On the Use of Otoliths of a Ponto-Caspian gobiid Proterorhinus marmoratus (Pallas, 1814) from Lake İznik (Turkey) in Prey-Predator Studies

Abstract

The regression relationships between otolith morphometric parameters and body size in tubenose goby Proterorhinus marmoratus (Pallas, 1814) captured from Lake İznik in October 2004 were researched and determined. The equations were used to reconstruct the original dimensions of prey from the size of hard structures found in food samples of piscivorous predators living in, or in the vicinity of, the aquatic habitat. The relationships between the chosen hard structure and body length were described with various linear or non-linear equations. All calculated regressions were highly significant (P<0.001), except for the relationship of otolith length against total weight (female), and displayed a high coefficient of determinations ranging between 0.75 and 0.99.
The linear function and non-linear functions provided the best fit for 62.5% and 37.5%, respectively. Analyzing the morphometric relationships, it is concluded that otolith length and otolith weight are good indicators of the total length and weight of tubenose goby. These data will help researchers studying food habits of top predators to determine the size and weight of prey fish from length and/or weight of recovered otoliths.