Bank swallows (Riparia riparia) are a colonial species of swallow that build nests by burrowing into eroding banks associated with streams, rivers, coastal bluffs, and lakeshores. Their populations have declined worldwide, primarily due to bank stabilization activities. Declines observed on the Sacramento River in the 1970s and 80s prompted a statewide survey in 1987 and led to the listing of bank swallows as state-threatened in 1989. In 2021, the California Department of Fish and Wildlife (CDFW) launched an effort to attain updated information about the current status and distribution of bank swallows by repeating the statewide survey. With the help of approximately 15 staff and 55 volunteers, CDFW surveyed 2,166 miles of habitat in 2021 and 184 miles in 2022. One hundred and sixty active bank swallow colonies and 72 inactive colonies were located during the survey. Of the 160 active colonies, 106 occurred in areas that were surveyed in 1987. The number of colonies declined from 126 in 1987 to 106 in 2021, and the number of burrows declined from 45,045 in 1987 to 31,829 in 2021. The decline of California’s bank swallow population highlights the need for continued habitat conservation, future surveys, and further investigation into the decline.