Determining density of Caulerpa racemosa (forsskål) J. Agardh and its effects on catch compositions of fishing gears
Küçük Resim Yok
Tarih
2011
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu çalışmada, Caulerpa racemosa’nın farklı derinliklere bağlı yoğunluk değişimi ve bu yoğunluk dağılımının, av kompozisyonunda balık tür çeşitliliğine olan etkisi araştırılmıştır. C racemosa’nın derinliğe bağlı yoğunluk değişimi, balıkadamlar tarafından Scuba dalış yapılarak quadrat yöntemiyle; balık tür çeşitliliğine olan etkisi, görsel sayım yöntemi ve kombine uzatma ağları avcılığıyla belirlenmiştir. Çalışma Eylül 2005-Mart 2007 tarihleri arasında Ege Denizi doğu kıyılarında yürütülmüştür. Örnekleme dalışları sonucunda C. racemosa yoğunluğu, 0-5, 6-10, 11-15, 16-20, 21-25 m derinlik konturlarında sırası ile 135,4, 146,5, 191,3, 385,7 ve 635,1 g/m² bulunmuştur. Balık türlerinin örneklenmesi amacıyla kombine uzatma ağları ile 14 av operasyonu gerçekleştirilmiştir. C. racemosa kaplı alanda 13 türe ait 293 birey yakalanırken kontrol bölgesinde, 16 türe ait 322 birey yakalanmıştır. Her iki alanda, yakalanan birey sayıları açısından fark bulunmamıştır (P>0,01). Görsel sayım yönteminde C. racemosa ile kaplı alanda 5 türe ait 24 birey tespit edilirken, kontrol bölgesinde 5 türe ait 32 birey tespit edilmiştir. Her iki alanda gözlenen birey sayıları açısından önemli bir fark bulunmamıştır (P>0,01). Sonuç olarak bu çalışma Türkiye kıyılarında gözlenen yayılımcı alg türünün yayılım yoğunluğu ve balıkçılık av kompozisyonuna etkileri konusunda ilk sonuçları içermektedir. Bu türün yayılım alanında izlenmesi ve diğer türler üzerinde etkilerinin gözlenmesi, balıkçılık yönetimi ve ekosistem açısından son derece önem arz etmektedir.
In this study, the variation of Caulerpa racemosa density depending on different depths and its effects on the diversity of some fish species in catch composition were investigated. the quadrate method was used by divers to determine the variation of density of C. racemosa depending on depth and its possible effects on fish species diversity was determined by visual census method and combined trammel nets. the study was conducted during the periods September 2005 and March 2007 from the Eastern Aegean coast. As a result of sampling dives, density of C. racemosa was found as 135.4, 146.5, 191.3, 385.7 and 635.1 g/m² at the depth ranges of 0-5, 6-10, 11-15, 16-20 and 21-25 m, respectively. 14 fishing operations were performed to sample fish species by using combined trammel nets. 293 individuals belonging to 13 species from the area covered by C. racemosa and 322 individuals belonging to 16 species from the control area were caught. Any variation was not found in terms of fish number sampled from those areas (P>0.01). 24 individuals belonging to 5 species and 32 individuals belonging to 5 species were censused from the area covered by C. racemosa and the control site, respectively. the differences between the number of fish sampled from those sites was found insignificant (P>0.01). Consequently this study contains the first results about invasion density of the invasive alga species seen in Turkish coasts and its effects of fish composition. It is very important to monitor this species in the invasion area and to observe its effects on other species for fishing management and the ecosystem.
In this study, the variation of Caulerpa racemosa density depending on different depths and its effects on the diversity of some fish species in catch composition were investigated. the quadrate method was used by divers to determine the variation of density of C. racemosa depending on depth and its possible effects on fish species diversity was determined by visual census method and combined trammel nets. the study was conducted during the periods September 2005 and March 2007 from the Eastern Aegean coast. As a result of sampling dives, density of C. racemosa was found as 135.4, 146.5, 191.3, 385.7 and 635.1 g/m² at the depth ranges of 0-5, 6-10, 11-15, 16-20 and 21-25 m, respectively. 14 fishing operations were performed to sample fish species by using combined trammel nets. 293 individuals belonging to 13 species from the area covered by C. racemosa and 322 individuals belonging to 16 species from the control area were caught. Any variation was not found in terms of fish number sampled from those areas (P>0.01). 24 individuals belonging to 5 species and 32 individuals belonging to 5 species were censused from the area covered by C. racemosa and the control site, respectively. the differences between the number of fish sampled from those sites was found insignificant (P>0.01). Consequently this study contains the first results about invasion density of the invasive alga species seen in Turkish coasts and its effects of fish composition. It is very important to monitor this species in the invasion area and to observe its effects on other species for fishing management and the ecosystem.
Açıklama
Anahtar Kelimeler
Balıkçılık, Zooloji
Kaynak
Turkish Journal of Fisheries and Aquatic Sciences
WoS Q Değeri
Scopus Q Değeri
Cilt
11
Sayı
3
