Monarch Butterfly Endangered Species Listing

By Rob Schell, WRA Senior Wildlife Biologist

How does a wildlife biologist keep themselves occupied during nine months of working from home? Well for one, I have been listing backyard species, as you do. Something that I insist that all my staff do for every project site they visit, is also something that I have neglected to do for my Bay Area bungalow on the eastern shore of San Francisco Bay. These small “discoveries” have kept me grounded and provided opportunities to connect with my colleagues and other bird-nerd friends. From the makeshift workspace at my kitchen table, I have caught myself looking out the window into our modest backyard many times, breaking up the monotony of workday. Highlighted finds from this year include a hermit thrush (Catharus guttatus), a western tanager (Piranga ludoviciana), and most recently a few migratory pine siskins (Spinus pinus). But there was one consistent visitor that I found myself more excited about than adding another species to my bird list.

A Decline in Familiar Visitors

With their large size, showy orange and black wings, Monarchs certainly are not inconspicuous. They are readily identifiable to even the most casual self-identified naturalist. However, until 2020, when pandemic-induced confinement allowed me to slow down and pay more attention to my immediate surrounds, I do not recall ever seeing them in the suburban neighborhoods of the Berkeley Hills in my 15-years living here. Monarchs were a species I learned about in elementary school. The archetype for learning about metamorphosis. As children, we reared caterpillars in styrofoam cups on milkweed (Asclepias spp.) common nearly everywhere, and seemingly scarcely seen today. Monarchs can still be found along north-south migratory corridors throughout much of low-lands of the United States, although in far fewer numbers than were seen 25 years ago. Populations east of the Rocky Mountains have declined by a staggering 85% since 1996, and the California population has fared worse. Counts performed in 2019 are a whopping 97% lower than in 1997.

Because of these declines, Monarchs were petitioned to be listed on the federal Endangered Species Act (ESA), administered by the U.S. Fish and Wildlife Service (USFWS), in 2014 which began a 5-year evaluation process to determine whether Monarchs could or would be listed as threatened or endangered. This process culminated recently on December 15th, 2020 when the USFWS determined that Monarchs are deserving of ESA protections, however other species have a more imminent need of federal resources, rendering a decision of “warranted, but precluded.”

This video clip was taken of a large wintering roost of Monarchs on The Nature Conservancy’s Jack and Laura Dangermond Preserve January 20, 2015.

What ‘Warranted, But Precluded’ Means for Monarchs

In this decision, the Monarch joins a list of more than 250 species in similar regulatory limbo. The USFWS currently considers 161 species “higher priority” than the Monarch Butterfly. Many factors go into this prioritization schema, including outstanding litigation, and other conflicting obligations. As a consolation, Monarchs will remain “Candidate Species” under the ESA and will be reevaluated or reprioritized on an annual basis until they are formally listed, or protection under the ESA is determined to be “not warranted.”

As candidate species, Monarchs receive no statutory protection under the ESA. However, in the absence of formal listing status, voluntary partnerships are already underway by states, tribes, Canada and Mexico, local communities, and conservation organizations that are taking actions to unwind some of the ecological and man-made changes that have resulted in the species’ precipitous declines. In certain cases, these voluntary actions have resulted in strong enough conservation and restoration outcomes where species numbers have stabilized and even rebounded without ever receiving formal listing status.

In certain cases, federal protections can make recovery actions more difficult to implement through complex, lengthy and expensive permitting and mitigation processes. And in other cases, draw considerable blowback from partners that would be critical in eventual species recovery. A recent example is the March 31, 2020 decision to withdraw listing of the Bi-State distinct population segment (DPS) of greater sage-grouse (Centrocercus urophasianus), a decision made -in part- based on a broad and multifaceted response to undertake voluntary actions by stakeholders including landowners, land managers, state and local agencies, NGOs and other parties to proactively benefit the sage grouse and its habitat rather than seeing the bird listed under the ESA. Given the ethereal nature of the Monarch, where it can be both common and rare on temporal and spatial scales, an analogous solution could eventually take form.

Until such time as a final decision is made, the USFWS has developed a Nationwide Candidate Conservation Agreement on energy and transportation lands. Under this agreement more than 45 energy and transmission companies and state’s departments of transportation are voluntarily committing time and funding to carry out Monarch-friendly management practices on millions of acres and along linear transportation corridors. Like with the sage grouse, actions like this may preclude the need to list Monarchs at all or could aid in species recovery. This agreement also provides signatories with protections from additional, potentially burdensome, conservation measures in the event that Monarchs are eventually listed under the ESA.

An individual Monarch on Rob Schell’s backyard fig tree.

California Protections for the Monarch

At the state-level, CDFW recognizes Monarch as a “Special-status Invertebrate” and tracks its known communal wintering sites. As such, conservation measures are often applied to these sites within the context of both CEQA and local environmental review processes. In October 2015, the California legislature passed Assembly Bill 559, which brings renewed conservation attention to the monarch. While the legal status of the butterfly remains unchanged, the bill amends the California Fish and Game Code to allow CDFW to “…take feasible actions to conserve monarch butterflies and the unique habitats they depend upon for successful migration.” To this end, CDFW “shall use the best available science” to restore or revegetate both milkweed habitat and nectar plants, and wintering habitats, and also to increase the number of partnerships involving both public and private entities to promote monarch conservation.

While the California Fish and Game Commission have taken stronger steps recently to formally list four bumble bee species under the California Endangered Species Act (CESA) in June of 2019. However, a in a recent decision on November 13, 2020 by the Sacramento Superior Court in the case of Almond Alliance et al. v. California Fish and Game Commission ruled that insects are not fish. While that may sound obvious, State Fish and Game Code extends the definition of fish to include invertebrates. However, following a nearly four-decade long debate on this issue, and several failed attempts to amend Fish and Game Code specifically to include terrestrial invertebrates, the Court “[i]n context, the word ‘invertebrates’ as it appears in Section 45’s definition of ‘fish’ clearly denotes invertebrates connected to a marine habitat, not insects such as bumble bees.”

In the absence of rigorous federal or state protections, the plight of the Monarch continues, and unfortunately their numbers will likely continue to decline in the near-term. However, for my part, over the course of the pandemic, I have attempted to terraform my yard by removing the english ivy ground cover and other low value ornamental species, and attempting to cultivate a pollinator-friendly, native plant palette. Although my actions are unlikely to move the needle on Monarch conservation, the number of hummingbirds that frequent my yard, the increasingly long species list, and the 4-8 daily Monarch visitors over the last nine months have made me smile and are motivation enough to continue the effort. Whether my landlord agrees with my do-gooder yard renovations or not remains to be seen.