Nature-like fish passes have been designed with the intent to re-connect river corridors and provide passage for all species occurring in a system. Nature-like fish pass designs have been constructed in Europe and elsewhere with some success, but performance of these designs has not been evaluated for North American species. Re-establishing passage for adult anadromous clupeids to their spawning areas is critical considering their recent dramatic population declines. Two nature-like fish pass designs in New England were evaluated for passage of anadromous adult alewives (Alosa pseudoharengus) using passive integrated transponder (PIT) telemetry and showed differing results. At Town Brook in Plymouth, Massachusetts the 32 m long perturbation boulder rock ramp with a 1:24 slope passed 94% of attempting fish with most ascending in under 22 minutes. At East River in Guilford, Connecticut the 48 m long steppool bypass design with a 1:14 slope passed only 40% of attempting fish with a median transit time of 75 minutes. Two technical fishway designs at the field sites were also evaluated and showed contrasting performance. At Town Brook a 14 m long 1:7 slope pool and weir fishway exhibited attraction and passage deficiencies. At East River two 3.05 m long steeppass fishways both passed the majority of attempting fish but one steeppass fishway may have had poor attraction efficiency. At both sites tagged fish passed rapidly downstream through the fish passes after spawning. Nature like fish pass designs are suitable for the passage of alewife but further evaluations are required to more precisely identify the influence of vertical drop per pool and specific local hydraulics on behaviors and passage performance for this species.

Pacific lamprey (Entosphenus tridentatus) is an endemic species to coastal watersheds along the Pacific Rim in North America and Asia. The species' geographic distribution is retracting and has not been mapped precisely, and the ability for the species to provide ecosystem services, such as water filtration, for supporting watershed management has not been tested. The San Luis Obispo Creek watershed, California, USA is at the southern end of Pacific lamprey’s retracting distribution, and the San Luis Obispo watershed is impacted by degraded water quality, making investigation of Pacific lamprey in the San Luis Obispo Creek watershed of direct local conservation importance. This thesis is presented as two manuscripts formatted for submission to scientific journals. The first manuscript features a study that estimates Pacific lamprey presence/absence throughout the San Luis Obispo Creek watershed using Environmental DNA. We compare our estimate to previous estimates of Pacific lamprey population distribution using established eFishing and redd survey methods. We found our estimate of distribution based on Environmental DNA to match the previous estimates throughout San Luis Obispo Creek, as well as indicate a location with Pacific lamprey presence that was previously unsurveyed. In this manuscript, we also discuss advantages and disadvantages to using Environmental DNA as a cost-effective and non-invasive method to survey Pacific lamprey in the wild. The second manuscript is a laboratory study focused on the larval (ammocoete) stage of Pacific lamprey. We tested the ability for an ammocoete population to reduce the concentration of harmful bacteria in water through filter-feeding. We found an increased decline of bacteria in experimental aquaria treated with ammocoetes than in control tanks or tanks containing non-filter feeding Pacific lamprey, indicating that ammocoetes can indeed significantly reduce bacterial loads in a contained environment. The laboratory study was conducted using water from San Luis Obispo Creek that was naturally inoculated with bacteria, generating broader applicability of the study in suggesting that Pacific lamprey have the potential to provide a water filtration ecosystem service in the wild for supporting high water quality watershed management objectives. These two studies contribute to knowledge on how to efficiently survey Pacific lamprey distribution in the wild and benefits the species may provide to ecosystems and human welfare. Collectively, they help us better understand the status and value of this often-forsaken anadromous species.

Thesis (M.E.S.)--The Evergreen State College, 2007. / Title from title screen viewed (4/7/2008). Includes bibliographical references (leaves 49-56).

Seasonal movements of anadromous brook trout (Salvelinus fontinalis) were studied in riviere au Saumon, James Bay, during 1986 to 1988. A comparison of the biology and energetic parameters between sea run and freshwater brook trout was made in the same system. Anadromous brook trout started their downstream movements in May and displacements peaked in June, but some also occurred in fall. Downstream movements were correlated with spring and fall freshets. Important interannual variation was observed in the movement pattern. Seaward movements of anadromous trout were limited to the brackish waters, as fish congregated at the river mouth. I suggest that movements into brackish waters are passive. Upstream movements began in late July and continued until freezing (November), with the intensity of movement varying annually according to climatic conditions. / Comparison between anadromous and freshwater trout showed very little difference in mean length at age, age at maturity, egg size and fecundity between the two groups. However, examination of energetic parameters indicated that sea run brook trout had a greater increase in condition factor during the summer than the freshwater residents. This raise in condition factor is accompanied by a decrease in water content and a lower water content in the eggs of anadromous fish. These results indicate that benefits associated with anadromous migrations in brook trout reside in the seasonal pattern of energy storage, which is important for the recovery from energy expenditure associated with spawning and overwintering.

Conserving and restoring anadromous fish populations is an important research and management priority. For conservation to be effective, researchers must understand the behavior of the fish they seek to restore. Telemetry has allowed researchers to understand the upstream migrations of these fish in freshwater, how migration patterns vary, and if there is a relationship between behavior and environmental variables. In the northeastern United States, alewife (Alosa pseudoharengus), one of two species collectively referred to as river herring, has historically been an important component of coastal rivers. However, populations of these fish have experienced recent declines, and a commonly used method to restore river herring is stocking. In this thesis, I summarize research that seeks to understand anadromous alewife behavior with the goal of providing insights that will help manage and conserve this species and the coastal systems in which they live. My thesis has a primary research chapter (Chapter 1), a second ancillary research chapter (Chapter 2), and four appendices that summarize related information as part of the funding proposal. First, to examine if fish origin (native or stocked) and fish release location (upstream or downstream) affected the pre-spawning movements of fecund alewives, I undertook a reciprocal experiment. In Chapter 1, for fish of both origins and release locations, I examined how long fish were in the river, where they spent their time, and how much and how fast they moved. For this, I gastrically tagged alewives with Lotek Nanotags NTC-6-1 radio tags and monitored movements in the lower 30 km of the Ipswich River (northeastern Massachusetts) using an array of 9 Lotek SRX_400 receivers. Based on these movement trajectories I concluded that in 2007, origin affected the total time fish spend in the river and release location affected where they spend their time. Downstream movements of upstream migrating fish have typically been viewed as a behavioral assay of adverse tag effects. For this reason, alosine telemetry studies rarely release tagged fish upstream of the capture site. However, fisheries managers often release fish upstream near spawning grounds during stocking. In Chapter 2, I re-evaluated whether downstream movements of upstream stocked fish were consistent with an adverse tag effect. By combining physiological experiments with select movement trajectories, I showed that pre-spawning migrations of alewife included an array of up and downstream directed movements with various interpretations. In my research, these downstream movements were unlikely to be related to tagging stress (Chapter 2), as the cortisol, glucose, and chlorides of tagged fish were not different from untagged fish (Appendix A, Physiology). Furthermore, I suggested metrics that should be recorded in telemetry studies to standardize how downstream fish movements are measured. In 2006, native fish were released at a downstream site (river km 6) and stocked fish were released upstream (rkm 25). I compared the behaviors of these same treatments across years. I showed that the behaviors of fish released in different years may differ based on temperature and discharge (Appendix B, Across Year Comparison). To determine the amount and location of potential spawning habitat, I undertook a habitat study that utilized a geographic information system (GIS) to maps the size and distribution of habitat types. I located multiple mainstem pools in the Ipswich River that may serve as suitable spawning grounds for alewife. Tagged fish were primarily located in these habitats (Appendix C, Habitat). To determine if juveniles were produced, I sampled various sites in the river for the presence of juveniles, using active and passive sampling techniques. Juveniles were not captured during these surveys (Appendix D, Juvenile Sampling). Before this research, little was known about the pre-spawning migrations of river herring. While river herring are assumed to be a generalist species, I found their behaviors to be complex. I have identified a number of gaps in the current knowledge of how these fish behave in the field. Restoration efforts must take into account the behavior of the fish, as well as the capacity of a system to accommodate those needs. Within the context of understanding fish behavior, protecting habitat, and providing regulatory restrictions on the fishery, stocking may contribute to broader management and restoration goals.

Over the last century anadromous alewife (Alosa psuedoharengus) and blueback herring (Alosa aestivalis), collectively called river herring, suffered drastic declines throughout their range from Newfoundland (Canada) to North Carolina (USA). A 2011 petition to include river herring in the Endangered Species Act (ESA) was rejected, partly due to inadequate information towards identifying coast-wide population status. Additionally, knowledge gaps were identified with basic ecology of the river herring life cycle in freshwater, including species reproductive strategies. In Chapter 2, I investigated how body size, spawning arrival time, and sex influence river herring reproductive success. I collaborated with the Massachusetts Division of Marine Fisheries to introduce adult river herring (421, 266, and 410 individuals in 2013, 2014, and 2015, respectively) into Pentucket Pond (Massachusetts, USA), which historically had river herring but is currently inaccessible to upstream migrants. Using fin clips from stocked adult fish and juveniles collected in the lake each summer, I genotyped individuals and constructed pedigrees with 15 microsatellites. River herring had small (mean =1.1) families and spawned multiple times with multiple mates from May to June. Females were more successful than males. Earlier arrival and larger body size were independent indicators of reproductive success. These results provide critical river herring life history information for the freshwater component of population models that will inform management of this at-risk species. Presently, most river herring populations are monitored using data from citizen counts of spawning adults entering freshwater. Involving citizen watershed groups in data collection and may provide ancillary benefits beyond collection of population-level count data. In Chapter 3, I used pre-and post-surveys to assess how involvement in one citizen monitoring program influenced participants’ environmental knowledge, attitudes, and behaviors. Participants began the program with high scores for broader scientific and pro-environmental attitudes and pro-environmental behaviors. After the program, participants reported increased connection to nature, citizen science involvement, river herring knowledge, and engagement in outdoor recreation. For participants, engagement with nature was the most important program benefit. These results provide an additional case study to the citizen science literature and demonstrate that citizen science programs can help participants connect with the environment.

No description available.

Accurate smoltification and disease management in Atlantic salmon (Salmo salar) are key issues for the aquaculture industry. Due to their anadromous lifecycle the transfer of salmon from fresh water (FW) to seawater (SW) is crucial to their survival; too early can cause mortality, too late can cause desmoltification and long-term health problems. Both scenarios can increase susceptibility to four viral diseases: Salmon alphavirus (SAV), Infectious salmon anemia virus (ISAV), orthoreovirus (PRV), and Piscine myocarditis virus (PMCV). They all show similar clinical and histopathological symptoms and can easily spread throughout farms. Understanding the initial innate immune response to these viruses may provide biomarkers that could help identify and monitor infections. An in house and onsite Na+/K+ ATPase (NKA) qRT-PCR assay was developed for the salmon biomarker ATPase to test smoltification readiness in salmon smolts. Tested against NKA enzymatic assays it showed a similar success rate over 3 years: NKA qRT-PCR (57%), NKA activity assay (60%). Onsite tests confirmed that the ATPase mRNA transcript is a useful biomarker for smoltification detection. An in-lab and mobile multiplex qRT-PCR assay was developed for detection of SAV, PRV and PMCV. The analytical sensitivity of the SAV (86.5% SE 0.11), PRV (90.94%, SE 0.09) and PMCV (100.46%, SE 0.19) assays was 102 copies for PMCV and 103 for SAV and PRV. Initial results suggest individual assays could be run on site at farms. Addition of an internal control, probit analysis and viral positive tests are still required for multiplex assay integration. Salmon erythrocytes were infected with ISAV, SAV and Poly I:C to investigate whether they induce and up-regulate innate immune response genes. All genes were expressed at low levels in all parameters investigated including non-infected control erythrocytes. These findings suggest erythrocytes act as an initial buffer to viral infections and may help stimulate the innate immune response.

The seasonal and diel feeding habits of the goosander, Mergus merganser, the red-breasted merganser, M. serrator, gulls (Larus canus, L. argentatus and L. fuscusj and terns, Sterna hirundo/paradisaea were studied at 64V05'N. Birds' activity patterns were influenced by the nocturnal spawning of the river lamprey (Lampetra fluviatilis). Food selection and food consumption by hand-raised mergansers together with aquarium studies of the diel activity patterns of their most important prey supplemented the field data. River lamprey dominated the diet of the goosander by weight and the sculpin Cottus gobio by number. The fish consumption of the goosanders was found to be about 12% of the available river lamprey biomass and about 17% of the sculpin biomass during the breeding season. In experimental situations the river lamprey was a low- pritority species compared with salmon , Salmo salar, brown trout, 53. trutta, and minnow, Phoxinus phoxinus, when presented to satiated birds of both Mergus species. When hungry, however, the birds caught the available prey irrespective of species, but they selected larger prey when two size classes were present. Experimental results were compared with field data on availability, consumption and the escape behaviour of the various fish species. The rivers emptying in the Bothnian Bay are regarded as important feeding areas for birds breeding along the coast. In early spring they get access to abundant and reliable food resources, e.g the river lamprey. Later on the three-spined stickleback, Gasterosteus aculeatus, supply both Mergus species with food in the river and also along the coast. From the middle of June potential food supply available to birds decreases in the rivers and becomes more abundant in the coastal area. / <p>S. 1-41: sammanfattning, s. 43-227: 7 uppsatser</p> / digitalisering@umu

Migration occurs among many animal species for the purpose of, among other things, finding food or to reproduce. Spawning migration is a form of migration that occurs among many fish species where they move to another site for reproduction. The movement can be obstructed by migration barriers like road culverts. Barriers to migration pose one of the greatest threats to biodiversity and ecosystem functions in freshwater. They impair the connectivity of watercourses and may prevent fish from improving reproductive success or completing their life histories altogether. There are both benefits and costs with migration, benefits such as increased survival for the adults and offspring, and costs such as increased energy consumption and increased mortality. The costs are often dependent on the morphological traits of the individual, like body shape and size. In this study, the spawning migration of two species of fish of the family Cyprinidae, ide (Leuciscus idus) and roach (Rutilus rutilus) was investigated. Few studies have been made on ide or on roach compared to other cyprinids and salmonids. This study might therefore enhance the overall knowledge of these two species. The overall aims of this project are to study and compare phenotypic correlates of spawning migration behaviour of ide and roach. The field studies were performed in Oknebäcken, Mönsterås (SE632310-152985), Sweden in March and April 2020. To describe the watercourse and define the location and characteristics of different potential migration barriers, a simplified biotope mapping method was used. The fish were caught in a hoop net and then measured, weighted, sexed, and injected with passive integrated transponder using the bevel down method. In order to register in stream movement of fish, reading stations with antennas were placed, at two locations upstream from the marking station and one downstream at the estuary. The sex ratio differed from the expected 1:1 with a majority of females for both species. This might be a result of fluctuations in survival of spawn coupled with different age-at-maturity between sexes. We found that individuals that arrived early to the stream were larger for both study species, as other studies also reported. Also, male ide was both larger and arrived before female ide. There might be an energy cost associated with early arrival to the stream and therefore, larger individuals arrive first. For roach, there was no difference in arrival time between the sexes although female roach were larger. There was no difference in the time spent in the stream between the species. For ide, females stayed for a longer period of time in the stream than males. However, the opposite was true for roach. This may be because male roach might benefit from more fertilization events when staying longer. There might therefore be a trade-off between the energy cost in staying in the stream and the increased fitness advantage in fertilization events. We found no correlation between any of the morphological traits and migration distance. However, since very few individuals were registered at the upstream reading stations, there might be an effect of migration barriers on the spawning migration. The mortality after spawning was higher for roach than for ide. For ide, a larger proportion of females than males died. For roach, individuals that arrived early was classified as alive to a greater extent than those who arrived late. Both similarities and differences between the species were discovered in this study which concludes that even closely related species might differ substantially from each other.