In the Gulf of California, Bahía Santa Maria (BSM) is a wetland of high ecological and economic importance. It is an important congregation site for shorebirds, ducks, and seabirds and is subject to increasing anthropogenic pressure from fishing and adjacent agriculture activities. Although BSM is designated as a priority wetland under a several conservation schemes, a comprehensive monitoring program to better understand the state of the ecosystem (important for administration and resource management) has never been undertaken. Seabirds are efficient indicators of ecosystem health and monitoring their populations and reproductive success, as well as changes in their feeding patterns, can help detect changes in the quality of the ecosystems seabirds are using. This project focuses on evaluating population size and determining diet, reproductive success, and habitat characteristics of breeding seabirds in BSM. Resulting information will serve as a baseline for monitoring changes in the environment in BSM.