2021 Alaska Fisheries Science Center Seminar Series
2021 Seminars will be held virtually using Webex - Tuesdays @ 10am Pacific.
The Alaska Fisheries Science Center seminar series provides a venue for researchers to present new research on fish, fisheries management, marine mammal ecology, and habitats across Alaska’s marine ecosystems. We encourage speakers to present work that is of broad interest to the Alaska marine science community, and welcome speakers and attendees from both inside and outside the AFSC. The series features around 10 speakers annually, with seminars occurring weekly from late winter-spring. Seminars occur Tuesdays at 10 am.
May 4, 2021 - Matthew Rogers
Tuesday, May 4, 2021 - 10:00 am Pacific time
Hot tub time machine: using stable isotope analysis of Northeast Pacific humpback whale baleen to infer dynamic foraging habits and evidence of starvation in response to a marine heatwave.
From 2014-2016, researchers observed the strongest marine heatwave ever recorded in the North Pacific Ocean. Food web dynamics were disrupted during the marine heatwave, which likely caused nutritional stress in humpback whales. For the first time in this population, we analyzed nitrogen and carbon stable isotopes in humpback whale baleen to investigate whale foraging ecology before, during, and after the marine heatwave. We hypothesized that if a population-level change in foraging ecology occurred during the marine heatwave, it would be reflected in baleen isotopic patterns.
We found that individual baleen plates record 4-5 years of isotopic information in humpback whales (n=9) as inferred from annual baleen δ15N oscillations. We estimate a baleen growth rate of 16.9+/-3.9 cm/yr. We determined likely forage types for individual whales (zooplankton vs. forage fish) and observed apparent differences in nearshore vs. offshore feeding among individuals from baleen δ13C profiles. We did not find any abrupt population-level foraging shifts after the onset of the marine heatwave. We also found an anomalous, steadily increasing δ15N pattern in the most recently grown baleen of multiple whales that died during the marine heatwave, potentially indicating severe nutritional stress or starvation in the weeks or months preceding death.
April 27, 2021 - Leah Zacher
Tuesday, April 27, 2021 - 10:00 am Pacific time
Tracking Crabs with Drones: Seasonal Distribution of King Crabs in Bristol Bay.
Much uncertainty still exists on the distribution of Bering Sea crab stocks outside summer survey periods, making it challenging to delineate essential habitats across life stages, define environmental predictors of abundance and distribution, and mitigate bycatch in other fisheries. One key management tool to reduce king crab bycatch are fixed closures that prohibit bottom trawl gear. However, a static closure for a highly mobile species, immediately presents problems. Most king crab distribution data comes from summer surveys, while bycatch in trawl fisheries primarily occurs in winter, making it difficult to evaluate the effectiveness of closure areas. To address this mismatch, the AFSC Shellfish Assessment Program began a collaborative research effort with the Bering Sea Fisheries Research Foundation to elucidate year-round Bristol Bay red king crab distributions. Crabs were tagged with acoustic tags that continuously transmit a unique identification number and the bottom water temperature. To re-locate crabs, autonomous surface drones equipped with acoustic receivers were deployed to search for tagged crabs by performing transects across Bristol Bay. In contrast to traditional tagging, this tagging method has the advantage of being fishery independent; in addition, because acoustic tags can be retained through a molt, the same tagged individuals can potentially be located over several years.
April 20, 2021 - Louise Copeman
Tuesday, April 20, 2021 - 10:00 am Pacific time
The importance of marine lipids in warming Arctic food webs: tales of juvenile fish and crab.
The storage of high levels of marine lipids in arctic consumers is generally viewed as an adaptation to extreme seasonal environments that are characterized by long periods of reduced food availability. Lipids are the most efficient means of energy storage as they contain twice the energy per unit mass as other macronutrients. At the Marine Lipid Ecology Lab (FBE program, Newport, Oregon) we are using both laboratory and field-based approaches to understand how changing environmental conditions are impacting the condition of juvenile fish and crab. The analyses of consumer total lipids combined with storage lipid classes is a sensitive method for assessing animal condition. We combine this approach with the analysis of fatty acid biomarkers to help elucidate trophic mechanisms that drive changes in fish and crab condition. Two examples of this approach will be discussed featuring juvenile Chukchi Sea Arctic cod (Boreogadus saida) and juvenile Bering Sea snow and Tanner crab (Chionoecetes spp.). In both cases (pelagic and benthic), we measured a reduction of lipid storage during recent years of intense warming.
April 13, 2021 - Elizabeth McHuron
Tuesday, April 13, 2021 - 10:00 am Pacific time
One fish, two fish, small fish, big fish! Northern fur seal consumption of walleye pollock and considerations for ecosystem-based fisheries management in the eastern Bering Sea.
Marine mammals are significant consumers of prey populations, and as such, should be considered in ecosystem-based fisheries management (EBFM) when they prey on commercially valuable species. The Eastern Pacific stock of northern fur seals (Callorhinus ursinus), which has been declining since the late 1990s, overlaps spatially and temporally with the eastern Bering Sea walleye pollock (Gadus chalcogrammus) fishery during the summer and fall. There have been few recent attempts to quantify fur seal pollock consumption despite the ongoing decline, which is an important first step in understanding the role of food availability in the decline and in determining the need to incorporate them into EBFM of pollock. To remedy this, we developed age- and sex- specific bioenergetic models and combined these with empirical diet estimates of fur seals from the Pribilof Islands. The resulting size-specific estimates of pollock consumption were compared with that of the three fish predators (pollock, cod, and arrowtooth flounder) currently included in the multi-species stock assessment model CEATTLE. Fur seal consumption of pollock rivaled that of individual fish predators. I will discuss interannual variation in size-specific pollock consumption by fur seals, why previous attempts likely underestimated fur seal consumption of walleye pollock, and ongoing efforts to incorporate fur seals into the CEATTLE model.
April 6, 2021 - K.C. Wilson
Tuesday, April 6, 2021 - 10:00 am Pacific time
Acoustic and camera-based methods to observe fish and fish behavior: Applications at spawning aggregations and in fishing gear.
Both acoustics and underwater cameras enable the observation of marine fish and fish behavior in-situ. Active acoustics are widely used to characterize fish and/or invertebrate distributions, and provide biomass estimates for stock assessments. Other acoustic methods, such as acoustic tagging and passive acoustics, are also important for science and management. Cameras are frequently used to make in-situ observations at fixed locations, and can also be used to conduct video transects and census and length measurements. Together, acoustics and cameras provide a powerful combination to observe fish and fish behavior. I will present studies from two projects that have combined acoustic and camera-based methods to address research questions related to fish spawning aggregations and commercial fishing bycatch reduction devices.
March 30, 2021 - Matthew Kemp
Tuesday, Mar. 30, 2021 - 10:00 am Pacific time
Can technology augment the role of observer sampling? Designing sampling methods for fisheries observers in the age of electronic monitoring.
Early forms of Electronic Monitoring (EM) Systems and their application in fisheries management have significantly aided the speed and accuracy of catch reporting and compliance monitoring. EM allows for the quantification of total catch weight by haul, monitoring of sensitive species accounting, and provided a means to share fishing effort information in real-time. However, technology has failed to fully augment the need for human involvement in the process of collecting the data necessary to appropriately manage such a complex resource. EM technologies cannot yet account for total catch nor meet biological data collection requirements. All data collections requiring observer involvement will have to be offset to assigned observers at the receiving shoreside processing plant. The implications of the suspected loss of spatial and temporal resolution within the data collected is of great concern to stock assessors and other end users. So, is it possible for technology to aid in the collection of data while not hindering the resulting data collected?
In order to determine the efficacy of this process, EM systems will be deployed on Bering Sea and Gulf of Alaska Pollock Catcher Vessels in lieu of human observers and will monitor regulatory compliance concerns while the vessel is at sea. Upon its return to a processing facility, each vessel will be sampled to mitigate data lost by the displacement of an observer. These data will include biological specimens (e.g. otoliths, sex, length frequencies etc.) and a census of select prohibited species such as salmon at a minimum. To ensure these data are representative, a rigorous sampling methodology will be designed and implemented by plant observers assigned to participating shoreside plants in January 2020. Each data collection will pose unique challenges for the observer; plant diagrams will need to be consulted to evaluate access and guarantee the feasibility of the collection given each applicable method and its expected outcome. In order to minimize any negative effects of altering the point of collection, multiple random designs will be considered, options will be evaluated with the anticipated outcome in mind to ensure end data quality and that the amounts meet the needs of each end user. Ultimately, the end product should allow for the collection of representative data, work to ensure that methods are repeatable, and all resulting data is defensible for the purposes of management.
March 23, 2021 - Dr. Tiffany Stephens
Tuesday, Mar. 23, 2021 - 10:00 am Pacific time
Alaskan seaweed mariculture: Building a new industry with people and environment in mind.
The Alaskan coastline provides an unprecedented setting to develop a sustainable and resilient mariculture industry that can advance economic opportunity, locally and regionally, while also increasing national food security. Nested in this industry is the cultivation of seaweeds, which can be leveraged for commercial sale, to support other mariculture initiatives, and can also support conservation concerns. In 2017, seaweed mariculture reached a commercially-relevant scale of cultivation and continues to expand, with an enormous amount of interest expressed along coastlines in southern Alaska. I will discuss the continued development of this industry, from seed to value-added sale, with focus on our team’s efforts at Seagrove Kelp Co., a vertically-integrated and for-profit company situated in southern Southeast Alaska. I will also comment on this industry in context ecosystem-wide hopes and concerns as this industry scales.
March 16, 2021 - Suzanne Romain
Tuesday, Mar. 16, 2021 - 10:00 am Pacific time
Development of EM Computer Vision Systems and Machine Learning Algorithms for Automated Catch Accounting in Alaska Fisheries: An overview of the FMA innovation project.
Successful fisheries management is dependent upon the collection of data from fishing activities. Electronic monitoring (EM) has been shown to be an effective tool to meet fisheries monitoring objectives in compliance-based programs. The EM Innovation (EMI) project, supported by the Fisheries Monitoring and Analysis Division (FMA), is researching and piloting cost-effective and durable machine vision (MV) advancements for EM camera system deployments, with the goal of providing real time automated catch accounting reporting.
EMI research consists of the development and deployment of camera systems for acquiring imagery and the development and integration of automated MV algorithms. Algorithms have different requirements based on the image types and the fisheries environment, and multiple functional applications where the algorithms can be useful were identified. These include automated species detection, identification & length estimation of fish as it is caught at the rail of fixed gear vessels; species identification of fish images collected in controlled environments; the detection, count and length estimation of Halibut bycatch; and the isolation, detection and count of salmon from processing plant belts containing multiple species of fish, as well as the detection and monitoring of crew member activity on vessel decks.
March 9, 2021 - Bryan Costa and Chris Caldow
Tuesday, Mar. 9, 2021 - 10:00 am Pacific time
Potential Benefits of the Expanding Pacific Research and Exploration of Submerged Systems (EXPRESS) Campaign in Alaska.
Data on deep sea organisms and their associated habitats are critical for a wide range of decisions about natural resources, uses and hazards within the United States EEZ. Although this information is critical, large gaps in our understanding of the seafloor still exist for many U.S. federal management and regulatory agencies. In 2018, individuals from NOAA, BOEM, USGS and MBARI came together to launch the Expanding Pacific Research and Exploration of Submerged Systems (EXPRESS) Campaign. The focus of this effort was to leverage their participant resources to fill common, high priority data gaps in the U.S. West CONUS Coast (WCC). To date, EXPRESS partners have completed 326 days at sea on 9 different research vessels on the WCC with more cruises planned in 2021. In FY2020, NOAA's Deep Sea Coral Research and Technology Program's initiative began in the Alaska region. This initiative highlighted the potential need for a similar EXPRESS-like working group to help coordinate the acquisition of deep-sea data offshore of Alaska. Initial conversations about an Alaska EXPRESS Campaign were held in early 2021 to solicit interest and input from federal agencies actively collecting deep-sea data in the Alaska region. The goal of this presentation is to continue to build on these discussions about why, how and who an EXPRESS-like Campaign would potentially benefit in the Alaska region.
March 2, 2021 - Lisa Eisner
Tuesday, Mar. 2, 2021 - 10:00 am Pacific time
Environmental impacts on Walleye Pollock distribution across the Eastern and Western Bering Sea shelf.
Adult and juvenile (age-1) walleye pollock were sampled by the US NOAA AFSC summer bottom trawl survey in 2010, 2017, 2018, and 2019 in the northeastern and southeastern Bering Sea, with profiles of temperature collected concurrently. Similarly, the Russian Research Institute of Fisheries and Oceanography collected adult and juvenile pollock and temperature profiles on summer bottom trawl surveys in the northwestern Bering Sea. Results from these surveys show that adult pollock abundance in recent years (2017, 2018, 2019) has increased in northern regions of the Bering Sea shelf in both the US and Russian sectors. Lower abundances, compared to historic means, were observed in southern regions of the shelf, suggesting the pollock moved directionally from the south to the north. Changes in sea-ice and bottom temperature (e.g., reductions in ice extent and shrinking of the cold pool), and changes in circulation led to changes in distributions of adult and age-1 pollock. Size structure comparisons between NW, NE and SE sections of the Bering Sea shelf suggest that movement of fish between US and Russian waters may have been highest in 2019, one of the two warmest years, and lowest in 2010, the coldest year.