October 19, 2015

Aquatic barriers have contributed to the decline of numerous aquatic species throughout the United States by fragmenting habitats. Although natural resource managers work diligently to reconnect habitats, they struggle to keep up with increasing water demands and infrastructure construction that lead to new barriers. This symposium featured presentations highlighting the successes and difficulties from real-world aquatic passage projects that allow for multiple uses including hydropower, irrigation, transportation, recreation, and flood management. Common themes included the keys to successful partnerships and examples of existing policy challenges and successes. Presentations also emphasized the importance of maximizing and communicating the return on investment, building trust with the community, and preventing and responding to floods. Drawing from these real-world examples, the symposium culminated in a panel discussion exploring opportunities to integrate aquatic organism needs into new and replacement infrastructure along our waterways. Discussion centered on stakeholders’ perceptions of aquatic passage projects and weaknesses in existing policies that create difficulties in working to achieve collaborative, multi-benefit solutions. The panel closed with a discussion about opportunities for new and existing aquatic passage tools and partnerships. Participants agreed to continue to collaborate on improving aquatic passage policies and programs to support healthy human and aquatic communities. — Laura Deighan, U.S. Fish and Wildlife Service, [email protected] Read the symposium abstracts here.

Our symposium consisted of 12 talks encompassing examples of transdisciplinary science from Alaska to the Caribbean and suggestions, examples, and critiques of educational opportunities for transdisciplinary training. Defining “transdisciplinary” seems of paramount interest, and while I offered a definition from Rosenfield (1992) in my introduction—individuals from multiple disciplines working jointly to create a unified conceptual framework, problem definition, and analytical approach—this definition leaves to interpretation the breadth of transdisciplinary endeavors. Our session identified the need to build new capacities to collaborate among individuals from many disciplines and to gain new technical skills to address emerging problems in marine resource sustainability (e.g., institutional analyses, management strategy evaluation, multi-criteria decision analysis). These needs underscore the importance for new educational programs that can address these opportunities; however, multiple presenters identified institutional impediments that preclude integration across disciplines. It is imperative that graduate students not surrender their disciplinary interests, as the need remains for disciplinary experts on teams of scientists. But, as many of the science talks pointed out, multifaceted problems require transdisciplinary communication, conceptual understanding, and shared methods and analytical approaches to reach tractable solutions. Rosenfield, P.L. 1992. The potential of transdisciplinary research for sustaining and extending linkages between the health and social sciences. Social Science & Medicine 35(11): 1343-57. — Kathryn Sobocinski, Oregon State University, College of Earth, Ocean, and Atmospheric Sciences, [email protected] Read the symposium abstracts here.

Sponsors: USDA Forest Service, NOAA, Trout Unlimited Despite outcry over the detrimental effects of overgrazing by livestock on riparian habitats and endangered fish, grazing remains one of the most common uses of public land in the United States and contributes to the sustainability of rural economies and landscapes. But when is grazing overgrazing? The USDA Forest Service and NOAA convened a symposium to open a dialog about this issue and explore ecological and social concerns. Nine speakers presented research findings and discussed options for providing habitat for both livestock and wildlife while protecting riparian vegetation and water quality. For example, new research shed light on the effectiveness of restoration treatments focused on salmon recovery, showing that browsing by deer and elk may prevent establishment of key native riparian hardwoods. Other studies demonstrated that managing the timing, duration, and frequency of grazing can improve conditions for trout, and that reintroduction of beaver may help increase hydraulic diversity and promote riparian vegetation growth. To date, grazing management in the face of the Endangered Species Act has been contentious and litigious. Many echoed the idea that healthy streams are a product of public/private partnerships. The final presenter, a rancher implementing restoration practices on her family ranch, summed it up: “Relationships heal rivers.” — Nathaniel Gillespie, USDA Forest Service, [email protected] Read the symposium abstracts here.

Sponsors: Australian Centre for International Agricultural Research, South East Asian Fisheries Development Centre The Mekong is one of the most unique and fascinating river systems in the world. It contains almost 1,000 fish species, which form a large proportion of the diet for almost 60 million people. The total capture fishery harvest is approximately 2 million tonnes, or 2% of the total global fisheries catch. The symposium focused on understanding knowledge gaps required to help managers deal with rapid riverine development issues currently threatening the productivity and sustainability of Lower Mekong River capture fisheries. River development will impact fisheries through connectivity, direct mortality, and habitat and flow regime changes associated with impounding. Many issues currently facing the Mekong have been dealt with by other countries for decades. Scientists from Australia, the United States, and Brazil shared experiences mitigating the impacts of hydropower and sustainable irrigation. Recent advances in technology were also explored, and innovative applications of acoustic telemetry, food-web mapping, fish physiology simulation, and GIS systems to track potential fish impacts were presented. Researchers from the Mekong shared results of ongoing fisheries research and identified important considerations for integrating current development projects into community co-management frameworks. The potential for future collaborative research was explored and an updated symposium is being planned at AFS 2017 in Tampa. — Lee Baumgartner, La Trobe University / Murray-Darling Freshwater Research Centre, [email protected] Read the symposium abstracts here.

Unlike the “real world,” simulation models provide experimental systems where the outcomes of various assumptions can be examined to help inform management decisions. Given the multiple-objective nature of fisheries management, quantitative fish population and environmental simulations have become more commonly used to help cumulate the effects of multiple management actions and environmental stressors and provide comparisons between alternative management strategies. Our symposium provided a forum for simulation models being applied in a diverse range of fisheries applications, including feedbacks between anglers and sportfish in Nebraska reservoirs, human-induced drivers of Pacific salmon populations, the effect of dam passage and delay on alosine stocks, estimating habitat needs of juvenile salmonids, environmental drivers of Longfin Smelt abundance, and an ecosystem-level approach to evaluating the health of Australian fisheries. Our symposium was capped by a presentation from Kenneth Rose, who presented an approach for best practices in selecting, implementing, interpreting, and reporting of fish modeling designed to assess the effects of restoration actions on fish populations. Rose’s presentation demonstrated that while simulation models are regularly being called upon to help inform restoration actions in a diverse array of applications, a focus on model planning and development will pay back in more effective and efficient management decisions in the long run. — Paul Bergman, Cramer Fish Sciences, [email protected] Read the symposium abstracts here.

Sponsor: Great Lakes Fishery Commission Increasing connectivity into and within rivers can benefit fishes by providing access to important habitats. Deliberate fragmentation of rivers can protect fishes by limiting the spread of invasive species. This symposium first addressed the geographic scope of interest in, and need for, selective bidirectional fish passage. It then explored the science needed to achieve it, including use of seasonal and velocity barriers, electrical guidance, and inclined ramps to selectively sort fishes. The final talk synthesized advances developed for sorting materials in the recycling industry. A facilitated discussion among ~50 attendees identified key challenges and research needs for selective fish passage. Passage and blocking success can be context-specific. The same structure may work well in one river, but not in another. Greater flexibility and fine-tuning are needed. Background information required for engineering design is often lacking, as is the will to improve success post-construction by fine tuning the design and its operation. Balancing policy objectives and passage/blocking success can be difficult. Passage and blocking devices are rarely 100% effective, but they could be less effective and still meet management targets. Sorting methods for recyclable waste could offer novel research directions to achieve the sorting of desirable fishes and blocking of invasive species required for selective fish passage. — Rob McLaughlin, University of Guelph, [email protected] Read the symposium abstracts here.

Temperature is a critical component of freshwater ecosystems, influencing a wide range of phenomena from phenology of individuals to interactions within aquatic communities. This symposium brought together empirical data, statistical tools, and mechanistic models describing thermal regimes in aquatic systems, with the intent of determining which techniques are best equipped for understanding these regimes and the role of natural and human disturbance in altering or maintaining them. Presenters exhibited the power of large collaborative datasets, customized air and water temperature monitoring programs, airborne infrared imaging, process-based hydrology/temperature models, and spatial stream network models. Each method provided a somewhat different perspective on how to overcome the challenge of high levels of spatial and temporal variance in aquatic thermal regimes in order to make predictions of future thermal regimes and identify best management strategies for thermal habitats and dependent freshwater species. Strategic data collection, analyses that incorporate covariation in water temperature patterns over space and time, and research on the impact of human disturbances like wildfire, dams, and climate change on biologically relevant aspects of thermal regimes emerged as high priorities for the future. — Elliot Koontz, UW (QERM), [email protected] Read the symposium abstracts here.

The AFS scientists tackled a diversity of effects from anthropogenic eutrophication on U.S. fish and fisheries. Although several intertwining factors were discussed in this symposium, it was clear that we are only beginning to scratch the surface of this complex issue. This well-attended symposium began with a thought-provoking keynote that explored if the northern Gulf of Mexico ecosystem should be called the “fertile fisheries crescent” as opposed to the “dead zone,” based on its sustained high productivity in spite of the hypoxic area. A major theme from this and many other presentations was that elucidating the trade-offs from eutrophication of aquatic ecosystems continues to be difficult and is not always straightforward. Researchers utilized a variety of new tools and experimental approaches to resolve these impacts, and there were several common threads related to where this discipline is headed. For instance, evaluating the impacts of hypoxia, acidification, harmful algal blooms, or other stressors has largely shifted from traditional toxicological approaches to a focus on sublethal or behavioral effects to fish using realistic exposure periods and innovative experimental designs. Overall, scientists agreed that there is an urgent need for (1) more research on these impacts and (2) better integration into ecosystem modeling. — Konstantine J. Rountos, SoMAS Stony Brook University, [email protected] Read the symposium abstracts here.

Sponsor: Cramer Fish Sciences When we first imagined this symposium, we thought we’d invite enough speakers to fill one slot. Instead, there was enough interest among AFS members to fill an entire day. We had 19 talks that all addressed fish restoration. Speakers were agency and tribal scientists, academics, consultants, and students. Some talks were focused on biological response. Some were aimed at reconnecting physical habitat within watersheds while others focused on intense in-stream habitat manipulations in river ecosystems. There were talks that explored theory, and uncertainty, and our ability to detect system responses. Results were presented from long-running watershed-wide restoration programs and comparative assessments of individual projects on small streams. The systems we learned about included highly urbanized and urbanizing Eastern Seaboard streams, Great Lakes connecting channels and tributaries, high desert beaver ecosystems, large rivers of the California Central Valley and coast, and intact watersheds of southeast Alaska. We learned about Stone Rollers and River Chubs and Lake Sturgeon and several salmonids. Nearly all of our talks addressed the needs of fish relative to the processes of their ecosystems. Emphases were on understanding and addressing system deficits in an increasingly dynamic climate, with the goal of biological conservation.   — Raymond Timm, Cramer Fish Sciences, [email protected] Read the symposium abstracts here.