2024 Alaska Fisheries Science Center Seminar Series
2024 Seminar Series held virtually using Webex.
The 2024 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 seminar series starts in late February and ends in early May. We host around 10 weekly talks on Tuesdays at 10 am Pacific Time, with speakers from both inside and outside of the Alaska Fisheries Science Center.
We hope to see you there! Amanda.Warlick@noaa.gov and Alexandra.Dowlin@noaa.gov
2024 AFSC Seminar Series Overview Poster
2024 AFSC Seminar Series Poster
February 27, 2024 —Craig Faunce
Craig Faunce Presentation Flyer
Tuesday, February 27th @ 10 am Pacific
Eyes on the water: Fishery Observers and their role as enforcement assets
Intensively managed, well-regulated, and well-enforced fisheries are typified by low incidences of illegal, unregulated, and unreported (IUU) fishing and also possess stock levels that are above target levels of exploitation or are rebuilding. Fisheries operating in the Federal waters off Alaska are managed with near real-time quota management and have been monitored with observers for over 50 years. Observers in our region are deployed into fisheries year-round and typically operate independently for up to several months at-sea and in remote ports. Observers in the North Pacific are required to collect unbiased information on the extraction of marine resources while also reporting potential violations of maritime law. They must therefore act as scientists and enforcement assets. The scientific value of observer data to support quota management and stock assessments is relatively well understood compared to the value of observer data to combat IUU. This year marks the 25th anniversary of the start of digital observer statements, i.e., reports of potential law violations in the North Pacific. The Fisheries Monitoring and Analysis (FMA) Division of the AFSC has been collaborating with the Office of Law Enforcement Alaska Division (AKD) for the past eight years to summarize, analyze and publicly report potential IUU in Federal waters. This presentation highlights the results of three teams that have iteratively improved the way observer statements are recorded, analyzed, and presented. The utility of these statements in documenting unlawful behavior over time, the challenge of increasing regulation, how reporting accuracy is being improved, and newly quantified risks of sexual assault and harassment (SASH) faced by observers will be presented. These efforts are only examples of a continuous effort to better inform policy makers of potential issues and to improve the efficiency and effectiveness of maritime law enforcement.
WebEx Recording- Craig Faunce 2024 Seminar Series
March 5, 2024 —Dean Grubbs
Dean Grubbs Presentation Flyer
Tuesday, March 5th @ 10 am Pacific
Smalltooth sawfish: 20 years after ESA listing, is there hope for this critically endangered marine predator?
Understanding the ecology of large marine predators is challenging due to their naturally low abundances, a concealing environment and the logistical constraints associated with capture and handling. These difficulties are compounded for rare and imperiled taxa. Smalltooth sawfish (Pristis pectinata) populations declined dramatically in the last half of the 20 th century throughout the range due to overfishing and habitat loss. The species is restricted to the Atlantic Ocean, historically occupying coastal waters from North Carolina to central Brazil in the western Atlantic as well as most of West Africa in the eastern Atlantic. The only known viable populations remaining are in the U.S. (Florida) and The Bahamas (mostly Andros Island). Smalltooth sawfish have been protected in Florida since 1992, and in 2003 the U.S. population was listed as Endangered under the U.S. Endangered Species Act, the first native marine fish to be listed. While all international trade is prohibited through CITES Appendix I, sawfish can be harvested legally in countries such as The Bahamas with no specific protections in place. Since 2011, graduate students and I have been using fishery-independent surveys as well as acoustic and satellite telemetry to study migration, habitat use, and changes in distribution and relative abundance to assess the viability of U.S. and Bahamian smalltooth sawfish populations. Our work to date suggests the U.S. population is relatively large and robust and following decades of protection, there are positive signs that recovery is taking place. In contrast, the Bahamian population appears to be much smaller and perhaps susceptible to extirpation. I will discuss the research methods we use and our major findings after more than a decade of work on this very large, unusual, and highly vulnerable marine predator.
WebEx Recording- Dean Grubbs 2024 Seminar Series
March 12, 2024 —Zoe Almeida
Zoe Almeida Presentation Flyer
Tuesday, March 12th @ 10 am Pacific
Warmer, earlier, faster: Cumulative effects of Gulf of Alaska heatwaves on the early life history of Pacific cod
Warming climates are creating unprecedented environmental conditions, such as more frequent and intense marine heatwaves (MHWs), that directly impact phenology and growth of fish and other marine organisms. Understanding individual phenological and growth responses to temperature is critical to predict species and population responses to climate change; however, doing so requires disentangling the effects of temperature on phenology, size, and growth in wild populations. We quantified the relationships between temperature and hatch timing, size-at-age, and early growth in a population of Pacific cod (Gadus macrocephalus) affected by recent MHWs in the Gulf of Alaska. Pacific cod juveniles were collected near Kodiak Island, Alaska, USA, across 11 years, categorized as before (2007, 2009–2010, 2012–2014), during (2015, 2016, 2019) and between (2017, 2018) multiple recent MHWs. We estimated age and growth with otolith structural analysis. Hatching occurred on average 14 days earlier during MHWs and 26 days earlier between than before MHWs. Approximately 53% and 16% of these respective shifts in timing were attributable directly to warmer temperatures during incubation. Size-at-age was similar across periods at younger ages (90 days), but approximately 7 mm and 11 mm larger than before MHWs at older ages (132 days) during and between MHWs, respectively. Observed differences in growth rate could not fully account for the observed increases in size-at-age. We found that temperature alone could not explain the changes in growth and phenology; thus, factors such as parental effects, epigenetics, and selection likely contributed.
WebEx Recording- Zoe Almeida 2024 Seminar Series
March 19, 2024 —Jenny Stern
Jenny Stern Presentation Flyer
Tuesday, March 19th @ 10 am Pacific
Quantifying the timing and rate of hair growth in polar bears
The foraging ecology of wildlife populations has important implications for individual health, population productivity, and distribution patterns. In polar bears, food resources and foraging behavior primarily affect population dynamics via effects on cub production and survival. Much of what is known about the feeding ecology of polar bears is based on analyses of various tissues collected from capture-based research efforts, harvested animals, or non-invasive approaches. However, inference about diet from hair has been limited by a lack of quantitative data on the timing of the molt and hair growth rates. We designed methods to quantify hair growth rates in bears through a collaboration with zoos. Through this process, we identified and implemented an effective visual and biochemical approach proven safe for humans and other animals to quantify the rate and timing of hair growth. The study included a) the application of a small patch of hair dye on the rump or foreleg and, b) feeding an isotopically-labeled ingestible glycine (amino acid) capsule that ‘marks’ time at a particular location as it is incorporated within the hair. Both methods quantified hair growth between the time the bleach or dye was applied, or the glycine marker was fed and the time that hair was collected. We collected hair at regular intervals (every 1-2 weeks) from locations on the bear consistent with commonly sampled collection points in wild-caught bears. Hair samples were used to determine the timing of incoming new hairs, preliminary growth rates, and the incorporation times of glycine. This study provides the first step for developing a foundation for incorporating seasonality in the wild-collected polar bear hair samples by assessing growth over an annual cycle.
WebEx Recording- Jenny Stern 2024 Seminar Series
March 26, 2024 —Melanie Esch
Melanie Esch Presentation Flyer
Tuesday, March 26th @ 10 am Pacific
Assessing the invasion risk of the Indo-Pacific regal demoiselle to reefs of the western Atlantic
Alien species have had dramatic negative impacts in marine habitats around the world and are an additional stressor for Caribbean coral reefs that are experiencing dramatic heath declines due to other anthropogenic effects. For example, the release of carnivorous lionfish onto reefs in the Caribbean has led to predation on native species, competition with native mesopredators, and potential effects on benthic assemblages. The Indo-Pacific native Neopomacentrus cyanomos, was first documented on several reefs near Coatzacoalcos, Mexico in 2013. This population rapidly spread throughout the northern Gulf of Mexico with the invasion front now in South Florida and the Florida Keys. We investigated the habitat preferences and thermal physiology of N.cyanomos to assess potential range expansion and impacts on native fish communities in the Caribbean. Our results can be used by interested stakeholders to efficiently monitor for the arrival of N.cyanomos into new areas and aid potential removal efforts to try and slow the spread of this new invader.
WebEx Recording- Melanie Esch 2024 Seminar Series
April 2, 2024 —Derek Chamberlin
Derek Chamberlin Presentation Flyer
Tuesday, April 2nd @ 10 am Pacific
Otoliths and eye lenses: modern approaches to age validation
Age is a fundamental parameter in population ecology and fisheries science. Age-structured stock assessments rely on accurate and precise estimates of age to estimate stock status and sustainable fishing limits. Ensuring the accuracy of age estimates, through age validation, is thus a critical aspect of fisheries management. The bomb radiocarbon (14C) chronometer is frequently utilized to validate age estimation in marine fishes, with birthyear Δ14C traditionally measured in otolith cores. Otoliths are approximately 12% C by mass, with the C primarily (70-80%) derived from inorganic sources. This has limited the utility of the bomb radiocarbon chronometer to fishes that spend their juvenile life stage in the well-mixed surface layer, as DIC becomes progressively depleted in 14C at increasing depth. Current analytical limits require ~1 mg of otolith material (~100 µg of C) for the most accurate and precise analysis of Δ14C. Eye lens cores are a promising alternative. Like otoliths, eye lenses form prior to hatching, grow throughout a fish’s life, and are metabolically inert once formed. Unlike otoliths, eye lenses are approximately 50% C by mass and this C is entirely metabolically derived, with phytoplankton from the surface layer as the basal source. This means only ~200 µg of eye lens material is required for analysis. Furthermore, because eye lenses are composed entirely of metabolic carbon they can be used as a source of surface-derived 14C for deepwater species. Thus, using eye lens cores expands the suite of fishes we can validate ages via bomb radiocarbon chronometer and, in turn, improves age-based assessment techniques for managing fishery stocks. However, the bomb radiocarbon chronometer is limited to validating ages only back to the 1960s, the period of rapid increase in 14C. Amino acid racemization in eye lens has emerged as a potential alternative age predication and validation tool that is not temporally limited. Both methods and their application will be presented along with potential future applications in Alaska waters.
WebEx Recording- Derek Chamberlin 2024 Seminar Series
April 9, 2024 —Christina Conrath
Christina Conrath Presentation Flyer
Tuesday, April 9th @ 10 am Pacific
The Alaska Coral and Sponge Initiative: past, present, and future
The NOAA Deep Sea Coral Research and Technology Program was established under the Magnuson-Stevens Fishery Conservation and Management Act of 2007 to support deep-sea coral ecosystem research and aid resource managers in the conservation and management of deep-sea coral and sponge habitats. This program rotates funds through the NMFS regions and has supported research in Alaska from 2012-2014 and 2020-2023. Objectives of the first Alaska initiative included mapping the distribution and abundance of sponge and coral, producing habitat and substrate maps, examining the contribution of coral and sponge habitats to fisheries production, examining the impacts of fishing gear on this habitat, and researching recovery and recruitment rates. Accomplishment of the first initiative include the completion of 11 research cruises, 216 camera transects in the Aleutian Islands, 250 camera transects in the eastern Bering Sea, 21,910 in-situ measurements of height for corals and sponges, collecting over 500,000 images, and 853 records of coral locations from visual surveys added to the NCEI database. One important accomplishment of the first initiative was the development of coral and sponge habitat models for the Gulf of Alaska, Aleutian Islands, and Eastern Bering Sea and the validation of these models in the Aleutian Islands and Eastern Bering Sea canyons. These data have been used to inform Essential Fish Habitat and fishing effects models. The research accomplished by this initiative formed a baseline to support the development of the science plan for the second initiative in 2020. Funding for this initiative has supported four successful large field expeditions throughout the Gulf of Alaska and Aleutian Islands as well as several smaller research projects. In addition, during this initiative a new coral and sponge field guide has been developed, new sponge species have been identified, and national and international partnerships have been developed. Accomplishments of the second initiative include 6 research cruises, 302 camera transects in the Gulf of Alaska (76 in offshore waters), 102 camera transects in the Aleutian islands, 6 ARMS plates deployed, 395 eDNA collections and multiple species of sponges and corals collected for taxonomic and other studies. Research between initiative years will focus on data recovery, providing data to support ecosystem based management and EFH programs, continuing to increase our understanding coral and sponge communities throughout Alaska and how they support commercial fishery resources, and continuing to develop national and international partnerships within and beyond NOAA.
WebEx Recording- Christina Conrath 2024 Seminar Series
April 16, 2024 —Matthew Lettrich
Matthew Lettrich Presentation Flyer
Tuesday, April 16th @ 10 am Pacific
Marine Mammal Climate Vulnerability Assessment: A Focus on the U.S. West Coast and Alaska
Vulnerability assessments provide a framework for evaluating climate impacts over a broad range of species using currently available information. We conducted a trait-based climate vulnerability assessment using expert elicitation for 128 marine mammal stocks and stock groups in U.S. waters of the Pacific and Arctic Oceans. Our approach combined the exposure (projected change in environmental conditions) and sensitivity (ability to tolerate and adapt to changing conditions) of marine mammal stocks to estimate vulnerability to climate change, and categorize stocks with a vulnerability index. This presentation will provide a description of the vulnerability assessment process, an overview of regional results, and engage with the audience on possible next steps for the assessment, all with a focus on the U.S. West Coast and Alaska.
WebEx Recording- Matthew Lettrich 2024 Seminar Series
April 23, 2024 —Kimberly Ledger
Kimberly Ledger Presentation Flyer
Tuesday, April 23rd @ 10 am Pacific
From tanks to sea: environmental DNA applications of cod in Alaska
Environmental DNA (eDNA) has significant potential to detect species that pose challenges for non-molecular sampling methods. However, a key obstacle in applying eDNA data for ecosystem management is uncertainty surrounding the ability to estimate abundance or biomass. In this study, we use experimental tanks with known biomasses of multiple species to explore the feasibility of (1) estimating species proportions from eDNA metabarcoding data and (2) scaling metabarcoding proportions with absolute eDNA concentrations of a single species obtained with qPCR to estimate absolute eDNA concentrations of additional species. The focal species for this study were three gadid fish that are key components of marine ecosystems in Alaska: Walleye pollock (Gadus chalcogrammus), Pacific cod (Gadus macrocephalus), and Arctic cod (Boreogadus saida). After designing gadid-specific metabarcoding primers and accounting for PCR biases in the metabarcoding data, we found corrected read proportions closely approximated the true biomass proportions of species. Furthermore, we found strong relationships between absolute eDNA concentration and absolute biomass for Arctic cod and Pacific cod using quantitative metabarcoding data combined with estimates of Walleye pollock eDNA concentration derived from qPCR. These findings suggest that it is possible to accurately quantify compositional relationships and estimate metrics of biomass for gadids in real-world scenarios. Furthermore, this work provides a framework for developing primers and analytical approaches that can be applied to other species to improve the utility of eDNA for marine ecosystem management.
WebEx Recording- Kimberly Ledger 2024 Seminar Series
April 30, 2024 —Cecilia O'Leary
Cecilia O'Leary Presentation Flyer
Tuesday, April 30th @ 10 am Pacific
Tracking down the groundfish that ignore our survey footprint: improving bottom trawl survey index accuracy
This talk will go over two critical issues facing groundfish surveys in the Bering Sea and Gulf of Alaska systems, respectively: shifting fish distributions and untrawlable habitats. The dynamic nature of groundfish distributions, driven by ocean warming, poses hurdles for surveys. As species migrate and habitats shift, effective management requires a comprehensive understanding of groundfish distributions. I will discuss how international collaborations play a pivotal role in this endeavor, facilitating the integration of disparate datasets and tracking groundfish beyond traditional survey boundaries. Model-based biomass estimates for Bering Sea groundfishes (walleye pollock, Pacific cod, and Alaska plaice) enable combining data sets to inform fisheries-independent survey footprint coverage to help with conservation and management strategies in the face of environmental change. Moreover, across the Gulf of Alaska and Aleutian Islands, significant portions of survey areas are inaccessible to fisheries-independent bottom trawl gear to survey due to rocky bottoms, high relief, and steep seafloors. Overlooking these untrawlable habitats in current abundance estimations risks biasing assessments, as assumptions of uniform fish density with trawlable areas fall short. To address this, we explore innovative methods such as lowered stereo-camera systems to integrate UT habitat data, enhancing the accuracy of abundance models, particularly for groundfish species dependent on rocky habitats.
Join by computer at:
WebEx meeting number:
2760 456 5021
Password:
2024AFSC
Or by phone:
1 (415) 527-5035
Access code:
2760 456 5021