CADIC 02618
CENTRO AUSTRAL DE INVESTIGACIONES CIENTIFICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Investigating determinants of egg size and composition in the Chilean Swallow (Tachycineta meyeni): insights from non-destructive photographic techniques
Autor/es:
MITCH WALTERS; MARCELA LILJESTHROM; CAREN COOPER; DAVID W. WINKLER
Lugar:
Geneva, NY, EEUU
Reunión:
Congreso; Wilson Ornithological Society Annual Meeting; 2010
Resumen:
<!--
/* Font Definitions */
@font-face
{font-family:Calibri;
mso-font-alt:"Century Gothic";
mso-font-charset:0;
mso-generic-font-family:swiss;
mso-font-pitch:variable;
mso-font-signature:-1610611985 1073750139 0 0 159 0;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{mso-style-parent:"";
margin-top:0in;
margin-right:0in;
margin-bottom:10.0pt;
margin-left:0in;
line-height:115%;
mso-pagination:widow-orphan;
font-size:11.0pt;
font-family:Calibri;
mso-fareast-font-family:Calibri;
mso-bidi-font-family:"Times New Roman";}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.25in 1.0in 1.25in;
mso-header-margin:.5in;
mso-footer-margin:.5in;
mso-paper-source:0;}
div.Section1
{page:Section1;}
-->
Variation in female and environmental characteristics can
lead to variation in egg composition for a variety of bird species. We investigated the relationship between
female attributes and egg/yolk size in
Chilean Swallows (Tachycineta meyeni)
breeding in Ushuaia, Argentina. We examined
whether egg/yolk size varied with female attributes, varied with egg-laying
sequence, and/or showed any seasonal trends.
We carried out our investigations using egg measurements collected in
the field as well as egg and yolk measurements extracted from digital
photographs taken in the field with a standardized egg candler, the
ovolux. If egg dimensions extracted from
photographs were comparable to field measures, then the ovolux could reduce egg
handling and breakage in the field. Based
photo-derived data, both egg and yolk dimensions decreased as the season
progressed, though we could not detect these changes based on field
measurements. The nature of the correspondence between field values and digital
image values suggest some refinements to the ovolux methods may be needed.
