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Freshwater biodiversity loss in the Anthropocene escalates the need for successful environmental water management to sustain human benefitting ecosystem services. Of the world’s river basins, one-third are now severely water depleted, rendering the quality and quantity of water to maintain or restore freshwater ecosystem integrity increasingly urgent. However, managing environmental water is intricate because of complexity and uncertainty in interacting social and biophysical system components, and trade-offs between costs and benefits of implementing environmental flows. Learning enabled adaptive management – embracing the uncertainty – is essential; however, practising adaptive management (worldwide) is challenging; single-, double- and triple-loop learning is required, along with social learning, to tackle complex problems. There is progressive realisation of environmental flows (Ecological Reserve) in the Crocodile River, South Africa, linked to the Kruger National Park, using Strategic Adaptive Management (SAM). In this research article, we reflected on adaptive (single- and double-loop) learning and transformative (triple-loop) learning capacity emergent in SAM between 2009 and 2019 whilst also considering social learning potentials. We found evidence of preconditions (e.g. transparency) for social learning within a burgeoning stakeholder ‘community-of-practice’, likely fostering capacities (e.g. information sharing) for sustained social learning. Adaptive and transformative learning is enabled by social learning, underpinned by ongoing nested feedbacks supporting assessment and reflection, which facilitates single-, double- and triple-loop learning. Champions exist and are vital for sustaining the adaptive management system. Executing adaptive and transformative learning aids in positive change across the range of ecological, social and economic outcomes that are essential for success in environmental water programmes, worldwide. Conservation implications: Crocodile River Ecological Reserve implementation, associated with Kruger National Park, provided an important national precedent (lessons) for protecting the ecological integrity of river systems – obligatory under the National Water Act (Act No 36 of 1998). We demonstrated the importance of ongoing stakeholder learning for successful management of the Ecological Reserve.

The Malkumba-Coongie Lakes Ramsar Site has extensive terrestrial and freshwater ecosystems (largest Ramsar Site in Oceania, 2,178,952 ha, designated in 1987), including freshwater and salt lakes, lignum swamps and river channels in central Australia. It is supplied by Cooper Creek, a free-flowing Lake Eyre Basin river system. The area includes pastoral leases (97% of site grazed, including a regional conservation reserve (35%)) and a National Park (3%), with the largest oil and gas production field in Australia. We developed a Strategic Adaptive Management (SAM) Plan, linking science, monitoring and management of this social-ecological system, involving stakeholders and workshops. This involved developing a shared vision and hierarchy of objectives linked to management actions and identified outputs and outcomes. We exemplify this approach with explicit and measurable end-points (thresholds of potential concern) culminating from low level objectives for fish communities, particularly the alien sleepy cod Oxyeleotris lineolata. We describe this framework, highlighting the benefits in prioritizing management actions and monitoring in collaboration with a diverse range of stakeholders, driving adaptive feedback for learning. The whole approach is aimed at successfully achieving mutually agreed management objectives and the vision to maintain the ecological character of the Malkumba-Coongie Lakes Ramsar Site.

Most intermittent rivers and ephemeral streams (IRES) are managed for their water resources, ecosystem services, and/or environmental values but seldom as a social-ecological system. The spatial connectivity of IRES across a catchment makes them particularly complex social-ecological systems where there are interlinking social and governance processes with the ecological dimensions. Increasingly, there is realization that adaptive management of such social-ecological systems requires transparent articulation of a desired state, guided by a vision and supported by explicit objectives. We compared implementation of Strategic Adaptive Management of IRES and their catchments in four case studies from South Africa (Kruger National Park and Tankwa Karoo National Park) and Australia (Macquarie Marshes and Edward-Wakool system). There were commonalities and differences reflected in their different values and identification of key attributes as well as the idiosyncrasies of different drivers, including anthropogenic drivers. Effective implementation still represents an aspiration for many but a potentially effective way of identifying priorities for management, transparently supported by scientific monitoring and reporting.

The complex nature of freshwater systems provides challenges for incorporating evidence-based techniques into management. This paper investigates the potential of participatory evidence-based techniques to involve local stakeholders and make decisions based on different "knowledge" sources within adaptive management programs. It focuses on the application of thresholds of potential concern (TPC) within strategic adaptive management (SAM) for facilitating inclusive decision-making. The study is based on the case of the Edward-Wakool (E-W) "Fish and Flows" SAM project in the Murray-Darling River Basin, Australia. We demonstrate the application of TPCs for improving collaborative decision-making within the E-W, associated with environmental watering requirements, and other natural resource management programs such as fish stocking. The development of TPCs in the E-W fish and flows SAM project helped improve stakeholder involvement and understanding of the system, and also the effectiveness of the implemented management interventions. TPCs ultimately helped inform environmental flow management activities. The TPC process complemented monitoring that was already occurring in the system and provided a mechanism for linking formal and informal knowledge to form explicit and measurable endpoints from objectives. The TPC process faced challenges due to the perceived reduction in scientific rigor within initial TPC development and use. However, TPCs must remain tangible to managers and other stakeholders, in order to aid in the implementation of adaptive management. Once accepted by stakeholders, over time TPCs should be reviewed and refined in order to increase their scientific rigor, as new information is generated.

Large infrequent disturbances (LIDs) leave heterogeneous, patchy legacies because the event may have different severities in different locations, or may influence ecosystem components differently. Biotic and abiotic legacies form the template upon which subsequent ecological processes take place and thus, LIDs can have a long-lasting influence on ecosystems. This study determined the geomorphological (channel type), landscape state (mosaic of physical and riparian vegetation patches) and riparian vegetation legacies of an extreme flood in the Sabie River. The linear proportions of geomorphological channel types were altered by the flood because of complex patterns of sediment erosion and deposition related to bed slope and channel width. Biotic landscape states (tree, shrub, reed, herbaceous vegetation) were stripped to expose the underlying physical template. The persistence and arrangement of landscape states varied amongst channel types because of the interaction between flood flows and the geomorphological attributes of each channel type. Overall, some riparian species decreased in density because of removal by the flood, and some increased in density because of post-flood recruitment or re-establishment. The flood also changed the location of many species in relation to their characteristic pre-flood elevation within the channel. In accordance with the expectations of LIDs, the effects of the flood were not uniform. Instead, the flood left a legacy of juxtaposed biotic and abiotic components that varied spatially amongst channel types and at different elevations within the channel.

The roan antelope (Hippotragus equinus) population inhabiting the Kruger National Park, South Africa, declined from 450 animals in 1986 to around 25 free-ranging animals subsequent to 1994. A computer simulation model was developed to: (1) evaluate likely contributions of low rainfall, habitat deterioration, population fragmentation and predation to the observed population decline; (2) project future likelihood of persistence of the population remnant, under various scenarios. Direct consequences of severe drought and habitat deterioration alone were inadequate to explain the observed decline, unless effects were more severe than assumed in the model. An increased predation loss to around 30% per year was needed. Persistence probability over 50 years was less than 0.5 if the predation loss remained above 20% per year. Models that take into account only stochastic uncertainty in demography and environmental variability are of limited reliability if potential changes in predation risk are not also accommodated.

The Kruger National Park’s (KNP) adopted system of management, called Strategic Adaptive Management (SAM), originated during the Kruger National Park Rivers Research Programme (KNPRRP) of the 1990s. An important concept in SAM is the thresholds of potential concern (TPCs), representing end-points in a continuum of change. TPCs within the KNP SAM system guide management if or when reached, ‘red-flagging’ possible negative biodiversity impacts and catalysing consideration of management options. TPC-related monitoring generates the strategic information for ongoing evaluation, learning and adaptation within SAM. Post- KNPRRP, although river flow and water quality TPCs have been implemented partly, those designed to detect undesirable changes in biodiversity have not been implemented, until recently. This paper describes the history, rationale, application and ongoing developments associated with the KNP river TPCs over the last decade, providing some key lessons for organisations utilising SAM. The paper concludes with an overview of new thinking and future directions envisaged for the KNP river TPCs, as part of the KNP SAM system. Conservation implications: This paper documents important concepts of strategic adaptive management associated with the KNP river systems. Understanding, related to the rationale and justification for use and development or refinement of the thresholds of potential concern, lays an important foundation for ongoing work in managing these rivers adaptively.

The availability of suitable patches and gaps in the landscape is a crucial determinant of invasibility for alien plants. The type and arrangement of patches in the landscape may both facilitate and obstruct alien plant invasions, depending on whether alien species perceive the patches as barriers. In February 2000 tropical weather systems caused an extreme flood with an estimated return interval of 90 to 200 years in the Sabie River, South Africa. The impact of the 2000 flood on the Sabie River landscape provides an array of patches that may provide suitable resources for the establishment of alien plants. This study examines the distribution of alien plants in relation to patchiness of the Sabie River landscape. Our hypothesis was that if certain patches in the river landscape do not represent environmental barriers to alien plant invasion, alien species will occur preferentially in these patch types. The Sabie River within Kruger National Park [KNP] was divided into six patch types (zones, channel types, elevations, geomorphic units, substrates and flood imprint types). We then examined the distribution of native and alien woody and herbaceous density and species richness in patches. The density and species richness of alien plants in the Sabie River in KNP is very low when compared to the density and species richness of native plants. Some patches (bedrock distributary and braid bar geomorphic units) contained higher density and richness of alien plants compared to the other patches examined, indicating that these locations in the river landscape offer the resources necessary for alien plant establishment. Individual alien species are also associated with different parts of the river landscape. Failure of large numbers of alien plants to establish after the 2000 flood is most likely due to a combination of factors—the plant specific barriers imposed by landscape patchiness, the high abundance and richness of native vegetation leading to competition, and for some species certainly, the clearing by the management (Working for Water) programme., The copyright policy for South African Journal of Botany (ISSN: 0254-6299) accessed on Sherpa-Romeo on 17-05-2018 allows the archiving of the post-print on open access repository after an embargo period of between 12 months and 48 months and does not allow the use of publisher’s version/PDF on the institutional repository. Must link to publisher version with DOI. Author's post-print must be released with a Creative Commons Attribution Non-Commercial No Derivatives License.

Studies of large infrequent disturbances, such as the Mount St Helens volcanic eruption, the 1988 Yellowstone National Park fires, and Hurricane Hugo, show that such events leave a heterogeneous imprint on a landscape, and that this imprint subsequently influences ecological response. But what imprint does a large infrequent flood disturbance leave on a river landscape, and how does the imprint influence river ecosystem response to disturbance? We used a landscape ecological framework to examine the associations between the imprint of an extreme flood and the response of woody riparian vegetation in the Sabie River (Kruger National Park, South Africa) landscape. We found that the flood left a heterogeneous imprint, consisting of remnant vegetated patches, remnant physical patches, and newly created physical patches. The structure and composition of riparian vegetation assemblages subsequently differed among these patches. Heterogeneity of the river landscape mosaic may result in multiple trajectories of e...