The Morphometric Examination of Head Area of Black Headed Gulls (Larus Ridibundus) from Marmara Region

Year 2020, Volume: 39 Issue: 1, 49 - 53, 29.07.2020

Ozan Gündemir , Gülsün Pazvant Nazan Gezer İnce

https://doi.org/10.30782/jrvm.634404

Cited By: 2

Abstract

The Black-headed gull (Larus ridibundus), a gull species commonly
seen on shores of Küçükçekmece lake located in Marmara Region, does not exhibit
sexual dimorphism as it has monomorphic feather traits like the other gull
species.  In order to perform sex discrimination
in gulls, the effective discriminant function analysis (DFA) method is used for
the measurements based on the external morphology and determining the variables
discriminating the two sex groups. The head morphological measurements and the
body weights of 28 adult Black-headed gulls were obtained. One discriminant
function was determined based on the results. 
The accuracy rate in two sexes was determined to be 82.1% (85.7% female,
78.6% male) using the formula we obtained as a result of the discriminant
function analysis in which the head length, determined to be more significant
compared to the other variables, was used. The aim of the study is to assess
the sexual dimorphism in population of Black-headed gull in Küçükçekmece Lake
and its surrounding located in Marmara Region and represent a reliable method
to make a sex discrimination along with discriminant analysis. 

Keywords

Avian anatomy, black headed gulls, head morphometry, marmara sea

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