Mean prey mass (weight (g) ±SE) delivered during 30 min periods in the Czech (filled squares) and the Finnish population (open squares) against the sun angle in relation to the horizon (in degrees, 0 = sunrise/sunset, twl. = twilight).
<p>Mean prey mass (weight (g) ±SE) delivered during 30 min periods in the Czech (filled squares) and the Finnish population (open squares) against the sun angle in relation to the horizon (in degrees, 0 = sunrise/sunset, twl. = twilight).</p
