National Marine Fisheries Service Research Articles

Gray whale (Eschrichtius robustus) post-mortem findings from December 2018 through 2021 during the Unusual Mortality Event in the Eastern North Pacific.

Beginning in December 2018, increased numbers of gray whale (Eschrichtius robustus) strandings were reported along the west coast of Mexico, the United States, and Canada, prompting declaration of a gray whale Unusual Mortality Event (UME) by the United States National Marine Fisheries Service. Although strandings declined in 2020 and 2021 from a peak in 2019, the UME is still ongoing as of fall 2023. Between 17 December 2018 and 31 December 2021, 503 animals stranded along the west coast of North America, with 226 strandings in Mexico, 71 in California, 12 in Oregon, 56 in Washington, 21 in British Columbia, and 117 in Alaska. These included 187 males, 167 females, and 149 whales of undetermined sex; and 193 adults, 194 subadults, 40 calves, 1 fetus, and 75 whales of undetermined age class. We report on 61 of the 503 carcasses (12%) that had external and internal gross necropsy and/or histopathology data: of these 61 whales, findings that contributed to death were identified in 33 (54%) whales. Sixteen of the 61 (26%) were severely emaciated. Gross lesions of blunt force trauma consistent with vessel strike were identified in 11 of the 61 animals (18%), only two of which were emaciated. Two whales (3%) were entangled at time of death, and one died from entrapment. Signs of killer whale (Orcinus orca) interaction were documented in 19 of the 61 animals; five were deemed from recent interactions and three (5%) likely contributed to mortality. A specific cause of death could not be identified in 28 of 61 whales (46%). Additionally, logistical challenges and the advanced state of decomposition of most examined carcasses precluded detection of potential infectious or toxic causes of morbidity or mortality. Up to 2016, the eastern North Pacific population of gray whale population had generally been increasing since the cessation of historic whaling and a prior UME in 1999-2000. However, recent abundance and calf production estimates have declined, a trend that overlaps the current UME. The relative contributions of carrying capacity, environmental change, prey shifts, and infectious, toxic, and other processes to the increased gray whale mortalities have not yet been resolved. Nevertheless, the marked temporal increase in strandings, including findings of malnutrition in some of the whales, along with low calf production, likely represent consequences of complex and dynamic ecological interactions in the ocean impacting the population.

NOAA fisheries research geared towards climate-ready living marine resource management in the northeast United States

Climate change can alter marine ecosystems through changes in ocean temperature, acidification, circulation, and productivity. Over the last decade, the United States northeast continental shelf (U.S. NES) has warmed faster than any other marine ecosystem in the country and is among the fastest warming regions of the global ocean. Many living marine resources in the U.S. NES ranging from recreational and commercial fish stocks to protected species have shifted their distribution in response to ocean warming. The National Oceanic and Atmospheric Administration’s National Marine Fisheries Service (NOAA Fisheries) is responsible for the assessment, protection, and sustainable use of the nation’s living marine resources. In the U.S. NES, NOAA Fisheries has made substantial progress on climate research related to fish, fisheries, and protected species. However, more research is needed to help inform tactical management decisions with the goal of climate-ready living marine resource management. This is a major challenge because the observed physical and biological changes are unprecedented, and the majority of marine species assessments and management decisions do not utilize environmental data. Here we review the research accomplishments and key needs for NOAA Fisheries in the U.S. NES in the context of climate change and living marine resource management. Key research needs and products are: 1) Infrastructure with continued and enhanced ocean surveys that includes cooperative research with the fishing industry and other NOAA line offices and partners; 2) Tracking and projecting change, and understanding mechanisms including state of the ecosystem reporting, improved regional ocean and ecosystem hindcasts, forecasts, and projections, and continued process-based laboratory and field studies, 3) climate-informed management, including stock assessments that account for climate where possible, translation of changing species distributions into spatial management, climate vulnerability assessment and scenario planning, ecosystem-based management, management strategy evaluations, and increased multidisciplinary science that includes economic and social indicators.

A deep learning approach for object detection of rockfish in challenging underwater environments

IntroductionPreserving the marine ecological environment and safeguarding marine species is a global priority. However, human overfishing has led to a drastic decline in fish species with longer growth cycles, disrupting the equilibrium of the marine ecosystem. To address this issue, researchers are turning to deep learning techniques and state-of-the-art underwater devices, such as underwater robots, to explore the aquatic environment and monitor the activities of endangered populations. This approach has emerged as a focal point of recent research in protecting the marine ecological environment. This study employs a deep learning-based object detection algorithm to identify fish species in complex underwater environments.MethodsThe algorithm is built upon the You Only Look Once version 7(YOLOv7) algorithm, with the addition of the attention mechanism Convolutional Block Attention Module (CBAM) in the network’s backbone. CBAM enhances the feature maps through the fusion of spatial attention and channel attention, ultimately improving the robustness and accuracy of the model’s inference by replacing the original loss function CIoU with SCYLLAIntersection over Union(SIoU). In this paper, the rockfish pictures in the dataset Label Fishes in the Wild published by the National Marine Fisheries Service are selected, and the underwater image enhancement model (UWCNN) is introduced to process the pictures.ResultThe experimental results show that the mean average precision (mAP) value of the improved model on the test set is 94.4%, which is 3.5% higher than the original YOLOv7 model, and the precision and recall rate are 99.1% and 99%, respectively. The detection performance of the algorithm in the field of complex underwater environment is improved.DiscussionThe underwater fish detection scheme proposed in this study holds significant practical value and significance in promoting the conservation of marine ecosystems and the protection of fish species.

Towards mapping the gaps in Alaska

In 2018, the General Bathymetric Chart of the Oceans (GEBCO) announced the Nippon Foundation-GEBCO Seabed 2030 Project to improve further the GEBCO map of the world’s oceans. The United States (U.S.) has responded with different initiatives to complete a map of its Exclusive Economic Zone (EEZ). With Alaska accounting for the greatest fraction of the U.S. EEZ, here we provide an analysis showing which portions of the National Oceanic and Atmospheric Administration’s, National Marine Fisheries Service, Alaska Fisheries Science Center (AFSC) bathymetry maps are supported by actual observations. Data support of raster cells ranged from 2.4 % to 43.4 % within six previously published AFSC bathymetry compilations, with high variability by depth and supporting hydrographic data type. This will guide new Alaska mapping efforts towards the gaps and away from remapping areas, increasing progress in fulfilling the goals of Seabed 2030 Project.

Offshore wind project-level monitoring in the Northeast U.S. continental shelf ecosystem: evaluating the potential to mitigate impacts to long-term scientific surveys

Offshore wind will generate much needed renewable energy in the U.S. and worldwide, but this industry will also affect other ocean uses. In the Northeast U.S. continental shelf (NES) ecosystem, these effects include the impact that wind development will have on the design and execution of long running scientific surveys conducted by National Marine Fisheries Service of the National Oceanic and Atmospheric Administration (NOAA Fisheries) which play a critical role in the provision of scientific information for stock assessment and advice for fisheries management. Recognizing these impacts, the federal government has established a Survey Mitigation Strategy that identifies a need to evaluate whether the information yielded from project-level monitoring studies conducted by wind developers might be suitable for integration with data from NOAA Fisheries surveys, thereby ameliorating the impacts to the surveys. To address this need, we compiled and tabulated information from all currently available project-level monitoring studies and compared elements of the design and methodology of each study with that of the comparable NOAA Fisheries survey. Based on this information, we evaluated their suitability for filling expected gaps in long term surveys, for addressing impacts at the population level, and for understanding interactions between fish stocks and habitat alterations. We found that project-level monitoring studies as currently designed for the NES ecosystem will not yield information that can mitigate impacts to NOAA Fisheries scientific survey time series from offshore wind development. We provide recommendations on how to enhance the ability of project-level monitoring studies to mitigate impacts to long term scientific surveys.

Science Priorities for Offshore Wind and Fisheries Research in the Northeast U.S. Continental Shelf Ecosystem: Perspectives from Scientists at the National Marine Fisheries Service

AbstractOffshore wind development (OWD) is set to expand rapidly in the United States as a component of the nation's effort to combat climate change. Offshore wind development in the United States is slated to begin in the Greater Atlantic region, where it is expected to interact with ocean ecology, human dimensions, fisheries data collections, and fisheries management. Understanding these interactions is key to ensuring the coexistence of offshore wind energy with sustainable fisheries and a healthy marine ecosystem. These anticipated interactions compelled the authors, all fisheries scientists or managers at National Oceanic and Atmospheric Administration (NOAA) Fisheries who are actively engaged in offshore wind science to identify scientific research priorities for OWD in the Northeast U.S. Continental Shelf ecosystem, specifically in support of NOAA Fisheries' role as the nation's leading steward of marine life. We extracted and analyzed OWD research needs from existing scientific documents and used this information as the basis to develop a list of priorities that align with five major OWD science themes that are of high interest to NOAA Fisheries. These NOAA Fisheries themes include supporting the regulatory process; mitigating the impacts to NOAA Fisheries' surveys; advancing science to understand interactions with NOAA Fisheries trust resources, the marine ecosystem, and fishing industries/communities; advancing the science of mitigation for NOAA Fisheries trust resources and fishing industries/communities; and advancing data management methods. The areas identified as research priorities will support the coexistence of offshore wind and sustainable fisheries and inform the development of NOAA Fisheries' science plan for offshore wind in the Northeast U.S. Continental Shelf ecosystem as well as cross‐sectoral science planning efforts at the regional, national, and international levels.

Timing of the gray whale southbound migration

The southbound migration of the eastern North Pacific stock of gray whales (Eschrichtius robustus) has been documented by the National Marine Fisheries Service most seasons since 1967 at or near Granite Canyon, in central California, and by the American Cetacean Society’s Los Angeles Chapter every season since 1985 at Point Vicente, southern California. This has provided a rare opportunity to examine cetacean migratory timing data over a relatively long time series. In 1998/99, anecdotal reports indicated a major change had occurred in the timing of the migration, which prompted this study to compare the observed timing relative to expected dates. Although no observers were at Granite Canyon in 1998/99, data collected from this site indicated that prior to 1980, annual median sighting dates ranged from 4-13 January (overall median = 8 January; CI = 1.3), but since then there has been a one-week (6.8 day; CI = 2.0) delay, with median dates now ranging from 12-18 January (overall median = 15 January; CI = 1.7). This delay in timing is better represented as a shift in dates than as a trend, and it occurred shortly after a major oceanographic regime shift in the North Pacific Ocean. The shift in whale sighting dates occurred equally in the onset of the migrations (when the first 10% of the whales passed a site), the median (50%) and end (when 90% of the whales passed). At Granite Canyon, there were no significant trends in these dates prior to 1980 or in dates following the shift. In mid-February (median = 15 February, CI = 1.9, at Point Vicente), few gray whales are still going south and some are already migrating north. Most of the migration (the period between the 10% and 90% sighting dates) occurs across a period of 34 days (CI = 2.0), but the entire southbound migration may take > 70 days to pass a location in any given year. It takes a whale approximately 54 days to migrate from the north central Bering Sea to the lagoons in Baja California (8,000km), but some whales may travel as far as 10,000km. Based on available observations and calculations using a travel rate of 147km/day, current median (peak) sighting dates of the southbound migration should be: 1 December in the north central Bering Sea (here considered the theoretical starting point for the migration); 12 December at Unimak Pass, Alaska; 18 December for Kodiak Island, Alaska; 5 January for Washington State; 7 January for Oregon; 15 January for central California; 18 January in southern California; and 24 January at the northern lagoons in Baja California (considered here to be the terminus of the migration). Although no observations were made at Granite Canyon in 1998/99, sightings made at Yaquina Head, Oregon (median sighting date = 7 January) and at Point Vicente (median = 20 January) indicate that the timing of that migration was consistent with previous years.

Marine mammal protection from impulsive noise

In this presentation we will look at the metrics used by the National Marine Fisheries Service (NMFS) for determining noise exposure levels for marine mammals and fish from the effects of underwater impulsive noise. A common source of impulsive underwater noise is pile driving associated with activities such as bridge or pier construction or the anchoring of offshore structures. A portable measurement system that allows in field measurement verification and also provides results quickly will also be presented.

A validated targeted assay for environmental DNA detections of the Atlantic wolffish (Anarhichas lupus)

The Atlantic wolffish (Anarhichas lupus) was assessed as a species of Special Concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) under the Canadian Species-At-Risk Act (SARA) in 2001, and by the National Marine Fisheries Service in USA in 2004. Monitoring of marine Species-At-Risk would rely ideally on non-destructive methods. However, most monitoring of marine fish at-risk rely on trawl surveys that are potentially destructive of the environment. Inferring a species presence using environmental DNA (eDNA) detections offers an attractive alternative for Species-At-Risk monitoring, because it is non-destructive, specific, and sensitive. We developed and optimized a real-time quantitative PCR probe-based (qPCR) detection protocol that targets the eDNA of Atlantic wolffish, A. lupus. The qPCR protocol was validated in silico, in vitro, and in situ. Species-specificity was assessed in vitro by testing against the two other species of Anarhichas present in the northwest Atlantic. We did not observe DNA amplification for either of these two species. The assay was highly sensitive, with a limit of detection (95% confidence level) of 1.5 DNA copies per qPCR reaction. In situ tests showed that A. lupus eDNA is detected from expected depth strata in areas of known wolffish abundance. This study provides a proof-of-concept experiment that offers a robust, targeted, and non destructive protocol for detection eDNA of the Atlantic wolffish.

Estimates of abundance of the eastern North Pacific stock of gray whales (Eschrichtius robustus) 1997-2002

The southbound migration of the eastern North Pacific stock of gray whales (Eschrichtius robustus) was documented by the National Marine Fisheries Service from 13 December 1997 to 24 February 1998, 13 December 2000 to 5 March 2001 and from 12 December 2001 to 5 March 2002. Research protocol was essentially identical to that used in previous surveys. This involved single observers independently searching for whales and recording data on effort and sighting time, location, count and direction-headed. In 1997/98, there were 2,346 pods (3,643 whales) counted during 435.0h of standard observational effort when visibility was recorded as fair to excellent. In 2000/01, a total of 1,694 pods (2,754 whales) were counted during 592.4h, and in 2001/02, there were 1,712 pods (2,800 whales) during 531.5h. The southbound migrations in 1997/98 and 2001/02 were normal, beginning in mid-December, centred on mid-January (mean dates=18 January 1998 and 15 January 2002 respectively) and ending by mid-February. However, in 2000/01 (mean date=25 January 2001) the migration was more protracted than any other migration observed in the past 25 years, with many whales still travelling south three weeks after the typical end date. Data analysis procedures were comparable to those used in previous years, with the exception of a new correction factor for nighttime travel rates. Abundance estimates were 29,758 whales in 1997/98 (CV=10.49%; 95% log-normal confidence interval=24,241 to 36,531), 19,448 in 2000/01 (CV=9.67%; 95% log-normal confidence interval=16,096 to 23,498) and 18,178 in 2001/02 (CV=9.79%; 95% log-normal confidence interval=15,010 to 22,015). The abundance in 1997/98 was the highest estimate made since this project began in 1967/68. It was followed by two much lower estimates – probably related to the high mortality rates observed in 1999 and 2000. This whale population appears to be approaching the carrying-capacity of its environment.

Trends in bottlenose dolphin (Tursiops truncatus) strandings in South Carolina, USA, 1997-2003: implications for the Southern North Carolina and South Carolina Management Units

Trends in marine mammal stranding rates over multiple years can provide useful information on life history parameters, seasonal and spatial distribution and both natural and human-induced mortality rates when compared with baseline data. Data of bottlenose dolphin (Tursiops truncatus) stranding rates in South Carolina, USA from 1997-2003 were analysed. The objectives of this study were to: (1) compare recent trends in strandings with baseline data (1992-1996) for South Carolina; (2) compare strandings between the Southern North Carolina Management Unit (SNCMU) and the South Carolina Management Unit (SCMU); (3) determine annual, seasonal and spatial trends in bottlenose dolphin strandings; (4) investigate seasonal reproductive trends; and (5) determine the extent to which humans may affect stranding rates (human interactions). Bottlenose dolphins stranded in South Carolina are assumed to be from at least two of the seven management units recognised by the National Marine Fisheries Service in the Western North Atlantic: the SNCMU and the SCMU. During the study period, 302 bottlenose dolphin strandings were reported in South Carolina and stranding counts were analysed using a Generalised Linear Model. Results showed that there were significantly more bottlenose dolphin strandings in the spring and autumn as compared with summer and winter. The effect of season was highly significant for the number of neonate strandings, suggesting a bimodal reproductive cycle in spring and autumn for the study area. A significant increase in the number of strandings of all age classes was found in the autumn for the northern portion of the State (SNCMU), supporting the assumption that bottlenose dolphins from the north migrate into South Carolina waters during this time of year. Rope entanglements was the most common source of human interaction, with the crab pot fishery the most prevalent source of fishery mortality in South Carolina. This study demonstrates the usefulness of a long-term stranding database by increasing knowledge of temporal and spatial patterns and for monitoring neonate and human-induced mortality.

Chasing inter-species communication: what marine mammals are telling us about our oceans

Abstract I describe my path through a series of opportunities that provided stepping stones from childhood years in the landlocked US Midwest to a 45-year-long career focused on cetacean behaviour and ecology. My early interest in the ocean and dolphins led me to switch from majoring in journalism to biology during my undergraduate years. While pursuing a master’s degree focused on bioacoustics, I was employed as a contract scientist with the US Navy’s marine mammal laboratory. During 20 years there, my work ranged from dolphin calling behaviour to marine mammal distribution in Alaskan waters, culminating in a Ph.D. dissertation on cetacean habitats in the Alaskan Arctic. Subsequently, I enjoyed a 20-year career with the US NOAA National Marine Fisheries Service. There, I developed and advanced the idea that marine mammals can act as sentinels of ocean variability. To interpret the messages that marine mammals convey about the ocean, we must broaden science discourse to include Indigenous Knowledge and lessons from the experiences of people whose livelihoods depend on the sea. My advice to students and young professionals is to follow your passion while seeking the perspectives of colleagues from a variety of disciplines and people from all cultures and backgrounds. Coupled with a healthy dose of luck, this approach worked for me.

In Memoriam: William T. Hogarth

In Memoriam: William T. Hogarth

A characterisation of common bottlenose dolphin (Tursiops truncatus) interactions with the commercial shrimp trawl fishery of South Carolina, USA

In the United States, interactions between the shrimp trawl fishery and bottlenose dolphins are known to exist; however, the level of mortality is largely unknown, and has not been studied in South Carolina, USA. The current study attempted to determine if interactions between bottlenose dolphins and the South Carolina commercial shrimp trawl fishery pose a significant threat to dolphin populations and if fishery related mortality is underreported. Onboard observations were made during a 25 day (August–December 2010) field study. No dolphin takes occurred during the observational period. These observations focused on direct physical interactions with the gear and depredation behaviours. Additionally, a subsample of the shrimp fishery in South Carolina was asked to participate in a mailed survey. The survey included questions related to gear, dolphin observations, and the status of the shrimp fishery. This paper also examines historical dolphin stranding data from the NOAA/CCEHBR MMIS database for signs of shrimp fishery interactions. A three-tiered flow diagram was developed to characterise each stranding case according to the likelihood that mortality resulted from trawler interaction. Field results point to significant dolphin presence around commercial trawlers (x2 = 23.406, p < 0.001). Survey results showed 12 unreported incidents of shrimp trawl fishery mortality of dolphins. Finally, stranding records revealed several more cases with signs of possible trawler interaction. The current US National Marine Fisheries Service (NOAA) designation of the fishery as a Category II fishery is correct. Increased observer coverage and improved communication with the fishery on the importance of reporting takes is warranted.

Interactions between U.S. biofuels policy and the Endangered Species Act

The Renewable Fuel Standard (RFS) is the primary policy governing the use of biofuels in the United States. Following the 2007 enactment of the RFS, there has been substantial expansion in the use of cropland to produce biofuel feedstocks, including corn and soybeans. Both the conversion of land and the ongoing cultivation of these crops can, depending on management practices, lead to negative environmental outcomes including degraded water quality, increased water use, increased greenhouse gas emissions, and loss or degradation of wildlife habitat. These outcomes have the potential to affect threatened and endangered species protected under the U.S. Endangered Species Act (ESA). The ESA requires federal agencies to consult with the U.S. Fish and Wildlife Service or the National Marine Fisheries Service to ensure that an agency's actions are not likely to jeopardize the existence of imperiled species, nor result in the destruction or adverse modification of their habitat. However, formal consultation has not yet been completed between the U.S. Environmental Protection Agency—the agency charged with implementing the RFS—and the wildlife services, thereby hindering mitigation or remediation of potential impacts. This analysis explores the likely effects of the RFS on land use changes and critical habitat, illustrates example pathways by which threatened and endangered species may be affected, and proposes solutions to help redress this harm. The findings suggest a need for further consultation and assessment of the interactions between the RFS and ESA as well as additional research to support the species-conservation and policymaking processes.

Applying technical guidance from the USA for management of impacts of anthropogenic noise on wildlife in other countries: the Canadian context

Technical Guidance from the US National Marine Fisheries Service recommends Federal agencies use estimated thresholds for peak sound pressure levels and weighted cumulative sound exposure levels for the onset of permanent (and temporary) hearing threshold shifts in marine mammals. These dual metrics were developed to inform impact assessments within the US legal landscape. Despite its merits, the Technical Guidance contains uncertainties due to limited data on marine mammal hearing and auditory response to noise. The underlying assumptions about how representative existing data are for all marine mammal species also create limitations in the applicability of the Technical Guidance. These limitations warrant consideration before the Technical Guidance can be applied effectively in other jurisdictions with different legal standards. Using the Canadian legal framework as a working example, we found that many Canadian species are underrepresented in the dataset informing the Technical Guidance. The Technical Guidance also does not address all relevant noise impact types. Thus, the Technical Guidance alone cannot address all Canadian legal standards and, if the Technical Guidance is incorporated, some adjustments to the criteria within may be needed to meet the precautionary requirements of many Canadian legal standards.

EPA proposes restrictions on carbaryl insecticide

The US Environmental Protection Agency is proposing to limit certain uses of the widely used insecticide carbaryl. The carbamate pesticide is neurotoxic and poses health risks to workers and endangered species, the agency says in a proposed interim decision released Dec. 1. In 2021, the EPA identified potential human health and ecological risks for some uses of carbaryl, including residential ones. It also found that carbaryl is likely to harm more than 1,000 endangered species. The agency is consulting with the Fish and Wildlife Service and the National Marine Fisheries Service to determine what mitigation measures are needed to protect affected species. In the meantime, the agency is proposing measures to protect two species—steelhead trout and wireweed. It is also proposing steps to limit spray drift and runoff to protect pollinators and nontarget species. Carbaryl is used on several agricultural crops, including apples, asparagus, melons, and tomatoes. The EPA is

Decline in on-demand fishing gear costs with learning

Gear entanglement and vessel collisions are the major known causes of injuries to the critically endangered North Atlantic right whale (Eubalaena glacialis) and other marine animals. Whale entanglements often occur in endlines (the fixed vertical lines between fishing traps and surface buoys) and removal of these lines in “on-demand” or “ropeless” fishing gear has been presented as a potential solution. These fishing systems use acoustic and timed releases to locate and retrieve a submerged trap, endline, and buoy (or lift bag or spool) to the surface. On-demand fishing gear commercially in use costs up to $8,000 for a deck unit and up to $4,000 per acoustic release. Developers expect on-demand fishing component costs to drop as production ramps up. The correlation between production cost or labor hours per unit and cumulative production have been described as ‘experience curves’ or ‘learning curves.’ The learning model is the most common approach to projecting production costs in electronics and other high-tech industries, with the log-linear model based on the Wright learning curve the most frequently used modelling approach. Wright’s equation is used to calculate on-demand fishing gear costs for northeastern U.S. commercial fishing vessels operating in federal lobster management areas. These vessels represent approximately 70% of entanglement risk, estimated by the National Marine Fisheries Service. The use of on-demand gear would therefore initially be most effective in reducing the risk of whale entanglement (and mortality) in commercial fishing areas in these waters. It is estimated that the cost of on-demand gear for the 1,494 vessels operating in federal waters would total $58.1 million, with an average of $38,899 per vessel if releases were used on all endlines. If vessels fishing 5 or more traps per trawl use a release on 1 endlines per trawl, the total cost is estimated at $38.2 million, with an average of $25,552 per vessel. The initial cost of on-demand fishing gear may be an obstacle to widespread adoption. Funding and loan programs are available and there is precedent for government and community assistance to workers in industries affected by resource management regulations.

Beaked whale dive cycle estimation based on acoustic data from drifting recording systems

Marine Mammal ScienceEarly View NOTE Beaked whale dive cycle estimation based on acoustic data from drifting recording systems Jay Barlow, Corresponding Author Jay Barlow jaybarlow33@yahoo.com orcid.org/0000-0001-7862-855X National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries Science Center, California (retired) Correspondence Jay Barlow, 5072 Gasconade Avenue, San Diego, CA 92110. Email: jaybarlow33@yahoo.com Contribution: Conceptualization, Data curation, Formal analysis, Funding acquisition, ​Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing - original draft, Writing - review & editingSearch for more papers by this authorJennifer L. K. McCullough, Jennifer L. K. McCullough orcid.org/0000-0003-4212-7846 National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Pacific Islands Fisheries Science Center, Honolulu, Hawaii Contribution: Conceptualization, Data curation, Resources, Supervision, Validation, Visualization, Writing - review & editingSearch for more papers by this author Jay Barlow, Corresponding Author Jay Barlow jaybarlow33@yahoo.com orcid.org/0000-0001-7862-855X National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries Science Center, California (retired) Correspondence Jay Barlow, 5072 Gasconade Avenue, San Diego, CA 92110. Email: jaybarlow33@yahoo.com Contribution: Conceptualization, Data curation, Formal analysis, Funding acquisition, ​Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing - original draft, Writing - review & editingSearch for more papers by this authorJennifer L. K. McCullough, Jennifer L. K. McCullough orcid.org/0000-0003-4212-7846 National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Pacific Islands Fisheries Science Center, Honolulu, Hawaii Contribution: Conceptualization, Data curation, Resources, Supervision, Validation, Visualization, Writing - review & editingSearch for more papers by this author First published: 09 November 2022 https://doi.org/10.1111/mms.12987 Funding information: Bureau of Ocean Energy Management, Grant/Award Number: M17PG00024; NOAA Pacific Islands Fisheries Science Center; NOAA Southwest Fisheries Science Center; U.S. Navy, Chief of Naval Operations, Grant/Award Number: N0002518GTC032-06; U.S. Navy, Pacific Fleet, Grant/Award Number: N0007018MP4C587-01 Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Early ViewOnline Version of Record before inclusion in an issue RelatedInformation

A Collaborative Aerial Survey of Coastal Pelagic Species in Nearshore California Waters

Pacific Sardine Sardinops sagax and Northern Anchovy Engraulis mordax are commercially important West Coast fish stocks managed within the Coastal Pelagic Species (CPS) complex by the Pacific Fishery Management Council and National Marine Fisheries Service. Before 2020, survey indices used in Pacific Sardine stock assessments did not explicitly account for nearshore biomass, which presumably had been relatively small compared to the total biomass of the population, but since 2015, has been a more substantial component of total biomass. During the recent Pacific Sardine stock decline, the California Department of Fish and Wildlife and the California Wetfish Producers Association collaborated on an aerial survey off California to estimate nearshore (within 3,600 m from shore) CPS biomass to inform assessments. This project has also involved federal fisheries biologists and Pacific Fishery Management Council advisory bodies and committees, representing a unique collaborative effort to improve data used in CPS fisheries management. We will discuss successes, issues, and challenges in implementing this nontraditional survey and how these data can continue to inform future stock assessments.