California Gulls successfully colonized the Salton Sea in 1997 with 22 nesting pairs near Obsidian Butte, extending their breeding range 650 km into one of the world’s hottest environments. Although the colony site is often subjected to seasonal flooding, the number of nesting pairs has increased to at least 40 in 1999. One or two pairs of Laughing Gulls continue to nest sporadically, although unsuccessfully; a nesting attempt in 1994 extended their range 50 km north into Riverside County.