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Fecundity in ungulates is an important component of population dynamics, and itself can be driven by differences in the age and nutritional condition of females. As one element of a larger research project focused on moose (Alces alces) population dynamics and ecology, we examined nutritional condition, pregnancy rates, and litter sizes for moose in three Montana moose populations. During the winters of 2013–2015 we captured 100 female moose≥ 1 year old and assessed pregnancy status using assays of both serum (pregnancy specific protein B [PSPB]) and feces (fecal progesterone). After calibrating the relationship between these two assays, we subsequently monitored pregnancy with feces alone for additional winters following capture. Coincident with captures, animals were aged using tooth extraction and cementum analysis, nutritional condition was assessed using ultrasonography of rump fat …