Understanding new endangered fish listings in California
The federal listing of Longfin Smelt, and the proposed state listing of White Sturgeon, will require additional consideration when undertaking projects in California that could affect these two species.
Longfin Smelt (Spirinchus thaleichthys)
On July 30, 2024, the U.S. Fish and Wildlife Service (USFWS) published in the Federal Register a rule under the Endangered Species Act (ESA) that listed the San Francisco Bay-Delta distinct population segment (Bay-Delta DPS) of Longfin Smelt as endangered. This rule went into effect on August 29, 2024.
The approximately 4-inch Longfin Smelt typically lives for 2-3 years. The Bay-Delta DPS occupies the San Francisco Bay estuary and areas of the Pacific Ocean as far out as the Farallon Islands and along the California coast from approximately Half Moon Bay to the Russian River.
Figure 1. Range of the San Francisco Bay-Delta Distinct Population Segment of Longfin Smelt from US Fish and Wildlife Service
In the listing rule, the USFWS described threats facing the Bay-Delta DPS of Longfin Smelt as:
- Habitat alteration
- Changes to hydrology associated with reduced or altered freshwater flows
- Increased water temperatures
- Reduced food resource availability
- Predation
- Entrainment from freshwater diversion facilities
- Contaminants
Longfin Smelt has been listed as threatened under the California Endangered Species Act (CESA) since 2009, so many projects already take this species into account. However, in contrast to the federal ESA listing, the CESA listing is much broader and applies statewide to the species, including areas north of the range noted in the federal rule.
Recent research undertaken by ICF is one of several sources used by USFWS to inform their knowledge of the distribution of Longfin Smelt species in estuaries north of San Francisco Bay. In practical terms, project proponents with a site within the federally recognized range of the species (e.g., within San Francisco Bay) may need take authorization under both the ESA and CESA.
Federal take authorization can be obtained by submitting a biological assessment to the federal action agency (who will consult with USFWS) or by preparing a habitat conservation plan (if no federal nexus exists).
State take authorization may be obtained via an incidental take permit application submitted to the California Department of Fish and Wildlife (CDFW). If the project site is within California but outside the federally recognized range (e.g., within Humboldt Bay), only CESA permitting may be required. Within the federally recognized range, project proponents will need to consider differences between state and federal permitting requirements—such as the definition of “take”—and potential mitigation needs.
White Sturgeon (Acipenser transmontanus)
The California Fish and Game Commission also accepted for consideration a petition to list White Sturgeon as a candidate species for listing as threatened under the CESA on June 19, 2024. Under the CESA, candidate species are granted full protection during a 12-18 month review process, after which a final determination regarding listing will be made.
As described by the CDFW, White Sturgeon may be found in coastal waters from Mexico to Alaska. Although occasionally found in the ocean, the species primarily resides in large rivers and their associated estuaries, including California’s Sacramento-San Joaquin system and the San Francisco Bay estuary, which is the southernmost spawning population.
Figure 2. Current Distribution of White Sturgeon from California Department of Fish and Wildlife
White Sturgeon are the largest freshwater fish found in North America. Although there are historical records of fish up to 20 feet long, it is now rare to encounter fish larger than 6.5 feet in Californian waters. The oldest fish on record was 103 years old at the time of capture, but most fish in the Bay-Delta are now believed to be less than 20 years old, with age at first reproduction of approximately 10-19 years old (males mature earlier and at a smaller size than females).
The CDFW summarized this species' threats as including:
- Habitat loss and climate change that might degrade or destroy the limited spawning habitat in the Sacramento River.
- Entrainment of early life stages into water diversions.
- Contaminants from pollution and terrestrial runoff.
- Poaching and illegal fishing for meat and eggs.
- Recent harmful algal blooms in San Francisco Bay.
Final regulatory approval for the CESA listing candidate status was published on July 12, 2024. Within one year of that date, the CDFW will submit a report indicating whether listing is warranted. Recreational fishing for White Sturgeon was closed beginning July 13, 2024, but was re-opened under a special CESA exemption in August 2024 to catch-and-release fishing in some portions of the range between October 1 and December 31 only.
In anticipation of potential candidacy and eventual listing following the proposal for listing in November 2023, some project proponents submitting incidental take permit applications provided additional information to the CDFW regarding White Sturgeon effects (e.g., for the Delta Conveyance Project as prepared by ICF for the California Department of Water Resources).
Proposed projects with the potential to take White Sturgeon should include the species in their state incidental take permit applications until the listing review process is complete, and after that, if the species is listed.
Big picture
The listing of Longfin Smelt, and proposed listing of White Sturgeon, as endangered species highlights the need for project proponents to coordinate with environmental agencies, researchers, and other experts. If a project may impact either species, project proponents should identify strategies for compliance such as potential measures to avoid, minimize, and mitigate impacts.
