Limited information about nutrition exists on American White Pelicans (Pelecanus erythrorhynchos) from hatching to fledging. To detail immunity, metabolism and nutrition of juvenile American White Pelicans, during 22-23 July 2011, 103 samples of regurgitate matter were collected at five Chase Lake, North Dakota, USA, and three Bitter Lake, South Dakota, USA, sub-colonies. Regurgitate sample nutrient content was significantly different for organic matter (P = 0.012), crude protein (P = 0.001), neutral detergent fiber (P = 0.014), acid detergent fiber (P = 0.005) and energy (P = 0.034) between North (n = 5) and South (n = 3) Dakota American White Pelican colonies. Average concentrations of immunoglobulins Y (2.74 ± 1.85 ng/mL) and A (9.04 ± 9.41 ng/mL) demonstrated passive transfer of immunity in regurgitate. To enhance information on growth and morphology in hand-reared American White Pelicans (n = 8), a 9-week captive trial was also conducted raising chicks from hatching to fledging. Predictive models were created to describe chick growth for intake, body weight, culmen length and tarsus length. Data collected during this study enhances both American White Pelican general ecology and conservation with implications for both captive and wild bird management.