Among socially monogamous species of birds, biparental care of young is common. However, the relative contributions of males and females in caring for young vary among species, with the contributions of males being most variable. During the nestling period, factors potentially influencing the contributions of males include certainty of paternity and nest predation rates. The provisioning rates of both males and females can be influenced by brood size and nestling age. Additional study is needed to better understand the relative importance of these various factors on the provisioning strategies of songbirds. Thus, the objective of my study was to examine the provisioning behavior of male and female Grasshopper Sparrows (Ammodramus savannarum), a socially and genetically monogamous songbird that nests in grassland habitats with high rates of nest predation. My study was conducted from 1 May-8 August 2002 and 30 April-29 August 2003 in Madison County, Kentucky. I located and videotaped the nests of 15 pairs of Grasshopper Sparrows, including one nest each for 11 pairs and two nests for four pairs. Tapes were subsequently reviewed and, for each nest visit, I noted the identity of the visiting adult and, when possible, identified prey items. Anaylsis revealed no difference in the provisioning rates of male and female Grasshopper Sparrows (P = 0.13), with mean provisioning rates of 2.16 ± 0.16 (SE) visits per hour for females and 1.86 ± 0.14 visits per hour for males. The provisioning rates of adult Grasshopper Sparrows did vary with nestling age (P = 0.01), with rates lower for 1-4 day old nestlings, increasing through day 6 post-hatching, then declining for 7-10 day old nestlings. Provisioning rates of Grasshopper Sparrows also varied with number of nestlings (P = 0.026), with rates higher for broods of five than for broods of three or four. For prey that I could identify (N = 960), most were grasshoppers (Orthoptera, Acrididae; N = 654, or 68.1%), followed by insect larvae (N = 217, or 22.6%), and crickets (Orthoptera, Gryllidae; N = 54, or 5.6% ). Because of their high chitin content, grasshoppers potentially provide nestlings with less energy per unit mass than other prey items. However, adult Grasshopper Sparrows minimize chitin content by removing the parts, such as legs, that contain the most chitin, and by feeding their nestlings medium-sized grasshoppers that have less chitin per unit than smaller grasshoppers. In contrast to many other species of songbirds where females provision nestlings at higher rates than males, I found that male and female Grasshopper Sparrows provisioned nestlings at similar rates. Factors potentially contributing to the relatively high provisioning rates of male Grasshopper Sparrows include confidence in their paternity and high rates of nest predation, with male provisioning likely important for insuring rapid growth of nestlings, earlier fledging, and a reduced risk of nest predation. Provisioning by males is also beneficial for pairs with larger broods, with male contributions helping to insure that nestlings are fed at comparable rates regardless of brood size. Such compensation may enhance their reproductive success because mass at fledging is an important predictor of survival for young birds. Male and female Grasshopper Sparrows in my study reduced provisioning rates and amount of biomass delivered to nestlings during the days just before fledging, with this reduction possibly inducing young to fledge. Such behavior may be a response to high rates of nest predation.