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Management of protected species is difficult when objectives include the recovery of both predator and its prey. Ideally, identifying trade-offs between competing objectives involves evaluating management alternatives with a quantitative model that integrates information on both species, but data are often limited. We used new predator diet data and simulation modeling to update our understanding of seal predation on juvenile Chinook (Oncorhynchus tshawytscha) and coho salmon (Oncorhynchus kisutch) in the Puget Sound. Under prey size assumptions used by previous studies, estimates suggest predation could be a significant source of mortality for Chinook salmon (mean: 37% of ocean age-0 juveniles), but varied considerably among years (range of median estimates: 22%–49%). However, when we estimated prey size from otoliths recovered from seal scats, the impact (numbers of fish consumed) decreased by 71%. Predation on coho salmon was estimated to be relatively low under both scenarios (6%–8% of ocean age-0 juveniles) with a 21% decrease in consumption using otolith-derived prey size. Our analysis highlights the importance of updating model inputs and re-evaluating assumptions of multi-species models used for ecosystem-based fisheries management.

Efforts to understand causes of declines in productivity of species of concern often involve retrospective evaluation of multiple possible causes based on trends in relevant ecological indicators. We describe a hypothesis testing framework for examining declines in marine survival for coho and Chinook salmon in the Salish Sea. Independent populations of both anadromous species have declined over the last 50 years, prompting extensive examination of mortality in different life stages. Previous studies have identified declining trends in marine survival, and we re-evaluated these trends in light of a number of possible hypotheses for declines. We laid out seven potential explanations for declines: changes in predator buffering related to abundance and timing, density-dependent or -independent food availability, water quality, timing of freshwater delivery to Puget Sound, and anthropogenic impacts. We compiled ecosystem indicators relevant to these hypotheses and used generalized additive models (GAMs) to examine multivariate relationships with survival from multiple coho and Chinook salmon stocks. We also developed additional models using the most informative indicators based on variable importance weighting (VIW) from the seven hypothesis groups. We examined how these models explained overall trends in marine survival, as well as survival in three temporal stanzas (before, during, and after a major decline, based on statistical breakpoint analysis). Across the entire time series, best fitting models explained 30–40% of the variation in the survival data. Best fitting models were from multiple hypotheses, including predation (abundance and timing), competition, water quality, and anthropogenic impacts; the freshwater delivery hypothesis was the least supported. Different models performed best (lowest error) during different stanzas of the coho salmon marine survival time series and the two VIW models were generally the top performing models, but performance varied in different years. Indicators with the strongest support included seal abundance, herring abundance, timing of hatchery salmon releases, and indicators related to water properties like stratification and temperature. These findings suggest that multiple processes embedded in several of our hypotheses influence marine survival but that an ecological “smoking gun” for Salish Sea salmon declines will remain elusive.

Identifying factors that influence anadromous Pacific salmon (Oncorhynchus spp.) population dynamics is complicated by their diverse life histories and large geographic range. Over the last several decades, Chinook salmon (O. tshawytscha) populations from coastal areas and the Salish Sea have exhibited substantial variability in abundance. In some cases, populations within the Salish Sea have experienced persistent declines that have not rebounded. We analyzed a time series of early marine survival from 36 hatchery Chinook salmon populations spanning ocean entry years 1980–2008 to quantify spatial and temporal coherence in survival. Overall, we observed higher inter-population variability in survival for Salish Sea populations than non-Salish Sea populations. Annual survival patterns of Salish Sea populations covaried over smaller spatial scales and exhibited less synchrony among proximate populations relative to non-Salish Sea populations. These results were supported by multivariate autoregressive state space (MARSS) models which predominantly identified region-scale differences in survival trends between northern coastal, southern coastal, Strait of Georgia, and Puget Sound population groupings. Furthermore, Dynamic Factor Analysis (DFA) of regional survival trends showed that survival of southern coastal populations was associated with the North Pacific Gyre Oscillation, a large-scale ocean circulation pattern, whereas survival of Salish Sea populations was not. In summary, this study demonstrates that survival patterns in Chinook salmon are likely determined by a complex hierarchy of processes operating across a broad range in spatial and temporal scales, presenting challenges to the management of mixed-stock fisheries.

Social media platforms are effective tools used to help communicate and increase involvement in cultural, political, and scientific circles. In 2012, an ad hoc committee was established to explore online fisheries science communication and how social media platforms can be utilized by the American Fisheries Society (AFS). A survey was disseminated to all AFS units (chapters, sections, divisions) and student subunits to better understand the current use of social media within the AFS. A relatively high response rate (82%) provided some confidence in the survey results—namely, that nearly 69% or more of units and subunits used social media. Facebook was the dominant platform used (59%; all others < 15%) and almost exclusively (97%) for the purpose of communication. Education, outreach, and member recruitment were other reasons for social media use. Finally, whether units currently use social media or not at all, it was recommended that AFS-led workshops and assistance would increase the usefulness ...

Intense shading under large piers is known to negatively affect benthic fishes. However, effects on pelagic fishes are poorly known. We employed the equivalent of acoustic video, dual frequency identification sonar (DIDSON), under a kayak to evaluate the response of pelagic fishes at a large (351 × 255 m) urban pier (Pier 40) in Hudson River. A repeated measures design (322 occupations) sampled 3 transects each across both the northern and southern open water — pier edge — under pier continuum during the day and night from June 2009 to Septem- ber 2010. Over 22 000 individual fish, ranging from small schooling forage species (e.g. Anchoa mitchilli, Menidia menidia) to large predators (Morone saxatilis, Pomatomus saltatrix) were detected with DIDSON and verified with conventional sampling nets. Small ( 250 mm) predatory fish responded somewhat differently from small schooling fish in that large predatory fish were slightly more abundant under the pier than in open water, but only from the edge extending to 5 m under the pier where there was still some light. Beyond that, abundance declined sharply. Together, these observations indicate that areas under large piers are suboptimal habitats for many of the abundant pelagic fishes, a pattern similar to that for benthic fishes.

A new species of the teleostean family Sternoptychidae, Polyipnus notatus n. sp. , is described based on material collected mainly off Taiwan in the South China Sea. The new species is most similar to P. triphanos , based on the presence of a single posttemporal spine, lack of scale spination, and the second and third ACA (=supra-anal) photophores elevated relative to the first and connected to each other in a common organ. These characters typify other members of the P. asteroides species group that occur in various tropical to temperate ocean basins. Based on a limited sample of 27 specimens, P. notatus (maximum observed size 30.7 mm SL) appears to be smaller than most other congeners. It is also characterized by an unusual lateral pigment bar, which is narrow and distinctly triangular. Based on the material examined, the geographical distribution of the species appears to be restricted to the South China Sea and adjacent minor ocean basins.