Drivers and Synergies Presentations

Monday General Session

Drivers and Synergies Theme Panel Review Paper, Chair: Anthony Cox and Facilitators: Doug Beard and Abigail Lynch

Tuesday Oral Presentations

Philippine Room (Room C277, Floor 2, Building C)

Integrating Social and Ecological Paradigms to Develop a Unifying Concept for Water and Inland Fisheries Management, by Vivian M. Nguyen (Canada), Ian G. Cowx, T. Douglas Beard, William W. Taylor, & Steven J. Cooke

Human civilization around the globe has been drawn to rivers as a source of fish, irrigation, drinking water, transportation, industrial processes, and hydropower. Fluvial ecosystems are dynamic, productive systems shaped by physical, chemical, and biological processes that provide many ecosystem services. Nonetheless, inland fisheries are often managed independently of other human activities and natural processes. Rivers are inherently connected with their watershed and its human inhabitants, such that they form complex coupled social-ecological systems. It is therefore prudent to consider relevant activities (e.g., fisheries) and processes occurring in fluvial systems at a watershed-scale to ensure sustainable development and conservation of these highly valued ecosystems and the services they provide. A number of paradigms relevant to inland fisheries and watershed management are often considered independently rather than in a holistic manner. We present a holistic and transdisciplinary watershed management framework that integrates social and ecological paradigms to advance our understanding of watershed ecosystems and to facilitate transdisciplinary research and management programs. We highlight features of a watershed system that should be considered in an integrated way, such as the interaction of multiple stressors and impacts at multiple scales in understanding the response of watersheds to socio-ecological change. We aim to promote the need to shift our thinking from independent conservation units to holistic and transdisciplinary conservation that formally integrates fisheries management into a broader watershed management framework.

Triumphs and Tragedies of Partnerships: Balancing Competing Objectives for the Upper Mississippi River Restoration’s Environmental Management Program, by John H. Chick (The United States of America)

The Congress of the United States of America recognized the Upper Mississippi River System (UMRS) as a nationally significant ecosystem and nationally significant commercial navigation system in the Water Resources Development Act of 1986. This act also created the Upper Mississippi River Restoration’s Environmental Management Program (UMRR) to help managers maintain the integrity of the UMRS for multiple ecosystem services. The UMRR is implemented by the U.S. Army Corps of Engineers, in partnership with four federal agencies (U.S. Fish & Wildlife Service, U.S. Environmental Protection Agency, U.S. Geological Survey, and the National Resources Conservation Service), and the natural resource agencies of the five UMRS states (Illinois, Iowa, Minnesota, Missouri, and Wisconsin). The two main elements of the program are: (1) Habitat Restoration and Enhancement Projects to improve critical habitat of the UMRS, and (2) the Long Term Resource Monitoring Program to monitor critical UMRS resources (including fisheries) and to improve our understanding of ecosystem structure and function within the UMRS. The UMRR has a substantial record of success in both restoration and scientific research. Nevertheless, managing the multiple and sometimes competing interests of this broad partnership unavoidably creates challenges. Additionally, the UMRS is also substantially affected by anthropogenic and other influences that operate at the watershed level and are frequently beyond the regulatory/management authority of the partnering agencies. Our experience and success in maintaining a strong program and partnership for close to 30 years has relevance to the development and implementation of inland fisheries management programs in other large ecosystems.

Linking Conservation of Fisheries Resources with Livelihood Generation: Case Study from Central India, by Nilesh K. Heda (The Republic of India)

Freshwater wetlands of India are rich repositories of biodiversity and are crucial for the livelihood and survival of millions of people. Unfortunately, these vital ecosystems are facing serious threats from development activities and basin-area degradation, and they are disappearing from the landscape at an alarming rate. The cascading effects of this ecological meltdown are directly on local resource-dependent communities. The Adan and Bembla rivers of central India are the part of Godavari basin, the largest basin of southern India. For a decade, we have been working in these basins for eco-restoration and fish conservation by linking employment generation for rural people. The present paper will portray a case study of the rejuvenation of rivers and other lentic ecosystems by using a holistic ecosystem approach. Every river basin is dotted with villages where the scarcity of employment is a major issue. Using the employment guaranty act of government of India, culture of indigenous fishes, and other agriculture-based income generation avenues, we have started systematic attempts for wetland revival by involving fishermen, labor, and farmers. The systematic study of selected villages has been performed, based on the priority issues of local people, and eco-restoration activities using labor potential have started in river basin. As a short-term outcome of this initiative, people get livelihoods and as a future outcome, the condition of the local wetland resources including fishes ameliorated substantially. The attempt proved that there is serious need to link employment generation of local people, rejuvenation of local decision-making and conflict resolution systems, and conservation.

Ecological Services and Drivers of Caribbean Freshwater Fisheries, by Thomas J. Kwak (The United States of America), Augustin C. Engman, Jesse R. Fisher, & Craig G. Lilyestrom

The Caribbean region is widely recognized for marine fisheries, but island freshwater habitats support fishes that provide recreational and subsistence fishery value. Of the 82 fish species found in the freshwater habitats of Puerto Rico, United States of America, 26 are primarily freshwater species, and fewer than 10 are native. All the native fishes are diadromous and require access to freshwater river and marine habitats for existence. These freshwater fisheries span over 9,000 river km. Historically, they received relatively little attention by fisheries scientists, but that interest is expanding. Fisheries conservation and management is complex, as the native species are harvested as migrating post-larvae (ceti) and as adults in recreational and subsistence fisheries in a region with one of the highest human population densities globally. Our research over the last decade on sampling methods, ecological and management scales, basic fish biology and ecology, and ecological and human ecosystem and fishery drivers has enhanced public interest, appreciation, utility, and management potential of the stream fisheries resource, as well as facilitating a broader environmental awareness. Primary drivers that influence the fish resource include land use and stream channel alteration, occurrence and operation of dams and other stream barriers, introduction of exotic and invasive fishes and invertebrates, freshwater quality and quantity, and human interactions with the resource. Attention to each of these driving mechanisms is critical to ensure the future sustainability of these fishery resources for human services and ecological functions.

Influence of Deforestation on Fisheries in the Amazon Floodplains, by Caroline Arantes (The Federative Republic of Brazil), Kirk Winemiller, Miguel Petrere, Leandro Castello, & Carlos Freitas

The influence of forest cover on fish production in the floodplains of the Amazon basin remains undocumented despite the considerable attention garnered by recent estimates of deforestation within the Amazon. Our study aims to reveal the potential impacts of forest cover on fishery yields in floodplains of the lower Amazon River. We conducted field research during the annual flood season to assess fish populations in 126 habitats across 17 lake systems along a gradient of impacts to the floodplain (from the most degraded forest to the most pristine) in the Lower Amazon. Fishes were sampled using gillnets of varying mesh sizes in order to capture a broad range fish species and sizes normally harvested in regional fisheries. For each sampled lake system, we quantified floodplain vegetation cover using GIS. We analyzed abundance (biomass catch-per-unit effort, CPUE) patterns of fish species and trophic guilds in relation to percent forest cover of local watersheds. Positive relationships were found between CPUE and forest cover for lake systems (F = 7.27; p = 0.018; n = 17) and habitat types (F= 5.21; p = 0.024; n= 126). The median CPUE for herbivorous fishes was 1.8 times higher in pristine areas than in deforested areas. This ongoing research highlights the need to study impacts of land use, including deforestation, on fish ecology and fishery yields in the Amazon. Future analyses of fish assemblage structure, food web ecology, and local fishing activities and management will be integrated to explore relationships between ecological and social factors.

Hydraulic Fracturing and Brook Trout in the Marcellus Shale Region: A Combined Observational Study and Modeling Approach, by Maya Weltman-Fahs (The United States of America) & Todd M. Walter

Improved natural gas extraction technologies (horizontal drilling/hydraulic fracturing) have led to rapid expansion of natural gas development in the Marcellus Shale formation, which underlies 26% of the historical range for native brook trout (Salvelinus fontinalis). Activities associated with hydraulic fracturing potentially threaten brook trout populations through hydrological, physical, and chemical impact pathways. We have just completed a three-year field study in the Pennsylvania State Forest, comparing a suite of in-stream characteristics across several previously undisturbed headwater catchments, some of which have active hydraulic fracturing activity. The goal of this research is to facilitate sustainable energy development while preserving habitat quality and quantity for eastern North America’s only native stream salmonid. We examine the relationships and trade-offs between activities required to fulfill the need for supporting infrastructure, source water, and waste disposal for the hydraulic fracturing method of natural gas extraction, and the health of the adjacent aquatic ecosystem/freshwater fishery. Future scenarios related to land and water use for hydraulic fracturing are addressed through a coupled modeling strategy that links predicted drilling locations (via a spatial statistics approach based on landscape variables) to potential impacts for brook trout (via a dynamic, process-based modeling approach with parameters derived from the field study and existing literature). The model has been applied to New York State but is potentially modifiable for application in other geographic regions where hydraulic fracturing may be used, and to relevant species in those ecosystems.

Exploring the Role of Nutrients, Predator Stocking, and Climate Change on Fisheries Production in Lakes Michigan and Huron, North America, by David B. Bunnell (The United States of America), Richard P. Barbiero, Brent Lofgren, Charles P. Madenjian, & Yu-Chun Kao

Recreational and commercial fisheries in the Laurentian Great Lakes have been valued at more than $7 billion USD annually, and the United States government has invested over $1 billion USD in restoration efforts since 2010. In Lakes Michigan and Huron, nutrient inputs have undergone long-term declines since the 1970s and downscaled regional climate forecasts predict warmer water temperatures, prolonged stratification, and reduced ice cover. Owing to piscivore stocking and management of invasive sea lamprey, fisheries in Lake Michigan have remained stable while those in Lake Huron have been more variable. We present analyses of long-term food-web monitoring data and identify the relative importance of ecological drivers and key uncertainties and gaps in knowledge. Both “bottom-up” and “top-down” drivers were important, whereas the effects of climate were difficult to disentangle from other factors. Our models predicting the effects of climate change on fish production were highly sensitive to prey availability, providing further incentive for ecosystem-based fishery management.

Effects of Climate Change on Inland Water Bodies: Consequences on Livelihood and Food Security – A Case Study in Chalanbeeel, Bangladesh, by Hasan Abdullah (The People’s Republic of Bangladesh), Bangabandhu Sheikh , & Mujibur Rahman

Bangladesh is recognized worldwide as one of the countries most vulnerable to the impacts of global warming and climate change. Over the past decades, Bangladesh has been ravaged by climatic extremes like droughts, floods, heavy downpour over short spells, cyclones, and tornados. This is due to its unique geographic location, dominance of floodplains, and low elevation from the sea. Bangladesh has vast resources that support fish production. Approximately 40,000 km² of permanent and seasonal water bodies provide complex habitat for around 260 species of fish. These include seasonally inundated floodplains and rivers, small and large seasonal and permanently flooded depressions called beels and haors respectively, and oxbow lakes known as baors. The legendary Chalan beel is the largest beel (wetland) situated in the northwestern region of Bangladesh, with an area of more than 350 km² during the rainy season and about 90 km² during the dry season. Due to climate change, water and aquatic resources are now at stake. Additionally, cross-country anthropogenic activities (barrage/dams upstream) have caused a severe negative impact on the water resources and eco-systems of Bangladesh in the recent years. The rivers and channels dry up during the dry season. Using different image processing technique, ancillary data and satellite imagery, the seasonal dynamics of Chalan beel area were observed. It appears that the rainy season was delayed by two months, causing hydrological drought. Hydrological drought was interpreted using a new drought index, the Standardized Precipitation–Evapotranspiration Index (SPEI), developed by Vicente-Serrano et al. (2010). The SPEI is based on a monthly climatic water balance (i.e., precipitation minus evapotranspiration). It can be calculated for different time scales to monitor droughts. The SPEI’s main advantage over other widely used drought indices lies in its ability to identify the role of evapotranspiration and temperature variability with regard to drought assessments in the context of global warming. It influences the disruption in fish ovulation, fish feed reduction, biodiversity, etc. A socioeconomic survey was carried out to learn the changes in local livelihoods and food security. It shows that due to prolonged drought, livelihoods related to the wetland are disrupted. It also hampers the food security of the local community. Moreover, migration of both profession and place also took place due to climate change impacts on local communities. This study gives a climate change impact scenario of wetlands in Bangladesh.

The Intersection of Ecosystem Change and New Emerging Fisheries: A Case Study of Mille Lac Lake, Minnesota, by Donald L. Pereira (The United States of America), Melissa K. Treml, Richard E. Bruesewitz, Patrick J. Schmalz, Thomas S. Jones, & Paul A. Venturelli

Mille Lacs Lake is Minnesota’s premier recreational fishery, and historically one of its most productive walleye fisheries. However, this system is undergoing significant, multidimensional changes. Increased water clarity that began approximately two decades ago may be reducing lake productivity, potentially affecting walleye. At about the same time, eight North American Indian bands initiated new fisheries based on rights established in the Treaty of 1837 and upheld by the U.S. federal courts. As the tribal fisheries expanded over time, length-based regulations were implemented to limit the recreational fishery managed by the State of Minnesota to stay within its allocations of the safe total harvest estimates. Selectivity of both fisheries altered the sex, size, and age structure of the walleye population. More recent system changes include the arrival of several aquatic invasive species, notably zebra mussels and spiny water flea. The past decade has also seen increases of other native piscivores, including smallmouth bass, that may be driven by climate, and northern pike, that may be benefiting from increased water clarity and more extensive aquatic macrophytes. A key result of all these changes is a fish community that is significantly and possibly permanently different than the community that stakeholders valued historically. We will present an overview of these changes, and an initial look at potential, future fisheries management regimes. Optimal future management policy to achieve sustainability of this important fishery will depend on reducing uncertainty pertaining to causal drivers of system change.

Research Informing Management and Legislation: Merging Biology with Hydrology to Prevent Fisheries Declines in the Lower Mekong Region, by Lee J. Baumgartner (Australia), M. Mallen-Cooper, Garry Thorncraft, Douangkham Singhanouvong, Oudom Phonekhampheng, Tim Marsden, Craig T. Boys, & Chris Barlow

Rapid riverine development is threatening the productivity and long-term sustainability of Lower Mekong River capture fisheries. Over 200 new dam projects are approved every year to drive power generation and irrigation productivity. Few developments consider fisheries resources despite global recognition that infrastructure can substantially decrease productivity. Fish have a strong cultural, social, and economic value. The total capture fishery harvest is approximately 2 million tonnes, which equates to 2% of global fisheries catch. The average Lower Mekong citizen consumes 29 kg of fish per year, providing an important protein and micronutrient source. It is widely accepted that decreases in fishery productivity will adversely impact the 60 million people that rely on fish from the system. River development will impact capture fisheries by eliminating connectivity, providing a direct mortality source, and creating habitat and flow regime changes associated with impounding. Recent research has identified solutions which can help to create sustainable outcomes for Mekong fisheries. For instance, targeted laboratory trials have identified critical tolerances of fish which can influence hydro plant design. Field trials have identified design criteria for fishways that now pass thousands of Mekong fish. Much work has quantified the impact of the regulation of fish populations and potential livelihood impacts. There is now sufficient data available to incorporate fish-friendly attributes into infrastructure developments. Effective legislation and enforcement, implemented through local management strategies, is necessary if fisheries resources are to be maintained. Implementing these changes is critical to protect important capture fisheries, and maintain livelihoods, into the future.

Lunch break

A Dam by a Thousand Canals, by Sui Chian Phang (Malaysia), Sarah Laborde, Ian Hamilton, Mark Durand, Bryan Mark, Ningchuan Xiao, Roland Ziebe, Mahmaat Aboukar, & Mark Moritz

The global erosion of freshwater system health to sustain numerous, multi-sector services is a major threat to the biological diversity and productivity inland fisheries are reliant on. Sustainable freshwater management is dependent on identifying and synergising the demands of the different sectors. In the Waza-Logone floodplain in northern Cameroon, a reflooding scheme has seen the recovery of habitat, fish, and fishing from the devastating impacts arising from the construction of the Maga Dam. However, an alternative threat to habitat and fisher livelihood that may equal the impact of the dam has emerged from within the fishery sector itself. Fish canals work by draining floodwater back into the river and fish are caught in nets affixed within them. With canal length measurable in the kilometres and numbers currently in their thousands and still continuing to grow, the cumulative movement of water through them impacting on flooding patterns is significant. Here, we present the results of a 2014 survey of canal production and the socioeconomics of fishermen in the region; identify the impacts on the social, ecological, and hydrological systems; and examine the drivers behind the increase in canal construction. Futures scenarios are described but this is the first step in pursuing a sustainable fishery sector in a region where current management systems are inadequate and recent population growth and foreign unrest threatens to destabalise the region. The challenges facing the integration of canal and non-canal fisheries for sustainable freshwater management are the same as those between fishery and non-fishery freshwater sectors.

Dams: A Ubiquitous Landscape Feature Affecting Fisheries, by Daniel B. Hayes (The United States of America)

Dams have a profound influence on the structure and function of rivers worldwide, and greatly alter the productivity of inland fisheries. Changes in the biological status of freshwater fisheries driven by dams vary, sometimes increasing total production, but often leading to reduced production. A complexity introduced is that the location of production can be shifted relative to pre-dam conditions, leading to conflicts among stakeholders. The telegraphing of effects of dams both upstream and downstream has important implications for policies and governance initiatives related to dams, as does the multitude of human economic and social considerations that dams touch. Regulating the construction of new dams, operation of existing dams, and decommissioning of defunct dams will require a variety of strategies in order for sustainable fisheries to be achieved.

Impacts of Upstream Dams and Irrigation on the Fishes of the World’s Largest Desert Lake, by Natasha Gownaris (The United States of America), E. Pikitch,  W. Ojwang,  R. Michener  & L. Kaufman

Lake Turkana, Kenya, is the world’s largest desert lake and is fed primarily by Ethiopia’s Omo River. Dam and irrigation development will alter the Omo River’s flow patterns over the coming decade, with a possibility of virtually terminating freshwater inflow, dropping lake level, and dampening intra-annual fluctuations. Tribes inhabiting the region depend increasingly upon fishing due to the unsustainable nature of their traditional livelihood of pastoralism. Despite the importance of the lake’s fishes to wildlife and tribes, the ecosystem is remarkably understudied. Water management in the Omo basin will trigger two phases of profound impact to the Lake Turkana fish community. Initially, species dependent upon littoral habitats and flood pulse breeding cues will suffer, with knock-on impacts to the lake food web as a whole. Species resilient to these changes will face drastic increases in salinity and alkalinity as the lake dries up. We employ stable isotopes and hydrological modeling to makes inferences regarding the winners and losers of the ecosystem following the first phase of change. Our stable isotope results suggest that many of the lake’s pelagic fishes are specialist feeders. Among the lake’s tilapia species, which act as important conduits of energy in littoral habitats, there are both generalist and specialist feeders. Hydrological modeling suggests that the lake’s most extensive macrophyte beds and productive fisheries areas, respectively, will be among the first habitats lost as the lake recedes. Based on our results, we predict that Lates niloticus, Oreochromis niloticus, and Synodontis schall will be among the winners and that A. baremose, H. forskalli, L. horie, and T. zillii will be among the losers in the highly altered Lake Turkana ecosystem.

Improving the Design of Irrigation Infrastructure to Increase Fisheries Production in Floodplain Wetlands of the Lower Mekong Basin: Lao PDR, by Oudom Phonekhampeng (The Lao People’s Democratic Republic), Lee J. Baumgartner, Z. Daniel Deng, Garry Thorncraft, Craig A. Boys, Richard S. Brown, Kate B. Martin, Anna Navarro, Brett Pflugrath, & Douangkham Singhanouvong

Irrigation infrastructure can be used to regulate floodplain river flows, protecting crops from river flooding during wet seasons and retaining water during dry seasons. Regulators also have the capacity to generate electricity if coupled with mini-hydropower facilities. But infrastructure needs to be managed to protect the fishery by ensuring safe fish passage is provided. Structures known as fish ladders help fish move upstream past weirs and dams, and the practice of building or upgrading these ladders is well established. But, far less has been done to restore downstream migrations. Fish have a high likelihood of encountering some type of river infrastructure during their downstream movements. So, it is important to design these structures in a way to help fish safely gain passage. Positive outcomes of bi-directional fish passage include farming communities and management authorities having increased awareness of fish welfare issues, adopting use of fish-friendly structures, and understanding the economic, social, and environmental benefits of restoring a holistic approach to fish passage.

The Virome Associated with Ballast Waters in the Great Lakes, by Joan B. Rose (The United States of America), Tiong G. Aw, & Yiseul Kim

The global shipping industry exchanges 3 to 5 billion tons of water every year. Uptake of water on such a large scale can transport marine animals, viruses, bacteria, and other biological organisms across the globe. The introduction of microorganisms through ballast water is a growing concern and may contribute to invasive species. However, the microbial diversity of ballast water remains largely a “black box” and potential ecosystem impacts and public health risk are not well understood. Viruses are small infectious agents that exist through parasitic relationships with their wide range of hosts including animals, plants, and bacteria. Examples of viruses that have been identified as invasive species introduced in ballast water are the fish pathogen Viral Hemorrhagic Septicemia and marine cyanophage in the Great Lakes, and Infectious Salmon Anemia Virus (ISAV) in Europe and Chile. In order to gain a better understanding of the potential for viral invasions, we characterized viral communities in ballast water from different geographical sources using high-throughput metagenomic sequencing. Metagenomic analysis of ballast water samples from the Port of Duluth-Superior revealed a viral community that was dominated by viruses that infect bacteria called bacteriophages (mainly myo, podo- and siphoviruses) and algal viruses. Understanding these passengers in ballast water will assist in developing viral controls for ballast water treatment.

Fostering Socioeconomic and Environmental Benefits via Freshwater Ornamental Fisheries, by Scott Dowd (The United States of America) & Rajeev Raghavan 

For decades, the global trade in freshwater fishes for home aquariums has provided livelihoods for rural people, often serving as the economic base in regions of critical biological importance. These fisheries generally consist of low biological off-take, especially when considering the revenue generated for fishing communities and others. In addition, there is evidence that these fisheries drive environmental protectionism and therefore help maintain many more vital ecosystem services. However, the social and environmental benefits from these fisheries are threatened by many external factors. For example, animal rights organizations and other NGOs are actively encouraging ex-situ captive breeding. This effort is threatening the intact ecosystems that the fisheries rely on, the biodiversity intended for protection, as well as the livelihoods supported by these fisheries. The IUCN Freshwater Fishes Specialist Group recently established a sub-group with the objective to better identify and catalogue case studies of fisheries which result in socioeconomic and environmental benefits. Public aquaria and zoos have demonstrated interest in helping to foster environmental outcomes by showcasing such fisheries to their millions of visitors and providing guidance to those interested in the hobby so that they, too, make sound decisions. The commercial trade itself must improve public perception and connect with customers that also increasingly value the environment. By applying the findings of IUCN and partnering freshwater specialists, and working with zoos and aquariums to educate the public, it may be possible to enhance social and environmental benefits and ecosystem services through wild capture fisheries for the home aquarium trade.

Economic Valuation of Water Quality Hazards on Rice-Prawn Farming and its Impact on the Livelihoods of Fishing Communities along Vemband Lake, by Joy Rosewine (The Republic of India) & K. Thomson

Inland water fisheries offer a variety of direct and indirect economic benefits and socio-cultural values to local communities. Apart from supplying food, inland fisheries act as an informal regulator of water quality and assure the delivery of ecological services essential to sustain food production systems like aquaculture, although these values have never been officially estimated and used in policy. Unfortunately, operations of modern industries located on the banks of inland water bodies have increased the pollution levels and degraded the quality of water and food production systems. This paper examines the growth of water quality hazards in aquaculture farms around Vembanad Lake by considering seven water quality variables like temperature, salinity, pH, DO, ammonia, nitrate, and phosphate in an attempt to understand the spatial variation and impact of water quality in rice-shrimp farms along Vembanad Lake. Further, we evaluate the hazard matrix by assessing the spread of diseases, mortality, retarded growth, and production loss. We further noticed that the loss in water quality and the expected loss to crop/food production has reduced the lease values of wetland properties along the water body. The paper tries to evaluate how far the lease prices of the farms are impacted by these water quality hazards. This is studied through contingent valuation method/hedonic pricing. The study highlights the need for integrated management of resources to ensure resource health and food security.

Landscape Scale Dynamics of Fishers, Fish, and Policy: Experiments, Data, and Models of Canadian Recreational Fisheries, by John R. Post (Canada), A. Clarke, W. Haider, T. Carruthers, M. McAllister, & K. Dabrowska

Recreational fisheries in lake districts are social-ecological systems with dynamic interactions across spatial and temporal scales. Diversity of angler behaviours, variability in fish production, and constraints on management policy create a complexity of outcomes that are difficult to understand and manage. Despite the high economic and social value of many of these fisheries, resources are usually inadequate to develop best management practices on a site-by-site basis. One approach to management of such data poor fisheries is to conduct adaptive experimental management (AEM) regimes with the twin goals of optimizing policy and improving our understanding of these complex social-ecological systems. We are conducting an AEM on a large, high value recreational fishery in British Columbia involving a combination of stocked and wild rainbow trout fisheries. A series of whole lake experiments are being conducted, manipulating stocking rates and management policy across clines of ecological productivity and angler effort. In concert with the experiments, we are assessing angler behaviour, fish population dynamics, and resultant spatial and temporal patterns in fishing quality. Spatial models, conditioned to field data, are being used to determine optimal management policy in support of a series of explicit objectives for this fishery.

Inland Fisheries and Global Food Security:  Can We Gather Insight from Land-based Agricultural Systems? by Steven G. Pueppke (The United States of America)

Inland fisheries are among the most underappreciated contributors to food security in developing countries. Fish harvest usually occurs at small scale, often just for local consumption. If markets do exist, they are primitive and fragmented, and fishermen lack access to market intelligence. Data are scarce and unreliable, too, and so fisheries are rarely high on the agendas of funders and others committed to reducing poverty and enhancing food production in food-insecure regions of the world. With an eye toward the rapid proliferation of new technologies, land-oriented agricultural experts are devoting increasing attention to redesign of traditional crop-based value chains. There is new emphasis on entrepreneurial and management skills, unconventional sources of talent, and achievement of 3P value: people, planet, and profit. Experimentation is also underway with concepts such as Living Labs, which promote real world innovation and learning that is focused on users. Rapid population growth in urban areas is being viewed not just as a challenge, but also as an opportunity for agriculture to deliver more services to the city than just food. By attracting the attention of businesses, urbanization also presents an opportunity to collaborate with firms to create shared value. These are powerful drivers with the potential to create equally powerful synergies and learning across food systems, including those reliant on fish.

Poster Presentations

Posters are on display in the FAO library (ground flo0r) during all three days of the conference. Poster authors will be present with their posters during the poster session reception on Tuesday at 17:00.

Dams and Riverine Fisheries in India: A Need for New Approaches, by Parineeta Dandekar (The Republic of India) & Himanshu Thakkar

Although India is the second largest producer of inland fish globally, the proportion of riverine capture fisheries is barely 10% and declining. This is worrying, as riverine fisheries provide livelihood and nutritional security to over 15 million Indian fisherfolk. Riverine fisheries are collapsing, severely affecting fish diversity and livelihoods. Main drivers accelerating this collapse are India’s 5,000+ dams and hydropower projects, many of which are affecting rich freshwater fisheries zones. Several species like Tenualosa ilisha, carps, eels, Tor sp., freshwater prawns, etc., have been affected by competing demands from irrigation, water supply, and increasingly hydropower. This has been a blow to riverine fisher communities, one of the most vulnerable sections of Indian society. They do not receive compensation or rehabilitation benefits when dams are built and are not recognized as legitimate water users, nor considered when decisions regarding dams or environmental flows are made. This has resulted in increasing strife and societal conflicts. There is significant scope for improving dam siting, construction, operations, and management to help riverine fisheries and dependent communities in the future. The paper at hand documents the impacts of dams on riverine fish and fisheries with specific examples, data, interviews, and success stories. The paper also puts forth institutional and policy recommendations to help rivers, riverine fish, and fisherfolk in India and South Asia. It explores the synergy of riverine fisheries with emerging fields like river restoration and rejuvenation.

Impacts of Exotic Fish Species on Natural Environment in Viet Nam: A Review, by Vu Vi An (The Socialist Republic of Viet Nam)

Fish and other aquatic animals are often introduced for aquaculture species diversification and for entertainment as pets in the world. Viet Nam is one country that introduces most species into the territory for different purposes. Recently, some temperate high-value species like sturgeons and rainbow trout were introduced into the highland cold waters of Viet Nam for aquaculture. The introduction certainly has positive impacts in some extent, such as food supply and improved income for rural people. However, negative impacts have been reported at different risk levels due to habitat alteration, feed competition, and predation of indigenous species. There are at least 54 inland exotic fish and other aquatic animals in Viet Nam. A risk assessment model was used to assess the level of organism risk potential and pathway risk potential. The model is divided into two major components, the probability of establishment and the consequence of establishment for assessment, and it finally classifies into three risk levels as “Low” (acceptable organism with little concern), “Medium” (unacceptable organism with moderate concern), and “High” (unacceptable organism with major concern). The results show that 29.63% of the species are classified as low risk, 48.15% as medium risk, and 22.22% as high risk. Impacts on habitat alteration, feed competition, and predation, leading to loss of diversity of endemic wild fish stocks are discussed in the report. Finally, existing policies or regulations for alien species are also reviewed and recommended to improve management measures.

Assessing Fish Population Vulnerability to Types of Parasite Impact to Safeguard Fishery Production, by Sui Chian Phang (Malaysia), Rob Britton, Richard Stillman, Dylan Roberts, & Rudy Gozlan

A proactive management approach to the threat that non-native parasites pose to all inland fisheries is important, as impacts on host populations can be extremely severe and can be costly and impractical to reverse. Robust predictions of potential impact prior to introduction are a current bottleneck as resources are shared across a diverse pool of potential parasites created by increasing global connectivity. However, traditional approaches are parasite-centric, reflected in parasite-specific studies, when the crux of management concern is on host population responses. Here, we demonstrate that by shifting focus to investigating fish-host vulnerability to specific types of parasite impacts, an assessment of population sensitivity to different parasites is made and can help the allocation of resources to parasites that most threaten fisheries. First, we identified physical, bioenergetic, and behavioural impacts that infections have on salmonids and define them in how host physiology and behaviour are correspondingly affected. These impacts are then modelled independently in a previously validated salmonid individual-based model (IBM) to predict the respective growth rates of infected and healthy subpopulations. This modelling technique is appropriate as it predicts population responses at the scale at which management is concerned about by modelling interactions at the scale of the individual, where host-parasite interaction occurs. Results identify the type of host-parasite impact in salmonids that elicit the greatest effect on growth rates at the population level. This approach can be applied to other species and simulations can test how population sensitivity changes across different environments, demonstrating a both theoretical and applied use.

Capture Fishery in Relation to Nile Tilapia (Oreochromis niloticus) Management in the Mountainous Lakes of Pokhara Valley, Nepal, by Md Akbal Husen (The Federal Democratic Republic of Nepal), Subodh Sharma, Jay Dev Bista, Surendra Prasad, & Agni Nepal

Nepal is rich in water resources, and fishing is a longstanding tradition. Capture fisheries are an important sector of fisheries in Nepal and contribute approximately 0.5% to national GDP. The fish catch data of Phewa, Begnas, and Rupa lakes of Pokhara valley from the year 2006-2011 were analyzed to know the trends of exotic fish such as Nile tilapia and native fish. There was an increasing trend of Nile tilapia and decreasing trends of native fish species catches in total fish catches from lakes of Pokhara valley. Nile tilapia has now established in these lakes. The fish productions from capture fishery have been increased in these lakes. Due to the increase in Nile tilapia catches, the income of Jalari community has increased and enhances their livelihood. However, no doubt that the native fishes of Pokhara valley lakes are high valued and also it provides direct livelihood to Jalari community living around the lakes. Regular monitoring and stock enhancement programs of native fish species and also selective harvesting of Nile tilapia will mitigate the problem. To control further expansion of this species into other natural lakes, reservoirs, and rivers of this country, native fish conservation policy, laws, and protocols should be rigorously enforced in the country. This paper discuss with the increasing trends of Nile tilapia (Oreochromis niloticus) in total fish catches and their possible affect on native fish species and livelihood of dependent community of three lakes (Phewa,Begnas, and Rupa)of Pokhara Valley.

The Success of Ecological Criteria-Based Biological Assessment in Turkey’s Inland Waters, by Sedat Vahdet Yerli (The Republic of Turkey), Fatih Mangit, & Mustafa Korkmaz

One of the tools is the ecological quality criteria to determine the actual biological assessment of aquatic ecosystems. Many of the aquatic ecosystems in Turkey have multiple uses including fisheries. Turkey has been working on implementing the Water Framework Directive (WFD) for the determination of ecological quality and management of its inland waters. The compositions of fish species and its abundances are one of the parameters to understand the biological status of inland within WFD.  Several basins had been classified according to their ecological status in recent years in Turkey. A case study for the freshwater resource from selected basins is classified according to WFD criteria and results are compared with the other directives (such as Water Pollution Control Directive) used in Turkey as well as some trophic state determination indices. In addition to this comparison, the ability of these indices to reflect biological parameters was assessed. This presentation reports to determine the accuracy and effectiveness of biological assessment as well as presenting some of the results and challenges from ecological state determination studies conducted in Turkey with possible solutions. Briefly, the technical application of WFD has some difficulties in Turkey due to huge ecosystem diversity.

A Review of the Biological Impact of Cichlid Fishes in Aquatic Ecosystems in Nigeria, by Afamdi Anene (The Federal Republic of Nigeria)

Cichlids are known to have originated from Africa and Madagascar. They have been transplanted to South and Central America, India, Sri Lanka, Jordan, Thailand, Haiti, Australia, United States of America, and probably Russia. In Nigeria, cichlid fishes are known to inhabit a wide range of aquatic habitats based on their ability to withstand various environmental conditions. They inhabit rapids, permanent and temporary pools, deep and shallow lakes, rivers, lagoons, and brackish waters. Cichlids are known to have a broad spectrum of feeding habits that can be described as omnivorous and euryphagic with some degree of plasticity. Breeding amongst cichlids is varied and include biparental substrate brooders (Tilapia), paternal and biparental mouth brooders (Sarotherodon), and maternal mouth brooders (Orechromis). Cichlids serve a multiplicity of purposes which includes economic and nutritional value to fishers and members of littoral communities. Although this family of fishes is widely spread in Nigeria, information on its aquaculture potential is minimal. In Nigeria the contributions of members of this family of fish to inland fish production, especially fish culture, is undermined by many factors that include stunting and prolific egg production potential. This paper reviews literature on the biology of cichlid fishes with a view to assessing the impact of members of this family on aquatic systems in Nigeria and its contribution to fish production. In the face of emerging new technologies like genetic engineering, members of this family can be harnessed to bridge the gap between fish consumption and production in Nigeria.

Innovative Initiative for Enhancing Inland Fish Production Utilizing Granite Quarries: A Case Study from South India, by P. A. Vikas (The Republic of India) & Sinoj Subramannian

Inland fish resources are undergoing depletion day by day due to anthropogenic interventions such as sand mining, hydroelectric projects, unscientific sewage disposal, destructive fishing practices, etc., and also due to the impacts of climate change such as salinization, floods, etc. Promotion of aquaculture using hatchery-produced seed is the only viable alternative for reducing the fishing pressure on indigenous species and also for addressing the ever increasing demand for fish protein for human nutritional security. Suitability and sufficiency of area are the main constraints for promoting fish culture in inland areas. More than 6,000 granite quarries exist in the foothills of Western Ghats, the longest mountain range of southern India. These perennial freshwater reservoirs are optimum for initiating fish culture, whereas normal farming methods are not viable due to the depth ranging from 10 to 60 m. With a view to utilize these resources, a cage fish culture model was developed and demonstrated in partnership with a traditional farmer. Small floating cages made using HDPE nets and PVC pipes were erected in the quarry. Locally preferred fish species pearl spot, tilapia, and Pangasius were cultured in cages. Average production from one cage was 130 to 150 kg and the farmer received a net income of INR 14,300/-. One cent area can accommodate 7 such cages. The demonstration realized the practical viability of the model. This model can be widely adopted in granite quarries for enhancing fish production for livelihood and nutritional security in the region. 

Increased Eutrophication and Resulting Microcystein Concentrations in the Nyanza Gulf, Lake Victoria, Kenya, by Lewis M. Sitoki (The Republic of Kenya), Chrispine S. Nyamweya, & James M. Njiru

Nyanza Gulf is a large shallow bay of Lake Victoria suffering from eutrophication from human activities. An investigation of the harmful algal blooms as a consequence of eutrophication, both in space and time, was conducted by evaluation of environmental conditions, phytoplankton community composition, and microcystin (MC) concentrations from the inshore areas of Kisumu Bay along a transect to the open lake, between July 2008 and September 2009. The sites located in Kisumu Bay and the central gulf were most strongly affected by eutrophication, including increased nutrient concentrations and phytoplankton growth. More than 90% of the samples obtained from the gulf were dominated by cyanobacteria, whereas diatoms only dominated in the samples obtained from Rusinga Channel and the main lake. In general, Microcystis accounted for the largest part (50-90%) of cyanobacterial biovolume. MCs were found in 35 (54%) out of 65 samples and were detected throughout the study period in the gulf, but only in two out of eight samples from the main lake. A significant linear relationship between Microcystis biovolume and MC concentration was observed (n = 65, R2 = 0.88, P>.001). The highest MC concentrations were recorded in Kisumu Bay between November and March (max. 81 µg/L) when Microcystis showed max. biovolume (18 mm³/L in November 2008). The results suggest that seasonal variability did not outweigh the spatial differences in phytoplankton composition and MC production, which is seasonally persistent in Kisumu Bay.

Does the Tank Cleaner (Pterygoplichthys spp.) Clean Out Fishermen’s Livelihoods? The Case of Huruluwewa Tank in Anuradhapura, Sri Lanka, by G. G. N. Rathnayake, R.H.G.R. Wathsala (The Democratic Socialist Republic of Sri Lanka), A. P. S. Fernando, T. V. Sundarabarathy, & D. S. B. Dissanayake

The rapid amplification in tank cleaner populations have disrupted the freshwater bodies in Sri Lanka. According to the records, Huruluwewa tank is one of the inland water bodies heavily infested by tank cleaners. Their impact on fishing is not yet fully revealed. A questionnaire survey was conducted to examine the impact of tank cleaner on fishing using a sample of 60 fishermen from the tank. Pearson correlation analysis was used to analyze the data. Significant correlations (P<0.05) existed between fish revenue (negative), cost of fishing (positive), and total food fish catch with tank cleaners. The results revealed tank cleaners have increased the cost of fishing by increasing the effort of fishing while decreasing fishing revenue. The cost of fishing was increased as a result of heavy damage to nets and an increase in fishing time due to the elevation of the tank cleaner population. More than 76% of fisherman claimed that the damage to nets is severe after the tank cleaner invasion and presently the nets last for about six months, which was used to last for more than a year before. This has increased both repair time and cost of replacing nets. All fishermen stated that the high yield of tank cleaner has reduced the food fish catch, resulting them engaged with more effort and time to gain a sufficient catch of food fish to secure their daily earning as before while increasing the opportunity of fishing. These results conclude the tank cleaner has become a potential threat to the livelihoods of fishermen.

Rapfish for Reservoir Fisheries Management in Indian States, by Chrispin C. Lloyd (The Republic of India) & P. S. Ananthan

Reservoirs, the “man-made lakes” covering more than 1% of India’s land surface are created primarily for irrigation, power generation, and other water resource development purposes. Hence, development of reservoir fisheries has gained its momentum only in recent years. Fisheries management and policy-makers are grappling all over the world with the problem of how fisheries can be made to operate sustainably. However, there are only two existing methods to assess the management of reservoir fisheries: conventional stock assessment and the Ecopath model. In fact, both of the above mentioned models have focused only on certain biological/ecological aspects in reservoir management and completely neglect the importance of human dimensions in reservoir fisheries management. Whereas several social studies made in the recent past have captured and documented the importance and major role of institutional arrangements, governance, and the socio-economic and cultural profile of resource users (fishers) in effective reservoir fisheries management. Thus, it is to be noted that none of the studies have attempted a holistic understanding of the complex nature of reservoir fisheries management by giving equal importance to biological/ecological aspects as well as socio-economic/institutional aspects. Hence, the study will adapt and improvise/refine the RAPFISH (Rapid Appraisal for Fisheries) methodology, developed primarily for study of marine fisheries sustainability, as an effective tool to aid the reservoir fisheries management. RAPFISH is a rapid appraisal technique, designed to allow an objective, transparent, multidisciplinary evaluation, but it is not intended to replace conventional stock assessment for setting quotas. The standard version of RAPFISH now evaluates fisheries sustainability in six evaluation fields: ecological, technological, economic, social, institutional, and ethical. Fish populations, ecosystems, and fishing gear are captured in the first two evaluation fields, while the other four fields constitute the human dimensions of fisheries. This study would help provide a quantified benchmark about the present status of reservoir management in Indian states based on multiple parameters covering both biological and socio-economic and management parameters. This assessment in turn would help states and centre in planning more appropriate and effective management measures to sustain and develop reservoir fisheries and livelihoods.

Adaptation Strategies of Fishermen and Tropical Small Scale Fisheries to Environmental Variability: What to Expect from Anthropogenic Changes, by Victoria Judith Isaac (The Federative Republic of Brazil) & L. Castello

Water ecosystems of the Amazon basin represent a hydrological complex forming a singular landscape that strongly alternates with rainy seasons and dry periods. This study tests the hypothesis that the local fishermen carry out their activities efficiently, adapting to the seasonal dynamics of the ecosystem and to the ecology and behavior of the biota. For this we analyzed an unparalleled time series of 12 years of catches by artisanal gillnet fisheries landed in the city of Santarem in the Lower Amazon. The CPUEs of the main caught species were ordered with a principal component ordination and correlations with the space-temporal dynamic were surveyed, seeking to define the seasonal and inter-annual patterns. The results indicate that the fisheries are clearly divided according to the intensity of rainfall. Dry season fishing occurs in the river channel and focuses on large migratory catfish; during the rainy season, fishing is concentrated in lakes and flooded areas of floodplain on smaller species. The main species have different life cycles and alternate in the use of environmental resources available for feeding, spawning, and growth rates. Among years, changes in productivity are related to the intensity and duration of floods or droughts. It is concluded that despite the lack of technology, the fishermen of the region optimize their efforts, adapting their choices according to the environmental dynamics and biota of the Amazon to maximize their income. Global climate changes and large hydropower construction can affect this delicate adjustment, endangering the food security of these riverine communities.

Forgotten Fisheries: Putting Freshwater Recreational Fisheries on the Political Agenda Around the Globe, by Steven J. Cooke (Canada), Robert Arlinghaus, Brett Johnson, Shannon Bower, T. Douglas Beard, & Ian Cowx

In many industrialized countries, recreational fisheries are the most economically important form of inland capture fisheries. In emerging and developing countries, recreational fisheries are growing in popularity but not without concerns regarding the social and ecological consequences of these activities. Unfortunately, there is little information specific to the needs of communities in these regions to guide the sector’s growth. Moreover, in the industrialized world, recreational fisheries are regularly overlooked or even forgotten by policy makers and the public – after all, it is just about fishing for fun, isn’t it? However, recreational fisheries generate substantial personal and socio-economic benefits. Also, the recreational fishing community represents an engaged group of stakeholders who contribute to conservation efforts that benefit freshwater ecosystems. Here we will discuss what we term the “forgotten fisheries” – the recreational fishing sector. That recreational fisheries statistics are rarely collected or reported is telling in an era of concern for the sustainability of aquatic resources. In 2012, the UN FAO developed the first set of technical guidelines for recreational fisheries that provide a template for sustainable development of the recreational fishing sector, but these guidelines need to be applied at management scales. We identify where there is potential for conflict among fishing sectors in inland waters and how recreational fisheries could be involved in improving livelihoods and nutritional security. It is time to include freshwater recreational fisheries on the political agenda as they represent an important stakeholder group that should not be forgotten.

Thermal Tolerance of Tropical Freshwater Fishes: Predicting the Effect of Climate Change on Equatorial Waters, by Elizabeth A. Nyboer (Canada) & Lauren J. Chapman

The unprecedented rate of contemporary climate warming is affecting inland aquatic ecosystems across the globe. Major ecological changes can exert strong selection pressure on freshwater species, including those that make up important inland fisheries. A key trait that can determine how fish cope with rising heat stress is their thermal window. Thermal niche theory predicts that species adapted to a wider range of temperatures (temperate species) will fare better under global warming than those with narrow thermal windows (i.e., tropical species); however this has rarely been tested, and studies based in temperate systems far outnumber those focusing on equatorial waters. Determining the acclimation potential of organisms is key to making predictions about how populations will respond to global warming. In this paper, I provide an overview of current knowledge on thermal tolerance of tropical species, focusing specifically on predictions relating to the aerobic scope and thermal tolerance of the Nile perch (Lates niloticus), a large-bodied and heavily exploited species in the Lake Victoria basin of East Africa.

Hybridization in Fishes: Unimportant Rarity or a Threat to Biodiversity? by John Epifanio (The United States of America)

Carl Hubbs first confronted the idea 60 years ago that interspecific hybrids among freshwater fishes were more than an idle curiosity. In part because of the way we defined “species” under the Biological Species Concept, hybridization has been viewed to be unimportant as a common process or as a direct threat to biodiversity in freshwater ecosystems. A rich scientific literature has emerged over the past few decades that not only reports on the occurrence of hybridization, but also has matured in addressing some of the causes and consequences. In this presentation, I will identify some examples of where and why interspecific hybridization occurs among North American fishes. I will also present some of biases widely associated with management perspectives on hybrids that emerge from the differing societal values of fishes (e.g., food, recreation, biodiversity). Last, I will discuss some of the fishery resource management and policy difficulties that emerge because hybrids do not fit neatly into a species-based management regime.

Fishery Implications of Diverging Life History Characteristics Between Naturalized and Stocked Chinook Salmon in Lake Michigan, USA, by Mark W. Rogers (The United States of America) & David B. Bunnell

Naturalization of stocked populations can result in divergence of life-history traits from domestic stocks.  Lake Michigan supports popular Chinook Salmon (Oncorhynchus tshawytscha) fisheries that have been sustained by stocking since the late 1960s.  Natural recruitment of Chinook Salmon in Lake Michigan has increased in the last few decades and currently contributes over 50% of Chinook Salmon recruits.  Samples collected as part of a lakewide mass-marking of Lake Michigan Chinook Salmon, starting with the 2006 year class, indicated hatchery fish average 30-mm longer and 130 grams heavier than naturalized fish at age-1.  We hypothesized that selective forces differ for naturalized and hatchery populations resulting in divergent life-history characteristics with implications for Chinook Salmon population production and the Lake Michigan fishery.  We combined a historical data analysis with a field project to identify trends and origin specific traits. Specific life-history metrics of interest included: age and size at maturity, spawning run timing, fecundity, sex ratio, and egg thiamine concentrations.  We found weak evidence of divergence in life-history demographics and that environmental effects may be more influential than population-specific characteristics.

Persistence of an African Inland Fishery in the Face of Climate Change: Aerobic Performance and Upper Thermal Tolerance of Nile Perch (Lates niloticus), by Emmanuelle Chretien (Canada) & Lauren J. Chapman

Assuming organisms are adapted to the thermal regime of their environment, their temperature limits and thermal optimum should fall with the temperature range of their natural habitat. The effect of water temperature on aerobic performance of fishes is key to determining persistence of populations faced with rising water temperatures, and oxygen- and capacity-limitation of thermal tolerance (OCLTT) is an important conceptual framework for predicting their response to thermal stress. However, there is critical need for empirical studies to evaluate the generality of this hypothesis, particularly for tropical fishes, many of which contribute to food security. In Africa alone, about half of the human population relies on fish for more than 20% of its animal protein intake. Africa’s largest inland fishery is fueled by the large piscivorous Nile perch (Lates niloticus). In this study, we conducted respirometry and critical thermal maximum (CTmax) trials to evaluate the effects of body size and habitat conditions on thermal tolerance of Nile perch. Juvenile perches (5-20 cm TL) from two distinct habitats (forest edge and wetland ecotone) of Lake Nabugabo (Uganda) were acclimated for a minimum of three days to ambient conditions (25.5° C) and elevated water temperatures (27.5° C, 29.5° C, 31.5° C) prior to these experiments. CTmax was 38.6±0.8 °C (mean±s.d.) and did not vary with fish total length. As predicted, CTmax increased with temperature acclimation (P<0.001); however, the rate of increase was higher for wetland ecotone Nile perch (P=0.04).