Call for Abstracts – Due August 1
Atlantic International Chapter Annual Meeting
September 18-20, 2022
The Atlantic International Chapter of the American Fisheries Society is now accepting presentation/poster abstracts for discussion and presentation at our annual meeting which is to be held in person at Sunday River Resort in Newry, Maine (COVID permitting). The meeting will run from Sunday evening September 18th to Tuesday morning, September 20th. More details to follow.
Abstracts should be sent to Dr. Russell Easy ([email protected]). Please indicate the type of presentation (oral/poster) in your email.
Note: there are proposed changes to the AIC Bylaws. They are here.
2022 Meeting Program with Abstracts:
46th Annual Meeting of the Atlantic International Chapter
of the American Fisheries Society
46th Congres annuel du Chapitre international de l’Atlantique
18-20 September 2022
Sunday River, Maine, USA
OFFICIAL SCIENTIFIC PROGRAM
International Year of Artisanal Fisheries and Aquaculture
Sunday, September 18th 16:00 Check-in Begins at Sunday River Resort 17:00 – 19:00 Registration (snacks and beverages provided) 19:00: Informal Welcome (Dr. Russell Easy) SESSION (bold indicates speaker)
19:30 – 19:45 Matt Mensinger – University of Maine. Water temperature and smolt size influence predation risk during reservoir migration
19:45 – 20:00 Sarah Vogel – University of Maine. Collaboration networks within the CRU program
20:00 – 20:15 Justin Stevens – Maine Sea Grant College Program. 20:15 – 20:30 Rosanne MacFarlane – PEI Department of Environment, Energy and Climate Action – Forests, Fish and Wildlife Division. A Fine Kettle of Fish: Implications and Challenges of Aquatic Invasive Fish in Prince Edward Island.
MONDAY, SEPTEMBER 19TH 07:30 – 8:30 Breakfast at Sunday River
08:30 – 08:45 Welcome Address: Pete Emerson, President AIC – Vermont Fish and
Wildlife Department. Dr. Russell Easy, President Elect AIC – Acadia University
Session 1 – Exploring Fish Behaviour
08:45 – 09:00 Robert Jarrett – University of Maine, School of Marine Sciences. Difficulty Breathing: assessing changes in behaviour and measures of vitality of American lobster at reduced oxygen levels.
09:00 – 09:15 Shelby A Perry – University of New Hampshire. The effects of fish size, stocking density, and photoperiod on juvenile lumpfish aggression.
09:15 – 09:30 Jeffrey T Miller – University of New Hampshire. Standardizing eDNA methods for monitoring estuary fish communities.
09:30 – 09:45 Elise N Collet – University of New Brunswick. Brook trout (Salvelinus fontinalis) thermal aggregation thresholds are dynamic across a summer.
09:45 – 10:00 Isabelle Genier – Acadia University. Stable isotope analysis of the nutrient pathways in the Medway River, Nova Scotia.
10:00 – 10:15 Coffee Break
Session B – Stressing Out
10:15 – 10:30 Caitlin R Shanahan – University of New Hampshire. Characteristics of small scale fisheries off the coast of Salary Madagascar and their impacts to a nearby marine protected area.
10:30 – 10:45 Danielle M Frechette – Maine Department of Marine Resources. Run to the sea: Atlantic Salmon smolt emigration timing variability in a changing climate.
10:45 – 11:00 McKenzie Brown – Acadia University. Investigating the effects of stress and CBD treatment on zebrafish epidermal mucus proteins and cannabinoid-associated gene expression.
11:00 – 12:00 Dan McCaw – Keynote. Talk Title: River Restoration in Maine: A Tribal Biologist’s Perspective on Opportunities and Challenges
12:00 – 13:00 Lunch
SESSION – MOVING ON
13:00 – 13:15 Marco Turner – Acadia University. Characterizing offshore lobster movement and distribution patterns within LFA 33 and 34 through a tagging program.
13:15 – 13:30 Cody Dillingham – University of Maine. The Return of Native Sea Lampreys to the Penobscot River, Maine, USA.
13:30 – 13:45 Sophie A Swetz – Northeast Shelf: identifying challenges, opportunities, and barriers through fishermen and manager perspectives.
13:45 – 14:00 Ernie Atkinson – Maine Department of Marine Resources. Applying Dispersal Patterns to Identify Optimal Egg Planting Locations for Atlantic Salmon in Eastern Maine, USA.
14:00 – 14:15 Lara S Katz – University of Maine, Orono. Assessing the Distribution and Abundance of Bridle Shiners in Maine.
14:15 – 14:30 Break
SESSION – POPULATION DYNAMICS
14:30 – 14:45 Alexander M Morgan – University of New Brunswick. Cooler, Bigger; Warmer, Smaller: Spatially Explicit Species and Size Stratification in Behaviourally Thermoregulating Salmonids.
14:45 – 15:00 Valerie Ouellet – Northeast Fisheries Science Center, Orono Maine. The diadromous watershed-ocean continuum.
15:00 – 15:15 Rylee Smith – University of Maine, Orono. Are smallmouth bass a major threat to juvenile Atlantic salmon in Maine? A habitat suitability model approach.
15:15 – 15:30 Tyson Morrill – Plymouth State University. Beebe River Watershed L-TEME: A Ripple Across Regional Conservation.
15:30 – 15:45 Matthew Warner – Acadia University. Lake Trout (Salvelinus namaycush) in Nova Scotia: A Historical Review and Development of a Habitat Suitability Model.
15:45 – 16:00 Jared Lamy – Plymouth State University. Assessing Population Genetic Structure and Hatchery Introgression in Eastern Brook Trout in the Beebe River Watershed.
16:00 – 16:15 Mary Kate Munley – University of New Hampshire. Investigating Whelk Bait Preference and a Future Shift to More Sustainable Baits for the Channeled Whelk Fishery.
16:15 – 17:00 POSTER SESSION
17:00 – 18:30 Hike/swim
19:00 – 21:00 Dinner
21:00 – Social
TUESDAY, SEPTEMBER 20TH 08:00 – 09:00 Breakfast SESSION – COMMUNICATION IS THE KEY
09:00 – 09:15 Sam Nunn – Acadia University Exploring differential expression of MHC related genes in Striped Bass (Morone saxatilis) in response to mercury contamination 09:15 – 09:30 Jacob Reicker – University of New Brunswick, St John Environmental DNA as Surveillance Tool for Anadromous Fishes Upstream of the Mactaquac Generating Station.
09:30 – 09:45 Jaggers Watters-Grey – University of New Brunswick, St John. Beyond species detection: using a novel environmental DNA method to monitor the genetics and abundance of an Atlantic Salmon population.
09:45 – 10:00 Jud Kratzer – Vermont Fish and Wildlife. Response of Brook Trout Biomass to Strategic Wood Additions in the East Branch Nulhegan River Watershed, Vermont.
10:00 – 10:15 Break
10:00 – 12:00 Business Meeting Location
12:00 LUNCH/AWARDS Departure Safe travels
We would like to thank the following sponsors for their support for the Atlantic Chapter of the American Fisheries Society.
New Brunswick Department of Natural Resources and Energy Development
UNH Student Subunit
Quebec Student Subunit
UMaine Student Subunit
Cortland Line Company
Little Pond Nature Prints
PRESENTERS (bold indicates speaker) Keynote Presenter: Dan McCaw
Dan McCaw is the fisheries program manager for the Penobscot Indian Nation on Indian Island, Maine. Dan works with state and federal agencies to develop fisheries management plans for the Penobscot River. He also represents tribal interests during hydropower relicensing and facilitates fish passage studies in effort to protect endangered and threatened fish species.
Applying Dispersal Patterns to Identify Optimal Egg Planting Locations for Atlantic Salmon in Eastern Maine, USA
Ernie Atkinson1,2 and Joseph Zydlewski 3,2
1 Maine Department of Marine Resources, Jonesboro, Maine 04648
2Department of Wildlife, Fisheries and Conservation Biology, University of Maine, Nutting Hall, Room 244, Orono, ME 04469
3 U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit, University of Maine, Orono, ME 04469.
The Gulf of Maine Distinct Population Segment of Atlantic salmon has suffered from habitat loss and exploitation over the last century. Hatchery supplementation has unquestionably prevented the extirpation of the species, but stocking methods represent tradeoffs between survival, domestication, and logistics. Egg planting maximizes wild rearing opportunities which can be important for adaptation. This method, however, is logistically demanding and requires significant labor over a large spatial scale but a short temporal scale dictated by the ontogeny of the fish. Fertilized eggs were hydraulically planted into nine reaches distributed across three drainages, the Narraguagus, Pleasant and Machias Rivers located in Eastern Maine. We then used fall electrofishing to assess the post emergence dispersal of salmon fry. Dispersal patterns were leptokurtic, with the highest observed abundance 250 meters below the planting sites. Mean upstream and downstream dispersals were 250 meters and 500 meters respectively across all reaches. Corresponding habitat data was collected to categorize the general habitat suitability of reaches for egg planting based on published models. These data were then used to develop a suite of suitability scenarios modeled on a stream network. These scenarios were then compared using a Multiple Genetic Algorithm to create a series of Production Possibility Frontier plots to highlight optimal planting locations with the evaluated drainages.
Investigating the effects of stress and CBD treatment on zebrafish epidermal mucus protein composition
Mckenzie Brown, Russell Easy
Acadia University, Wolfville, NS
Cannabidiol (CBD) is a cannabis-derived compound with diverse applications and pharmacological activities. CBD interacts with the Endogenous Cannabinoid System of vertebrates, a body-wide neuromodulatory system, producing a wide array of effects. While the supposed benefits of CBD treatments are well established, more research is needed to fully understand the toxicological impacts and potential adverse effects of CBD exposure. The aim of this research is to explore the apparent effects of CBD in a stressed vertebrate model. Naive wildtype zebrafish were stressed by net chasing then immersed in a CBD or control treatment solution, epidermal mucus was sampled, and water-soluble proteins were extracted. Proteins were separated via SDS-PAGE and protein profiles were examined and compared pre- and post-treatment. Proteins will be identified using mass spectrometry and used to infer which metabolic pathways have been affected by CBD treatment. The goal of this research is to identify changes in protein composition corresponding to stress or CBD exposure.
Brook trout (Salvelinus fontinalis) thermal aggregation thresholds are dynamic across a summer
Elise N. Collet1,2, Tommi Linnansaari1,2,3, and Antóin M. O’Sullivan1,2,4
1FOREM, University of New Brunswick
2Canadian Rivers Institute, University of New Brunswick, Canada
3Biology, University of New Brunswick
4O’Sullivan Ecohydraulics Inc., New Brunswick, Canada
Brook trout (Salvelinus fontinalis), like other salmonids, are cold-water stenotherms that use thermal refuges during thermally stressful events to reduce physiological stress. In the Miramichi River, located in east-central New Brunswick, Canada, brook trout are known to seek thermal refuges when river temperatures are > 21 °C. New research has revealed the time since the last thermally stressful event (TsE) occurred and the frequency with which these events occur (FsE) affects the temperature that triggers future behavioural thermoregulation in Atlantic salmon (Salmo salar) juveniles. When collated, these processes are representative of thermal hysteresis, or more simply, the fish’s behavioural thermoregulation threshold is defined by its thermal history – and can be modelled via a thermal hysteresis model. Here we test the prediction that like salmon parr, brook trout are also affected by thermal hysteresis. We placed custom-made underwater cameras in thermal refuges that took pictures every 10 minutes between 5 AM and 9 PM to observe the onset of aggregations of brook trout beginning in May 2022. Water and air temperatures were measured throughout the summer. The results of our study further our understanding of how behavioural thermoregulation in brook trout is dynamic and how the management of salmonids during thermally stressful events should reflect these findings.
The Return of Native Sea Lampreys to the Penobscot River, Maine, USA
Cody Dillingham1, Danielle Frechette2, Joseph D. Zydlewski3,1
1Department of Wildlife, Fisheries, and Conservation Biology, University of Maine, Orono, ME; 2Maine Department of Marine Resources Bureau of Sea-Run Fisheries and Habitat;
3U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit, University of Maine, Orono, ME
Sea Lamprey (Petromyzon marinus) are native along the east coast of North America and the west coast of Europe. This species has experienced range-wide population declines in the past two centuries due to habitat loss and fragmentation resulting from widespread damming. The Penobscot River in Maine is emblematic of the influence of damming, as it has been heavily impounded by hydropower projects. However, in 2016 the Penobscot River Restoration Project (PRRP) completed the removal of two main-stem dams to improve habitat connectivity for this river’s 13 diadromous fishes. Now, a radio telemetry study is being conducted to assess the current status of Sea Lamprey in this watershed. In 2022, 87 returning adults were captured at Milford Dam (the first main-stem dam; river kilometer 62), transported downstream, and released after being surgically implanted with radio tags. Radio receivers have been placed along the Penobscot River’s main-stem and its major tributaries to track the movement of these fish through free-flowing reaches as well as around the remaining main-stem hydropower projects. Analysis of the resulting dataset will: 1) provide insight to Sea Lamprey passage efficiency at Milford and other dams, and 2) demonstrate how adult Sea Lampreys are distributing themselves in the Penobscot River watershed. Together, these data will provide an estimate of the River’s potential for Sea Lamprey restoration.
Corresponding Author: Cody Dillingham, 207-399-1194, [email protected]
Run to the sea: Atlantic Salmon smolt emigration timing variability in a changing climate
Danielle M. Frechette, Maine Department of Marine Resources, Bureau of Sea-Run Fisheries and Habitat, 121 State House Station, Augusta, Maine, 04333, USA. James P. Hawkes, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northeast Fisheries Science Center, 17 Godfrey Drive, Suite 1, Orono, Maine 04473, USA. John F. Kocik, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northeast Fisheries Science Center, 17 Godfrey Drive, Suite 1, Orono, Maine 04473, USA.
The Gulf of Maine Distinct Population Segment of Atlantic Salmon Salmo salar is listed endangered under the US Endangered Species Act. Recovery criteria center on maximizing the number of smolts, particularly those of natural rearing origin, entering the ocean. Because dams represent a substantial source of mortality for smolts – ensuring safe, timely, and efficient passage through dams is critical for recovery. We analyzed data from four long-term trapping
sites to characterize smolt emigration dynamics in Maine rivers. From these data, we developed a model to predict the onset of emigration and created a generalized smolt run (or wave) for natural-and hatchery-origin smolts in Maine rivers, which we used to: 1) simulate the movement of smolts in the Kennebec and Penobscot rivers to evaluate management actions, and 2) compare emigration timing between hatchery- and natural-origin smolts. Duration of the natural-origin smolt run was 42 to 58-d across trapping sites. Date of initiation varied by as much as two weeks among years and sites. Emigration dynamics differed between natural-origin and hatchery-origin smolts and our simulations indicated that emigration between the two rearing types was asynchronous. Our approach can be used to adaptively manage timing of protective measures at dams and improve synchrony between natural- and hatchery-origin smolts, thereby increasing in-river and marine survival. Importantly, we found the current 14-d spill windows are too short to consistently protect a large portion of the run or preserve adaptive variation in these populations and should be increased in the absence of other protective measures.
Stable isotope analysis of the nutrient pathways in the Medway River, Nova Scotia
Isabelle Génier, MSc Student , Leah Creaser, MSc Student , Trevor Avery .
 Department of Biology, Acadia University
 Departments of Biology and Mathematics & Statistics, Acadia University
Student author email: [email protected]
Southern Upland Atlantic salmon are assessed as endangered by COSEWIC. To aid in the recovery of the Medway River population the Medway River Salmon Association (MRSA) is working towards a smolt to adult supplementation program; growing Atlantic salmon smolts in sea cages and returning them to the river once they have reached spawning age. More data is required before proceeding, and so this project aims to gain a better understanding of the trophic interactions in the Medway River using stable isotope analysis (SIA). Carbon and nitrogen signatures reveal energy flow and trophic structure of the system. Carbon identifies the ultimate primary energy source because it remains relatively unchanged through the food chain, and nitrogen identifies the trophic position of organisms by becoming enriched as it moves up the food chain. Comparisons of isotopic values will show if there are changes in trophic structure throughout the year and if it differs between river sites. These isotopic values can also be used to compare the Medway River system to other SIA studies done on Atlantic salmon habitats. Using SIA values from systems that are known to have healthy Atlantic salmon populations can provide a healthy system baseline. Comparisons of the different river sites to this baseline would identify healthy sites. To the overall objective of the MRSA, my research will provide insight on how suitable the Medway River is for population recovery of Atlantic salmon based on stable isotopes.
Difficulty Breathing: Assessing changes in behavior and measures of vitality of American lobster at reduced oxygen levels. Robert Jarrett, Robert Steneck. University of Maine, School of Marine Sciences
The American lobster, Homarus americanus, recently shifted its habitat use; fewer lobsters are using shelter-providing boulder habitat where populations had historically been concentrated. More lobsters are now found on featureless habitats. Field sampling in boulder habitats found reduced oxygen levels inside the rocky shelters that lobsters had naturally preferred to occupy. Additionally, in recent years, hypoxic events in Cape Cod Bay led to lobster mortality in traps. Experiments assessing lobster shelter selection behavior showed no preference between shelters with ambient oxygen levels and with reduced oxygen levels. However, those trials were conducted over the course of several hours. It is possible that chronic effects of low oxygen could be creating a stressful environment for lobster in complex boulder habitats that may be changing their sheltering behavior. To address this, a longer experiment is being conducted, exposing lobsters to reduced oxygen levels over the course of 14 days. Movement, agonistic behavior, and vitality reflexes are quantified as metrics of stress throughout the trials. Preliminary results suggest lobsters chronically exposed to low oxygen exhibit orthokinesis in an attempt leave low oxygen habitats and could explain the observed shifts in habitat use and behavior.
Assessing the Distribution and Abundance of Bridle Shiners in Maine
Lara S. Katz – University of Maine, Dept. of Wildlife, Fisheries and Conservation Biology, Orono, ME
Stephen Coghlan, Jr. – University of Maine, Dept. of Wildlife, Fisheries and Conservation Biology, Orono, ME
Michael Kinnison – University of Maine, School of Biology and Ecology
Geneva York – University of Maine, Environmental DNA Laboratory
Joseph Zydlewski – U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit and University of Maine, Dept. of Wildlife, Fisheries and Conservation Biology, Orono, ME
Bridle shiners (Notropis bifrenatus) are one of Maine’s native species of freshwater minnow and are listed as a “Species of Special Concern” in the state. Bridle shiners have historically been found in southern and western Maine in densely vegetated, shallow habitats along the shorelines of streams and ponds. Bridle shiner populations have declined drastically across much of their native range, but their status in Maine is unknown. The goal of this project is to assess the status of this species and provide a foundation for future long-term monitoring in Maine. In 2021, we attempted to locate bridle shiners using a combination of both environmental DNA (eDNA) and traditional fisheries (seine net) surveys. We successfully located bridle shiners and/or bridle shiner DNA at 11 of 29 surveyed sites where these fish had historically been found. We measured habitat variables at all sites and used results from regression and occupancy analyses to build a GIS-based habitat suitability model. This model will be used to predict areas of suitable (and unsuitable) bridle shiner habitat in southern and western Maine. We are currently
conducting eDNA surveys of these water bodies to search for additional bridle shiner populations and to ground-truth our habitat model.
Response of Brook Trout Biomass to Strategic Wood Additions in the East Branch Nulhegan River Watershed, Vermont
Jud F. Kratzer
Vermont Fish and Wildlife Department, 374 Emerson Falls Road, Suite 4, St. Johnsbury, VT 05819, USA
Historic logging and log-driving have severely degraded fish habitat in many northeastern United States rivers, including the East Branch Nulhegan River, Vermont. To improve Brook Trout Salvelinus fontinalis habitat, 43 large woody material structures were constructed using chain saws and grip hoists in the East Branch and two of its tributaries. The purpose of this study was to assess the effects of these “strategic wood additions” on Brook Trout biomass. In the initial study, nine pairs of control and treatment sites were electrofished annually for two years prior to wood additions and four years afterward. By the second year of posttreatment sampling, average Brook Trout biomass at treatment sites had approximately tripled. In this presentation, I will provide an update on Brook Trout biomass at treatment and control sites nine years after strategic wood addition. The data will be collected in July, so I cannot yet summarize the results in this abstract. I predict that Brook Trout biomass in treatment sites will still be higher than before wood was added, but biomass will be lower than during the first four years post treatment due to deterioration of large wood structures.
Assessing Population Genetic Structure and Hatchery Introgression in Eastern Brook Trout in the Beebe River Watershed
Jared Lamy, Dr. Brigid O’Donnell, Dr. Amy Villamagna, Ben Nugent, Tyson Morrill, Joshua Hoekwater
Plymouth State University
In northern New England, stream fragmentation is most pervasive in the form of culverts at road crossings a result of decades of logging. The Beebe River watershed (Campton/Sandwich, NH) is an example of a system that has been impacted by historical land use practices. Access to ten kilometers of headwater habitat was blocked by four undersized culverts, preventing Eastern Brook Trout (Salvelinus fontinalis) from accessing valuable spawning habitat and thermal refugia, as well as isolating populations above crossings. In September of 2017, an extensive restoration project replaced the culverts with stringer bridges, reconnecting streams that had been fragmented for decades. This restoration presented a unique opportunity to examine Brook Trout population structure before and after restoration to develop an understanding of the success of the project in terms of its benefits to the persistence of Brook Trout. Prior to restoration in 2016, fin-clips (n=309) were collected via backpack electrofishing from throughout the watershed and genotyped at twelve microsatellite loci. Assignment analysis suggests populations above culverts belong to distinct genetic clusters. In contrast, results from non-fragmented tributaries suggest admixture is occurring where individuals are physically able to move throughout the watershed. Analysis of genotypes collected in 2018 (n=250) and 2019 (n=324) suggests minimal change in population structure post-restoration. In addition to assessing movement patterns, we also examined the degree to which introgression of hatchery genetics into wild populations has
occurred. Results suggest significant rates of hatchery introgression occurring throughout the study area, with the highest rates in streams that had fully passable crossings. Our study highlights the power of genetic analysis to answer questions pertinent to fisheries managers.
A Fine Kettle of Fish: Implications and Challenges of Aquatic Invasive Fish in Prince Edward Island.
Rosanne MacFarlane: PEI Department of Environment, Energy and Climate Action – Forests, Fish and Wildlife Division.
Species richness on Islands is generally lower than in mainland regions. Thus, it isn’t surprising that there are fewer freshwater fish in Prince Edward Island (PEI) rivers than in neighboring provinces. Brook trout and Atlantic salmon have been the dominant species in freshwater in PEI, however there has been a gradual change in the species composition in the past century. Rainbow trout, brown trout, golden shiners, red bellied dace, brown bullheads and more recently koi and goldfish have found their way to PEI, either intentionally or otherwise. Some of these fish have been embraced by the angling community while others are becoming a nuisance. And as biologists the world over have discovered, once aquatic invasive species establish themselves, they are virtually impossible to remove. This presentation looks at the change in fish species in Prince Edward Island, the implications of aquatic invasive fish on native fish species and their habitats, and the challenges involved in their management.
Water temperature and smolt size influence predation risk during reservoir migration
Matthew Mensinger, Department of Wildlife Fisheries and Conservation Biology, 5755 Nutting Hall, University of Maine, Orono, ME 04469, USA
Andrea Casey – School of Marine Sciences, 360 Aubert Hall, University of Maine, Orono, ME, 04469 – presenting Alessio Mortelliti – Department of Wildlife Fisheries and Conservation Biology, 5755 Nutting Hall, University of Maine, Orono, ME 04469, USA Joseph Zydlewski – U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit and Department of Wildlife Fisheries and Conservation Biology, 5755 Nutting Hall, University of Maine, Orono, ME 04469, USA
Fewer than two thousand adult Atlantic salmon (Salmo salar) return to Maine waters every spring, and the Gulf of Maine Distinct Population Segment is listed as Endangered under the ESA. The migratory smolt stage is the focus of considerable conservation effort for both wild and hatchery emigrants. Hatchery-reared smolts (650,000) are released into Maine waters annually to supplement low natural reproduction. More than a decade of acoustic telemetry in the heavily dammed Penobscot River has revealed high mortality of these stocked fish. Survival is especially low near hydropower complexes, and data suggest that predation in dam impoundments is a leading contributor to smolt loss. In spring 2022, we used Predation Event Recorders (PERs) to investigate smolt predation in the Weldon Dam reservoir. These devices directly record predation events on live fish tethered beneath a free-floating buoy equipped with a waterproof video camera. From April 23–May 24, we deployed PERs (n=398) within 5h of sunrise. After ~1h deployments, 21% (n=82) of smolts were attacked, and predator species consisted of chain pickerel (n=43), smallmouth bass (n=38), and one unidentified fish. Our
results suggest that high predation risk occurs during reservoir migration. The probability of predation was greater for smaller smolts, and risk of predation increased coincident with seasonal increases in water temperatures. Such information may inform stocking plans designed to maximize smolt survival through emigration into the marine environment.
Standardizing eDNA methods for monitoring estuary fish communities
Jeffrey T. Miller, Laura C. Crane Jason S. Goldstein, Christopher Peter, Alison W. Watts
University of New Hampshire
eDNA monitoring is becoming more common in fisheries assessment, and has great potential for standardized monitoring across a wide range aquatic environments. At the same time, the application and interpretation of eDNA results can be challenging. To better understand the strengths and limitations of eDNA tools for resource management and monitoring, we focused on standardizing sample collection methods and eDNA data analysis/interpretation for a large-scale collaboration across multiple estuarine reserve systems. To assess the viability of a standardized eDNA monitoring approach, we are collecting water samples in coordination with existing long term water quality and fish monitoring programs in 10 estuaries in the United States including Wells Maine and Great Bay NH. By applying the same sampling and analysis method at each location, we can directly compare our results to gain a better understanding of the practical use of eDNA monitoring in each site. Sampling is conducted quarterly at 4-5 sites in each region. We develop fish species lists, which are reviewed with site managers to determine if species are mis-identified, and if common species are missing. We seek to answer three questions posed by resource managers: How many species are detected by eDNA sampling in a given estuary? How does eDNA-based monitoring compare to traditional fish surveys? And what is the relative cost of these methods? We will present initial results including samples from May and August 2022, with a focus on results from our New England sites.
Cooler, Bigger; Warmer, Smaller±: Spatially Explicit Species and Size Stratification in
Behaviourally Thermoregulating Salmonids
Alexander M. Morgan1,2,3 and Antóin M. O’Sullivan*4,3,5
1Biology, University of New Brunswick (Fredericton, New Brunswick)
2Physics, University of New Brunswick (Fredericton, New Brunswick)
3Canadian Rivers Institute (Fredericton, New Brunswick)
4FOREM, University of New Brunswick (Fredericton, New Brunswick)
5O’Sullivan Ecohydraulics Inc. (Fredericton, New Brunswick)
*Corresponding authors: [email protected]
±Apologies to Daft Punk
Behavioural thermoregulation is a survival strategy widespread across the salmonid family, and occurs in response to an exceedance of stress inducing thresholds. Once these thresholds are exceeded salmonids seek regions of colder water, known as thermal refuges. During an extreme temperature event of summer 2021 a large aggregation of Atlantic salmon (Salmo salar – all age
classes) and brook trout (Salvelinus fontinalis – > 20 cm) was observed on the Little Southwest Miramichi River in New Brunswick, Canada when the main stem was ~31.5 °C. Using a drone-mounted thermal infrared (TIR) sensor, fine-scale TIR imagery of the occupied refuge was acquired. Polarized glasses were worn by an onshore observer to make visual observations at the site. Constructing maps from these data we examined the spatial distribution of fish, and the corresponding temperature of the areas they occupied. Salmonids were found to stratify by age class and species, with the stratification driven by the mosaic of temperatures in the refuge. Young of the year (YOY), 1+, 2+ and adult Atlantic salmon occupied areas with average temperatures ~ 30.1, 28.8, 25.7 and 21.9 °C, respectively; whilst mature brook trout occupied areas ~ 21.8 °C. Noteworthy is the observation of thermally aggregating young of the year Atlantic salmon, and the range in temperatures they occupied. One isolated, shallow, cold water patch (~22 °C) held YOY Atlantic salmon and no other age classes or species. Our findings highlight the importance of several different thermal characteristics of thermal refuges and their link to salmonid occupancy. Ultimately, these findings provide further insights to a growing repertoire of knowledge that can aid the design of ecologically meaningful thermal refuge augmentation/ restoration projects.
Beebe River Watershed L-TEME: A Ripple Across Regional Conservation
Tyson Morrill, Dr. Brigid O’Donnell, Dr. Amy Villamagna, Ben Nugent, Jared Lamy, Josh Hoewaker
Plymouth State University
Wild Brook Trout (Salvelinus fontinalis) populations have declined across much of their historic range, but strongholds persist across the northeastern US and Quebec province. However, the region includes degraded habitat conditions and barriers to movement from undersized or failing road crossings that continue to pose localized threats. The replacement of impassable road crossings and addition of wood are among the most common conservation actions taken to combat these threats. The Beebe River watershed (Campton/Sandwich, NH, USA) provides an informative case study in which five undersized road crossings were replaced to reconnect fragmented Brook Trout populations, and wood was added to headwater tributaries to recreate natural in-system processes. Long-term and fine-scale Brook Trout population and habitat monitoring included density, movement, growth, age structure, and genetic assessments, and results led to negotiations among stakeholders that shifted on-site riparian management and set a new precedent for conservation in NH. Perhaps the greatest positive outcome from these restoration actions has been the largely unanticipated collateral benefits that grew from the diverse suite of public (state and federal agency), private (non-profit and commercial), and academic partnerships. Engagement provided a springboard for long-lasting influences on the next generation of professionals, conservationists, and community members, resulting in a mosaic of opportunities and relationships across the region. We describe the events that led up to restoration, the restoration process, and the collaborative research, monitoring, and conservation partnerships that emerged, how those have fostered increased coldwater habitat conservation outside of the focal watershed, and highlight the broader-scale lessons learned along the way.
Investigating Whelk Bait Preference and a Future Shift to More Sustainable Baits for the
Channeled Whelk Fishery
Mary Kate Munley, Elizabeth Fairchild, Win Watson, Steven Jury, and Shelley Edmundson
Channeled whelk (Busycotypus canaliculatus) are fished along the eastern US coast with
baited traps, typically using parts of horseshoe crabs (Limulus polyphemus) as the predominant
attractant. As their blood is used extensively in biomedical research for vaccine development
horseshoe crabs are already heavily exploited. Additionally, they are the most expensive bait
ingredient. There is pressure to reduce horseshoe crab harvests therefore, the goal of this project
was to create an alternative bait, that is both cost effective and does not rely on horseshoe crabs.
The following individual baits were tested: 1) Horseshoe crab (both sexes); 2) green crab
(Carcinus maenas); 3) surf clam processing waste (Spisula solidissima); and 4) surf clam bellies,
as well as the following ingredients bound with an alginate binder: 1) diced green crab; 2)
Limulus hemolymph; 3) green crab-clam mix; and 4) surf clam bellies. Individual whelks were
placed in seawater tanks containing a bait bag with one of the aforementioned ingredients, and
whelk attraction to the bait was quantified over 24 hrs using time-lapse videos (n=149). Results
indicate that whelks were just as attracted to pieces of male horseshoe crabs as they were to
female horseshoe crabs and that the green crab-clam mix was as attractive as horseshoe crab
pieces. Furthermore, whelks interacted 27-38% more with the green crab-clam mixture than baits
containing only green crab, or only clam. These laboratory results indicate that alternative whelk
baits are viable replacements for horseshoe crab. Additional results from summer 2022
laboratory and field testing will be included.
Exploring differential expression of MHC related genes in Striped Bass (Morone saxatilis) in response to mercury contamination
Sam Nunn, Russell Easy
This project explores the differential expression of genes in the major histocompatibility complex (MHC) in striped bass in response to mercury contamination. Mercury is one of the most widespread, environmental contaminants on the planet. Methylmercury specifically bioaccumulates in aquatic environments due to retention in fat and inefficient excretion. Most organisms on the planet are chronically exposed to mercury and in humans primarily due to fish consumption. This has resulted in recommendations by many countries to limit consumption of fish to avoid mercury consumption. Striped bass are a large, anadromous fish that are important to Aboriginal, recreational and commercial fishers with roles in cultural activities. Striped bass require high quality food sources and specific conditions for egg laying, and thus can be used as indicators of ecosystem health. We will use RT-qPCR to explore changes in expression of target genes in striped bass as a result of mercury uptake. Striped bass tissue will be sent for mercury concentration analysis to compare the level of mercury concentration with gene expression. Genes of interest include onmy-DAA1, nRAMP and TGF-B, each playing an essential role in the MHC of striped bass. The goal of this project is to explore the effects of mercury on the expression of target genes in the MHC of striped bass.
The diadromous watershed-ocean continuum Valerie Ouellet1, Mathias J. Collins2, John F. Kocik3, Rory Saunders4, Timothy F. Sheehan5, Matthew B. Ogburn6, Tara Trinko Lake5 1Integrated Statistics contractor for NOAA Northeast Fisheries Science Center, Orono, ME; 2NOAA Restoration Center, Gloucester, MA; 3NOAA Northeast Fisheries Science Center, Orono, ME; 4NOAA Greater Atlantic Regional Fisheries Office, Protected Species Division, Orono, ME; 5NOAA Northeast Fisheries Science Center, Woods Hole, MA; 6Smithsonian Environmental Research Center, Edgewater, MD. Diadromous fishes play important ecological roles by delivering ecosystem services (fisheries, marine-derived nutrients, predatory interactions, etc.) and influencing ecosystem productivity. They also make crucial connections among ecosystems, including aerial and terrestrial. However, it is difficult to fully understand the community-level impacts and cumulative benefits of diadromous fish migrations, as these species are most often considered individually or in small groups. Their interactions at a community level (e.g., interdependencies such as predation, co-migration, habitat conditioning) and the connections between their ecosystem roles and functions (e.g., cumulative marine-derived nutrients contributions, impacts on stream geomorphology) are yet to be fully understood. Similarly, freshwater, estuarine and marine ecosystems are often considered independently, limiting understanding of the importance of connections across ecosystems. Not considering ecosystem interdependence and the importance of diadromous fishes as a community hinders the implementation of large-scale management necessary to increase ecosystem resilience and fish productivity across the range of these species. We developed a conceptual model, the Diadromous Watershed-Ocean Continuum (DWOC), that highlights how the diadromous community connects the different ecosystems they inhabit (marine, estuarine, and freshwater) and influence (terrestrial and aerial ecosystems) through migration, abundance, nutrient transfer, and other roles across a mosaic of habitats that includes headwater streams, lower rivers, and coastal streams as well as lakes, estuaries, nearshore, coastal shelf, and high sea habitats. Increasing the diversity and abundance of the diadromous community will increase the level of ecosystem services delivered throughout the community’s range and increase the community’s resilience to future changes. By recognizing the diadromous community ecosystem services landscape, DWOC can help promote a holistic approach to diadromous community management and provide a framework for discussions to identify research and management needs and support diadromous fish community ecosystem-based management.
The effects of fish size, stocking density, and photoperiod on juvenile lumpfish aggression Shelby A. Perry, Elizabeth A. Fairchild, Nathan B. Furey, and Brittany M. Jellison Department of Biological Sciences University of New Hampshire Durham, New Hampshire 03824 USA Atlantic Salmon (Salmo salar) is one of the leading species of marine finfish cultured in the U.S. However, Atlantic salmon reared in ocean farms, as well as steelhead trout (Onchorhynchus mykiss), incur a costly issue – sea lice, an ectoparasitic copepod. In order to combat sea lice, cleanerfish, fish that perform services for other fish such as the removal of ectoparasites and dead tissue, are used. Because lumpfish (Cyclopterus lumpus) are proven cleanerfish, resulting in a high demand for their use in salmonid ocean farms, increasing lumpfish hatchery production and rearing efficiency is of great importance to the aquaculture industry. As juveniles, lumpfish are cannibalistic which is controlled, to some extent, though frequent size grading of the fish, however, cannibalism still occurs. Understanding and mitigating for factors that exacerbate aggressive behaviors in juvenile lumpfish, that can lead to cannibalism, may aid in achieving the goal of increasing juvenile fish production in the hatchery. We hypothesize that lumpfish cannibalism is linked to a specific ontogenetic period related to fish size and can be exacerbated by various stressors such as stocking density and light intensity. To test this hypothesis, we subjected two different size classes of juvenile lumpfish (5g and 10g) to varying stocking densities (40g/L, 65g/L, or 90g/L) under different light intensities (ambient, constant low light, or constant bright light) for a 10-week duration in winter 2022. Fish growth, survival, and aggression were measured biweekly. Upon sampling, stocking densities were adjusted to baseline levels biweekly by removing any necessary fish. Final results, including daily growth rates, overall mean percent growth, survival, and occurrence and severity of fish aggression, as well as recommendations for lumpfish facilities, will be shared with session participants.
Environmental DNA as Surveillance Tool for Anadromous Fishes Upstream of the Mactaquac Generating Station Jacob Reicker, Philip Harrison†, Allen R. Curry†, Scott A. Pavey
Canadian Rivers Institute (CRI), University of New Brunswick, Saint John, Canada. †Canadian Rivers Institute, University of New Brunswick, Fredericton, Canada. River dams, such as the Mactaquac Generating Station (MGS) in Fredericton, New Brunswick, can impede migrations of anadromous fishes. This creates a necessity for intensive transporting programs to move fish upstream. Environmental DNA (eDNA) surveillance offers a non-invasive strategy for conservation and management of such aquatic species, without the need for costly traditional capturing methods (e.g. electrofishing). We will utilize current eDNA technology to monitor several important species – Atlantic salmon (Salmo salar), American shad (Alosa sapidissima), Alewife and Blueback herring (Alosa pseudoharengus and Alosa aestivalis, respectively; collectively known as River herring), Largemouth bass (Micropterus salmoides), and American eel (Anguilla rostrata) – as they migrate to their spawning sites in the summer and pass through the dam again in the fall. One-litre water samples (three 1L replicates per site) are presently being collected along the Saint John River and key tributaries between Fredericton and Perth-Andover, New Brunswick, from April to October 2022. The data will inform the Mactaquac Aquatic Ecosystem Study (MAES) on the habitat usage of the transported species.
Characteristics of small-scale fisheries off the coast of Salary, Madagascar and their impacts to a nearby Marine Protected Area Caitlin R. Shanahan, Dr. Elizabeth A. Fairchild, Dr. Easton R. White, Dr. Merrill Baker-Médard*
*University of New Hampshire, **Middlebury College
Marine Protected Areas (MPAs) are one of the management tools the International Union for the Conservation of Nature implements to preserve highly biodiverse and productive areas from harmful anthropogenic impacts, including overfishing. To further the understanding of small-scale fisheries and how they relate to MPA conservation goals, we examined fishing data collected from 2010 through 2021 from the MPA Soariake off of the coast of Salary, Madagascar. The data included 51 unique fishing locations over the 12-year period. To characterize the fisheries, we assessed the six most frequently visited fishing sites and analyzed spatial and temporal trends of the most frequently caught marine organism categories (Eel, Fish, Gastropod, Octopus, Sea Cucumbers, and Squid). We also investigated the types of gear used and for which marine organisms. We further analyzed temporally the two most frequently caught marine organism categories, Fish and Octopus, to investigate potential long-term impacts to their populations in the MPA Soariake. The results of this project provide an insight into the local fisheries and the conservation initiative of establishing MPAs in southwestern Madagascar.
Are smallmouth bass a major threat to juvenile Atlantic salmon in Maine? A habitat suitability model approach.
Rylee Smith: University of Maine, Dept. of Wildlife, Fisheries and Conservation Biology, Orono, ME
Joseph Zydlewski: U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit and University of Maine, Dept. of Wildlife, Fisheries and Conservation Biology, Orono, ME
Smallmouth bass is an introduced nonnative fish widespread throughout Maine waters. The species is known to compete and predate on juvenile salmon during freshwater rearing and seaward migration. The degree to which this influence is ecologically relevant, however, is poorly characterized. During freshwater rearing, spatial overlap between the two species is limited, suggesting either partitioning or exclusion from habitats. For competition or predation to exist, overlap in occupied space and/or overlap in a limiting resource needs to occur between species. Identifying the distribution of suitable habitat for each of the two species may inform the degree to which competition and predation are possible. We used habitat suitability assessment from the literature (e.g. depth, substrate, habitat type and temperature) to identify niche habitat characteristics and predict the theoretical distribution of juvenile Atlantic salmon and smallmouth bass. In conjunction with this, we are using historic electrofishing data (collected from Maine rivers from 1956-2020) to assess spatial and temporal overlap. Together, these data will be used to model the degree to which the presence of smallmouth bass may constrain the Atlantic salmon recovery under climate change scenarios.
Justin Stevens, Sea-Run Fish Ecosystem Program Coordinator Maine Sea Grant College Program The University of Maine
“[From the Estuaries Section Mission Statement] The Estuaries Section was established in 1994 as the primary bridge between the AFS and external organizations and individuals involved with estuarine research and management. We are dedicated to protecting, maintaining, and enhancing the viability of the fisheries and other aquatic living resources dependent upon healthy estuaries through the following goals: Advance the conservation, development, and wise use of fishery resources for the optimum use and enjoyment by all; Gather and disseminate information on fisheries science and management through forums and symposia; Promote and evaluate the educational, scientific, and technical aspects of the fisheries profession; Serve as a primary resource for developing public policy affecting estuarine fish and fisheries; Evaluate ongoing and proposed research and monitoring programs that address estuarine fishes in North America; and Support students and develop estuarine fisheries professionals.
In 2022-23 the Estuaries’ executive committee is committed to expanding participation in the section by actively recruiting from student and regional Chapters by sharing information about the Section’s scope and recent efforts.”
Climate-driven stock shifts and expansions in the U.S. Northeast Shelf: identifying challenges, opportunities, and barriers through fishermen and manager perspectives
Sophie A. Swetz – University of New England
Climate-driven warming in the U.S. Northeast Shelf (NES) has led to changes in the spatial distributions of many marine resources. Shifts and expansions of commercially important fish stocks pose major challenges to fishermen and fisheries managers in this region. American lobster (Homarus americanus) in the Gulf of Maine (GOM) is one of these impacted stocks and is projected to continue its shift towards more northern and offshore areas. Continued ocean warming could potentially reduce the GOM lobster stock by up to 60% over the next several decades. Given Maine’s reliance on its lobster fishery—which contributes over 80% of the value of Maine’s commercially harvested marine resources—building climate resilience into the fisheries social-ecological system is critical. Southern New England (SNE) serves as an example of a region that has already experienced much of the changes posed to impact the GOM. Through semi-structured interviews with SNE and GOM fishermen and a focus group of NES fisheries managers, black sea bass (Centropristis striata) was identified as a potential opportunity for fishermen to adapt to climate-driven changes. However, existing barriers—such as permitting, quota allocations, and bycatch regulations—prohibit the region’s fishermen from actualizing emerging opportunities. Results indicated that these barriers are not insurmountable and implementing “social-ecological management” approaches could provide viable pathways to facilitate opportunities and bolster climate resilience in the GOM.
Characterizing offshore lobster movement and distribution patterns within LFA 33 and 34 through a tagging program
Marco B. Turner1, Alysa Czenze, Trevor Avery2
1 Department of Biology, Acadia University, 2 Departments of Biology and Mathematics & Statistics, Acadia University
The lobster fishery is Canada’s most profitable fishery, with lobster exports valued at $3.26 billion in 2021. Profits are expected to continue because lobster landings continue to increase especially in the offshore, deep-sea fishery contingent. Lobster fishing areas (LFA) 33 and 34 are the largest and most profitable areas within Nova Scotia and include both inshore and offshore contingents. The primary goal is to characterize offshore lobster movements using a tag-recapture program. Lobsters were tagged using streamer tags and reported by fishermen after being caught during the fishing season. Data collected during the 2021-2022 fishing season will be presented. More data will be collected during the upcoming fishing season. Understanding lobster movement and distribution patterns is crucial to informing and stewarding the lobster fishery for the future. The study also aims to relate temperature, depth, and bottom type to lobster movements, describe the contingents (Alysa Czenze’s project focus), and describe by-catch (non-target fisheries effects). These relationships are described in other fishing areas that are generally inshore contingents. GIS mapping will show movement patterns and will be analyzed with respect to physical and environmental conditions. Analyses will characterize movement patterns and relate them to physical and environmental conditions and lobster morphometric data. It is expected that temperature will be a major factor in characterizing movement patterns because previous studies indicate warming waters increase suitable habitat within the offshore contingent. Overall, better offshore lobster information will inform conservation and management actions.
Collaboration networks within the CRU program
Sarah Vogel1 , Cynthia Loftin, Joseph Zylewski2,
1University of Maine, Ecology and Environmental Sciences, Orono, ME
Cynthia Loftin: U.S. Geological Survey, Cooperative Fish and Wildlife Research Units Program and University of Maine, Dept. of Wildlife, Fisheries and Conservation Biology, Orono, ME
Joseph Zydlewski: U.S. Geological Survey, Maine Cooperative Fish and Wildlife Research Unit and University of Maine, Dept. of Wildlife, Fisheries and Conservation Biology, Orono, ME
The U.S. Geological Survey’s (USGS) Cooperative Fish and Wildlife Research Units (CRU) program establishes relationships among the USGS, U.S. Fish and Wildlife Service, Wildlife Management Institute, host universities, and state resource agencies. It is a national network of individuals and organizations consisting of 41 Units in 39 states, each with broad administrative oversight and support provided by the program leadership. The mission of the CRU is to provide graduate education and facilitate research and technical assistance with cooperators. Since its inception in 1935, Units have conducted decades of wildlife and fisheries research and the program is well recognized for its contributions to management. These contributions have yet to be well quantified. This research focuses on analysis of CRU scientist outputs by: i) assessing the collaborative networks of the CRUs, and ii) quantifying the production of scientific publications. Collaboration networks have been compiled using co-authorship metrics at the individual, Unit, and CRU program levels. These networks identify connected “cliques” and research teams. They highlight patterns of information transfer, organizational structure, and may be predictive of scientist (and organizational) success. Co-authorship networks were highly varied, consisting of
a range of publication outputs; authors were predominantly affiliated with academia (i.e., scientists at universities, faculty, and graduate students). A common feature among CRU publications was a low ratio of multi-authored papers with the scientist as first author (i.e., low dominance factor). Often, graduate students assume first authorship reflecting graduate mentorship as a critical goal of the CRU program.
Lake Trout (Salvelinus namaycush) in Nova Scotia: A Historical Review and Development of a Habitat Suitability Model.
Matthew G. Warner1, Dr. Mike J.W. Stokesbury1, Dr. Sam Andrews1, Andrew Lowels2, John MacMillan2
1Acadia University, Department of Biology, Wolfville, Nova Scotia, 2Nova Scotia Department of Fisheries and Aquaculture: Inland Fisheries Division
Lake Trout (Salvelinus namaycush) are known to many anglers as the “grey ghost” of Nova Scotia. The province contains few suitable lakes for the species, and aquatic invasives coupled with hydroelectric development likely eliminated most ancestral populations. Extensive stocking efforts from 1886-1963 had no documented success but these efforts were sufficient to muddy the genetic waters of any ancestral population. The present distribution of Lake Trout in Nova Scotia is equally unknown. This history prompted the completion of an extensive historical review of Lake Trout in the Maritimes, including the provinces of Nova Scotia and New Brunswick. This review unearthed evidence of a sparse post-glacial distribution of Lake Trout in NS, prompting the implementation of a zero-retention limit on the species, and research to determine the reasoning of their decline, present distribution, and identification of native ancestry. To better describe suitable lake habitats in Nova Scotia, Lake Trout were tagged with pressure and temperature sensing acoustic tags in Sherbrooke Lake, one of the species’ last known refuges. The collected data will populate a model of annual depth and temperature residency to determine thermal habitat occupancy and habitat volume in summer when Lake Trout are most thermally restricted. This research is the first ever dedicated Lake Trout study in Nova Scotia. Information obtained will be the first step in understanding why Lake Trout declined in abundance and in what lake systems they can be recovered.
Key Words: Lake Trout, Nova Scotia, historical review, ancestral populations, stocking, suitable lake habitats, acoustic tags TITLE: Beyond species detection: using a novel environmental DNA method to monitor the genetics and abundance of an Atlantic Salmon population.
Beyond species detection: using a novel environmental DNA method to monitor the genetics and abundance of an Atlantic Salmon population
Jagger Watters-Gray1, Melissa K. Morrison1, Kurt M. Samways1, Scott A. Pavey1
1 Department of Biological Sciences, Canadian Rivers Institute, University of New Brunswick, Saint John, NB, Canada
Collecting environmental DNA (eDNA) has gained popularity as an easy to implement and non-invasive tool to detect the presence of freshwater fish species. However, extending eDNA surveying to monitor the genetics or abundance of fish populations has remained largely unexplored (population genetics) or is complicated by factors that influence eDNA concentrations in nature (population abundance). Investigating to what extent population-level
genetic information can be gathered from eDNA samples and how this information can be used to estimate fish abundance is an essential step to advance eDNA surveying. This project’s objective is to develop a novel eDNA method to monitor the genetics and abundance of an Atlantic Salmon population in New Brunswick, Canada. We’ve been conducting two eDNA surveys across different spatial and temporal scales in two rivers with known Atlantic Salmon genetics and abundance. Using a panel of microsatellite loci, our first survey aims to assess the congruence between eDNA-based population allele frequencies and tissue-based allele frequencies of juvenile Atlantic Salmon during the summer as several monitored environmental variables fluctuate throughout the season, but the genetics and abundance of the population remains constant. Our second survey aims to test if eDNA-based population allele frequencies and the number of unique alleles in an eDNA sample can estimate Atlantic Salmon abundance during their smolt migration. Samples have been collected over two years during smolt migration near a rotary screw trap with a known capture efficiency. We will determine eDNA-based microsatellite allele frequencies and the number of unique alleles in the eDNA samples and use this information in a likelihood-based DNA mixture framework to estimate the number of unique genetic contributors to the eDNA samples. We expect this novel approach has the potential to extend eDNA surveying beyond species detection to characterize population-level genetic diversity and absolute abundance of Atlantic Salmon.