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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 changes ecosystems, quantitative insights about how terrestrial urbanization fundamentally alters ecosystem structure and function in adjacent freshwater and downstream coastal marine habitats remain rare, though a general expectation is that impacts of terrestrial urbanization will attenuate from land to freshwater to coastal marine habitats. Empirical assessments of these phenomena are especially important for species that rely on freshwater and coastal marine habitats at multiple points in their life cycles, including endangered and threatened Pacific salmon (Oncorhynchus spp.). We investigated associations between landscape-scale urbanization and ecosystem structure (biodiversity of epibenthic invertebrate taxa) and function (benthic net primary productivity and decomposition) in freshwater and coastal marine habitats across six pairs of more and less urbanized, coastal watersheds in Puget Sound, WA, USA, using principal components analysis, analysis of covariance, and Mantel tests. Greater upland urbanization was associated with greater reductions in freshwater biodiversity, measured as the density and evenness of epibenthic invertebrate families. In contrast and surprisingly, however, coastal marine biodiversity (measured as the density and evenness of epibenthic invertebrate families) tended to be higher at more urbanized sites, suggesting the potential role of low to moderate levels of urbanization-related disturbance in determining coastal marine biodiversity patterns. We found no statistical association between urbanization and freshwater and coastal marine ecosystem functions, estimated from changes in accumulated algal biomass on tiles (benthic net primary productivity) and loss of biomass from litter bags (decomposition). In addition, there was no evidence that changes in ecosystem structure and function with urbanization were more severe in freshwater than coastal marine habitats, as might be expected if the land-sea boundary diminished effects of landscape-scale urbanization. Our results suggest that the effects of urbanization can be complex and that attention to terrestrial, freshwater, and coastal marine systems in concert will produce more effective, ecosystem-based management.

Despite the significant advances in making monthly or seasonal forecasts of weather, ocean hypoxia, harmful algal blooms and marine pathogens, few such forecasting efforts have extended to the ecology of upper trophic level marine species. Here, we test our ability to use short-term (up to 9 months) predictions of ocean conditions to create a novel forecast of the spatial distribution of Pacific sardine, Sardinops sagax. Predictions of ocean conditions are derived using the output from the Climate Forecast System (CFS) model downscaled through the Regional Ocean Modeling System (ROMS). Using generalized additive models (GAMs), we estimated significant relationships between sardine presence in a test year (2009) and salinity and temperature. The model, fitted to 2009 data, had a moderate skill [area under the curve (AUC) = 0.67] in predicting 2009 sardine distributions, 5–8 months in advance. Preliminary tests indicate that the model also had the skill to predict sardine presence in August 2013 (AUC = 0.85) and August 2014 (AUC = 0.96), 4–5 months in advance. The approach could be used to provide fishery managers with an early warning of distributional shifts of this species, which migrates from the U.S.–Mexico border to as far north as British Columbia, Canada, in summers with warm water and other favorable ocean conditions. We expect seasonal and monthly forecasts of ocean conditions to be broadly useful for predicting spatial distributions of other pelagic and midwater species.

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 salmon Oncorhynchus spp. and other marine resources in the California Current ecosystem. This research program helped federal scientists convey the significance of the northeast Pacific marine heatwave (2013–2016) to fisheries managers and stakeholders. Particularly illustrative were shifts in the composition of the copepod community, which reflected feeding conditions for Pacific salmon and other consumers. We identify six traits of the dataset produced by Peterson and colleagues that have made it especially valuable for informing management: (i) it has generated robust ecosystem indicators; (ii) it is long-term; (iii) it is associated with meaningful ecological mechanisms; (iv) it relates to ecosystem components of high societal value; (v) it can represent processes and lags at meaningful temporal scales; and (vi) it is part of a broader, integrative science effort. This research effort underscores the importance of developing and sustaining long-term mechanistic research and monitoring along the U.S. West Coast and elsewhere in the world.

Nearshore habitats play a vital role in the life cycles of many marine fishes. These habitats are particularly important for Pacific herring Clupea pallasii, which rely on submerged vegetation in the shallow subtidal for spawning habitat and egg incubation. However, little is known about spatial or temporal variation in egg success or how spawning habitat may affect herring early life history. We estimated herring egg loss rates across multiple spawning vegetations in 5 subpopulations of Pacific herring in Puget Sound (USA), an urbanized estuarine system. We found enormous variation in herring egg loss among subpopulations (range of daily loss rates: 5 to 70%) and in egg loss of eggs reared under common garden conditions (range of cumulative loss: 20 to 100%). Egg loss varied by subpopulation but not by spawning vegetation type. Exploratory analyses suggest both wave height and land use patterns may affect hatch success. Using historical survey data, we found that a large proportion of spawning habitat available to Puget Sound herring remains unused each year. Furthermore, we found limited evidence that eggs were deposited dis- proportionally on particular vegetation types; only the non-indigenous brown algae Sargassum mu- ticum was spawned on more than expected by chance. Our results demonstrate that Puget Sound herring are not limited by the amount of available suitable spawning vegetation, and that native vegetation is not preferred over other vegetation types for herring spawning. Rather, it appears that other terrestrial or marine variables are likely determinants of herring egg loss.

Systematic scenario analysis is increasingly being used as an approach to evaluate ecosystem-based management options, often using “storylines” communicated through computer-generated (CG) images or visualizations. To explore potential issues associated with using CG imagery for conveying scenarios of habitat restoration we performed experiments in the Puget Sound, Washington region in which we asked whether respondents could differentiate among images of varying seagrass density and spatial extent, and if the presence of humans in the images affected these assessments and their perceptions of ecosystem health. Respondents were able to grossly determine relative seagrass density in the images, but only about 50% of them were able to determine this perfectly. Most errors occurred when the difference in density was small: approximately 20 shoot m −2 . The ability to correctly distinguish among images was inversely correlated with educational level. The presence or absence of people in the imagery did not influence the ability of respondents to correctly sort images, nor did it affect perceptions of ecosystem “health”. Taken together, the results suggest that such imagery can be useful as basis for communicating large differences in ecological conditions, but may be less informative as means to convey marginal changes in ecological structure. This work begins to highlight some of the pitfalls, but also the promise, of the use of CG visualization in marine resource management.

We developed a food web model of central Puget Sound to provide science-based support for ecosystem-based management and to refine our understanding of bottom-up and top-down trophic forcing. Phytoplankton accounted for a large fraction of total biomass, total throughput, and caused considerable bottom-up effects in most functional groups in a dynamic simulation fit to time series data from 1981 to 2000. Top-down control was most apparent in the case of bald eagles (Haliaeetus leucocephalus), which exhibited keystone tendencies and appeared capable of causing trophic cascades. Increasing top-down control in several predator–prey relationships improved model fits to time series data from 1981 to 2000, but not as much as introducing non-equilibrium dynamics (biomass accumulation terms) to several key vertebrates. Fishing had little effect on system dynamics. Our model appears well-suited for addressing strategic, scenario-based questions of how the community as a whole will respond to management actions.

The broadnose sevengill shark (Notorynchus cepedianus) is a high-order marine predator distributed worldwide in shallow coastal waters of temperate seas. Recent reports have suggested it may be a prevalent component of Pacific Northwest coastal estuarine communities, although biological characteristics of the shark population remain undocumented despite growing interest in recreational harvest of the species. Longline sampling was conducted in Willapa Bay and Grays Harbor, Washington, USA seasonally during 2003–2006 to collect sevengill shark size, maturity, and sex ratio data, and establish some baseline catch rate information. Sevengill sharks were collected on 65% of longline sets and catches were composed of subadult and mature individuals (122–283 cm TL) of both sexes. Most male sevengill sharks were large sexually mature adults, based on external clasper calcification levels, whereas most comparably sized females were considered subadults, based on literature-based size-at–maturity estimates. Neonates and young sharks

In Puget Sound, WA (USA), rockfish (Sebastes spp.) have significantly declined in abundance, with multiple petitions to list individual species under the Endangered Species Act. In order to better understand the ecological legacy of rockfish fishing to the Puget Sound ecosystem, the local history of rockfish exploitation was reviewed, focusing on the socioeconomic forces and management decisions which influenced the trajectory of landings. Rockfish have always been harvested for human consumption in the region, but over time exploitation patterns have changed from an opportunistic subsistence activity by indigenous peoples, to a year-round target of commercial and recreational interests. Annual commercial and recreational harvests together peaked (almost 400 mt) in the early 1980s as anglers’ attitudes changed, gear technology improved, rockfish became more familiar to the market, human population increased, and agency programs promoted fisheries to sustain employment. Rockfishes were generally not managed intensely or with conservation goals in mind until the late 1980s, in part due to scientific shortcomings and a lack of resources. By the time management actions were deemed necessary, the greatest harvest had already occurred. However, the low intrinsic productivity of most rockfish species suggests that the legacy of fishing will remain for years to come. As managers strive to restore the integrity and resilience of Puget Sound, they must realize the significance of historical fishery removals to the ecosystem and use the proper social and economic incentives to drive individual behavior toward these ecosystem goals.

The bluntnose sixgill shark Hexanchus griseus is a wide-ranging marine predator and the largest predatory shark in Puget Sound. Biological characteristics of the Puget Sound bluntnose sixgill shark population remain largely undocumented, despite a recent escalation in recreational angling for the species. Standardized longline sampling, supplemented with other opportunistic collections, was used to collect size, sex ratio, and relative catch rate data at three locations during 2006–2008. Fishing trials were also used to examine the effect of soak time, fishing depth, and time of day on catch rates. Captured bluntnose sixgill sharks were exclusively subadults (175–315 cm total length) found in approximately equal sex ratios in all seasons. Catch rates were highest in Elliott Bay, the urbanized port of Seattle, Washington, and were not affected by sampling season. Catch information derived from hook timers implies that the sharks locate and encounter baited hooks relatively rapidly (

The estimation of home range size of marine fish has received attention because of its application to the design of marine reserves. How individuals use space may also be important to the management of the species and for understanding behavioral processes like optimal foraging or ter- ritoriality. We used an acoustic tracking system (VRAP) to examine patterns in home range size and movement behavior for 3 demersal fishes in Puget Sound: lingcod Ophiodon elongatus, copper rock- fish Sebastes caurinus and quillback rockfish S. maliger. Data were collected over 8 wk in the sum- mer of 2006 and 3 wk in the winter of 2007. Home ranges were relatively small (~1500 to 2500 m 2 ) and did not differ among species. During the summer, lingcod had larger home ranges during the day than at night. Movement in all 3 species was in some way related to diel and tidal cycles, although individuals within species differed, and there was no general pattern. About half of the lingcod used portions of their home ranges only during the day and on the flood tide. Other individuals made sim- ilar movements on the ebb tide. Some copper rockfish moved to specific areas of their home range on the day ebb tide, while others made these movements on the night flood tide; others showed no pat- tern. Similar results were seen for quillback rockfish. While the arena of resource management often requires us to simplify complex systems, our results illustrate that such simplification may be difficult, and will depend ultimately on detailed behavioral data.

Our understanding of fish feeding interactions at Tijuana Estuary was improved by incorporating estimates of spatial and temporal variability into diet analyses. We examined the stomach contents of 7 dominant species (n=579 total fish) collected between 1994 and 1999. General feeding patterns pooled over time produced a basic food web consisting of 3 major trophic levels: (1) primary consumers (Atherinops affinis, Mugil cephalus) that ingested substantial amounts of plant material and detritus; (2) benthic carnivores (Clevelandia ios, Hypsopsetta guttulata, Gillichthys mirabilis, and Fundulus parvipinnis) that ingested high numbers of calanoid copepods and exotic amphipods (Grandidierella japonica); and (3) piscivores (Paralichthys californicus and Leptocottus armatus) that often preyed on smaller gobiids. Similarity-based groupings of individual species' diets were identified using nonmetric multidimensional scaling to characterize their variability within and between species, and in space and time. This allowed us identify major dietary shifts and recognize events (i.e., modified prey abundance during 1997–98 El Ni no floods) that likely caused these shifts.

The performance of two intertidal wetland mitigation projects constructed by the California Department of Transportation (Caltrans) in the Sweetwater Marsh National Wildlife Refuge (SMNWR) in San Diego Bay was evaluated over 5 years. Most of the Sweetwater wetland complex has been altered this century, including diking (with subsequent subsidence), filling, modification of the tidal regime, freshwater inflow and sediment fluxes. The mitigation project goals included a range of functional criteria intended to support two endangered bird species (light-footed clapper rail and California least tern) and one endangered plant (salt marsh bird's-beak). While the mitigation projects have achieved some of the performance criteria established in the regulatory permits (particularly, those related to fish), vegetation criteria for one of the bird species have not been met. The initial grading (in relation to local tidal datums) should support the target plant species, but growth has been less than required. Shortcomings of the habitat include elevated soil and groundwater salinity, low nutrient levels (especially nitrogen, which is readily leached from the coarse substrate), and eroding topography (where a single oversized and overly sinous channel and the lower-than-natural marshpalin result in high velocity surface water flow and erosion). The failure to achieve a large plain at low-marsh elevations highlights the importance of a more complete understanding of the relationship between the site physical processes (topography, hydrology, climate, geomorphology), substrate conditions, and biotic responses.

This study evaluated the use by fish of restored tidal wetlands and identified links between fish species composition and habitat characteristics. We compared the attributes of natural and constructed channel habitats in Sweetwater Marsh National Wildlife Refuge, San Diego Bay, California, by using fish monitoring data to explore the relationships between channel environmental characteristics and fish species composition. Fishes were sampled annually for 8 yr (1989–1996) at eight sampling sites, four in constructed marshes and four in natural marshes, using beach seines and blocking nets. We also measured channel habitat characteristics, including channel hydrology (stream order), width and maximum depth, bank slope, water quality (DO, temperature, salinity), and sediment composition. Fish colonization was rapid in constructed channels, and there was no obvious relationship between channel age and species richness or density. Total richness and total density did not differ significantly between constructed and natural channels, although California killifish (Fundulus parvipinnis) were found in significantly higher densities in constructed channels. Multivariate analyses showed fish assemblage composition was related to channel habitat characteristics, suggesting a channel’s physical properties were more important in determining fish use than its restoration status. This relationship highlights the importance of designing restoration projects with natural hydrologic features and choosing proper assessment criteria in order to avoid misleading interpretations of constructed channel success. We recommend that future projects be designed to mimic natural marsh hydrogeomorphology and diversity more closely, the assessment process utilize better estimates of fish habitat function (e.g., individual and community-based species trends, residence time, feeding, growth) and reference site choice, and experimental research be further incorporated into the restoration process.