Endangered Species Protections Proposed for Monarch Butterfly

On December 10, 2024, the U.S. Fish and Wildlife Service (USFWS) proposed to list the monarch butterfly (Danaus plexippus) as threatened under the federal Endangered Species Act (ESA). A proposed critical habitat designation and “4(d) rule” offering species-specific protective regulations were also put forth (collectively, the Proposed Rule). USFWS is seeking public comment on the Proposed Rule through March 12, 2025.

Monarch butterflies, easily recognized by their orange and black markings, annually migrate across a vast swath of North America as part of two distinct subpopulations. The eastern population is the largest and overwinters in the mountains of central Mexico, whereas the western population primarily overwinters in coastal California. According to USFWS, both populations have severely declined since the 1980s. Data asserted by various conservation groups suggests that the eastern migratory population has decreased by 80% and the western migratory population by more than 95%. Threats to the monarch include habitat loss, conversion and degradation, exposure to herbicides/insecticides, and the effects of climate change.

The Proposed Rule’s critical habitat designation covers the western monarch population’s overwintering sites in seven coastal California counties (Ventura, Santa Barbara, San Luis Obispo, Monterey, Santa Cruz, Alameda, and Marin). Notably, the ESA’s critical habitat restrictions only apply to projects with a federal “nexus,” via permitting, funding or approvals. Additionally, the proposed 4(d) rule provides exemptions from the ESA’s broader “take” prohibition, incentivizing the general public to proactively undertake conservation efforts without fear of unintentional violation of the ESA. Proposed exemptions include:

• • Activities that may maintain, enhance, remove, or establish milkweed and nectar plants within the breeding and migratory range
  • Implementation of comprehensive conservation plans
  • Maintenance or improvement of monarch overwintering habitat
  • Monarch mortality due to vehicle strikes
  • Small-scale collection, possession, captive-rearing, and release of monarchs
  • Scientific research and educational activities
  • Possession of dead monarchs
  • Sale of captively reared monarchs

The Proposed Rule has been long anticipated. Various conservation groups petitioned the USFWS in 2014 to list the monarch on the ESA. The USFWS deemed the petition scientifically supported to warrant additional review; however, it failed to make a final listing decision within the ESA’s requisite 12-month period. Litigation ensued, and USFWS was given until December 2020 to make a final listing decision. USFWS determined on December 17, 2020, that adding the monarch butterfly to the ESA was “warranted but precluded” by higher-priority listing actions, and the monarch has remained on the candidate waiting list since.

The Proposed Rule was published in the Federal Register on December 12, 2024, thereby formally kicking off the 90-day public review and comment period, which will close on March 12, 2025. The USFWS will then have 12 months to conduct a status review and determine whether to (1) publish a final listing rule, (2) withdraw its proposal, or (3) extend its proposal.

We will track the outcome of the Proposed Rule and provide subsequent legal updates as things continue to develop over the next year. Please reach out to Allen Matkins’ Natural Resources Team if you would like to learn more about the Proposed Rule’s details or public comment process.