofik durumlarının özellikle karnivor seviyede yer aldığı görülmüştür. Beş predator türün besin kompozisyonunda iki esas av grubu bulunmuştur: Crustacea (copepodlar ve isopodlar gibi) ve Chaetognatha (Sagitta spp.).

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