Download or read book Modeling Spawning Habitat Potential for Chum Oncorhynchus Keta and Pink Salmon O Gorbuscha in Relation to Landscape Characteristics in Coastal Southeast Alaska written by and published by . This book was released on 2018 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: In response to the increasing need for ecosystem services throughout the Southeast Alaska region, decision makers are tasked with balancing the need for natural resources with salmon conservation. However, accurate historical and current information on salmonid population abundance, freshwater distribution, and habitat quality are sparse with limited resolution for large portions of this remote and rugged landscape. Here, I created Intrinsic Potential (IP) models for chum and pink salmon to predict the potential for portions of coastal rivers to provide high-quality spawning habitat. I developed IP models for both species from field redd surveys and synthetic habitat variables derived from 1-m resolution digital elevation models. The surveys were performed at 49 study reaches in five coastal drainage basins on the north end of Chichagof Island, Southeast Alaska.

Download or read book River Features Associated with Chum Salmon Spawning Areas written by John Patrick O'Brien and published by . This book was released on 2006 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Diminishing returns of salmon and years of poor commercial and subsistence fishing in western Alaska are a cause for concern. Management tools which recognize the intricate life histories of salmon and incorporate environmental conditions at each particular life stage are needed. Toward that goal a study of spawning habitat for chum salmon Oncorhynchus keta was conducted from 2002 to 2005 on the Tuluksak River in western Alaska. Small-scale river features were measured during two summers of field work. Large-scale river features were identified using remote sensing. Principal components analysis (PCA) denoted an association between spawning sites and channel intersections, gravel bars, islands, and areas of accelerated channel change, forming the basis for a predictive habitat model. Two models were developed that combined them habitat assessment with chum salmon redd size and spatial requirements at three spawning densities. The first model, based on field observations in 2002 and 2003, estimated a greater spawning capacity than the second model, based on large-scale river features. Spawning capacity estimates from both models were consistent with historic escapement data and should be used as a starting point for further research. This study represents progress toward a management strategy that is sensitive to habitat-dependent production potential"--Leaf iii.

Download or read book Nutrient Enrichment Trophic Exchanges and Feedback Loops written by Michelle Catherine Nelson and published by . This book was released on 2014 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: The movement of nutrients across ecosystem boundaries can affect recipient ecosystems at individual, population, and community levels. This is particularly the case when more productive systems subsidize less productive ones, where subsidies can sustain and enhance populations in nutrient-poor recipient environments. One prominent example of this is the annual migration of salmon from the marine environment into low-productivity freshwater streams for spawning. This thesis uses data collected from 47 near-pristine streams on the central coast of British Columbia to study spawning chum (Oncorhynchus keta) and pink (O. gorbuscha) salmon and the ecological implications of their nutrient subsidy, focusing on stream-rearing juvenile coho salmon (O. kisutch). While considering a broad suite of habitat characteristics, the strongest predictors of juvenile coho size and abundance were spawning chum and pink salmon abundance. Streams with more spawning chum salmon had larger coho, while streams with more spawning pink salmon had higher coho populations. Further, the evidence suggested the negative association between juvenile coho and their intraguild predators/competitors, sculpin (Cottus aleuticus and C. asper), may be reduced as more spawning salmon nutrients became available. Altogether, this thesis shows strong impacts of marine-derived nutrient subsidies to freshwater ecosystems at multiple ecological scales. In general, it provides insights into the ecological mechanisms by which species interact with their environments, the potential for nutrient subsidies to affect recipient populations through changing food supply and predator-prey dynamics, and the role of multi-trophic interactions in subsidized trophic cascades. In specific, this research improves our understanding of the potential positive feedback between different species of salmon while incorporating the importance of multiple habitat characteristics. This has the potential to inform conservation and ecosystem-based management, particularly in light of the drastic decline in spawning salmon abundance in northern Pacific regions.

Download or read book Using Remote Sensing Occupancy Estimation and Fine scale Habitat Characterization to Evaluate Fall Chum Salmon Oncorhynchus Keta Spawning Habitat Usage in Arctic Alaska written by Chelsea M. Clawson and published by . This book was released on 2017 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Groundwater upwellings provide stable temperatures for overwinter salmon embryo development and this process may be particularly important in cold, braided, gravel-bed Arctic rivers where rivers may freeze solid in the absence of upwellings. Aerial counts and remote sensing were used during 2013-2015 to estimate fall chum salmon (Oncorhynchus keta) spawner abundance states (e.g., low or high), classify river segments by geomorphic channel type (primary, flood, and spring), and map thermal variability along a 25.4 km stretch of the Chandalar River in interior Alaska. Additionally, I used on-the-ground examination of fine scale variation in physical habitat characteristics at 11 representative sites to characterize habitat variability, placed temperature loggers to assess overwinter thermal conditions in redds, and used a developmental model to predict hatching and emergence timing given known spawning dates and incubation temperatures. I delineated 330 unique river segments (mean length = 536 m) and used a multi-season multistate occupancy model to estimate detectability, occupancy, and local colonization and extinction rates. Triplicate surveys performed in 2014 allowed me to estimate detectability and the influence of observer bias. I found that detectability did not vary by observer, channel type, or segment length, but was better for high abundance (0.717 ± 0.06 SE) relative to low abundance (0.367 ± 0.07 SE) aggregations. After correcting for imperfect detection, the proportion of segments occupied by spawning fall chum salmon was highest in 2014 (0.41 ± 0.04 SE), relative to 2013 (0.23 ± 0.04) and 2015 (0.23 ± 0.04). Transition probabilities indicated unoccupied segments were likely to remain so from year to year (2013→2014 = 0.67; 2014→2015 = 0.90), but low abundance spawning segments were dynamic and rarely remained in that state. One-third of high abundance sites remained so, indicating the presence of high quality spawning habitat. Mean segment temperatures ranged from -0.5 to 4.4°C, and occupancy varied positively with temperature. I predicted a 50% probability of occupancy in segments with temperatures of 3°C. With my on-the-ground work, I found that habitat characteristics varied among the three channel types, with most significant differences between main channel and off-channel habitats. Dissolved oxygen and pH decreased with increasing temperature, and conductivity increased with temperature. Predicted hatching and emergence timing ranged from 78 and 176 days (December 11th and March 18th) to 288 and 317 days (July 8th and August 6th), respectively, post-spawning, and were highly variable within sites and among channel types owing to high habitat thermal heterogeneity. Because the Chandalar River supports 30% of the fall chum salmon run in the Yukon River Basin, information such as provided by this study will be critical to allow resource managers to better understand the effects of future climate and anthropogenic change in the region.

Download or read book A Remote Sensing GIS Based Approach to Identify and Model Spawning Habitat for Fall Chum Salmon in a Sub arctic Glacially fed River written by Lisa M. South and published by . This book was released on 2010 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: "At northern extremes, fish habitat requirements are often linked to thermal preferences and the presence of overwintering habitat. The goal of this study was to identify spawning habitat for fall chum salmon Oncorhynchus keta and model habitat selection from spatial distributions of tagged individuals in the mainstem Tanana River, Alaska. I hypothesized that the presence of groundwater, which provides thermal refugia for overwinter incubation, would be most important for fall chum salmon. Models included braiding, sinuosity, open water surface area (indicating significant groundwater influence), and open water persistence (consistent presence of open water for a 12 year period according to satellite imagery). Candidate models containing open water persistence were selected as most likely. Persistent open water areas were further examined using forward-looking infrared (FLIR) imagery; marked differences between sites were observed in the extent of thermal influence by groundwater. Persistent open water sites with strong groundwater influence appear to serve as core areas for spawning salmon; the importance of stability through time suggests the legacy of successful reproductive effort in these areas for this homing species. This study indicates that not only the presence of groundwater is important for spawning chum, but its persistence and extent of groundwater influence"--Leaf iii.

Download or read book Characteristics of Fall Chum Salmon Spawning Habitat on a Mainstem River in Interior Alaska written by Sean Eugene Burril and published by . This book was released on 2010 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Predicting Spawning Habitat for Coho Salmon Oncorhynchus Kisutch Chinook Salmon Oncorhynchus Tshawytscha and Steelhead Oncorhynchus Mykiss Using Geospatially Constructed Stream Morphology from High resolution Lidar derived Digital Elevation Model and Field Survey Data in the Indian Creek Watershed Mendocino County California written by Justin P. Bissell and published by . This book was released on 2019 with total page 209 pages. Available in PDF, EPUB and Kindle. Book excerpt: Restoration of anadromous salmonid habitat is of primary importance to the economic, historical, and cultural geography of the Pacific Northwest. Derivation and use of geospatial habitat models as guides to pinpoint key areas where limited restoration funding can be cost-effectively employed is of great importance. To this purpose, 1 meter resolution lidar-derived Digital Elevation Model data was acquired for the Indian Creek and neighboring watersheds in Mendocino County, California, and used together with field-acquired geomorphic stream data to geospatially model stream widths, depths, and streambank morphology. These geospatial covariates were field-verified in selected locations and then used in conjunction with field surveyed habitat presence data and substrate data to model potential anadromous salmonid species spawning habitat. Probability surfaces, each comprising the areal extent of the Indian Creek stream system and representing the probability for spawning habitat occurrence, were developed for each of the species of interest. The mean area under the curve (AUC) for 100 model replications for Chinook, Coho, and Steelhead were 0.954, 0.951, and 0.958, with standard deviations of 0.036, 0.034, and 0.036, respectively. In contrast to other models that solely use linear lengths of stream, the models developed in this work incorporate modeled stream bankfull widths and modeled stream corridor morphology, thus allowing additional interpretation and prediction involving the amount of species' use of specific streams and watersheds. Models were field-verified by California Department of Fish and Wildlife fisheries biologist staff and Pacific Watershed Associates engineering geologists and field scientist staff as being representative of actual field conditions, thus assuring the value of modeling results and methodology in future projects and research.

Download or read book Freshwater Habitat Model written by Alaska. Department of Fish and Game. Habitat Protective Section. Resource Assessment Branch and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Challenges for Diadromous Fishes in a Dynamic Global Environment written by Alex Haro and published by . This book was released on 2009 with total page 976 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sponsored by the Northeastern Division, American Fisheries Society.

Download or read book Effect of Quality of the Spawning Bed on Growth and Development of Pink Salmon Embryos and Alevins written by Ralph A. Wells and published by . This book was released on 1970 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spawning Habitat Studies of Hanford Reach Fall Chinook Salmon Oncorhynchus Tshawytscha Final Report written by and published by . This book was released on 2009 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pacific Northwest National Laboratory conducted this study for the Bonneville Power Administration (BPA) with funding provided through the Northwest Power and Conservation Council(a) and the BPA Fish and Wildlife Program. The study was conducted in the Hanford Reach of the Columbia River. The goal of study was to determine the physical habitat factors necessary to define the redd capacity of fall Chinook salmon that spawn in large mainstem rivers like the Hanford Reach and Snake River. The study was originally commissioned in FY 1994 and then recommissioned in FY 2000 through the Fish and Wildlife Program rolling review of the Columbia River Basin projects. The work described in this report covers the period from 1994 through 2004; however, the majority of the information comes from the last four years of the study (2000 through 2004). Results from the work conducted from 1994 to 2000 were covered in an earlier report. More than any other stock of Pacific salmon, fall Chinook salmon (Oncorhynchus tshawytscha) have suffered severe impacts from the hydroelectric development in the Columbia River Basin. Fall Chinook salmon rely heavily on mainstem habitats for all phases of their life cycle, and mainstem hydroelectric dams have inundated or blocked areas that were historically used for spawning and rearing. The natural flow pattern that existed in the historic period has been altered by the dams, which in turn have affected the physical and biological template upon which fall Chinook salmon depend upon for successful reproduction. Operation of the dams to produce power to meet short-term needs in electricity (termed power peaking) produces unnatural fluctuations in flow over a 24-hour cycle. These flow fluctuations alter the physical habitat and disrupt the cues that salmon use to select spawning sites, as well as strand fish in near-shore habitat that becomes dewatered. The quality of spawning gravels has been affected by dam construction, flood protection, and agricultural and industrial development. In some cases, the riverbed is armored such that it is more difficult for spawners to move, while in other cases the intrusion of fine sediment into spawning gravels has reduced water flow to sensitive eggs and young fry. Recovery of fall Chinook salmon populations may involve habitat restoration through such actions as dam removal and reservoir drawdown. In addition, habitat protection will be accomplished through set-asides of existing high-quality habitat. A key component to evaluating these actions is quantifying the salmon spawning habitat potential of a given river reach so that realistic recovery goals for salmon abundance can be developed. Quantifying salmon spawning habitat potential requires an understanding of the spawning behavior of Chinook salmon, as well as an understanding of the physical habitat where these fish spawn. Increasingly, fish biologists are recognizing that assessing the physical habitat of riverine systems where salmon spawn goes beyond measuring microhabitat like water depth, velocity, and substrate size. Geomorphic features of the river measured over a range of spatial scales set up the physical template upon which the microhabitat develops, and successful assessments of spawning habitat potential incorporate these geomorphic features. We had three primary objectives for this study. The first objective was to determine the relationship between physical habitats at different spatial scales and fall Chinook salmon spawning locations. The second objective was to estimate the fall Chinook salmon redd capacity for the Reach. The third objective was to suggest a protocol for determining preferable spawning reaches of fall Chinook salmon. To ensure that we collected physical data within habitat that was representative of the full range of potential spawning habitat, the study area was stratified based on geomorphic features of the river using a two-dimensional river channel index that classified the river cross section into one of four shapes based on channel symmetry, depth, and width. We found that this river channel classification system was a good predictor at the scale of a river reach ((almost equal to)1 km) of where fall Chinook salmon would spawn. Using this two-dimensional river channel index, we selected study areas that were representative of the geomorphic classes. A total of nine study sites distributed throughout the middle 27 km of the Reach (study area) were investigated. Four of the study sites were located between river kilometer 575 and 580 in a section of the river where fall Chinook salmon have not spawned since aerial surveys were initiated in the 1940s; four sites were located in the spawning reach (river kilometer [rkm] 590 to 603); and one site was located upstream of the spawning reach (rkm 605).

Download or read book Evaluation of Chum and Sockeye Salmon Spawning Habitat in Sloughs and Side Channels of the Middle Susitna River written by Andrew Hoffman and published by . This book was released on 1984 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spawning Site Selection of Coho Salmon Oncorhynchus Kisutch in Susitna River Tributaries Alaska written by Betsy W. McCracken and published by . This book was released on 2021 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coho Salmon Oncorhynchus kisutch are the most widely distributed Pacific salmon species across Alaska. The lack of knowledge surrounding the habitat requirements of this species results in challenges for conservation and management due to natural and anthropogenic pressures. Tributaries of the Susitna River drainage in Alaska support many small and distinct Coho Salmon populations. Heterogeneity of in-stream spawning habitat is an ecological concept known to promote resiliency of salmonid populations. The goal of this study was to investigate the best habitat predictors of spawning site selection and the scale by which spawning habitat should be evaluated for management insights. Scale is particularly important when measuring, assessing, and predicting potential impacts to species from development activities because habitat research at the stream rather than the reach scale can overestimate the amount of available spawning habitat. I investigated a suite of field-measured stream habitat variables paired with empirical Coho Salmon spawning survey data in five tributaries during 2013 and 2014. Physical data was defined as biotic and abiotic surroundings of an organism or population that have an influence on survival, development, and evolution. Mixed-effects modeling results indicated that Coho Salmon spawning-site selection was positively related to gravel substrate and the presence of groundwater flux, and that spawning Coho Salmon avoided cobble substrate. Physical data were analyzed at both the stream and reach scales, and mixed-effects modeling results further concluded that variation in spawning activity at the reach scale (variance = 1.34, SD = 1.16) accounted for more variability and was more predictive than at the stream scale(variance = 0.04, SD = 0.19). This is important because fish habitat-associations identified at the reach scale were not identified at the stream scale. These results highlight the need for multi-scale habitat data collections and analyses to identify the most meaningful fish-habitat associations.

Download or read book Characteristics and Structure of Early and Late Spawning Runs of Chum Salmon Oncorhynchus Keta Walbaum in Streams of Prince William Sound Alaska written by John H. Helle and published by . This book was released on 1960 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Spawning Pacific Salmon on the Trophic and Population Ecology of Stream resident Sculpins written by Noel Richard Swain and published by . This book was released on 2013 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Across the North Pacific coast, marine and freshwater ecosystems are linked by annual spawning runs of Pacific salmon. Although past research has highlighted the importance of these nutrient subsidies to freshwater food webs, their effects on the trophic and population dynamics of freshwater fish remain poorly understood. In this thesis I examined the relative influences of pink (Oncorhynchus gorbuscha) and chum (O. keta) salmon and habitat on the diets, individual condition, and population densities of freshwater prickly sculpins (Cottus asper), and coastrange sculpins (C. aleuticus). I found that sculpin condition and salmon nutrients in sculpin diets increased with the availability and density of spawning salmon, and were influenced by season, sculpin species, body size, and habitat. I also found that salmon density, pH, and habitat were related to sculpin population densities, but that their effects differed between sculpin species. This is the first study to test such relationships for freshwater fishes across wide, natural gradients in salmon spawning density and habitat.

Download or read book Quantifying the Behavioral Response of Spawning Chum Salmon to Elevated Discharges from Bonneville Dam Columbia River written by and published by . This book was released on 2008 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: In unimpounded rivers, Pacific salmon (Oncorhynchus spp.) typically spawn under relatively stable stream flows, with exceptions occurring during periodic precipitation events. In contrast, hydroelectric development has often resulted in an artificial hydrograph characterized by rapid changes in discharge and tailwater elevation that occur on a daily, or even an hourly basis, due to power generation (Cushman 1985; Moog 1993). Consequently, populations of Pacific salmon that are known to spawn in main-stem habitats below hydroelectric dams face the risks of changing habitat suitability, potential redd dewatering, and uncertain spawning success (Hamilton and Buell 1976; Chapman et al. 1986; Dauble et al. 1999; Garland et al. 2003; Connor and Pflug 2004; McMichael et al. 2005). Although the direct effects of a variable hydrograph, such as redd dewatering are apparent, specific effects on spawning behavior remain largely unexplored. Chum salmon (O. keta) that spawn below Bonneville Dam on the Columbia River are particularly vulnerable to the effects of water level fluctuations. Although chum salmon generally spawn in smaller tributaries (Johnson et al. 1997), many fish spawn in main-stem habitats below Bonneville Dam near Ives Island (Tomaro et al. 2007; Figure 1). The primary spawning area near Ives Island is shallow and sensitive to changes in water level caused by hydroelectric power generation at Bonneville Dam. In the past, fluctuating water levels have dewatered redds and changed the amount of available spawning habitat (Garland et al. 2003). To minimize these effects, fishery managers attempt to maintain a stable tailwater elevation at Bonneville Dam of 3.5 m (above mean sea level) during spawning, which ensures adequate water is provided to the primary chum salmon spawning area below the mouth of Hamilton Creek (Figure 1). Given the uncertainty of winter precipitation and water supply, this strategy has been effective at restricting spawning to a specific riverbed elevation and providing minimum spawning flows that have the greatest chance of being maintained through egg incubation and fry emergence. However, managing the lower Columbia River for a stable tailwater elevation does not provide much operational flexibility at Bonneville Dam, which has little storage capacity. When river discharges increase due to rain events, the traditional approach has been to pass excess water at night to maintain stable tailwater elevations during the daytime. The underlying assumption of this strategy, referred to as reverse load following, is that fish do not spawn at night. However, Tiffan et al. (2005) showed that this assumption is false by documenting nighttime spawning by chum salmon in the Ives Island area. Similarly, McMichael et al. (2005) reported nighttime spawning by Chinook salmon (O. tshawytscha) in the Columbia River, indicating that diel spawning may be a common occurrence in Pacific salmon. During the latter portion of the chum spawning period in December 2003 and 2004, discharges from Bonneville Dam increased from an average of 3,398 m3/s (tailwater elevation (almost equal to) 3.5 m above mean sea level) during the day to over 5,664 m3/s (tailwater elevation (almost equal to) 5.1 m) at night, with peak discharges of 7,080 m3/s (tailwater elevation (almost equal to) 6.1 m). This caused concern among fishery managers regarding the potential effects of these high discharges on this population of spawning chum salmon, which is listed under the Endangered Species Act (National Oceanic and Atmospheric Administration 1999). We hypothesized that increased water velocities associated with elevated tailwaters might alter chum salmon spawning behavior if water velocities at redd locations increased beyond the range of suitability (>0.8 m/s; Salo 1991). In 2005, we investigated the movement and behavioral responses of spawning chum salmon at Ives Island to increased tailwater elevations at Bonneville Dam. We used acoustic telemetry to determine if the higher velocities associated with increased tailwater elevations caused fish to leave their redds. We related the duration fish were away from redds and the distances moved to water velocities estimated from a two-dimensional hydrodynamic model. Finally, we described specific changes in spawning behavior (e.g., nest digging; swimming activity) during elevated-tailwater tests using a dual-frequency identification sonar (DIDSON).

Download or read book Physicochemical Characteristics of the Hyporheic Zone Affect Redd Site Selection of Chum and Fall Chinook Salmon Columbia River written by and published by . This book was released on 2001 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chum salmon (Oncorhynchus keta) may historically have been the most abundant species of Columbia River salmon, contributing as much as 50% of the total biomass of all salmon in the Pacific Ocean prior to the 1940's (Neave 1961). By the 1950's, however, run sizes to the Columbia River dropped dramatically and in 1999 the National Marine Fisheries Service (NMFS) listed Columbia River chum salmon as threatened under the Endangered Species Act (ESA; NMFS 1999). Habitat degradation, water diversions, harvest, and artificial propagation are the major human-induced factors that have contributed to the species decline (NMFS 1998). Columbia River chum salmon spawn exclusively in the lower river below Bonneville Dam, including an area near Ives Island. The Ives Island chum salmon are part of the Columbia River evolutionary significant unit (ESU) for this species, and are included in the ESA listing. In addition to chum salmon, fall chinook salmon (O. tshawytscha) also spawn at Ives Island. Spawning surveys conducted at Ives Island over the last several years show that chum and fall chinook salmon spawned in clusters in different locations (US Fish and Wildlife Service and Washington Department of Fish and Wildlife, unpublished data). The presence of redd clusters suggested that fish were selecting specific habitat features within the study area (Geist and Dauble 1998). Understanding the specific features of these spawning areas is needed to quantify the amount of habitat available to each species so that minimum flows can be set to protect fish and maintain high quality habitat.