Jameal F. Samhouri

• Northwest Fisheries Science Center

As global climate change and anthropogenic activities amplify widespread environmental variability, there is a strong need for management strategies that incorporate relationships between ecosystem components. This need is especially apparent when changes in environmental drivers cause threshold responses (abrupt, nonlinear changes) in ecosystems....

The West Coast of the U.S. has a vast offshore wind energy (OWE) electricity generation potential with value on the order of billions of USD, and pressure is mounting to develop large OWE projects. However, this seascape has numerous existing resource extraction uses, including a multi-billion dollar commercial fishing industry, which create the po...

Climate variability and change are having dramatic effects on marine species, fisheries, and fishing communities. Climate perturbations elicit fishery management responses intended to mitigate negative effects, but the responses often do not account for the complexity of fisheries systems, leading to unintended consequences. However, including more...

Climate change can impact marine ecosystems through many biological and ecological processes. Ecosystem models are one tool that can be used to simulate how the complex impacts of climate change may manifest in a warming world. In this study, we used an end‐to‐end Atlantis ecosystem model to compare and contrast the effects of climate‐driven specie...

Understanding the dynamic relationship between marine species and their changing environments is critical for ecosystem based management, particularly as coastal ecosystems experience rapid change (e.g., general warming, marine heat waves). In this paper, we present a novel statistical approach to robustly estimate and track the thermal niches of 3...

As climate change reshapes marine ecosystems, the dynamics of fish stocks are undergoing rapid transformation. Understanding these shifts and their multifaceted impacts demands more than just scientific inquiry; it necessitates a fusion of knowledge, collaboration, and action. However, the translation of cutting-edge research on the changing distri...

Understanding the dynamic relationship between marine species and their changing environments is critical for ecosystem based management, particularly as coastal ecosystems experience rapid change (e.g., general warming, marine heat waves). In this paper, we present a novel statistical approach to robustly estimate and track the thermal niches of 3...

Commercial fisheries along the US West Coast are important components of local and regional economies. They use various fishing gear, target a high diversity of species, and are highly spatially heterogeneous, making it challenging to generate a synoptic picture of fisheries activity in the region. Still, understanding the spatial and temporal dyna...

Climate change is expected to alter harmful algal bloom (HAB) dynamics in marine and freshwater systems around the world, with some regions already experiencing significant increases in HAB events. There has been considerable investment of effort to identify, characterize, track, and predict the direction and magnitude of HAB response to climate va...

NOAA provides the Pacific Fishery Management Council (Council) with a yearly update on the status of the California Current Ecosystem (CCE), as derived from environmental, biological, economic and social indicators. NOAA’s California Current Integrated Ecosystem Assessment (CCIEA) team is responsible for this edited report, with contributions by ov...

From fishers to farmers, people across the planet who rely directly upon natural resources for their livelihoods and well-being face extensive impacts from climate change. However, local- and regional-scale impacts and associated risks can vary geographically, and the implications for development of adaptation pathways that will be most effective f...

Climate change drives species distribution shifts, affecting the availability of resources people rely upon for food and livelihoods. These impacts are complex, manifest at local scales, and have diverse effects across multiple species. However, for wild capture fisheries, current understanding is dominated by predictions for individual species at...

From fishers to farmers, people across the planet who rely directly upon natural resources for their livelihoods and well-being face extensive impacts from climate change. However, local- and regional-scale impacts and associated risks can vary geographically, and the implications for development of adaptation pathways that will be most effective f...

Despite progress in understanding and predicting climate change impacts and possible responses for US marine fisheries, use of climate-related information in federal fishery management decisions remains limited. One barrier to progress in linking climate knowledge to management action is that individual management bodies' efforts tend to be isolate...

As animal populations approach environmental carrying capacity, competition for food increases, generally leading to decreased individual energy intake rate. Energy-intake rate can therefore be used as one metric of population status relative to carrying capacity. Focal observations of Sea Otter (Enhydra lutris) foraging behavior have been used thr...

Introduction Understanding how abundance, productivity and distribution of individual species may respond to climate change is a critical first step towards anticipating alterations in marine ecosystem structure and function, as well as developing strategies to adapt to the full range of potential changes. Methods This study applies the NOAA (Nati...

Climate change drives species distribution shifts, impacting the availability of resources people rely upon for food and livelihoods. These impacts are complex, manifest at local scales and have diverse effects across multiple species. Yet, for wild capture fisheries current understanding is dominated by predictions for individual species at coarse...

Many marine species are shifting their distributions in response to changing ocean conditions, posing significant challenges and risks for fisheries management. Species distribution models (SDMs) are used to project future species distributions in the face of a changing climate. Information to fit SDMs generally comes from two main sources: fishery...

A huge proportion of the world’s population resides in urban areas along the coast. As cities expand, the ability of coastal ecosystems to provide the benefits people derive from nature, ranging from food from fisheries to coastal defense to maritime transportation and beyond, is in question. While it is well understood that coastal development cha...

Climate change is already impacting coastal communities, and ongoing and future shifts in fisheries species productivity from climate change have implications for the livelihoods and cultures of coastal communities. Harvested marine species in the California Current Large Marine Ecosystem support U.S. West Coast communities economically, socially,...

The timing, or phenology, of predator activity in relation to their prey is critical for survival and fitness, yet rarely quantified for marine species, even those of conservation concern. We use a large database of professional and crowd-sourced observations analyzed with hierarchical spline occupancy models to quantify seasonal variation in occur...

A major challenge in sustainability science is identifying targets that maximize ecosystem benefits to humanity while minimizing the risk of crossing critical system thresholds. One critical threshold is the biomass at which populations become so depleted that their population growth rates become negative—depensation. Here, we evaluate how the valu...

Forage fish are schooling species commonly occurring in both offshore pelagic and nearshore coastal habitats. Beyond use by some species for spawning, the dynamics of nearshore habitat use are not well understood. The objective of our study was to evaluate the spring–summer dynamics of forage fish occurrence in nearshore habitats of the Strait of J...

Restoration of degraded coastal and estuarine habitats owing to human activities is a major global concern. In Puget Sound, Washington, USA, removal of hard armor from beaches and intertidal zones has become a priority for state and local agencies. However, the effectiveness of these shoreline restoration programs for subtidal habitats and fish is...

The unusual blue color polymorphism of lingcod (Ophiodon elongatus) is the subject of much speculation but little empirical research; ~20% of lingcod individuals exhibit this striking blue color morph, which is discrete from and found within the same populations as the more common brown morph. In other species, color polymorphisms are intimately li...

Despite the increasing frequency and magnitude of extreme climate events, little is known about how their impacts flow through social and ecological systems or whether management actions can dampen deleterious effects. We examined how the record 2014–2016 Northeast Pacific marine heatwave influenced trade-offs in managing conflict between conservat...

Environmental forces can create spatially synchronous dynamics among nearby populations. However, increased climate variability, driven by anthropogenic climate change, will likely enhance synchrony among spatially disparate populations. Population synchrony may lead to greater fluctuations in abundance, but the consequences of population synchrony...

The impacts of invasive lionfish ( Pterois volitans/miles ) on native coral reef populations in the Western Atlantic Ocean and Caribbean Sea can be enormous. However, how much lionfish differ from native predators and whether their effects outweigh the abundant mesopredators that occupy many reefs invite continued examination. Here, we present empi...

Small-scale fisheries (SSFs) around the world are increasingly facing pressures from a range of environmental, economic, and social sources. To sustain SSFs, it is imperative to understand how fishing communities adapt to these pressures. In particular, to manage economic risks fishers often catch many different species; diversifying harvest portfo...

Intraspecific variation in external and internal pigmentation is common among fishes and explained by a variety of biological and ecological factors. Blue-colored flesh in fishes is relatively rare but has been documented in some species of the sculpin, greenling, and perch families. Diet, starvation, photoprotection, and camouflage have all been s...

Dynamic ocean management (DOM), a type of marine spatial planning in which management decisions are updated in response to changing environmental, biological, or socioeconomic conditions, holds promise for balancing tradeoffs between conservation and marine resource use. However, as climate change continues to drive unprecedented oceanic changes, i...

On the U.S. West Coast, reports of whales entangled in fishing gear increased dramatically in 2014. In this study, a time series of fishing activity maps was developed from 2009 to 2016 for the four fixed‐gear fisheries most commonly implicated in entanglements. Maps were generated using vessel monitoring system (VMS) data linked to port‐level land...

The vast spatial extent of the ocean presents a major challenge for monitoring changes in marine biodiversity and connecting those changes to management practices. Remote-sensing offers promise for overcoming this problem in a cost-effective, tractable way, but requires interdisciplinary expertise to identify robust approaches. In this study, we us...

Science-based natural resource management is necessary for agencies to effectively meet their goals and mandates. However, this scientific basis needs to be advanced and evolved with ecosystems experiencing unprecedented events that challenge conventional management frameworks. Effectively managing marine resources and achieving agency missions req...

Significance Climate shocks are increasingly disruptive to global food systems, with far-reaching consequences for resource-based communities. Yet quantitative assessments of community impacts rarely account for economic connectivity between alternative resources. We show that patterns of resource use influence the sensitivity of US West Coast fish...

Ecology is often governed by nonlinear dynamics. Nonlinear ecological relationships can include thresholds-incremental changes in drivers that provoke disproportionately large ecological responses. Among the species that experience nonlinear and threshold dynamics are Pacific salmon (Oncor-hynchus spp.). These culturally, ecologically, and economic...

Many organisms exhibit tremendous fluctuations in population abundance and experience unexpected collapse. Conservationists seeking to minimize region-wide variability in resources and reduce extinction risk often seek to preserve a metapopulation portfolio of spatially asynchronous subpopulations connected by dispersal. However, portfolio properti...

Climate impacts disproportionately affect people that are most vulnerable and least able to adapt. The extent to which these equity impacts extend to fishing communities in the developed world is a question that has received surprisingly little attention. Here we explore the distributional impacts of a climate shock in one of the largest and most v...

Understanding the impact of plastic debris on marine birds is important for conservation of some species, and assessing risk from this anthropogenic threat requires high-quality distribution data for both marine birds and plastic debris. We applied a risk assessment framework to explore the relative risk for 19 marine bird species posed by plastic...

Long-term mechanistic research and monitoring provides integral science support for ecosystem-based management (EBM) of resources, activities and services. Decades of oceanographic and ecological research by Bill Peterson and colleagues along the Newport Hydrographic Line (NH Line) provides essential context for understanding and managing Pacific s...

Preseason abundance forecasts drive management of U.S. West Coast salmon fisheries, yet little is known about how environmental variability influences forecast performance. We compared forecasts of Chinook salmon (Oncorhynchus tshawytscha) against returns for I) key California-Oregon ocean fishery stocks and II) high priority prey stocks for endang...

Recent warnings from scientists suggest there is limited time to enact policies to avert wide‐ranging ecological and social damage from climate change. In the United States, discussions about comprehensive national policies to avert climate change have begun, with “Green New Deal” proposals and climate plans put forth by members of Congress and pre...

The Anthropocene has brought substantial change to ocean ecosystems, but whether this age will bring more or less marine disease is unknown. In recent years, the accelerating tempo of epizootic and zoonotic disease events has made it seem as if disease is on the rise. Is this apparent increase in disease due to increased observation and sampling ef...

Unanticipated declines among exploited species have commonly occurred despite harvests that appeared sustainable prior to collapse. This is particularly true in the oceans where spatial scales of management are often mismatched with spatially complex metapopulations. We explore causes, consequences, and potential solutions for spatial mismatches in...

Fishing communities are increasingly required to adapt to environmentally driven changes in the availability of fish stocks. Here, we examined trends in the distribution and biomass of five commercial target species (dover sole, thornyheads, sablefish, lingcod, and petrale sole) on the US west coast to determine how their availability to fishing po...

Species distribution models (SDMs) are a common approach to describing species’ space‐use and spatially‐explicit abundance. With a myriad of model types, methods and parameterization options available, it is challenging to make informed decisions about how to build robust SDMs appropriate for a given purpose. One key component of SDM development is...

With the anticipated boom in the ‘blue economy’ and associated increases in industrialization across the world’s oceans, new and complex risks are being introduced to ocean ecosystems. As a result, conservation and resource management increasingly look to factor in potential interactions among the social, ecological and economic components of these...

Background Studies that attempt to measure shifts in species distributions often consider a single species in isolation. However, understanding changes in spatial overlap between predators and their prey might provide deeper insight into how species redistribution affects food web dynamics. Predator–prey overlap metrics Here, we review a suite of...

The ecology of an epibiont may depend not only on the dynamics of its biogenic habitat but also on microclimate variation generated within aggregations of its host, a process called physical ecosystem engineering. This study explored variation in the abundance and demography of Membranipora, a suspension-feeding bryozoan, within forests of giant ke...

Preseason abundance forecasts drive management of salmon fisheries off the U.S. West Coast, yet little is known about how environmental variability influences forecast performance. Understanding shared patterns in forecast performance can identify scenarios with heightened management risk due to shared over/under-forecasting of a large proportion o...

It is increasingly evident that climate change is having significant impacts on marine ecosystems and dependent fisheries. Yet, translating climate science into management actions and policies is an ongoing challenge. In particular, four aspects have confounded implementation of climate-resilient management: (i) regional management tools may not be...

The intensive harvest of wild populations for food can pose a risk to food security and to conservation goals. While ecosystem approaches to management offer a potential means to balance those risks, they require a method of assessment that is commensurate across multiple objectives. A major challenge is conducting these assessments in a way that c...

Ocean recoveries are moving targets As the human population has grown, our demands on the ocean have increased rapidly. These demands have similarly increased the pressure we place on these systems, and we now cause considerable damage globally. If we want to maintain healthy ocean ecosystems into the future, we must learn to use ocean resources in...

The recovery of predators has the potential to restore ecosystems and fundamentally alter the services they provide. One iconic example of this is keystone predation by sea otters in the Northeast Pacific. Here, we combine spatial time series of sea otter abundance, canopy kelp area, and benthic invertebrate abundance from Washington State, USA, to...

Unanticipated declines among exploited species frequently occur despite harvests that appear sustainable. This is common in the oceans, where spatial scales of management can be mismatched with spatially dynamic metapopulations. We explore causes, consequences and potential solutions for spatial mismatches in metapopulations of an important forage...

The seascapes on which many millions of people make their living and secure food have complex and dynamic spatial features-the figurative hills and valleys-that influence where and how people work at sea. Here, we quantify the physical mosaic of the surface ocean by identifying Lagrangian Coherent Structures for a whole seascape-the U.S. California...

Conservation efforts tend to focus on the direct impacts humans have on their surrounding environment; however there are also many ways in which people indirectly affect ecosystems. Recent research on ecological subsidies—the transfer of energy and nutrients from one ecosystem to another—has highlighted the importance of nutrient exchange for maint...

Ecosystem-based management (EBM) in marine ecosystems considers impacts caused by complex interactions between environmental and anthropogenic pressures (i.e., oceanographic, climatic, socio-economic) and marine communities. EBM depends, in part, on ecological indicators that facilitate understanding of inherent properties and the dynamics of press...

Marine social–ecological systems are constantly changing, and fishers who make a living from working the seas are continually adapting in response to different sources of variability. One main way in which fishers can adapt to ecosystem change is to change the fisheries they participate in. This acts to connect fisheries, creating interlinked netwo...

A longstanding goal in coral reef ecology is to estimate the baseline states of ecological communities and the extent to which human activities have perturbed them. Often, baseline estimates rely upon observations from remote, uninhabited areas, highlighting dramatic differences in fish communities compared to populated areas. However, previous stu...

The oceans are changing more rapidly than ever before. Unprecedented climatic variability is interacting with unmistakable long-term trends, all against a backdrop of intensifying human activities. What remains unclear, however, is how to evaluate whether conditions have changed sufficiently to pro- voke major responses of species, habitats, and co...

One of the twenty-first century's greatest environmental challenges is to recover and restore species, habitats and ecosystems. The decision about how to initiate restoration is best-informed by an understanding of the linkages between ecosystem components and, given these linkages, an appreciation of the consequences of choosing to recover one eco...

Supplemental Material, including figures

In the face of increasing threats to biodiversity, the advancement of methods for surveying biological communities is a major priority for ecologists. Recent advances in molecular biological technologies have made it possible to detect and sequence DNA from environmental samples (environmental DNA or eDNA); however, eDNA techniques have not yet see...

The ubiquity of trophic downgrading has led to interest in the consequences of mesopredator release on prey communities and ecosystems. This issue is of particular concern for reef-fish communities, where predation is a key process driving ecological and evolutionary dynamics. Here, we synthesize existing experiments that have isolated the effects...

Given the rapid rise of environmental DNA (eDNA) surveys in ecology and environmental science, it is important to be able to compare the results of these surveys to traditional methods of measuring biodiversity. Here we compare samples from a traditional method (a manual tow-net) to companion eDNA samples sequenced at three different genetic loci....

Risk assessments quantify the probability of undesirable events along with their consequences. They are used to prioritize management interventions and assess tradeoffs, serving as an essential component of ecosystem-based management (EBM). A central objective of most risk assessments for conservation and management is to characterize uncertainty a...

In the face of increasing threats to biodiversity, the advancement of methods for surveying biological communities is a major priority for ecologists. Recent advances in molecular biological technologies have made it possible to detect and sequence DNA from environmental samples (environmental DNA or eDNA); however, eDNA techniques have not yet see...

In the face of increasing threats to biodiversity, the advancement of methods for surveying biological communities is a major priority for ecologists. Recent advances in molecular biological technologies have made it possible to detect and sequence DNA from environmental samples (environmental DNA or eDNA); however, eDNA techniques have not yet see...

Despite decades of work in environmental science and ecology, estimating human influences on ecosystems remains challenging. This is partly due to complex chains of causation among ecosystem elements, exacerbated by the difficulty of collecting biological data at sufficient spatial, temporal, and taxonomic scales. Here, we demonstrate the utility o...

Dataset used for analysis

Analytical code used for analysis

Supplementary analyses and figures