TABLE 3.

Summary statistics for two linear mixed effects models testing the influences of diet and sex on (1) the change in body condition, and (2) plasma corticosterone concentrations before and after the experimental diet was started. Corticosterone values were log transformed for analysis. Diets included a “natural” diet that mimics what white ibis eat in the wild and an “anthropogenic” diet, which is higher in carbohydrates and lower in protein. Body condition was significantly higher in males at all sampling points (Males: Mean = 10.83, Females: Mean = 9.57), and increased between the pre‐ and post‐diet body condition measures (pre‐diet mean: 10.02, post diet mean: 10.77). Plasma corticosterone concentrations also increased significantly between pre and post‐diet measures (pre‐diet: 4.20 ng/ml, post‐diet: 11.92 ng/ml)

Parameter (df)	Body condition					Plasma corticosterone
	F	p	Effect size	Lower 95%	Upper 95%	F	p	Effect size	Lower 95%	Upper 95%
Diet	0.16	.69	0.003	−0.06	0.07	0.01	.94	0.14	−3.46	3.74
Time	18.60	<.01	0.002	−0.02	0.02	7.89	.01	−4.86	−8.51	−1.21
Sex	6.90	<.02	0.01	−0.05	0.08	0.01	.93	0.15	−3.45	−3.75
Diet × time	2.52	.13	0.03	0.01	0.04	0.01	.95	0.10	−3.55	3.75
Diet × sex	0.33	.57	−0.003	−0.07	0.06	0.86	.37	1.57	−2.02	5.17
Sex × time	0.13	.72	−0.002	−0.02	0.02	0.42	.52	1.12	−2.53	4.78