Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023

Assessing colour variation of the common eider, Somateria mollissima, in the Faroe Islands and Iceland.

Höfundar / Authors: Elisabeth Knudsen1,2, Snæbjörn Pálsson1, Ellen Magnúsdóttir2, James A. Fletcher2, Árni Ásgeirsson2, Jóhannis Danielsen3, Sveinn Are Hanssen4, Jón Einar Jónsson2

Starfsvettvangur / Affiliations: 1. Institute of Life- and Environmental Sciences, University of Iceland, Sturlugata 7, 101 Reykjavík, Iceland (Email: elk26@hi.is) 2. University of Iceland, Snæfellsnes Research Center, Hafnargata 3, 340 Stykkisholmur, Iceland 3. Faroe Marina Research Institute, Nóatún 1, 100 Tórshavn, Faroe Islands 4 Norwegian Institute for Nature Research (NINA), Sognsveien 68, 9855 Osla, Norway

Kynnir / Presenter: Elisabeth Knudsen

The evolution of bird colouration has become a central matter in behavioural and evolutionary ecology and assessing the accurate colour is imperative. Female common eiders, Somateria mollissima, generally are greyish brown in colour with dark barring on the body but show individual variation from light grey to dark brown. The eiders in the Faroe Islands (S. m. faeroeensis) are usually described as dark while eiders from Iceland (S. m. borealis) are described as light/grey. We use a Konica Minolta Chromameter CR-400/410 to assess the colour in numerical data of female common eiders in Iceland and the Faroe Islands. The Chroma Meter measures Hue, Light and Chrome. We measured five body parts: Wing, back, chest, head, and face. This gives us a total of 15 values per bird measured. Of the 43 birds measured in the Faroe Islands, 57.5% were yellow/red (Y/R), while only 3.3% were Y/R of the 124 birds measured in Iceland. For comparison, we measured museum skins from four king eiders, Somateria spectabilis, and interestingly they were 75% Y/R. We describe the colour variation within and among the two subspecies, both for individual traits and in combination per different individuals.