Comparative egg attendance patterns of incubating polar petrels

Table 3 Egg turning patterns (mean ± SD) of snow and Cape petrels breeding at Dumont d’Urville Station, Antarctica

Species	N	Egg turning rate (turns h⁻¹)	Angle change per turn (°)	Time between turns (min)	Max time between turns (min)
Snow petrel	15^a	1.31 ± 0.33	43.1 ± 43.2	36.0 ± 11.0	290 ± 206
(min, max)	15^a	(0.82, 1.81)	(10, 180)	(17.1, 53.1)	(62, 961)
Cape petrel	14^b	1.38 ± 0.39	48.6 ± 43.7	42.5 ± 13.7	268 ± 119
(min, max)	14^b	(0.76, 2.03)	(10, 180)	(26.1, 74.9)	(146, 554)

Turning patterns were monitored using artificial eggs with data loggers recording changes in egg orientation at intervals of 1 Hz. N is the number of nests that were evaluated for each parameter. Egg turning and angle changes per turn were based on the combined angular changes (i.e., roll, pitch, and yaw) in egg attitude [26]. Statistical comparisons revealed no significant difference between species for each parameter, except angle change per turn (see “Results”)
^aTwo of 17 loggers had faulty accelerometers, but accurate temperature thermistors
^bOne of 15 loggers had a faulty accelerometer, but accurate temperature thermistor

ISSN: 2050-3385