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Abstract (from Fisheries Magazine): Ecosystem transformation can be defined as the emergence of a selfâorganizing, selfâsustaining, ecological or social–ecological system that deviates from prior ecosystem structure and function. These transformations are occurring across the globe; consequently, a static view of ecosystem processes is likely no longer sufficient for managing fish, wildlife, and other species. We present a framework that encompasses three strategies for fish and wildlife managers dealing with ecosystems vulnerable to transformation. Specifically, managers can resist change and strive to maintain existing ecosystem composition, structure, and function; accept transformation when it is not feasible...
Categories: Publication;
Types: Citation
Climate change is an important factor affecting fish globally. This site provides a comprehensive database of peer-reviewed literature available on how climate change has impacted and will continue to impact inland fishes worldwide. These studies have been compiled through an extensive, systematic primary literature review to identify English-language, peer-reviewed journal publications with projected and documented examples of climate change impacts on inland fishes globally. From this standardized database of existing literature, we can examine global patterns in climate change impacts on inland fish. Following a decision path based on knowledge of how climate has been documented to affect fish biology in five...
This .zip file contains five products that will allow users to recreate the analyses and spatial data figures used in Sergeant et al. 2023, Hypoxia Vulnerability in the Salmon Watersheds of Southeast Alaska: 1) Hypoxia vulnerability calculations (.csv file) at water temperature monitoring sites, 2) Hypoxia vulnerability calculations (.csv file) for stream reaches near hatchery release sites, 3) Habitat characteristics (.csv file) at water temperature monitoring sites, 4) R code (.R file) for recreating Figure 3, modeled contours of the estimated number of pink salmon/m2 to create hypoxia in Southeast Alaska streams across all potential combinations of velocity, depth, and water temperature, 5) Esri map package (.mpk...
Pulsed subsidy events create ephemeral fluxes of hyper-abundant resources that can shape annual patterns of consumption and growth for recipient consumers. However, environmental conditions strongly affect local resource availability for much of the year, and can heavily impact consumer foraging and growth patterns prior to pulsed subsidy events. Thus, a consumer’s capacity to exploit pulse subsidy resources may be influenced by antecedent environmental conditions, but this has rarely been shown in nature and is unknown in aquatic ecosystems. We sampled fish at a high frequency (daily - weekly measurements) to examine the importance of hydrologic variation and a salmon pulse subsidy on the foraging patterns of two...
Categories: Data;
Tags: Coho Salmon,
Dolly Varden,
Fish foraging,
Southeast Alaska,
USGS Science Data Catalog (SDC),
Abstract (from Society for Conservation Biology): Climate change will continue to be an important consideration for conservation practitioners. However, uncertainty in identifying appropriate management strategies, particularly for understudied species and regions, constrains the implementation of science-based solutions and adaptation strategies. Here, we share a decision-path approach to reduce uncertainty in climate change responses of inland fishes to inform conservation and adaptation planning. With the Fish and Climate Change database (FiCli), a comprehensive, online, public database of peer-reviewed literature on documented and projected climate impacts to inland fishes, users can identify relevant studies...
Categories: Publication;
Types: Citation
Viable sockeye salmon populations are critical to the economy, culture, and freshwater ecosystems of Bristol Bay in Western Alaska, and it is unclear how populations might respond to warming temperatures during the critical life history stages of spawning and embryo incubation. The overarching goal of the project is to understand how temperature might influence population-specific patterns of embryo incubation, timing of hatching and fry emergence, and sockeye salmon embryo survival. By combining analyses of data from two large lake systems in the Kvichak watershed, laboratory rearing experiments to elucidate functional relationships, and simulation modeling, this project quantifies biological responses to changing...
Data from high frequency sampling of multiple carbon forms were collected in a predominately rain-fed watershed in Southeast Alaska during the main run-off season (May-October 2021). The dataset includes dissolved organic carbon, particulate organic carbon, coarse particulate organic carbon, and invertebrate biomass carbon point samples and daily stream flow. The objective of this study was to collect data on carbon export and flow to model watershed export of carbon forms.
Categories: Data;
Tags: Aquatic Biology,
Southeast Alaska,
USGS Science Data Catalog (SDC),
Water Resources,
biogeochemistry,
In the Gulf of Alaska, streams will experience more dramatic low water events, interspersed with larger and potentially more frequent high flow events in the coming decades. Reduced stream flows are likely to occur due to diminished snowpack and seasonal droughts, while higher flow events are likely to occur with more frequent storms and rain-on-snow events. These changes are likely to influence the growth trajectories of juvenile salmon, such as coho salmon and chinook salmon, that live up to two years in freshwater before migrating to the ocean. Stream flows can influence juvenile salmon growth by modifying food availability, water clarity, temperature, and predation risk. This high-resolution study examines...
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2020,
Alaska,
Alaska CASC,
CASC,
Fish,
Abstract (from American Fisheries Society): Climate change is a global persistent threat to fish and fish habitats throughout North America. Climate-induced modification of environmental regimes, including changes in streamflow, water temperature, salinity, storm surges, and habitat connectivity can change fish physiology, disrupt spawning cues, cause fish extinctions and invasions, and alter fish community structure. Reducing greenhouse emissions remains the primary mechanism to slow the pace of climate change, but local and regional management agencies and stakeholders have developed an arsenal of adaptation strategies to help partially mitigate the effects of climate change on fish. We summarize common stressors...
Categories: Publication;
Types: Citation
Abstract (from Scientific Data): Inland fishes provide important ecosystem services to communities worldwide and are especially vulnerable to the impacts of climate change. Fish respond to climate change in diverse and nuanced ways, which creates challenges for practitioners of fish conservation, climate change adaptation, and management. Although climate change is known to affect fish globally, a comprehensive online, public database of how climate change has impacted inland fishes worldwide and adaptation or management practices that may address these impacts does not exist. We conducted an extensive, systematic primary literature review to identify peer-reviewed journal publications describing projected and documented...
Categories: Publication;
Types: Citation;
Tags: Fish,
National CASC,
Rivers, Streams and Lakes,
Science Tools for Managers,
State of the Science,
This project will assess impacts of climate change on stream resources by considering the role of thermal heterogeneity and altered hydrologic regimes. The project will look at streams in Washington, Oregon, and California to develop a case study that stream stewards and conservation planners can use to assess vulnerability for Pacific salmon.Successful adaptation strategies for freshwater biota will consider how spatial patterns in water temperature may respond to climate change. Using remotely sensed spatially continuous maximum water temperature data for~ 30 large rivers throughout the lower portion of the NPLCC, we will map locations of cold water patches, identify potential hydroclimatic and landscape drivers,...
Categories: Data,
Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2014,
Academics & scientific researchers,
Anadromous fish,
Applications and Tools,
California,
This report is structured around the specific objectives in the format of three stand-alone manuscripts that are in the process of submission to peer-reviewed journals. The first manuscript includes objectives 1-2, the second manuscript addresses objective 3, and the final manuscript objective 4. The overarching goal of the proposal was to understand how both recently experienced and projected water temperatures might influence population-specific patterns of embryo incubation, timing of hatching and fry emergence, and survival of sockeye salmon embryos. Additionally, we sought to explore the potential for adaptation in a heritable threshold life history trait that shapes whether an individual migrates to the ocean...
Assessments that incorporate areas from land-to-ocean, or “ridge-to-reef", are critical to examine how land-use practices are altering stream discharge and nearshore marine health and productivity. Stream systems in both Alaska and HawaiĘťi are expected to experience changes in water quality associated with changing environmental conditions and increased human-use. Watershed systems throughout the Hawaiian Islands are currently experiencing impacts from climate change that affect groundwater recharge and surface runoff, erosion, and total streamflow, and cause degradation of nearshore marine habitats. This study can provide useful insight for both Alaska and HawaiĘťi by providing resources on how patterns in stream...
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2021,
Alaska,
CASC,
Coral Reefs,
Coral Reefs,
Streamflow controls many freshwater and marine processes, including salinity profiles, sediment composition, fluxes of nutrients, and the timing of animal migrations. Watersheds that border the Gulf of Alaska (GOA) comprise over 400,000 km2 of largely pristine freshwater habitats and provide ecosystem services such as reliable fisheries for local and global food production. Yet no comprehensive watershedâscale description of current temporal and spatial patterns of streamflow exists within the coastal GOA. This is an immediate need because the spatial distribution of future streamflow patterns may shift dramatically due to warming air temperature, increased rainfall, diminishing snowpack, and rapid glacial recession....
Categories: Publication;
Types: Citation
Alaska is an ecologically, commercially, and recreationally diverse state, providing value to people and terrestrial and aquatic species alike. Presently, Alaska is experiencing climatic change faster than any other area of the United States, but across the state, comprehensive environmental monitoring is logistically difficult and expensive. For instance, only about 1% of U.S Geological Survey (USGS) stream gages are in Alaska, and only about 50% of those gages measure water temperature, an important climate change indicator. In this study, predictive models are being used to map stream temperatures under current and future climate scenarios across the Yukon and Kuskokwim River basins (YKRB) at the stream reach...
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2020,
Alaska,
Alaska CASC,
CASC,
Drought, Fire and Extreme Weather,
Chinook Salmon (Oncorhynchus tshawytscha) are an important commercial, subsistence, and recreational fishery resource in Alaska, and recent population declines have resulted in closures of some Chinook Salmon fisheries. Research into environmental factors involved in the decline of salmon stocks has exposed information gaps regarding fine-scale freshwater habitat quality known to influence Chinook Salmon productivity. We developed spatially-explicit intrinsic habitat potential models for Chinook Salmon freshwater spawning and rearing life-stages based on geomorphic stream network attributes (e.g., gradient, mean annual flow, valley bottom width). Model predictions were applied to individual stream reaches and summarized...
Nearshore marine ecosystems in Alaska and Hawai‘i rely heavily on organic materials and nutrients delivered by rivers and streams. It is hypothesized that the magnitude and timing of stream flows influences this delivery of materials to coastal ecosystems. However, despite previous research on the topic, there is still considerable uncertainty about how stream flow may influence these land-to-water (“ridge-to-reef") linkages, and how climate change induced shifts in runoff may ripple across ecosystem boundaries to influence estuary and nearshore marine ecosystems and species of cultural and commercial importance (e.g., Pacific salmon, gobies, and coral reefs). This project is a collaborative study to examine...
Categories: Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2020,
Alaska,
Alaska CASC,
CASC,
Fish,
An important unresolved question is how populations of coldwater-dependent fishes will respond to rapidly warming water temperatures. For example, the culturally and economically important group, Pacific salmon (Oncorhynchus spp.), experience site-specific thermal regimes during early development that could be disrupted by warming. To test for thermal local adaptation and heritable phenotypic plasticity in Pacific salmon embryos, we measured the developmental rate, survival, and body size at hatching in two populations of sockeye salmon (Oncorhynchus nerka) that overlap in timing of spawning but incubate in contrasting natural thermal regimes. Using a split half-sibling design, we exposed embryos of 10 families...
This project will assess impacts of climate change on stream resources by considering the role of thermal heterogeneity and altered hydrologic regimes. The project will look at streams in Washington, Oregon, and California to develop a case study that stream stewards and conservation planners can use to assess vulnerability for Pacific salmon. Successful adaptation strategies for freshwater biota will consider how spatial patterns in water temperature may respond to climate change. Using remotely sensed spatially continuous maximum water temperature data for~ 30 large rivers throughout the lower portion of the NPLCC, we will map locations of cold water patches, identify potential hydroclimatic and landscape drivers,...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Academics & scientific researchers,
Anadromous fish,
California,
Climate Change,
Conservation Planning,
The overarching goal of this project is to develop spawning and rearing habitat potential estimates for the Yukon and Kuskokwim river basins in Alaska. To accomplish this goal we will compile georeferenced data on Chinook salmon juvenile and adult habitat use from existing databases, and incorporate input from agencies and community members solicited through targeted workshops to develop habitat potential models and a user-friendly tool to facilitate habitat potential mapping. Our specific objectives are to: 1) Compile georeferenced juvenile and adult Chinook salmon distribution data and classify these data based on uncertainty 2) Use previously-developed Chinook salmon models from Alaska to produce initial maps...
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