Incubation strategies of the Black-necked Crane (Grus nigricollis) in relation to ambient temperature and time of day

Table 1 Results of general linear mixed model examining factors that influence nest attendance, recess frequency, on-bout duration and egg turning frequency of female Black-necked Cranes between 06:30 and 20:30 h at the Yanchiwan National Nature Reserve, Gansu, China

Fixed-effect variables	Nest attendance			Recess frequency			On-bout duration			Egg turning frequency
Fixed-effect variables	β ± SE	t	p	β ± SE	t	P	β ± SE	t	p	β ± SE	t	p
Year	0.36 ± 0.03	12.39	<0.001	0.24 ± 0.09	2.58	0.01	0.61 ± 0.07	8.45	<0.001	0.91 ± 0.24	3.86	<0.001
Date	0.06 ± 0.005	12.03	<0.001	0.15 ± 0.03	5.90	<0.001	0.06 ± 0.01	4.82	<0.001	0.19 ± 0.04	4.66	<0.001
Day of incubation	−0.05 ± 0.005	−10.35	<0.001	−0.16 ± 0.03	−5.66	<0.001	−0.05 ± 0.01	−3.75	<0.001	−0.19 ± 0.04	−4.30	<0.001
Time of day	0.04 ± 0.006	6.68	<0.001	0.11 ± 0.04	3.28	0.001	0.05 ± 0.01	3.64	<0.001	0.05 ± 0.05	1.10	0.274
Temperature²	−0.000 ± 0.000	−0.33	0.741	−0.001 ± 0.001	−2.16	0.031	−0.000 ± 0.000	1.13	0.260	−0.002 ± 0.001	−1.95	0.051
Temperature	−0.001 ± 0.003	−0.22	0.828	−0.04 ± 0.02	2.41	0.016	−0.02 ± 0.009	−1.76	0.078	−0.07 ± 0.03	2.45	0.015
Male	−0.63 ± 0.05	−13.30	<0.001	−0.19 ± 0.09	2.06	0.040	−0.55 ± 0.07	−8.00	<0.001	−0.10 ± 0.08	−1.19	0.234
Male × time of day	−0.05 ± 0.001	−4.84	<0.001	−0.08 ± 0.02	−3.74	<0.001	−0.03 ± 0.02	−1.95	0.052	−0.04 ± 0.02	−1.99	0.047

ISSN: 2053-7166