Bu araştırma; mezgit balığının, Merlangius merlangus yıllık beslenme beslenme
rejimini ve kanibalist davranış özelliklerini araştırmak için Eylül 2016-Ağustos 2017
tarihleri arasında Güney-doğu Karadeniz’in Ordu ve Samsun kıyılarında
yürütülmüştür. Araştırmanın mezgit balığı örnekleri aylık olarak ticari avcılıktan elde
edilmiştir. Araştırma süresince incelenen 762 mezgit balığı midesinden %75.7’sinin
boş olduğu tespit edilmiştir. Mezgit balıklarının midelerinde 5 balık (istavrit, hamsi,
çaça mezgit ve kayabalığı) ve bir Gastropod türüne rastlanmıştır. Balık türlerinden
istavrit, mezgit balıklarının hem Ordu hem de Samsun kıyılarında en önemli besin
kaynağını oluşturduğu tespit edilmiştir. Bu balık türünü hem Ordu hem de Samsun
kıyılarında sırasıyla hamsi ve mezgit izlemiştir. Ancak, Samsun kıyılarında yaşayan
mezgit balıkları için besin kaynağı olarak kendi türünün önemi Ordu kıyılarında
yaşayan mezgit balıklarına göre çok daha düşük bulunmuştur. Başka bir ifadeyle,
Samsun kıyılarında kanibalizm oranı Ordu kıyılarına göre çok daha düşük
bulunmuştur. Güney-doğu Karadeniz’de mezgit balıkları arasında kanibalizm oranı
%12 IRI ve %14 PRIV olarak tespit edilmiştir. İlkbahar ve sonbahar mevsimindeki
kanibalizm oranı yaz ve kış dönemlerine göre daha düşük bulunmuştur. Mezgit
balıklarının ilkbahar ve yaz mevsimlerindeki en önemli besin kaynağını istavrit
balığı iken, sonbahar ve kış mevsimlerinde hamsi olduğu saptanmıştır. Bu balık
türlerini ilkbahar ve yaz mevsimlerinde mezgit, sonbahar mevsiminde mezgit ve
istavrit, kış mevsiminde ise istavrit ve mezgit balığı izlemiştir. Bu sonuçlar, mezgit
balığının besin kaynaklarındaki azalmaya bağlı olarak ilkbahar ve yaz aylarında
kanibalizme yöneldiğini göstermektedir. Mezgit balıklarının, boylarının Ordu
kıyılarında %37.6’sı, Samsun kıyılarında %24.3’ü kadar büyüklükteki kendi türünün
bireylerini tükettikleri saptanmıştır. Mezgit balıklarının ağırlıklarının, Ordu
kıyılarında %11.2’si, Samsun kıyılarında ise %8’i kadar olan kendi türünün
bireylerini tükettikleri belirlenmiştir.,The study was conducted in the coasts of Ordu and Samsun of the south-eastern
Black Sea between September 2016 and August 2017, to investigate the cannibalistic
behavioral characteristics of the whiting.Whiting samples were obtained monthly
from commercial fishing. During the study, 75.7% of 762 haddock stomachs were
found to be empty.In the stomach of whiting, five fish species (horse mackerel,
anchovy, sprat haddock and goby) and a Gastropod species were determined. It is
determined that horse mackerel was the most important food source both in Ordu and
Samsun coasts. This food source was followed by the anchovy and the whiting in the
both sampling areas, respectively.However, the importance of its own species as a
food source for whiting on the Samsun coasts was found to be much lower than the
whiting on the Ordu coasts.In other words, the rate of canibalism was found to be
much lower on the Samsun coasts than the Ordu coasts.In the south-eastern Black
Sea, the rate of cannibalism among whiting fish was found to be 12% IRI and 14%
PRIV. The rate of canibalism in spring and autumn was lower than in summer and
winter.The rate of canibalism in spring and autumn was lower than in summer and
winter. While the most important food source of the whiting in spring and summer
was the mackerel fish, the anchovy in the autumn and winter seasons.These fish
species was followed by haddock in spring and summer, whiting and horse mackerel
in autumn and horse mackerel and haddock in winter.These results show that the
whiting tends to cannibalism in spring and summer due to the decrease in food
sources.It was determined that whiting fish consumed individuals belonging to their
own species as large as 37.6% of their lengths in the Ordu coasts, 24.3% in the
Samsun coasts.The whiting consumed individuals of their own species which were
up to 11.2% of their weight in the Ordu coasts and 8% in the Samsun coasts.
The study was conducted in the coasts of Ordu and Samsun of the south-eastern
Black Sea between September 2016 and August 2017, to investigate the cannibalistic
behavioral characteristics of the whiting.Whiting samples were obtained monthly
from commercial fishing. During the study, 75.7% of 762 haddock stomachs were
found to be empty.In the stomach of whiting, five fish species (horse mackerel,
anchovy, sprat haddock and goby) and a Gastropod species were determined. It is
determined that horse mackerel was the most important food source both in Ordu and
Samsun coasts. This food source was followed by the anchovy and the whiting in the
both sampling areas, respectively.However, the importance of its own species as a
food source for whiting on the Samsun coasts was found to be much lower than the
whiting on the Ordu coasts.In other words, the rate of canibalism was found to be
much lower on the Samsun coasts than the Ordu coasts.In the south-eastern Black
Sea, the rate of cannibalism among whiting fish was found to be 12% IRI and 14%
PRIV. The rate of canibalism in spring and autumn was lower than in summer and
winter.The rate of canibalism in spring and autumn was lower than in summer and
winter. While the most important food source of the whiting in spring and summer
was the mackerel fish, the anchovy in the autumn and winter seasons.These fish
species was followed by haddock in spring and summer, whiting and horse mackerel
in autumn and horse mackerel and haddock in winter.These results show that the
whiting tends to cannibalism in spring and summer due to the decrease in food
sources.It was determined that whiting fish consumed individuals belonging to their
own species as large as 37.6% of their lengths in the Ordu coasts, 24.3% in the
Samsun coasts.The whiting consumed individuals of their own species which were
up to 11.2% of their weight in the Ordu coasts and 8% in the Samsun coasts.
