White Sturgeon (Acipenser transmontanus) are an anadromous species of fish that reside primarily in the San Francisco Bay Delta (SF Bay) and migrate as adults into the major rivers of the Central Valley to spawn. Most spawning occurs in the Sacramento River between Verona and Colusa (Schaffter 1997), with a lesser amount of spawning on the lower San Joaquin River (Jackson et al. 2015). Some additional spawning may occur in tributaries such as the Feather, Bear, and Yuba rivers. White Sturgeon are long lived, potentially in excess of 100 years, with most reaching maturity by approximately 19 years, spawning every two to five years once mature (Chapman et al. 1996; Hildebrand et al. 2016). Successful recruitment to the adult population is uncommon, occurring approximately every six to seven years, highly correlated with above normal water years as measured by high mean daily Delta outflow (CDFW 2023; Fish 2010). The abundance of legal-sized White Sturgeon has declined considerably since the 1980s, when abundance was estimated to be approximately 175,000 fish (CDFW 2023; Danos et al. 2019). In 2015, the Department estimated abundance at about 48,000 fish (Danos et al. 2019), and the most recent estimate was about 33,000 fish (CDFW 2023).
At present, recreational anglers can keep one White Sturgeon per day, and a combined total of three per year, between 40 and 60 inches (in.) fork length, meaning the measurement of the fish from the front of its head to the fork in its tail. The season is open year-round, with some limited regional and/or seasonal closures. Fishing pressure for White Sturgeon has remained stable at roughly 40,000 to 45,000 anglers per year since 2013 when fees were first charged for the Sturgeon Fishing Report Card (Card). Based on Card returns, the number of fish harvested by anglers has remained relatively stable. The number of fish caught and released, however, has declined precipitously, indicating that fewer fish overall are being caught. According to Card data, in 2021, anglers kept 46% of landed fish (Hause et al. 2021). The majority of anglers that harvest
fish keep only one a year (75%), with only about 5% of anglers that harvest (1% of Card-holders) keeping the full three-fish limit. Exploitation rate of White Sturgeon is estimated to be very high, ranging from 8 to 29.6% between 2007 and 2015 (Blackburn et al. 2019). It is suggested that the highest exploitation rate that a White Sturgeon population can sustain is approximately 5 to 10% (Beamesderfer and Farr 1997). For comparison, Washington and Oregon use less than 4% as a target for management in areas that permit harvest.
During July and August 2022, the San Francisco Bay region experienced a major Harmful Algal Bloom (HAB) of Heterosigma akashiwo that resulted in significant mortality of fishes, including sturgeon. The Department recorded over 850 sturgeon carcasses, the majority legal-sized or larger and within the age range of the core spawning population (CDFW 2023). The number of carcasses observed during the HAB was 62% of the number harvested by anglers in 2022. Based on carcass studies and fish kills of other species of sturgeon, it is thought that only a small percentage of the fish killed floated long enough to be detected (Fox et al. 2020). While the absolute magnitude of the HAB’s impact on the White Sturgeon population is unknown, it is thought to be quite significant. In addition, in July and August of 2023, a HAB of the same species was detected in San Francisco Bay and at least 15 White Sturgeon carcasses were reported, though the total impacts are unknown.
The fish kill resulting from the HAB has exacerbated what the Department believes to be an already unsustainable level of fishery exploitation of White Sturgeon into a crisis situation. To protect the surviving population of White Sturgeon and maintain a recreational fishery into the future, immediate steps are necessary to reduce angler associated harvest of adult White Sturgeon and to minimize harassment and handling on the spawning grounds so that these adults can spawn successfully, and new individuals can recruit to the population. The Department is recommending harvest of White Sturgeon within the recreational fishery be sharply reduced until new regulations can be developed that will limit exploitation to sustainable rates based on monitoring. Because the overall impacts of the HAB on the population is unknown, but considered to be significant to the adult spawning population, the reduction in harvest will increase the ability for adult survival and spawning opportunity. The Department believes this is a necessary interim change to the regulation while updated management measures that will allow future populations to persist are being developed.
Under the proposed regulation, take will still be permitted to anglers that purchase a Sturgeon Report Card but harvest will be limited by 1) reduction of the legal slot limit, 2) reduction of the annual bag limit, 3) adding a vessel limit of two fish per day, and 4) protecting critical migrating and spawning behavior via a seasonal and geographic closure of river habitat. Take via catch and release angling will be permitted after anglers reach their annual harvest limit to promote recreational angling opportunities. White Sturgeon are known to handle catch and release fishing with minimal adverse impacts except during spawning season when additional stress of catch can cause fish to abort spawning activities.
Sturgeon Report Cards will continue to be required. Report Cards are an important tool for the Department to gather data on the existing sturgeon population. Length information on all sturgeon caught provides the Department with data on the size structure of the population. It also provides
information on the number of legal-sized fish that are voluntarily released (during a harvest fishery), which helps us better understand angler attitudes/behavior. The Department will use these data to track cohorts as they grow, which can inform future harvest regulations. This demographic information is integral to a management strategy for White Sturgeon in California.
Proposed Emergency Regulations
In response to this emergency situation, this proposed regulatory action amends sections 5.79, 5.80, 27.90, and 29.72, Title 14, CCR, which describe report card and tagging requirements, and seasons and bag limits for White Sturgeon sport fishing in inland waters.
Subsection 5.79, White Sturgeon Report Card and Tagging Requirements for Inland Waters
The emergency regulations will amend White Sturgeon report card and tagging requirements for inland waters in the following subsections:
All subsections: White Sturgeon has been capitalized for consistency throughout the regulation.
Subsection (b): Edit text to reflect that report cards will come with only one tag rather than three. Add subsections (7) and (8) to clarify when anglers can continue to fish catch and release after harvesting a fish. Anglers will not be permitted to fish catch and release the same day they harvest a fish in order to prevent 1) take over the daily possession limit and 2) “high grading” (holding a fish in captivity while continuing to fish in the hopes of catching a larger individual).
Subsection (c)(1): Add a requirement for anglers to report length of caught fish. This is necessary to provide more data availability on the nature of size to inform future management options related to age.
Subsection (c)(2): Remove the current language that tells anglers if all lines on the card are filled, any additional sturgeon caught and released do not need to be recorded, and replace with language guiding anglers to report additional sturgeon caught and released on the back of the card. This is necessary in order to track fishing pressure and success. It is valuable to track all fish caught by anglers and this should not be restricted simply by the size of the printed card. This type of data allows the Department to form a better understanding of the fishery as we plan long-term regulations for the fishery.
The California Fish and Game Commission (Commission) enacted emergency regulations yesterday to reduce the harvest of white sturgeon in state waters. The new regulations will reduce the number of fish that can be kept to one per year, reduce the slot limit to 42-48 inches, cap the number of white sturgeon that can be possessed on a vessel at two per day and add seasonal closures to sturgeon fishing in key spawning areas. The new regulations are expected to go into effect in late October or early November following approval by the Office of Administrative Law.
The new regulations were enacted by the Commission following a joint recommendation by the California Department of Fish and Wildlife (CDFW) and angling groups. The emergency action was taken in response to long-term declines in adult white sturgeon populations as well as impacts of a harmful algal bloom (HAB) in the summer of 2022.
“It was a difficult decision to recommend restrictions to another fishery in California,” said CDFW Fisheries Branch Chief Jay Rowan. “The angling community representatives really stepped up by offering deep concessions to help reduce sturgeon harvest and showed, yet again, that they are committed to protecting this resource.”
There are two sturgeon species in California: green sturgeon and white sturgeon. Green sturgeon are listed as a threatened species under the Federal Endangered Species Act. White sturgeon are listed in California as a Species of Special Concern.
Sturgeon are one of the oldest fish in existence with fossil records dating back more than 200 million years. Individual white sturgeon can live about 100 years and don’t start spawning until approximately 14 to 19 years old. Scientists estimate that white sturgeon in the Central Valley only spawn successfully every six to seven years. White sturgeon abundance has declined significantly from approximately 200,000 harvestable fish in 1997 to around 33,000 (recent five-year average). Sturgeon fisheries in California have closed multiple times in the past due to overharvest.
“Like other long-lived fish that spawn infrequently, sturgeon are susceptible to population declines due to a variety of environmental stressors and overharvest,” said Rowan.
During the summer of 2022, a HAB in the San Francisco and San Pablo bays caused the death of tens of thousands of fish including at least 864 sturgeon. Most sturgeon experts believe there were likely thousands more sturgeon killed during the HAB which sank to the bottom of bay waters and were not counted.
Harvest will be reduced to one white sturgeon for 2023 and 2024. Catch and release fishing for white sturgeon will still be allowed with a valid sturgeon report card after one sturgeon is kept except for closures outlined in California Code of Regulations, title 14, sections 5.80(opens in new tab) and 27.95(opens in new tab). The slot limit was reduced to 42-48 inches, and a limit of two fish per vessel per day was added. Fishing for white sturgeon will also be closed seasonally upstream of the Highway 50 bridge on the Sacramento River and Interstate 5 bridge on the San Joaquin River from January 1 to May 31, 2024. This upstream area will re-open to catch and release fishing on June 1, 2024, once spawning season is over.
Sturgeon Report Cards purchased in the 2023 calendar year remain valid for the remainder of 2023. All reporting, tag and report card requirements remain in effect. Only one sturgeon harvest tag will be valid. Any remaining sturgeon harvest tags beyond one still in possession for the 2023 calendar year will be invalid for the remainder of 2023 once the new regulations take effect. Anglers that have already harvested one or more fish in 2023 will still be allowed to catch and release sturgeon for the remainder of 2023 with a valid Sturgeon Report Card. The changes to sturgeon harvest regulations may cause a delay in availability of 2024 sturgeon report cards and the single harvest tag. Report cards for 2024 will be available for sale as soon as possible after November 15, 2023 and before January 1, 2024. Sturgeon Report Card requirements will remain in effect for 2024.
CDFW is currently working on a white sturgeon regulation package to allow for limited harvest. The regulation package is scheduled to go through the Commission regulation setting process with a target effective date of January 2025.