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Identifying patterns of organismal distribution can provide valuable insights for basic and applied marine and coastal ecology because understanding where animals are located is foundational to both research and science-based conservation. Understanding variation in distributional patterns can lead to a better assessment of ecological drivers and an improved ability to predict consequences of natural and altered relationships. Here, our purpose is to explore if quantifying coexisting groups of individual fish predators advances our understanding of field distribution patterns. Toward this end, we quantified locations of 59 acoustically tagged striped bass (Morone saxatilis) within a 26-stationary unit telemetry receiver array in Plum Island Estuary (PIE), MA, United States. We then used cluster analyses on spatial and temporal-spatial metrics from this dataset to (1) assess if distinct groups of individuals coexisted, (2) quantify group characteristics, and (3) test associations between groups and distribution (e.g., physical site type and region). Based on multiple lines of evidence, we identified four groups of striped bass with different space use patterns that persisted across seasons (summer and fall). Similar-sized striped bass clustered at spatial and temporal scales at which individuals within distinct groups could, and did, physically overlap. In addition, distributional groups were linked to components of physical site type and region suggesting that discrete groups of individuals can interact differently with the environment within the same ecological system. The identification of these distinct groups of individuals creates a baseline from which to explore further ecological implications of grouping behavior for research and conservation in geographically large, temporally dynamic, and spatially heterogeneous marine and coastal environments.

Connecting individual datasets from different projects to each other and to decisions can help manager-researcher-administrator teams link existing information and adapt their environmental decision-making process as new information becomes available. Throughout their careers, environmental professionals often collect data on many individual projects that address similar sets of natural resource conservation problems. Consequently, the institutions, agencies, and organizations that employ these environmental professionals accumulate a large reservoir of project-specific information. However, opportunities to advance broader natural resource conservation goals are lost if individual projects and datasets are not integrated. Here we illustrate how adaptive problem mapping (APM) provides a framing and internal structure that charts relationships among pertinent information types, germane data sets, applicable concepts, and relevant decisions. In the APM process, appropriately defined problem statements and coordinated bridging questions connect data and concepts to build a network of increasingly informed and defensible decisions. Although APM can be applied to many environmental problems, we focus on examples from aquatic systems in which fish are conservation priorities. Prioritizing an initial evaluation and regular modification of the relationships among datasets and decisions using the APM process helps manager-researcher-administrator teams envision, track, and update what is known, unknown, learned, and needed. The resulting broader point of view advances strategic planning, evaluations of progress, assessments of opportunity costs, identification of options, and justifications of decision-related actions.

Tagging protocols that result in high tag retention will benefit fisheries professionals who use telemetry data. Ictalurid catfish historically have had very poor telemetry tag retention. Here, we use these difficult-to-tag taxa to address two research objectives. First, we evaluated our field-based internal tagging methodology by quantifying six tag retention metrics using data from 48 acoustically-tagged blue catfish (Ictalurus furcatus) released into Milford Reservoir, KS, USA. Second, to better understand the results of this field evaluation, we evaluated tag retention and survival in the hatchery for the closely-related channel catfish (I. punctatus). Field and hatchery studies provided complementary information. Eighty percent of tagged blue catfish were detected at the end of our 5-mo field study (1,139,402 = total detections; 24,243 = average detections per fish). A 13-week hatchery evaluation of our field methodology also had high tag retention (100%). Hatchery treatments that used a lateral-ventral incision had higher tag retention and survival than those treatments that included a mid-ventral incision. Time invested in training, protocol refinement, and field organization were also important. Furthermore, monitoring the surgical history and recovery of individual fish allowed us to correct problems before mortality occurred. Because a need exists for a range of internal tagging methodologies that are effective on an assortment of fish species tagged under a variety of circumstances, our high tag retention methodology may be useful to the expanding research community that studies native and non-native catfish, as well as, other telemetry researchers who seek beneficial refinements to their tagging protocols.

Science has played a mixed role in guiding conservation and sustainability-oriented decision-making by individuals, policymakers, institutions, and governments. Not all science-based conservation and sustainability initiatives that address issues facing humanity and ecosystems and global problems have gained public support. Conservation decisions and policy prescriptions are and may be based on perceptions about and experiences with the environment, local land use, and ecosystems that may not align with or be grounded in science or evidence from experts in the field. Values, beliefs, and perceptions associated with nature play a critical role in how individuals view biodiversity conservation, sustainability, and natural resource management. This study first examines the gap between experts (scientists and other field experts) and the public (farmers and non-farmers) about the state of water and land resources, wildlife and associated habitats, and aquatic biodiversity in the Smoky Hill River Watershed in western Kansas. Second, the study examines the role that values and beliefs play in shaping environmental perceptions for farmers and non-farmers. Analysis confirms that a gap between experts and farmers/non-farmers does exist, especially with respect to the state of the Ogallala Aquifer, playas, rivers and streams, lakes and reservoirs, native grasslands, wildlife habitats, farmland, native fish populations, and wildlife species. Ordered-logistic regression analyses, meanwhile, indicate that farmer and non-farmer perceptions about the state of the local environment are influenced by traditional and self-interested values, as well as environmental values and beliefs, but less so by religiosity and political ideology. Despite broad takeaways, results exhibited heterogeneity across the farmer and non-farmer subpopulations. If environmental professionals cannot align ecological data, stakeholders' values/perceptions, and policies, then the existing body of technical research and management on sustainability in natural and social sciences may be of little value.

Agricultural landscapes are the leading edge in the advancement of sustainability and climate change adaptation. The purpose of this study is to endogenize culture as shaped by natural-cultural feedback into individuals’ decision-making processes on sustainability policy support. We present an agent-based model in which an adaptive cultural decision-rule quantifies the probability of an agent deciding to support a wildlife area policy for the Smoky Hill River Watershed (SHRW) in Kansas, USA. By using an ABM to examine the watershed as a coupled natural and human system, we learned that agents would adopt a new behavior, voting for the policy, if the cultural conditions were right, with high levels of beliefs and norms for freshwater and its biota. Our results indicate that individuals in the SHRW are not engaged in caring for fish, plants, and bird richness in their rivers and playas with few individuals supporting the policy in the naive cultural setting (8.9 % of simulated population). However, enough agents would support the policy under a lower cultural threshold (40.7 % of simulated population). Our results show that sustainability policies need to account for the local culture to gain support, and if a policy is culturally meaningful, it does not need to be cheap. For an agricultural landscape, such as those commonly found in the Central Great Plains, this study presents new levers for policymakers on the conditions needed to help assemble popular support for sustainability policies.

Conserving native biodiversity depends on restoring functional habitats in the face of human-induced disturbances. Low-head dams are a ubiquitous human impact that degrades aquatic ecosystems worldwide. To improve our understanding of how low-head dams impact habitat and associated biodiversity, our research examined complex interactions among three spheres of the total environment. i.e., how low-head dams (anthroposphere) affect aquatic habitat (hydrosphere), and native biodiversity (biosphere) in streams and rivers. Creation of lake-like habitats upstream of low-head dams is a well-documented major impact of dams. Alterations downstream of low head dams also have important consequences, but these downstream dam effects are more challenging to detect. In a multidisciplinary field study at five dammed and five undammed sites within the Neosho River basin, KS, we tested hypotheses about two types of habitat sampling (transect and mosaic) and two types of statistical analyses (analysis of covariance and path analysis). We used fish as our example of biodiversity alteration. Our research provided three insights that can aid environmental professionals who seek to conserve and restore fish biodiversity in aquatic ecosystems threatened by human modifications. First, a mosaic approach identified habitat alterations below low-head dams (e.g. increased proportion of riffles) that were not detected using the more commonly-used transect sampling approach. Second, the habitat mosaic approach illustrated how low-head dams reduced natural variation in stream habitat. Third, path analysis, a statistical approach that tests indirect effects, showed how dams, habitat, and fish biodiversity interact. Specifically, path analysis revealed that low-head dams increased the proportion of riffle habitat below dams, and, as a result, indirectly increased fish species richness. Furthermore, the pool habitat that was created above low-head dams dramatically decreased fish species richness. As we show here, mosaic habitat sampling and path analysis can help conservation practitioners improve science-based management plans for disturbed aquatic systems worldwide.

Conserving native biodiversity in the face of human- and climate-related impacts is a challenging and globally important ecological problem that requires an understanding of spatially-connected, organismal-habitat relationships. Globally, a suite of disturbances (e.g., agriculture, urbanization, climate change) degrades habitats and threatens biodiversity. A mosaic approach (in which connected, interacting collections of juxtaposed habitat patches are examined) provides a scientific foundation for addressing many disturbance-related, ecologically-based conservation problems. For example, if specific habitat types disproportionately increase biodiversity, these keystones should be incorporated into research and management plans. Our sampling of fish biodiversity and aquatic habitat along ten 3-km sites within the Upper Neosho River sub-drainage, KS, from June-August 2013 yielded three generalizable ecological insights. First, specific types of mesohabitat patches (i.e., pool, riffle, run, and glide) were physically distinct and created unique mosaics of mesohabitats that varied across sites. Second, species richness was higher in riffle mesohabitats when mesohabitat size reflected field availability. Furthermore, habitat mosaics that included more riffles had greater habitat diversity and more fish species. Thus, riffles (

Telemetry can inform many scientific and research questions if a context exists for integrating individual studies into the larger body of literature. Creating cumulative distributions of post-tagging evaluation metrics would allow individual researchers to relate their telemetry data to other studies. Widespread reporting of standard metrics is a precursor to the calculation of benchmarks for these distributions (e.g., mean, SD, 95% CI). Here we illustrate five types of standard post-tagging evaluation metrics using acoustically tagged Blue Catfish (Ictalurus furcatus) released into a Kansas reservoir. These metrics included: (1) percent of tagged fish detected overall, (2) percent of tagged fish detected daily using abacus plot data, (3) average number of (and percent of available) receiver sites visited, (4) date of last movement between receiver sites (and percent of tagged fish moving during that time period), and (5) number (and percent) of fish that egressed through exit gates. These metrics were calculated for one to three time periods: early ( 5 days early in the study. On average, tagged Blue Catfish visited 9 (50%) and 13 (72%) of 18 within-reservoir receivers early and at the end of the study, respectively. At the end of the study, 73% of all tagged fish were detected moving between receivers. Creating statistical benchmarks for individual metrics can provide useful reference points. In addition, combining multiple metrics can inform ecology and research design. Consequently, individual researchers and the field of telemetry research can benefit from widespread, detailed, and standard reporting of post-tagging detection metrics.

Quantifying physical heterogeneity is essential for meaningful ecological research and effective resource management. Spatial patterns of multiple, co-occurring physical features are rarely quantified across a seascape because of methodological challenges. Here, we identified approaches that measured total site-specific heterogeneity, an often overlooked aspect of estuarine ecosystems. Specifically, we examined 23 metrics that quantified four types of common physical features: (1) river and creek confluences, (2) bathymetric variation including underwater drop-offs, (3) land features such as islands/sandbars, and (4) major underwater channel networks. Our research at 40 sites throughout Plum Island Estuary (PIE) provided solutions to two problems. The first problem was that individual metrics that measured heterogeneity of a single physical feature showed different regional patterns. We solved this first problem by combining multiple metrics for a single feature using a within-physical feature cluster analysis. With this approach, we identified sites with four different types of confluences and three different types of underwater drop-offs. The second problem was that when multiple physical features co-occurred, new patterns of total site-specific heterogeneity were created across the seascape. This pattern of total heterogeneity has potential ecological relevance to structure-oriented predators. To address this second problem, we identified sites with similar types of total physical heterogeneity using an across-physical feature cluster analysis. Then, we calculated an additive heterogeneity index, which integrated all physical features at a site. Finally, we tested if site-specific additive heterogeneity index values differed for across-physical feature clusters. In PIE, the sites with the highest additive heterogeneity index values were clustered together and corresponded to sites where a fish predator, adult striped bass (Morone saxatilis), aggregated in a related acoustic tracking study. In summary, we have shown general approaches to quantifying site-specific heterogeneity.

Sustainability has been at the forefront of the environmental research agenda of the integrated anthroposphere, hydrosphere, and biosphere since the last century and will continue to be critically important for future environmental science. However, linking humans and the environment through effective policy remains a major challenge for sustainability research and practice. Here we address this gap using an agent-based model (ABM) for a coupled natural and human systems in the Smoky Hill River Watershed (SHRW), Kansas, USA. For this freshwater-dependent agricultural watershed with a highly variable flow regime influenced by human-induced land-use and climate change, we tested the support for an environmental policy designed to conserve and protect fish biodiversity in the SHRW. We develop a proof of concept interdisciplinary ABM that integrates field data on hydrology, ecology (fish richness), social-psychology (value-belief-norm) and economics, to simulate human agents' decisions to support environmental policy. The mechanism to link human behaviors to environmental changes is the social-psychological sequence identified by the value-belief-norm framework and is informed by hydrological and fish ecology models. Our results indicate that (1) cultural factors influence the decision to support the policy; (2) a mechanism modifying social-psychological factors can influence the decision-making process; (3) there is resistance to environmental policy in the SHRW, even under potentially extreme climate conditions; and (4) the best opportunities for policy acceptance were found immediately after extreme environmental events. The modeling approach presented herein explicitly links biophysical and social science has broad generality for sustainability problems.

This chapter discusses an interdisciplinary and transdisciplinary project to understand the interactions of agriculture, climate, and water resources in the Central Great Plains as a coupled natural-human system. We focus on the Smoky Hills Watershed in Kansas, where we gathered socioeconomic, hydrological, and climatic data, along with ecological data on fish species. The project involved substantial stakeholder engagement, which was complicated by post-truth attitudes about climate science and environmental regulation by some groups. We discuss the challenges of team management, stakeholder engagement, and data integration for modeling, notably the incorporation of stakeholder support for environmental policy in the context of extreme climatic events. We conclude by offering a framework for good collaborative practice to manage the complications of crossing boundaries in transdisciplinary research and outreach.

Natural resource professionals have frequently criticized universities for poorly preparing graduates to succeed in their jobs. We surveyed members of the American Fisheries Society to determine which job skills and knowledge of academic topics employers, students, and university faculty members deemed most important to early-career success of fisheries professionals. Respondents also rated proficiency of recently hired, entry-level professionals (employers) on how well their programs prepared them for career success (students and faculty) in those same job skills and academic topics. Critical thinking and written and oral communication skills topped the list of important skills and academic topics. Employers perceived recent entry-level hires to be less well-prepared to succeed in their careers than either university faculty or students. Entry-level hires with post-graduate degrees rated higher in proficiency for highly important skills and knowledge than those with bachelor's degrees. We conclude that a...

Most anadromous fish populations remain at low levels or are in decline despite substantial investments in restoration. We explore whether a resilience perspective (i.e., a different paradigm for understanding populations, communities, and ecosystems) is a viable alternative framework for anadromous fish restoration. Many life history traits have allowed anadromous fish to thrive in unimpacted ecosystems but have become contemporary curses as anthropogenic effects increase. This contradiction creates a significant conservation challenge but also makes these fish excellent candidates for a resilience approach. A resilience approach recognizes the need to maintain life history, population, and habitat characteristics that increase the ability of a population to withstand and recover from multiple disturbances. To evaluate whether a resilience approach represents a viable strategy for anadromous fish restoration, we review four issues: (1) how resilience theory can inform anadromous fish restoration, (2) how...

Dams are ubiquitous environmental impacts that threaten aquatic ecosystems. The ability to compare across research studies is essential to conserve the native biodiversity that is impacted by the millions of low-head dams that currently fragment streams and rivers. Here, we identify a previously unaddressed obstacle that impedes this generalization. Specifically, divergent spatial and taxonomic approaches that result from different conceptualizations of the dam-biodiversity problem can produce conflicting science-based conclusions about the same dam impact. In this research, using the same dammed and undammed sites, we evaluated the scientific generality of different conceptualizations of the dam-biodiversity problem. We compared two different but commonly used spatial approaches—(1) above dam–below dam vs. (2) undammed–dammed comparisons—and 11 different, commonly used taxonomic approaches (three assemblage summaries, eight guilds). Sites above the dam structure had less diverse fish assemblages than sites below dams, whereas sites below the dam structure were similar to undammed sites. Thus, spatial approach 1 detected a large dam effect and spatial approach 2 detected a small dam effect. Similarly, some taxonomic responses (species richness, diversity, abundance, and number of guilds) detected large dam effects; other responses detected small (riffle specialist guild) or no dam effects (pool generalists). In summary, our results showed that how the problem was framed altered scientific conclusions and created different dam realities. The metaphor of how individual blind men disagree about the structure of an elephant, based on examinations of different body parts, reinforces the need for a coordinated, holistic perspective on dam research. Although no single approach is adequate for all problems, identifying the form, consequences of, and relationships among different research conceptualizations will set the stage for future syntheses of dam-biodiversity research to advance science-based conservation.

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Because human impacts and climate change threaten aquatic ecosystems, a need exists to quantify catchment-scale biodiversity patterns and identify conservation actions that can mitigate adverse human impacts on aquatic biota. Whereas many traditional aquatic resource questions can be answered by repeatedly sampling a few target species with limited types of gear in the same habitats, sampling fish biodiversity patterns at larger scales requires a different approach. Researchers and managers need to determine the types of sampling gear and amount of effort that provide a representative estimate of biodiversity in a range of habitats across a catchment. Using a randomized block design within a 90-m stream reach that contained the same habitats as the scientific study area, fish assemblages were compared using three different types of gear (minnow traps, backpack electrofishing, and hoop nets) at three levels of effort (one, two, and three mixed-gear units) over four replicate days. A mixture of gear types best quantified fish assemblages. A combination of 10 minnow traps, 20-m of backpack electrofishing, and two hoop nets caught the most species. Additional gear added few new species. Resampling confirmed these results. When researchers and managers initiate sampling on a new stream or river system, they do not know how effective each gear type is and whether their sampling effort is adequate. Although the types and amount of gear may be different for other studies, systems, and research questions, the five-step process described here for making sampling decisions and evaluating sampling efficiency can be applied widely to any system to restore, manage, and conserve aquatic ecosystems. It is believed that incorporating this gear-evaluation process into a wide variety of studies and ecosystems will increase rigour within and across aquatic biodiversity studies. Copyright © 2013 John Wiley & Sons, Ltd.

Integrating the analysis of natural and social systems to achieve sustainability has been an international scientific goal for years (1, 2). However, full integration has proven challenging, especially in regard to the role of culture (3), which is often missing from the complex sustainability equation. To enact policies and practices that can achieve sustainability, researchers and policymakers must do a better job of accounting for culture, difficult though this task may be.

During recent human history, human activities such as overhunting and habitat destruction have severely impacted many large top predator populations around the world. Studies from a variety of ecosystems show that loss or diminishment of top predator populations can have serious consequences for population and community dynamics and ecosystem stability. However, there are relatively few studies of the roles of large top predators in coastal ecosystems, so that we do not yet completely understand what could happen to coastal areas if large top predators are extirpated or significantly reduced in number. This lack of knowledge is surprising given that coastal areas around the globe are highly valued and densely populated by humans, and thus coastal large top predator populations frequently come into conflict with coastal human populations. This paper reviews what is known about the ecological roles of large top predators in coastal systems and presents a synthesis of recent work from three coastal eastern US Long Term Ecological Research (LTER) sites where long-term studies reveal what appear to be common themes relating to the roles of large top predators in coastal systems. We discuss three specific themes: (1) large top predators acting as mobile links between disparate habitats, (2) large top predators potentially affecting nutrient and biogeochemical dynamics through localized behaviors, and (3) individual specialization of large top predator behaviors. We also discuss how research within the LTER network has led to enhanced understanding of the ecological roles of coastal large top predators. Highlighting this work is intended to encourage further investigation of the roles of large top predators across diverse coastal aquatic habitats and to better inform researchers and ecosystem managers about the importance of large top predators for coastal ecosystem health and stability.

The paucity of data on migratory connections and an incomplete understanding of how mobile organisms use geographically separate areas have been obstacles to understanding coastal dynamics. Research on acoustically tagged striped bass (Morone saxatilis) at the Plum Island Ecosystems (PIE) Long Term Ecological Research site, Massachusetts, documents intriguing patterns of biotic connectivity (i.e., long-distance migration between geographically distinct areas). First, the striped bass tagged at PIE migrated southward along the coast using different routes. Second, these tagged fish exhibited strong fidelity and specificity to PIE. For example, across multiple years, tagged striped bass resided in PIE waters for an average of 1.5–2.5 months per year (means: 51–72 days; range 2–122 days), left this estuary in fall, then returned in subsequent years. Third, this specificity and fidelity connected PIE to other locations. The fish exported nutrients and energy to at least three other coastal locations through biomass added as growth. These results demonstrate that what happens in an individual estuary can affect other estuaries. Striped bass that use tightly connected routes to feed in specific estuaries should have greater across-system impacts than fish that are equally likely to go anywhere. Consequently, variations in when, where, and how fish migrate can alter across-estuary impacts.

Summary Understanding the relationship between heterogeneity and biodiversity is an active focus of ecological research. Although habitat heterogeneity is conceptually linked to biodiversity, the amount and configuration of heterogeneity that maintains biodiversity within ecosystems is not well understood, especially for an entire stream network. Here, we tested alternative outcomes about how habitat alterations caused by beaver dams affected native fish biodiversity. Specifically, we quantified in-stream habitat and fish assemblages above and below all beaver dams (n = 15) and selected control sites (n = 9), adjacent to beaver dams, within an entire, low-gradient stream network (Fish Brook, MA, U.S.A.). Beaver dams altered habitat within streams in four ways based on upstream versus downstream differences in stream width, depth, velocity and substratum. In general, habitat heterogeneity, measured using two indices, was greater at beaver dams than control sites. The diversity and abundance of fish around beaver dams were positively related to habitat heterogeneity. Faster water and the coarser substratum below beaver dams increased the amount of fluvial habitat available to native fish. This alteration can be critical for fish with life histories that depend on flowing water and hard substrata. In summary, within a stream network, beaver dams maintained fish biodiversity by altering in-stream habitat and increasing habitat heterogeneity. Understanding the relationship between habitat heterogeneity and biodiversity can advance basic freshwater ecology and provide science-based support for applied aquatic conservation.

Citation: Kennedy, C. G., Mather, M. E., Smith, J. M., Finn, J. T., & Deegan, L. A. (2016). Discontinuities concentrate mobile predators: quantifying organism-environment interactions at a seascape scale. Ecosphere, 7(2), 17. doi:10.1002/ecs2.1226

Ecological indicators are science-based tools used to assess how human activities have impacted environmental resources. For monitoring and environmental assessment, existing species assemblage data can be used to make these comparisons through time or across sites. An impediment to using assemblage data, however, is that these data are complex and need to be simplified in an ecologically meaningful way. Because multivariate statistics are mathematical relationships, statistical groupings may not make ecological sense and will not have utility as indicators. Our goal was to define a process to select defensible and ecologically interpretable statistical simplifications of assemblage data in which researchers and managers can have confidence. For this, we chose a suite of statistical methods, compared the groupings that resulted from these analyses, identified convergence among groupings, then we interpreted the groupings using species and ecological guilds. When we tested this approach using a statewide stream fish dataset, not all statistical methods worked equally well. For our dataset, logistic regression (Log), detrended correspondence analysis (DCA), cluster analysis (CL), and non-metric multidimensional scaling (NMDS) provided consistent, simplified output. Specifically, the Log, DCA, CL-1, and NMDS-1 groupings were ≥60% similar to each other, overlapped with the fluvial-specialist ecological guild, and contained a common subset of species. Groupings based on number of species (e.g., Log, DCA, CL and NMDS) outperformed groupings based on abundance [e.g., principal components analysis (PCA) and Poisson regression]. Although the specific methods that worked on our test dataset have generality, here we are advocating a process (e.g., identifying convergent groupings with redundant species composition that are ecologically interpretable) rather than the automatic use of any single statistical tool. We summarize this process in step-by-step guidance for the future use of these commonly available ecological and statistical methods in preparing assemblage data for use in ecological indicators.

After centuries of disturbance, environmental professionals now recognize the need to restore coastal watersheds for native fish and protect the larger ecosystems on which fish and other aquatic biota depend. Anadromous fish species are an important component of coastal ecosystems that are often adversely affected by human activities. Restoring native anadromous fish species is a common focus of both fish and coastal watershed restoration. Yet restoration efforts have met with uneven success, often due to lack of knowledge about habitat availability and use. Using habitat surveys and radio tracking of adult anadromous alewives Alosa pseudoharengus during their spring spawning migration, we illustrate a method for quantifying habitat using multiple approaches and for relating mobile fish distribution to habitat. In the Ipswich River, Massachusetts, measuring habitat units and physical conditions at transects (width, depth, and velocity) provided an ecological basis for the interpretation of landsc...

Subadult and small adult (375–475 mm total length) striped bass Morone saxatilis are abundant and represent an important component of the recovered U.S. Atlantic coast stocks. However, little is known about these large aggregations of striped bass during their annual foraging migrations to New England. A quantitative understanding of trends in the diets of subadult and small adult migrants is critical to research and management. Because of the complexity of the Massachusetts coast, we were able to compare diets at multiple spatial, temporal, and taxonomic scales and evaluate which of these provided the greatest insights into the foraging patterns of this size of fish. Specifically, during spring through autumn, we quantified the diets of 797 migratory striped bass collected from 13 Massachusetts estuaries distributed among three geographic regions in two biogeographic provinces. Our data provided three useful results. First, subadult and young adult striped bass ate a season-specific mixture of f...

Almost three-quarters of the 46 young adult and sub-adult striped bass Morone saxatilis that were acoustically tagged in Plum Island Estuary, Massachusetts, U.S.A., in the summer of 2006 were detected in one or more southern coastal arrays during their autumn migration. On the basis of the trajectories along which these M. saxatilis moved from feeding to overwintering areas, three migratory groups emerged. After leaving Plum Island Estuary, about half of the fish were detected only in a mid-latitude array, Long Island Sound. The other half of the tagged fish were detected during autumn and winter in a more southern array, the Delaware Estuary. This latter group of fish may have used two routes. Some travelled to the Delaware Estuary through Long Island Sound while other fish may have taken a second, more direct, coastal route that did not include Long Island Sound. Consequently, a seemingly homogeneous group of fish tagged at the same time in the same non-natal feeding location exhibited a diversity of southward movement patterns that could affect population-level processes. These three groups that differed in overwintering location and migration route could be movement contingents with migratory connectivity.

Capturing adult anadromous fish that are ready to spawn from a self sustaining population and transferring them into a depleted system is a common fisheries enhancement tool. The behaviour of these transplanted fish, however, has not been fully evaluated. The movements of stocked and native anadromous alewife, Alosa pseudoharengus (Wilson), were monitored in the Ipswich River, Massachusetts, USA, to provide a scientific basis for this management tool. Radiotelemetry was used to examine the effect of origin (native or stocked) and release location (upstream or downstream) on distribution and movement during the spawning migration. Native fish remained in the river longer than stocked fish regardless of release location. Release location and origin influenced where fish spent time and how they moved. The spatial mosaic of available habitats and the entire trajectory of freshwater movements should be considered to restore effectively spawners that traverse tens of kilometres within coastal rivers.

Using acoustic telemetry on migratory striped bass Morone saxatilis in Plum Island Estuary (PIE), Massachusetts, we found that striped bass (335–634 mm total length) tagged in the spring and summer of 2005 (n = 14) and 2006 (n = 46) stayed in the estuary for an average of 66.0 d in 2005 and 72.2 d in 2006. Striped bass spent the most time in two specific reaches: middle Plum Island Sound and lower Rowley River. In both years, three different use-groups of striped bass were observed in PIE. Short-term visitors (n = 24) stayed in the estuary only briefly (range = 5–20 d). Two groups of seasonal residents stayed for more than 30 d, either in the Rowley River (n = 14) or in Plum Island Sound (n = 22). Within PIE, the two seasonal-resident use-groups may be foraging contingents that learn how to feed efficiently in specific parts of the estuary. These distinct within-estuary use patterns could have different implications for striped bass condition and prey impact.

Recent changes in the landscape of scientific publishing prompted the Publications Overview Committee of the American Fisheries Society (AFS) to review the Society's portfolio of scientific journals. We evaluated journals based on metrics in two categories: (1) citation-based measures of the influence of a journal on the scientific literature, and (2) measures of the cost-effectiveness of a journal (citation rate adjusted for subscription cost). Over the long-term, we found that ecology journals had far stronger citation-based influence than fisheries and aquatic sciences journals, and that journals publishing primarily basic research had stronger influence than journals publishing applied research (including four AFS journals and Fisheries magazine). In evaluating the current status of fisheries and aquatic sciences journals, we found that metrics of influence and cost-effectiveness provided considerably different portrayals of journals relative to their peers. In terms of citation-based influence, we found that the AFS journal Transactions of the American Fisheries Society (TAFS) and Fisheries magazine were competitive with highly regarded peer fisheries journals, but that North American Journal of Aquaculture (NAJA) and Journal of Aquatic Animal Health (JAAH) were less influential than their peers. The citation-based influence of North American Journal of Fisheries Management (NAJFM) was intermediate between TAFS/Fisheries and NAJA/JAAH. For journals like NAJFM and NAJA, we expect that much of the scientific influence on policy and management is not captured by citations in the primary literature, and alternative methods of evaluation may be needed. All of the AFS journals ranked highly with regard to cost-effectiveness because their subscription costs are low, and these rankings are in accordance with membership needs and the strategic mission of AFS to provide broad and timely dissemination of scientific information. We conclude by suggesting ways to increase the influence of AFS journals without compromising their accessibility and affordability, and offer advice about methods and frequency for future journal evaluations.

Successful conservation depends on a scientifically literate public. We developed the Adopt-A-Herring program to educate nonscientists about fisheries and watershed restoration. This interactive educational and outreach project encouraged coastal residents to be involved in local watershed restoration. In the northeastern United States, river herring (Alosa spp.) are an important component of many coastal watersheds and often are the object of conservation efforts. In order to understand river herring spawning behavior and to improve the effectiveness of restoration efforts, our research tracked these fish via radiotelemetry in the lpswich River, Massachusetts. In our Adopt-A-Herring Program, participating stakeholder organizations adopted and named individual tagged river herring and followed their movements online. We also made information available to our adopters on our larger research goals, the mission and activities of other research and management agencies, examples of human actions that ...

Telemetry has allowed researchers to document the upstream migrations of anadromous fish in freshwater. In many anadromous alosine telemetry studies, researchers use downstream movements (“fallback”) as a behavioral field bioassay for adverse tag effects. However, these downstream movements have not been uniformly reported or interpreted. We quantified movement trajectories of radio-tagged anadromous alewives (Alosa pseudoharengus) in the Ipswich River, Massachusetts (USA) and tested blood chemistry of tagged and untagged fish held 24 h. A diverse repertoire of movements was observed, which could be quantified using (a) direction of initial movements, (b) timing, and (c) characteristics of bouts of coupled upstream and downstream movements (e.g., direction, distance, duration, and speed). Because downstream movements of individual fish were almost always made in combination with upstream movements, these should be examined together. Several of the movement patterns described here could fall under the traditional definition of “fallback” but were not necessarily aberrant. Because superficially similar movements could have quite different interpretations, post-tagging trajectories need more precise definitions. The set of metrics we propose here will help quantify tag effects in the field, and provide the basis for a conceptual framework that helps define the complicated behaviors seen in telemetry studies on alewives and other fish in the field.

– Variation in fish abundance across systems presents a challenge to our understanding of fish populations because it limits our ability to predict and transfer basic ecological principles to applied problems. Yellow perch (Perca flavescens) is an ideal species for exploring environmental and biotic correlates across system because it is widely distributed and physiologically tolerant. In 16 small, adjacent systems that span a wide range of environmental and biotic conditions, yellow perch were sampled with a standard suite of gear. Water quality, morphometry, vegetation, invertebrates and fish communities were concurrently measured. Multimodel inference was used to prioritise regressors for the entire yellow perch sample and three size groups (35–80, 81–180, ≥181 mm TL). Across systems, pH and fish richness were identified as the key drivers of yellow perch abundance. At very low pH ( 4.8) had many other species and few yellow perch. Similar patterns for pH and fish community were observed for the two largest-size classes. Negative interactions were observed between the medium- and large-sized yellow perch and between the largest and smallest yellow perch, although interspecific interactions were weaker than expected. This examination of variability for an indicator species and its component-size classes provides ecological understanding that can help frame the larger-scale sampling programs needed for the conservation of freshwater fish.

1. To conserve biodiversity in a human-dominated landscape, a science-based inventory and monitoring plan is needed that quantifies existing resources, isolates drivers that maintain natural communities, determines harmful stressors, and links ecological drivers and human stressors. A tactical approach is proposed for conservation planning using freshwater fish at the Cape Cod National Seashore. 2. Freshwater fish are well studied and occur across environmental gradients. The lentic systems at the national park are relatively pristine yet are enveloped by a region of high population density. Using fish community data, three steps were taken for tracking anthropogenic impacts in a human dominated landscape. First, fish and potential drivers were sampled intensively along a gradient to determine which fish metrics reflect natural communities and which abiotic and biotic factors structure them. Second, emerging and existing regional human threats were identified. Third, these human threats were linked to the potential drivers that maintain natural communities to identify the most informative metrics to monitor and track change. 3. Fish communities, water quality, habitat, and food resources were sampled concurrently in 18 ponds in 1999 and 2000. Three common fish species explained 98% of variation in numbers across systems. Based on ecological relationships, pH, depth, vegetation, prey, and community complexity were determined to maintain biodiversity of freshwater fish communities. 4. The primary human threats here included: development-related, land-use changes; non-point source pollution; eutrophication from septic systems; and introduced species that are a byproduct of high human visitation. These are common threats in many rapidly urbanized areas and are likely to have relevance to many sites. 5. To track the impact of emerging threats to freshwater ponds related to increased human population, monitoring changes in water quality, vegetated habitat, fish diversity, and trophic interactions are recommended. Copyright © 2008 John Wiley & Sons, Ltd.

In the last 25 years, the number and scope of fish-related journals have changed. New and existing journals are increasingly specialized. Journals that are read and cited are changing because of differential accessibility via electronic databases. In this review, we examine shifts in numbers and foci of existing fish-related journals. We ask how these fish-related metrics differ across type of application, ecological system, taxa, and discipline. Although many journals overlap to some extent in content, there are distinct groups of journals for authors to consider. By systematically reviewing the focus of an individual manuscript, comparing it to the suite of journals available and examining the audience for the manuscript, we believe that authors can make informed decisions about which journals are most suitable for their work. Our goal here is to help authors find relevant journals and deliver scientific publications to the appropriate readership.

Temperature is important to fish in determining their geographic distribution. For cool- and cold-water fish, thermal regimes are especially critical at the southern end of a species’ range. Although temperature is an easy variable to measure, biological interpretation is difficult. Thus, how to determine what temperatures are meaningful to fish in the field is a challenge. Herein, we used the Connecticut River as a model system and Atlantic salmon (Salmo salar) as a model species with which to assess the effects of summer temperatures on the density of age 0 parr. Specifically, we asked: (1) What are the spatial and temporal temperature patterns in the Connecticut River during summer? (2) What metrics might detect effects of high temperatures? and (3) How is temperature variability related to density of Atlantic salmon during their first summer? Although the most southern site was the warmest, some northern sites were also warm, and some southern sites were moderately cool. This suggests localized, within basin variation in temperature. Daily and hourly means showed extreme values not apparent in the seasonal means. We observed significant relationships between age 0 parr density and days at potentially stressful, warm temperatures (≥23°C). Based on these results, we propose that useful field reference points need to incorporate the synergistic effect of other stressors that fish encounter in the field as well as the complexity associated with cycling temperatures and thermal refuges. Understanding the effects of temperature may aid conservation efforts for Atlantic salmon in the Connecticut River and other North Atlantic systems.

Longitudinal connectivity is a fundamental characteristic of rivers that can be disrupted by natural and anthropogenic processes. Dams are significant disruptions to streams. Over 2,000,000 low-head dams (

One particularly complex issue confronting wildlife conservation is the role of regulated trapping as a management tool. Public opinion polls, recent ballot initiatives and referenda, and the continual introduction (and uneven success) of antitrapping legislation in state legislatures illustrate the intensity of public controversy surrounding trapping. Little is known, however, about the perspectives of wildlife and fisheries conservation professionals regarding traps and trapping. We conducted a survey to explore the attitudes and values of conservation professionals regarding a variety of conservation-related issues including whether to outlaw use of leghold traps. We sent a mailback questionnaire to a stratified random sample of 1,000 members each of The Wildlife Society, American Fisheries Society, North American Wildlife Enforcement Officers' Association, and Society for Conservation Biology. We achieved an 81% overall response rate. Respondents were divided on whether to outlaw leghold traps; 46% favored outlawing use of the leghold trap, 39% opposed outlawing its use, and 15% had no opinion. Those who favored outlawing leghold traps believed they cause unnecessary animal pain or stress, may harm nontargets, and are not a necessary management tool. The 3 most frequently mentioned reasons offered in support of not outlawing the leghold traps were efficiency of harvest, they are an important tool for managing furbearers, and that they did not adversely affect furbearer populations. Responses differed by organization membership, employer, gender, and whether or not respondents were a hunter and/or trapper. Our results suggest that conservation professionals may be as conflicted about use of the leghold trap as are public stakeholders. We believe our findings pose important questions that conservation professionals must consider if they are to provide the leadership to more effectively address wildlife management conflicts.

Land use planners have the challenge of incorporating biologically sound guidelines into development plans to balance human development with conservation of natural resources. Valued as an important component of the natural heritage of the northeastern United States, anadromous river herring (Alosa pseudoharengus, A. aestivalis) represent a model system to look at how ecological data can help conserve biological diversity in systems impacted by humans. Juvenile river herring spend 3–7 months in freshwater then migrate to the ocean. However, factors that trigger migration, and consequently influence distribution and abundance, are not well understood. Thus, our objectives in this study were to (1) describe juvenile river herring migration patterns, both “peak” (>1000 fish/wk) and “all” (>30 fish/wk) migration; (2) identify potential cues for this migration; (3) examine effects of one type of ecosystem alteration, low water levels, on river herring; and (4) suggest how this information can be incorporated into an effective conservation plan. Weekly during June–November 1994, we sampled both migrating and nonmigrating river herring and seven associated abiotic and biotic variables in one continuous and one intermittent flow system on Cape Cod, Massachusetts. We then used multiple logistic regression to predict when juvenile river herring migrate. In the continuous-flow system, juvenile river herring migration primarily occurred during the midday hours from July through early November, with the peaks of migration, comprising >96% of all migrating fish observed in early July and early September. The peaks of migration occurred during the new moon, when Bosmina spp. density was low, and all periods of migration occurred when water visibility was low, during decreased amounts of rainfall. In the intermittent-flow system, juvenile river herring migration was frequently inhibited due to low water levels, and herring were on average 25 mm smaller than those in the continuous flow system. Using these results, managers can more effectively monitor river herring populations by identifying factors associated with migration and isolating critical flow periods when fish movement is likely to occur. Thus, we can detect changes in herring population size due to human impacts. Ultimately, these data can be incorporated into an ecologically sound conservation plan for juvenile anadromous herring that may help ensure their survival while balancing human needs for natural resources.

Determining the factors that regulate recruitment of cunner Tautogolabrus adspersus, a temperate reef fish, can help assess the effect of an anthropogenic disturbance on population abun- dance. The relative abundance of cunner recruits was tracked over 1 reproductive season via visual counts on line transects across similar habitats at 4 sites across 3 boulder reefs in the vicinity of the Pilgrim Nuclear Power Station (PNPS) in Plymouth, Massachusetts, USA. Habitat characteristics including macroalgae structure, canopy height, rugosity (a measure of structure complexity), tem- perature, and visibility were measured at each site to assess the influence of these factors on recruit abundance. We assumed that immigration and emigration were not responsible for recruit abun- dance patterns through time due to the sedentary life history of cunner recruits. We observed differ- ences in recruit abundance over the settlement period among reefs which were likely the result of differences in settlement. However recruitment at the end of the post-settlement period was similar across reefs. Recruit mortality rates among reefs differed in the post-settlement period, with the reef that had the highest density also having the highest mortality rate. Post-settlement mortality rates provided evidence for density-dependent mortality, since habitat and abiotic factors failed to explain the difference in mortality among reefs. Consequently, because of the existence of density-depen- dent processes in the post-settlement stages, entrainment mortality of the pre-settlement egg and lar- val stages by the PNPS will have a diminished effect on the local cunner population. An additional assessment of within-reef variability in recruitment also suggests recruitment success is sensitive to small changes in habitat structure which can occur over the recruitment season.

Many populations of anadromous herring, (e.g., alewives Alosa pseudoharengus and blueback herring A. aestivalis, collectively referred to as river herring) are in decline. To help understand the various processes influencing their relative abundance, we studied juvenile river herring populations in 11 small, coastal Massachusetts systems. We examined diel and seasonal movements, variation in patterns of abundance, and relationships between juvenile river herring numbers and seven abiotic and biotic factors (stream discharge, pond temperature, habitat availability, pond transparency, pH, food availability, and spawning stock size). Seasonally, juvenile downstream migration peaked in early summer, and most juvenile river herring emigrated between 1200 and 1600 hours. Little or no emigration occurred in late summer when stream channels were often dewatered, although several streams experienced a smaller, more variable emigration peak in the fall. In univariate regressions, stream discharge, pond vol...

Understanding reproduction and recruitment is essential for the successful conservation of a species. An estimate of the fecundity of cunner Tautogolabrus adspersus is critical for assessing population dynamics and perturbation effects. In this study, we estimated length-, weight-, and actual age-specific fecundity relationships for cunner in Cape Cod Bay, Massachusetts. We used the gonadosomatic index to assist with selection of mature, prespawning-size fish for estimating fecundity. We then gravimetrically estimated fecundity for 205 fish 69–185 mm in total length that were collected in May and June 1994. Quadratic models on log10-transformed length and weight data each explained 71% of the variance in fecundity, and age data explained 57% of the variance. In a test of age-specific fecundity precision, three age-specific models (actual age, age back-calculated from the von Bertalanffy equation, and a calculated age estimate that was expanded to include additional data) produced consistent fecun...

Juvenile anadromous river herring (alewife Alosa pseudoharengus and blueback herring A. aestivalis) spend the first 3 to 7 months of life in headwater lakes of coastal systems. Systems that support herring often produce trophy largemouth bass Micropterus salmoides. Even though biologists, managers, and anglers have speculated about the value of anadromous herring as a key prey for resident predators, the contribution that herring make to the diets of these predators has not been assessed. Herein, we quantified largemouth bass diets in two coastal lakes, Santuit and Coonamessett ponds, that contained anadromous herring, and we used bioenergetics modeling to evaluate the importance of herring prey to largemouth bass growth. During May through November 1994, largemouth bass diets consisted of various fish species, crayfish, and other invertebrates. Although not the most important prey overall, herring were the most important fish prey consumed in both lakes based on number of individuals consumed. I...

We determined how ice affects selection of habitats and distribution of post-young-of-the-year Atlantic salmon (Salmo salar) parr during winter. Night snorkeling surveys were completed between November and April to evaluate parr habitat use and movements. Systematic measurements of water depth and velocity were recorded during ice-free and [Formula: see text]55% iced conditions to quantify habitat availability. Ice formation altered the distribution and reduced the abundance of habitats commonly used by parr; differences between parr habitat use and habitat availability were greatest when ice was present. Edge ice formation resulted in the concentration of flows, and areas of high flow were formed in midchannel; few parr were observed in midchannel after ice had formed. Through the winter, most parr were found lateral to high flows on the ice edge boundary or in the post-ice period lateral to the stream midchannel. The correspondence of parr movements during winter to changes in the physical habitat associated with ice formation indicates that movements and redistributions may be important for survival in streams affected by ice.

La predation est souvent etudiee dans des systemes aquatiques qui abritent des saumons. Etant donne que ces systemes sont difficiles a manipuler et a reproduire, il est essentiel de pratiquer des comparaisons rigoureuses entre systemes. J'examine ici la litterature concernant les facteurs qui peuvent influer sur la predation dans les systemes. J'ai evalue plus precisement si la predation sur les salmonides etait importante par rapport aux taxons proies, au stade de developpement, a l'habitat, aux donnees sur les predateurs, a la methodologie et a l'echelle spatiale. J'ai de plus recherche quels facteurs avaient de l'influence dans les systemes ou la predation etait importante. Dans neuf revues, entre 1959 et 1996, 45 etudes de terrain verifiaient explicitement l'importance des effets directs de la predation sur les salmonides anadromes proies. Les auteurs de 36 (80 %) de ces etudes concluaient a l'importance de la predation. La majorite des etudes dans lesquelles la predation etait jugee importante portaient sur les smolts soumis a la predation par des poissons dans les habitats transitionnels des cours d'eau et des estuaires. En outre, les releves a grande echelle spatiale etaient les plus couramment employes. Enfin, la plupart des etudes donnaient peu d'information sur les facteurs qui compliquent l'etude de la predation. Si nous voulons tirer une lecon de ces systemes complexes, nous devons recueillir, analyser et rapporter des types d'information similaires qui sont recoltes dans plusieurs systemes et sur plusieurs annees, a l'aide de methodes rigoureuses et systematiques.