On food security and access to fish in the Saugeen Ojibway Nation,Lake Huron,Canada

This exploratory study offers insights to the complex relationships between accessing local fisheries and food security in the traditional territory of the Saugeen Ojibway Nation (SON), Lake Huron, Canada. Based in qualitative research, including focus groups and key informant interviews conducted in the SON community in summer 2016, we identify the inter-related structural and relational mechanisms influencing the ability of SON community members to derive food security benefits, including culturally appropriate and nutritious diets and sustainable livelihoods, from local fisheries. There is, however, a need for ongoing efforts to better link the fisheries management, economic and cultural development, and traditional food access objectives of the community, ideally through better connecting and managing existing social networks.     

Nearshore fish assemblage dynamics in southern Lake Michigan: 1984–2016

Many coastal ecosystems, including those of the Laurentian Great Lakes, suffer from various natural and anthropogenic stressors. Given that multiple stressors often concomitantly impact ecosystems, it may be difficult to disentangle which stressors are most influential. Upper trophic level communities, such as fish assemblages, can provide insights to the influence of diverse stressors as they may integrate cumulative effects over the long-term and also reflect responses of lower trophic levels. We used multivariate analyses and assemblage indices to investigate long-term (1984–2016) patterns in a nearshore fish assemblage indexed via annual trawling in the Indiana waters of southern Lake Michigan. Based on observations from other regions of the Great Lakes, we expected that oligotrophication, due to reduced nutrient loading and filtering by invasive mussels, would have a strong influence on the fish assemblage. However, we were unsure if the very nearshore fish assemblage would track observed decreased production patterns in offshore Lake Michigan or if observed increased primary production in the very nearshore would affect the fish assemblage. Consistent with the former expectation, overall abundance and richness of the assemblage declined over time. However, contrary to observations in other regions there was no overall evidence of species tolerant to more eutrophic conditions being replaced by more sensitive species. Moreover, there was limited evidence of the fish assemblage shifting towards species more tolerant of warm water, as might be expected with climate change. While increased numbers of invasive species added species to the system, overall species richness and native species richness declined.     

Paradigm shifts required to promote ecosystem modeling for ecosystem-based fishery management for African inland lakes

Ecosystem-based fishery management (EBFM) is the best option where other fishery management objectives have failed. This makes EBFM important for the African inland lakes and fisheries resources that are among the most threatened in the world despite existing management interventions. Ecosystem modeling provides information that guides EBFM, and, to promote EBFM for the African inland lakes and fisheries, we present strategies required to promote ecosystem modeling. The strategies are based on an examination, presented herein, of (i) publication trends in literature applying two leading aquatic ecosystem modeling platforms, Ecopath with Ecosim (EwE) and Atlantis, on the African Great Lakes as representatives of African inland lakes and (ii) deficiencies in data eminent in ecosystem models existing on these lakes. The examination indicated that ecosystem modeling is inactive on the African Great Lakes, and there is limited local and regional capacity for ecosystem modeling with existing models predominantly led by foreign researchers and marred by data deficiencies. The implications of these observations for ecosystem modeling and EBFM for the African Great Lakes are discussed. The strategies required to promote ecosystem modeling include supporting short-term training workshops to equip local scientists with basic skills for ecosystem modeling, mainstreaming ecosystem modeling in fisheries training curriculum of local universities, and conducting data collection surveys to fill data deficiencies. These are envisaged to increase capacity and activate ecosystem modeling, and consequently promote EBFM.     

Metrics of ecosystem status for large aquatic systems – A global comparison

We identified an objective set of 25 commonly available ecosystem metrics applicable across the world's large continental freshwater and brackish aquatic ecosystem. These metrics measure trophic structure, exploited species, habitat alteration, and catchment changes. We used long-term trends in these metrics as indicators of perturbations that represent an ecosystem not in homeostasis. We defined a healthy ecosystem as being in a homeostatic state; therefore, ecosystems with many changing trends were defined as more disturbed than ecosystems with fewer changing trends. Healthy ecosystems (lakes Baikal, Superior, and Tanganyika) were large, deep lakes in relatively unpopulated areas with no signs of eutrophication and no changes to their trophic structure. Disturbed ecosystems (lakes Michigan, Ontario, and Victoria) had shallow to moderately deep basins with high watershed population pressure and intense agricultural and residential land use. Transitioning systems had widely varying trends and faced increasing anthropogenic pressures. Standardized methodologies for capturing data could improve our understanding of the current state of these ecosystems and allow for comparisons of the response of large aquatic ecosystems to local and global stressors thereby providing more reliable insights into future changes in ecosystem health.     

The 2017 African Great Lakes Conference: Conservation and development in a changing climate

In May 2017, the African Great Lakes community convened for a region-wide conference in Entebbe, Uganda. The African Great Lakes Conference (AGLC) focused on 6 regionally-important themes, and 300+ attendees presented over 100 talks and posters. The AGLC culminated in the adoption of a set of Conference Resolutions designed to direct the future of African Great Lakes conservation and management. As an Introduction to this Journal of Great Lakes Research special section on African Great Lakes, we report on the impetus for the African Great Lakes Conference as well as discuss three major advances and investments that were a direct result of conference resolutions adopted at the meeting. First, we present the AGLC Resolutions, a set of management issues and solutions developed at the conference. Second, we discuss the African Great Lakes Conference Fund, a conservation fund that has awarded $500,000 USD to launch four new initiatives. Finally, we describe African Great Lakes Inform, a knowledge management platform designed to promote collaboration in the region. The AGLC in general, and these three major conference outcomes specifically, provide a set of basic building blocks to advance partnerships, research and capacity in the African Great Lakes region.     

Ecosystem-based fisheries management is attainable,affordable, and should be viewed as a long-term commitment: Experiences from Lake Vättern,Sweden

Lake Vättern is Sweden’s second largest lake and faces multiple environmental challenges such as climate change, pollutants and invasive alien species. Since its foundation in 1957, the Lake Vättern Society of Water Conservation (LVSWC) has been a local actor aiming to manage a broad range of environmental issues concerning the lake and its catchment. Stakeholders can be members of LVSWC, which also organises a fisheries co-management group mainly dealing with fisheries issues. Ecosystem-based fisheries management (EBFM) is a widely desired framework shaped to focus on ecosystems, involve stakeholders, and address environmental issues in an adaptive, integrated and holistic manner while also including societal aspects. We have investigated how the management of Lake Vättern relates to 15 central principles for EBFM. The study found that LVSWC and the fisheries co-management group work along and towards the EBFM principles in a locally adapted way. Several environmental improvements have been observed concurrently with LVSWC activity, such as increased water clarity, and a strengthened stock of the Arctic char (Salvelinus alpinus). Long-term commitment by European, national and regional authorities was seen as essential to maintain and improve EBFM functions for Lake Vättern, to ensure continuity in the work, rather than having to depend on short projects. Becasue literature examples of EBFM in lakes are scarce worldwide, this study provides a unique example of the pursuit of EBFM in lake ecosystem management.     

Revisiting the Great Lakes Water Quality Agreement phosphorus targets and predicting the trophic status of Lake Michigan

LM3-Eutro is a high-resolution eutrophication model with several improved features lacking in historical Great Lakes models. We calibrated LM3-Eutro using a 2-year (1994-1995) dataset and performed a hindcast simulation from 1976 to 1995 to evaluate the model's ability to make predictions over an extended period of time. Results show a reasonable agreement between model output and field data over this time period. The model predicted that an annual loading of 5600 metric tons (MT) would result in a lake-wide annual total phosphorus (TP) concentration of 7.5 μg L^− 1. Using best estimates of future TP loadings, LM3-Eutro forecasts suggest that Lake Michigan will remain oligotrophic and will continue to meet the 7 μg L^− 1 spring TP concentration Great Lakes Water Quality Agreement objective.     

The flathead catfish invasion of the Great Lakes

A detailed review of historical literature and museum data revealed that flathead catfish were not historically native in the Great Lakes Basin, with the possible exception of a relict population in Lake Erie. The species has invaded Lake Erie, Lake St. Clair, Lake Huron, nearly all drainages in Michigan, and the Fox/Wolf and Milwaukee drainages in Wisconsin. They have not been collected from Lake Superior yet, and the temperature suitability of that lake is questionable. Flathead catfish have been stocked sparingly in the Great Lakes and is not the mechanism responsible for their spread. A stocking in 1968 in Ohio may be one exception to this. Dispersal resulted from both natural range expansions and unauthorized introductions. The invasion is ongoing, with the species invading both from the east and the west to meet in northern Lake Michigan. Much of this invasion has likely taken place since the 1990s. This species has been documented to have significant impacts on native fishes in other areas where it has been introduced; therefore, educating the public not to release them into new waters is important. Frequent monitoring of rivers and lakes for the presence of this species would detect new populations early so that management actions could be utilized on new populations if desired.     

Impacts on biodiversity and species changes in the lower Great Lakes

The Great Lakes basin ecosystem evolved after the retreat of the last ice sheet, about 10 000 years ago. Today, the complex of species present in the Great Lakes and much of the visible landscape bears little resemblance to that found some 400 years ago. Rather, the effects of various aspects of human development have caused major changes in the natural biodiversity. Lessons learned in the lower Great Lakes are applicable to many lakes around the world that have undergone agricultural, industrial and urban development in their drainage basins and have become managed, artificial ecosystems.