Management Of Lake Fisheries Research Articles

Biomass and sustainable yields of Eurasian perch (Perca fluviatilis) in small boreal lakes with respect to lake properties and water quality

Understanding of factors that explain variation in potential fisheries yields is essential for the ecosystem-based management of lake fisheries. We used mark-recapture and Nordic survey net sampling to obtain estimates of Eurasian perch (Perca fluviatilis) abundance in 28 small (13.3 ha ± 11.4 ha, mean ± S.D.) boreal lakes. A size-structured population model was calibrated for each lake using further individual data to derive estimates of potential yields. Principal component scores formed from physical and chemical environmental parameters and a simple score reflecting the relative photic area of the lakes were then used to explain variation in theoretical yields to identify potential environmental proxies for fisheries management purposes. The estimated mean biomass of perch in the study lakes was 52.4 ± 51.2 kg ha−1, and the maximum sustainable yield, obtained with environment-dependent recruitment size was estimated to be 9.4 ± 12.1 kg ha−1 yr−1. The estimated yields were highest in shallow lakes with good oxygen saturation and with high percentage of euphotic bottom while excess nutrients decreased yields and alkalinity was marginally predictive for catch of large individuals. Our study provides quantitative estimates of potential yields of varyingly sized perch and helps to develop environmentally informed management for small lakes of which some are surprisingly productive.

Analyses of Protection and Conservation According to the Fish Act 1950 in Bangladesh’s Kaptai Lake Fisheries Management

Kaptai Lake (KL), the largest inland watershed in Bangladesh (ca. 700 km2) and one of Southeast Asia’s largest artificial reservoirs, features an abundant variety of indigenous fishery species. Moreover, it provides a plethora of ecological benefits to society. Nevertheless, the KL is suffering from multidimensional natural and anthropogenic stressors that threaten these wetlands’ sustainability. Though the legal framework assures sustainable conservation of fisheries resources, the implementation scenarios of fisheries laws, regulations, and policies in the KL wetland are insufficient. This study aimed at assessing the fisher’s perception of the regulation implementation efficiency of the Protection and Conservation Fish Act of 1950, while analyzing the effectiveness of the legal framework in the context of biodiversity conservation and the management sustainability of KL. By integrating qualitative and quantitative data collected through participatory Rural Appraisal (PRA) tools viz. 225 interviews with fishers, four focus group discussions, and 12 key informant interviews, the investigation was performed in four selected areas in KL. The findings show that fishers routinely disregard laws and restrictions of the Protection and Conservation of Fish Act 1950 due to various socioeconomic and political forces. Although the annual fish harvest rate from KL appears to be increasing, the lake is losing its charismatic biological diversity primarily due to inappropriate and ineffective enforcement of fishing regulations. Many fishers believe that they still follow the act’s significant laws and regulations while being involved in several destructive and prohibited fishing practices. There is a link between community awareness, the scope of the act’s provisions, the effectiveness of its enforcement, and the strength of its execution. One of the leading causes of biodiversity loss in the KL is inadequate and ineffective fishing regulations. Improvement in the enforcement of the fishing act may be the prominent option to ensure better biodiversity conservation and sustainable management of this wetland. This result calls for functional and policy attention to revising the regulations to account for socioeconomic and political elements contributing to environmental degradation. This study also highlights the urgent need for transdisciplinary collaboration initiatives and synchronous cooperation among the agencies in order to effectively implement the fishing laws and contribute to better conservation and sustainability of the Kaptai lake fisheries resources.

Overcoming barriers to transfer of scientific knowledge: integrating biotelemetry into fisheries management in the Laurentian Great Lakes

The science–practice divide is a stubborn problem in environmental management. Existing research tells us that a range of factors affects the uptake of new science into practice and policy, including socio-organizational, individual, and evaluative variables. Here, we seek to understand the variables influencing the uptake of biotelemetry-derived information in the Laurentian Great Lakes fishery management system. To do so, we used semi-structured telephone interviews (n = 50) to capture the views of managers, researchers, and assessment biologists affiliated with the Great Lakes Fishery Commission (GLFC). Our results suggest that biotelemetry offers epistemological value (generating new and important information), but faces barriers tied to perceptions concerning practicalities of the technology, such as its cost. The practical limitations facing the use of biotelemetry evidence were more specific and potentially more easily resolved than the entrenched individual and socio-organizational challenges of using types of knowledge other than biotelemetry. The persistence of the science–practice divide was evident in our findings. Formal entities and boundary organizations such as the GLFC and inter-sectoral networks that promote interactions, meetings, and connections among researchers and practitioners can help overcome this gap. The Great Lakes Acoustic Telemetry Observation System (GLATOS) network can play a boundary role in facilitating biotelemetry science transfer by focusing on overcoming its evaluative limitations (e.g., costs, technological limitations). Further, the GLFC and GLATOS are well positioned to play a greater role in science transfer by facilitating interactions among scientists and practitioners to help reconcile differences in perceptions.

Adapting to climate change: guidance for the management of inland glacial lake fisheries

Tingley RW III, Paukert CP, Sass GG, Jacobson PC, Hansen GJA, Lynch AJ, Shannon PD. 2019. Adapting to climate change: Guidance for the management of inland glacial lake fisheries. Lake Reserv Manage. 35:435–452.Climate change is altering glacial lake fisheries in the United States, presenting a complex challenge for fisheries managers. Here we provide a regional perspective to guide management of heterogeneous and yet interdependent fishery resources in glacial lakes of the upper Midwest. Our main objective was to promote the adaptation of inland glacial lakes fisheries management to climate change by outlining processes that support regional plans. Using examples from the glacial lakes region, we outline an approach for regional prioritization, specify strategies for moving from regional prioritization to on-the-ground action, and provide guidance on the implementation of management plans given resource limitations and potential stakeholder conflict. We find that integrating ecological, social, and economic data with climate change vulnerability assessments can be useful in generating “lake-priority levels” to help identify where to focus actions to support system resilience. Managers can use lake-priority levels and ecosystem-specific strategies to make decisions about where and when to apply fisheries management action ranging from traditional (i.e., stocking, harvest regulations) to nontraditional approaches (i.e., catchment land management). Although the implementation of several approaches may be beyond an agency’s financial and logistical capacity, funds can be secured through other sources ranging from grant programs to nontraditional partnerships identified by “thinking outside the lake.” Regional plans may be an important step toward successful climate adaptation for inland glacial lakes fisheries management, and the proactive efforts of managers may help facilitate their development and implementation.

The role of a multi-jurisdictional organization in developing ecosystem-based management for fisheries in the Great Lakes basin

One of the mandated charges to the Great Lakes Fishery Commission is to facilitate the coordination of Great Lakes fishery management across jurisdictions. To do this, the Great Lakes Fishery Commission organized annual lake committee meetings among Great Lake fishery professionals since 1964. Our objective was to describe the role of the Great Lakes Fishery Commission in facilitating communication among fishery jurisdictions that fueled the development of ecosystem-based management principles in the basin. Meeting minutes from lake committee meetings and publications from the Great Lakes Fishery Commission-facilitated Salmonid Community of Oligotrophic Lakes workshop were coded based on 12 a priori ecosystem-based management principles. Meeting and workshop attendance data were analyzed through a bipartite network analysis (organizations connected to meetings) to determine if attendance at meetings were grouped, or clustered, within the fishery governance network. No significant clusters were detected, demonstrating that during 1970-75 fishery professionals in Great Lakes were cooperative in nature – in contrast to the prior half century where little cross-jurisdictional management was reported. Our analyses based on meeting attendance and coded discussions at the meetings demonstrated that three ecosystem-based management perspectives were discussed prior to 1972 (ecological integrity, hierarchical context, and humans embedded in nature) whereas discussions at lake committee meetings from 1972-74 and the Salmonid Community of Oligotrophic Lakes workshop influenced discussions about data collection, ecosystem boundaries, and hierarchical context at lake committee meetings in 1975. The Great Lakes Fishery Commission played a bridging role in facilitating communication among Great Lakes jurisdictions. These annual meetings were becoming a forum for professionals to collaboratively discuss fishery management issues, thereby advancing ecosystem-based management principles throughout the basin. Ultimately discussions at lake committee meetings helped contribute to the Great Lakes Fishery Commission and allied fishery management organizations agreeing to manage Great Lakes fisheries under ecosystem-based management through the ratification of A Joint Strategic Plan for Management of Great Lakes Fisheries in 1981.

Public perceptions of mountain lake fisheries management in national parks

The legacy of fish stocking in mountain lake ecosystems has left behind a challenge for land managers around the globe. In the US and Canada, historically fishless mountain lakes have been stocked with trout for over a century. These non-native trout have cascading ecosystem effects, and can accumulate atmospherically deposited contaminants. While the negative impacts of stocking in these ecosystems have become increasingly apparent, wilderness fishing has garnered cultural value in the angling community. As a result, public lands managers are left with conflicting priorities. National park managers across the western US are actively trying to reconcile the cultural and ecological values of mountain lakes through the development of management plans for mountain lake fisheries. However, visitors' social perceptions, attitudes, and values regarding mountain lake fisheries management have remained unquantified, and thus largely left out of the decision-making process. Our study evaluated the recreation habits, values, and attitudes of national park visitors towards fish stocking and management of mountain lakes of two national parks in the Pacific Northwest. We found that most visitors favor fish removal using a conservation approach, whereby sensitive lakes are restored, while fish populations are maintained in lakes that are more resilient. An important consideration for managers is that many mountain lake anglers consume fish on an annual basis, thus we emphasize the use of outreach and education regarding the accumulation of contaminants in fish tissues. Our findings help elucidate the conflicting views of stakeholders, and we provide recommendations to inform management of mountain lakes fisheries in North America and abroad.

Tempe Lake and Various Problems

Tempe Lake is a lake located in the western part of Wajo Regency, South Sulawesi, precisely in Tempe Subdistrict, Belawa Sub-district, Tanah Sitolo Sub-district, Maniangpajo Sub-District and Sabbangparu Sub-district, about 7 km from Sengkang City to Walanae River. Tempe Lake, which covers an area of about 13,000 hectares, has a species of freshwater fish that is rarely found elsewhere. This is because the lake is located on the slab of australia and asia. This lake is one of tectonic lake in Indonesia. Tempe Lake is supplied with water from the River of Bila and its tributaries Bulu Cenrana. In addition to supplying water, the two rivers also cause siltation due to high erosion upstream. The management of Lake Tempe fishery in Wajo Regency that is environmentally friendly must be based on the applicable law that is the Law of Ministry of Environment and the Fisheries Law. In the management of environmentally friendly fisheries, there are regulations in the Forest Management and Fisheries Law. The regulation is a process that must be done to make the management integrated into ecological and economic aspects, namely sustainable management of lake fisheries. Making of environmentally friendly fishing gear, is intended to catch the fish with a width of at least 5 cm, so the existence of fish in Lake Tempe can be sustainable without catching small fish

Contributions of Lake Erie and Lake St. Clair Walleye Populations to the Saginaw Bay, Lake Huron, Recreational Fishery: Evidence from Genetic Stock Identification

AbstractGenetic stock identification analyses were conducted to determine spawning population contributions to the recreational fishery for Walleyes Sander vitreus in Saginaw Bay, Lake Huron. Two spawning population groups were considered: (1) the Tittabawassee River, which has been identified as the largest source of spawning Walleyes for Saginaw Bay; and (2) an aggregate of six spawning populations from Lake Erie and Lake St. Clair that were found to be genetically similar. Overall, the Lake Erie and Lake St. Clair spawning populations were estimated to comprise approximately 26% of the Walleye recreational harvest in Saginaw Bay during 2008–2009. Contribution levels were similar for the 2 years in which genetic samples were collected. Contributions from the Lake Erie and Lake St. Clair spawning populations to the harvest of age‐5 and older Walleyes were greater during summer (31.8%; SE = 6.2%) than during late winter and spring (6.0%; SE = 3.7%). Conversely, contributions from the Lake Erie and Lake St. Clair spawning populations to the harvest of age‐3 and age‐4 fish were fairly similar between seasons (late winter and spring: 31.2%, SE = 6.7%; summer: 41.7%, SE = 5.6%), suggesting that younger Walleyes migrate earlier or reside in Saginaw Bay for extended periods. Our finding that one‐quarter of the Saginaw Bay recreational harvest of Walleyes comprises fish from Lake Erie and Lake St. Clair has important management implications, as policies for one lake may have bearing on the other lake—one of the challenges associated with managing migratory fish species. Fisheries management in the Laurentian Great Lakes has a history of being highly coordinated and cooperative among the states and province bordering the individual lakes. Results from this study suggest that cooperation may need to be expanded to account for fish movement between lakes.Received October 28, 2014; accepted February 11, 2015

The integration of social science information into Great Lakes fishery management: Opportunities and challenges

Fishery management is increasingly moving toward management that accounts for environmental and social dimensions. Such an approach requires the integration of natural and social science information into planning and decision-making processes. The actual integration of social science information, however, remains limited in many policy and decision-making processes within fisheries. Our study provides insights into factors that influence the intention to use social science information among fishery managers and the actual integration of such information into fishery management. Based on interviews with fishery managers in the Great Lakes, we find that the lack of social science expertise in fishery management agencies leads to multiple negative beliefs and attitudes, and subsequently a low intention to use social science information in decision-making processes. At the same time, the paper finds that more expertise in decision-making tools and basing social science on equal footing with natural sciences within fishery management institutions appears critical to advance the actual integration of social science information in fishery management.

Sensitivity of lake thermal and mixing dynamics to climate change

Warming-induced changes in lake thermal and mixing regimes present risks to water quality and ecosystem services provided by U.S. lakes and reservoirs. Modulation of responses by different physical and hydroclimatic settings are not well understood. We explore the potential effects of climate change on 27 lake “archetypes” representative of a range of lakes and reservoirs occurring throughout the U.S. Archetypes are based on different combinations of depth, surface area, and water clarity. LISSS, a one-dimensional dynamic thermal simulation model, is applied to assess lake response to multiple mid-21st century change scenarios applied to nine baseline climate series from different hydroclimatic regions of the U.S. Results show surface water temperature increases of about 77 % of increase in average air temperature change. Bottom temperature changes are less (around 30 %) for deep lakes and in regions that maintain mid-winter air temperatures below freezing. Significant decreases in length of ice cover are projected, and the extent and strength of stratification will increase throughout the U.S., with systematic differences associated with depth, surface area, and clarity. These projected responses suggest a range of future challenges that lake managers are likely to face. Changes in thermal and mixing dynamics suggest increased risk of summer hypoxic conditions and cyanobacterial blooms. Increased water temperatures above the summer thermocline could be a problem for cold water fisheries management in many lakes. Climate-induced changes in water balance and mass inputs of nutrients may further exacerbate the vulnerability of lakes to climate change.

Influence of fishing practices on lake trout bycatch in the Canadian lake-whitefish commercial fishery in Lake Huron

Rehabilitation of lake trout (Salvelinus namaycush) populations is a priority for fisheries management in the upper Laurentian Great Lakes. In Lake Huron, lake trout are frequently caught as bycatch in the commercial fishery for lake whitefish (Coregonus clupeaformis). Given the frequency of lake trout capture and the importance of limiting mortality for achieving rehabilitation goals, understanding factors that affect lake trout bycatch is valuable. We used catch and effort data from commercial logbooks and onboard observer reports to assess potential effects of factors in the operation of the lake whitefish fishery on lake trout bycatch and to develop standardized indices of lake trout abundance. Factors considered in our analysis were season, mesh size, region, and license holder, which were recorded in both datasets, and set type and depth, which were only recorded in the observer dataset. In general, we found that environmental factors affected whether lake trout bycatch occurred, but that if bycatch occurred, factors related to the fishing gear affected its magnitude. Although we observed seasonal interactions with depth and mesh size, the probability of bycatch was lowest in shallow waters, and the magnitude of bycatch was lowest in shallow waters, alternative set types, and larger mesh sizes. Standardized indices of lake trout abundance from both datasets gave comparable estimates of relative trends; an increase in abundance up to 2004–2005 followed by a decline. Our findings show utility for the use of the observer dataset from the lake whitefish fishery as part of lake trout management in Lake Huron.

Voluntary angler logbooks reveal long‐term changes in a lentic pike, Esox lucius, population

AbstractSixty‐two years of voluntarily collected angling logbook data from a large natural Danish lake were used to study variation in pike, Esox lucius L., CPUE (catch per unit effort), expressed as no. of captured pike per boat trip, as an index of stock size. Pike CPUE was positively related to pike release rate by anglers and negatively affected by certain commercial fishers. The stocking of young‐of‐the‐year pike and a fishery‐dependent index of perch, Perca fluviatilis L., abundance (which may be pike prey or predator depending on size) did not correlate with pike CPUE. Analyses of the size distribution of pike, based on sizes of annual record trophy pike captured by anglers, confirmed the negative impact of commercial pike fishing and revealed a positive influence of air temperature. It is concluded that high‐quality angler logbooks that record effort and catch can be a cost‐effective tool to inform lake fisheries management by revealing long‐term population trends. Further, state space modelling, a statistical technique not yet seen in recreational fisheries science, is recommended as a tool to model proxies for population dynamics from angler logbook data.

Lake fisheries in China: Challenges and opportunities

Chinese fisheries production (including total wild fisheries and aquaculture) went through a substantial increase from 4.3 million metric tons in 1978 to 12.4 million metric tons in 1990, and then on to 47.48 million metric tons in 2008. A similar increase was observed in lake fisheries over the same period. Lake fisheries developed from wild fisheries to stock-enhanced fisheries, and most recently, to a wide range of culture systems including intensive aquaculture. Decades of pursuing high production, with less attention paid to environmental and biological concerns, has resulted in issues related to the sustainability of the fisheries resources and the health of the lake ecosystems. Chinese lakes are now facing declining fisheries resources, eutrophication, reduced biodiversity, and increasing alien species invasions, which individually and jointly challenge lake fisheries management and policy making. However, economic prosperity and improving awareness of environmental protection and food-safety concerns have provided a new opportunity for management of lake fisheries in China.

Economic ranking of the importance of fish species to lake fisheries stocking management in Poland

This paper analyzes commercial fish stocking and catches in lakes in the 2001-2007 period. The eleven fish species that are stocked most intensely were analyzed. Rank scaling was used to compare the parameter values of the analyzed fish species. This permitted ranking all of the species from the most to the least important to lake fisheries management. Pike, Esox lucius L.; eel, Anguilla anguilla (L.); vendace, Coregonus albula (L.); and carp, Cyprinus carpio L were the highest ranked species. These were followed by tench, Tinca tinca (L.), and pikeperch, Sander lucioperca (L.), as well as whitefish, Coregonus lavaretus (L.), and common Crucian carp, Carassius carassius (L.), and Prussian carp, Carassius gibelio (Bloch). The following were of marginal significance: bighead carp, Aristichthys nobilis Rich.; silver carp, Hypophthalmichthys molitrix (Val.), wels catfish, Silurus glanis (L.), and grass carp, Ctenopharyngodon idella Val.

Future declines of the binational Laurentian Great Lakes fisheries: the importance of environmental and cultural change

It is increasingly clear that future long‐term environmental challenges (eg climate change) are being driven by economic and cultural choices, as well as by physical and biological mechanisms. We looked at the extent to which these apply to potential future changes in fisheries in the Laurentian Great Lakes. These fisheries rank among the most valuable freshwater fisheries in the world, but have declined markedly in recent decades. To investigate how these fisheries might develop in the future, we elicited projections from experts in fisheries and related fields. Experts provided assessments on variables relating to US and Canadian commercial (pounds landed) and sport (participation and expenditures) fisheries for the years 2006 and 2025. We measured each expert's ability to quantify their uncertainty, producing performance‐weighted combinations of expert estimates. All experts expected commercial fisheries to decline from 2006 to 2025, with greater declines in the US (25%) than in Canada (9%). Expectations for sport fishing differed more between lakes and less between countries, with median expected declines ranging from 1% to 13%. Experts attributed expected declines primarily to changes in economic market demands and shifts in societal interests. Increased attention to social and economic trends could aid Laurentian Great Lakes fishery policy and management.

Fishing agreements in the lower Amazon: for gain and restraint

Abstract Co‐management agreements, whereby community rules for the management of local floodplain lake fisheries are legalised and enforced by the government, have become common in the lower Amazon. Agreements are intended to limit exploitation, in particular by commercial boats, to raise stock abundance and fisheries productivity for the benefit of local subsistence‐oriented fishers and for conservation. A spatially replicated observational study was carried out to evaluate the performance of fishing agreements in terms of perceived rule compliance and actual impacts on fishing activities, catch and catch per unit of effort (CPUE, a measure of fisheries productivity and proxy for stock abundance). Perceived rule compliance was high, and this was corroborated by observed changes in fishing practices. Catch per unit of effort was significantly higher (by 48% on average) in areas subject to fishing agreements than in control areas without. Most likely this effect was attributable to the effective exclusion of mobile commercial fishing boats. Household fishing effort and catch in local communities were not significantly affected by the agreements, although a tendency towards slightly higher catches at lower effort was noticeable. In conclusion, the co‐management agreements have led to greater local control over resources and brought significant productivity and conservation benefits.

Statolith microchemistry as a technique for discriminating among Great Lakes sea lamprey (Petromyzon marinus) spawning tributaries

Laurentian Great Lakes fishery management agencies are seeking ways to identify natal origins of parasitic- and spawning-phase sea lamprey ( Petromyzon marinus ) so that efforts to control this invasive species can be prioritized. We developed laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) as a technique to quantify elemental concentrations in larval sea lamprey statoliths and explored the use of statolith microchemistry as a tool to discriminate among larval sea lamprey production streams. Our analyses demonstrate that (i) traversing across the statolith with the laser is preferable to drilling down through its apex, (ii) preserving specimens in 95% ethanol versus freezing them has minimal effects on elemental concentrations, (iii) a minimum of 15 individuals per stream should accurately depict stream-specific statolith elemental signatures, and (iv) LA-ICP-MS is preferable to particle-induced X-ray emission (PIXE) for statolith analysis, based on higher precision, lower cost, reduced sampling-time requirements, and wider availability. Using LA-ICP-MS, we could discriminate among larvae from 13 streams located in Lakes Michigan, Huron, and Superior with 82% classification accuracy, indicating that this tool holds promise for determining natal origins of sea lamprey in the Great Lakes.

Monofilament Gillnet Selectivity Parameters for European Chub (Leuciscus cephalus L.1758) in Atikhisar Reservoir, Canakkale, Turkey

Selectivity parameters of gillnets used for fish catching are very important for fisheries management in lakes. The main purpose of the present study was to estimate the selectivity parameters of monofilament gill nets mesh size of 56, 64 and 72 mm (stretched mesh size) used for European chub (Leuciscus cephalus L.1758) in Atikhisar Reservoir, Canakkale, Turkey. The indirect method proposed by Holt was used for the estimation of the selectivity parameters. The common selection factors and common standard deviation of monofilament gill nets were determined as 4.25 and 2.37, respectively. For sustainable fisheries of European chub, the minimum mesh size of monofilament gill nets must be greater than 47 mm stretched mesh size.

Restoring the chambo in Southern Malawi: Learning from the past or re-inventing the wheel?

Chambo is an important fish to Malawi's economy and to the livelihoods of local people in the southern end of Lake Malawi. Overexploitation of the chambo has been a source of concern since the 1930s. The biological and economic collapse of the fishery in Lake Malombe and the Upper Shire River in the early 1990s, and growing evidence in recent years of its decline in the Southeast Arm of Lake Malawi (the major productive area for the species) have galvanised the Government of Malawi into making an attempt to restore the chambo to former levels of production. This paper argues that while the proposed solutions for restoring the chambo might be well intentioned, they nevertheless ignore existing knowledge and scholarship about fisheries management in African freshwater lakes gathered over the last six decades. A body of knowledge on the biological and scientific basis for regulating the chambo already exists. The missing link is an understanding and appreciation of the social, economic, political and institutional drivers on exploitation patterns of the chambo. Future management solutions must be based on the collective concerns of all potential users. More specifically, such solutions should be cognisant of local knowledge, fishers' experiences and the way they view and define their problems. If these are disregarded, finding solutions to the enormous challenge of restoring chambo stocks to their former status will be as difficult as grappling in the dark.

Human Dimensions of Great Lakes Fishery Management: New Research Thrust of the Great Lakes Fishery Commission

ABSTRACT The Great Lakes Fishery Commission, recognizing the importance of social impacts on Great Lakes fisheries and the shortage of information on “human dimensions,” launched a new research theme. It seeks to fill knowledge gaps in the areas of legal and institutional frameworks governing fisheries, constructing effective processes that better inform management decision making, and the role and impact of stakeholder involvement in Great Lakes fisheries management.