The growth of Thick-billed Murre chicks at colonies in Hudson Strait: inter- and intra-colony variation

Comparison of growth rates and fledging weights recorded for Thick-billed Murre chicks (Uria lomvia) by previous investigators shows that these parameters vary widely between studies. We measured growth rates and fledging weights at four colonies in the Hudson Strait area to examine the magnitude of variation both within and among colonies. Significant variations among years and among different areas of a single colony were detected but found to be less important than colony-specific factors in determining overall variation. A negative correlation between colony size and chick fledging weights suggests that colony size may be an important determinant of intercolony differences.