California Reenacts State Law Protections for Migratory Birds

Key Takeaways

• There has been substantial back-and-forth and uncertainty in recent years over whether the federal Migratory Bird Treaty Act prohibits only the intentional take of covered birds, or whether it also protects against incidental take.
• Assembly Bill 454 reaffirms that, regardless of the fluctuating interpretations under federal law, state law protects against both the intentional and incidental take of migratory birds.

Governor Gavin Newsom signed Assembly Bill 454 into law, reenacting the California Migratory Bird Protection Act as codified in Section 3513 of the Fish and Game Code, on October 6, 2025. This state law prohibits the unauthorized “take” of any bird species that is covered by the federal Migratory Bird Treaty Act (MBTA) of 1918. This state prohibition broadly applies to both the intentional and incidental take of covered birds. An intentional take occurs where the take is the intended purpose of the activity at issue, such as purposefully hunting or capturing a covered bird. By contrast, an incidental take occurs when the take is not the intended purpose of the activity at issue, such as land clearing for a development project that inadvertently or unknowingly results in the death of a covered bird.

The federal MBTA covers more than 1,000 species of birds, many of which are common and abundant. For a number of years, there has been a split among the federal courts as to whether the statute protects against incidental take. In January 2017, at the end of the Obama administration, the U.S. Department of the Interior (the Department) published an opinion (M-37041) stating that the MTBA’s protections apply equally to both the intentional and incidental take of migratory birds. But in December 2017, after the change in administration, the Department published a new opinion (M-37050) stating that the statute applies only to intentional take. 

In response to this change in interpretation in federal law, in 2019, California amended Section 3513 of the Fish and Game Code, the state law that implements the federal MBTA and makes its protections enforceable by the California Department of Fish and Wildlife. This 2019 amendment locked in place the federal MBTA protections that existed before the interpretive change under federal law, thus providing state law protection against both incidental and intentional take. But the amendment to Section 3513 became inoperative by its own terms in January 2025.

Since the 2019 state law amendment, the federal government’s position on the reach of the MBTA has continued to vacillate. At the beginning of the Biden administration, in March 2021, the Department reversed course again, issuing an opinion (M-37065) that reaffirmed that the MBTA’s protections fully applied to both intentional and incidental take. But in April 2025, the Department withdrew its 2021 opinion and reinstated its prior December 2017 opinion—and, thus, the position that the MBTA only prohibits intentional take (M-37085).

In response to this most recent rollback of federal protections, the newly enacted AB 454 locks in place—indefinitely—the federal MBTA protections that existed before January 1, 2025. As a result, the California Fish and Game Code now provides permanent protection against both the intentional and incidental take of migratory birds, regardless of the fluctuations under federal law. Landowners and developers in California therefore need to continue to be aware of how their activities might unwittingly result in an incidental take of migratory birds.