In western North America, seabird colony catalogs and monitoring programs exist for all of Alaska, Washington, Oregon, California, and Hawaii. The next logical step is Mexico. A seabird colony catalog is essentially a list of all known seabird colonies in a given region, with best available information on species composition and population sizes. It represents the state of knowledge of the distribution and abundance of breeding seabirds. A catalog of seabird breeding colonies is needed to evaluate potential marine IBAs in the Mexican portion of the California Current. This baseline data will be useful to support the designation of Marine Protected Areas around important nesting islands. In this framework, the objectives of this project are: 1) to create a catalog of breeding colonies located on the Pacific coast of the peninsula of Baja California; 2) to determine the Pacific seabird monitoring effort on in northwest México; and 3) to compile Pacific seabird monitoring data and enter this data to update the PSMDB.