Time to begin first feeding bouts (hours relative to sunrise).

<p>Boxplots indicate the median and the interquartile range (IQR); whiskers indicate the extreme values unless there are data points more than 1.5*IQR below the lower quartile or more than 1.5*IQR above the upper quartile, in which case the whiskers stop at the first data points within those boundaries and open circles indicate more extreme points. n = number of observations.</p>