The use of otolith shape and morphometry for identification and size-estimation of five wrasse species in predator-prey studies

Abstract

Sagittal otoliths of five wrasse species, Coris julis, Symphodus tinca, Symphodus cinereus, Symphodus ocellatus and Symphodus rostratus from the eastern Adriatic were compared using descriptive morphological characters (types of anterior and posterior otolith regions and otolith margins) and shape indices (formfactor, roundness, circularity, rectangularity and elipticity). All shape indices except the formfactor were used to build the discriminant function, with circularity and roundness being the main variables that explain the interspecific variability. The overall classification score of the discriminant analysis was 62.8%, with the lowest score obtained for S. ocellatus (44.3%) and the highest for C. julis (83.3%). Otolith morphometric parameters (length, width, thickness and weight) were used in predictive linear regression equations to estimate fish size. For all investigated wrasses, except for S. rostratus, otolith length showed the strongest and otolith thickness the weakest relationship to both fish length and weight. Multiple linear regression equations based on log transformed variants explained higher proportion of variation in fish size than simple linear regressions, although these differences in R 2 were relatively low, amounting to 1.3-12.1% when compared to the best simple regressions for different species.

Relationships between fish length and otolith size for five cyprinid speciesfrom Lake Ladik, Samsun, Turkey

“…Otolith biometrybody length relationships were defined using linear models for various fish species (Echeverria, 1987;Şahin and Güneş, 1998;Harvey et al, 2000;Şen et al, 2001;Morley and Belchier, 2002;Bostancı, 2009;Battaglia et al, 2010;Zorica et al, 2010;Jawad et al, 2011;Bostancı et al, 2012;Basusta et al, 2013;Felix et al, 2013). However, nonlinear models were used to generate the mentioned relationships for some fishes (Waessle et al, 2003;Kumar et al, 2012;Skeljo and Ferri, 2012). In this study, curvilinear and linear functions provided the best fit for 80% and 20% of all species, respectively.…”

“…Otolith length (the greatest distance between anterior and posterior otolith margin) and otolith width (the greatest distance from dorsal to ventral otolith margin for the asteriscus and from lateral to medial margin for the lapillus) were measured to the nearest 0.001 mm using Leica Application Suit Ver. 3.8 Imaging Software (Skeljo and Ferri, 2012). The right and left otoliths were considered separately.…”

“…However, useful information can only be obtained from the otoliths if the relationship between otolith size and fish size is generated (Morley and Belchier, 2002;Longenecker, 2008). Otolith biometry-body length relationships have been determined for many fish species by different investigators (Gamboa, 1991;Harvey et al, 2000;Waessle et al, 2003;Longenecker, 2008;Battaglia et al, 2010;Zorica et al, 2010;Potier et al, 2011;Skeljo and Ferri, 2012). In Turkey, although a number of studies have been reported on relationships between otolith size and fish length (Şahin and Güneş, 1998;Can, 2000;Ceyhan and Akyol, 2006;Samsun and Samsun, 2006;Bostancı and Polat, 2008;Eroğlu and Şen, 2009;Bostancı et al, 2009;Bostancı et al, 2012;Cengiz et al, 2012;Basusta et al, 2013;Bilge, 2013;İşmen et al, 2013), such information is still lacking for many members of the ichthyofauna.…”

Morphological and Biometrical Characteristics on Otolith of Barbus tauricus Kessler, 1877 on Light and Scanning Electron Microscope

“…For instance, FL-WO relationship (r 2 = 0.651) is lower than FL-OL relationship (r 2 = 0.751) for Engraulis encrasicolus (Zorica et al, 2010). The similar results were shown for Coris julis (FL-OL (r 2 )= 92.7, FL-WO (r 2 )= 88.2), Symphodus tinca (FL-OL (r 2 )= 86.5, FL-WO (r 2 )= 80.6), Symphodus cinereus (FL-OL (r 2 )= 57.3, FL-WO (r 2 )= 52.4), Symphodus ocellatus (FL-OL(r 2 )= 51.6, FL-WO (r 2 )= 44.7) (Skeljo & Ferri, 2012). In addition, similar results for one of the Cyprinid fish Capoeta banarescui, which is a freshwater fish, were shown that the relationship between total length and otolith weight (r 2 =0.56) is lower than the other relationships between otolith length (r 2 = 0.88) and otolith width (r 2 = 0.83) (Keskin).…”

KARAKTERISTIKMORFOLOGI DANHUBUNGANMORFOMETRIK OTOLITH DENGAN UKURAN IKAN LEMURU (Sardinella lemuru Bleeker, 1853) DI SELAT BALI

“…Penelitian hubungan antara morfometrik otolith dan ukuran ikan sangat berguna untuk mengestimasi ukuran riil individu ikan yang telah tercerna, baik panjang dan beratnya, sebagai pendukung dalam kajian hubungan pemangsa dan mangsa (predator and prey relationship) (Granadeiro & Silva, 2000;Skeljo & Ferri, 2012). Hubungan antara morfometrik otolith dan ukuran ikan dapat digunakan untuk penghitungan balik (back-calculation) ukuran ikan yang telah dimangsa/tercerna (Zan et al, 2015).…”