California’s 652 bison records draw one of the strangest maps in this atlas. Nearly all of them, 594, sit in Los Angeles County, with a small scatter in San Diego and San Luis Obispo counties, not because the South Coast is bison country but because of a single island herd with a Hollywood origin story.
A film-shoot herd that never left
In 1924, fourteen bison were hauled to Santa Catalina Island, part of Los Angeles County, for the filming of a western and were simply left behind when production wrapped. The herd took hold on the island’s grass and chaparral hills, grew into the hundreds, and is still there, actively managed so its numbers stay in balance with the island’s plants. Los Angeles County’s towering count is that herd, documented again and again by island visitors.
A grazer on its own terms
A bison is built for open grassland: cows run to half a ton, bulls near a full ton, and both are far faster and more agile than their bulk suggests. Records appear in every month, cresting in April, when the spring calving season puts red calves on the ground. The mainland scatter reflects ranch and paddock animals rather than any wild movement, and none of these animals, island or mainland, should ever be approached.
Status in California
The overlay treats the bison as native to its mapped California range, and USGS NAS does not list it as nonindigenous in the state, but no wild, free-ranging population exists in California today. The Catalina herd is introduced and managed, and the IUCN lists the species globally as Near Threatened.
