This is due to the California Department of Fish and Wildlife listing all species of horned lizards as "specially protected". This means they cannot be captured, possessed, or sold without a permit.
The reason for this protection is that horned lizard populations have been declining due to habitat loss, introduced predators, and pesticide use.
If you are interested in learning more about horned lizards, you can visit the California Department of Fish and Wildlife website: [https://wildlife.ca.gov/](https://wildlife.ca.gov/)