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Abstract: Freshwaters ecosystems continue to face pressures from pollution, flow regime alterations, habitat destruction and exotic species invasions despite their unique biodiversity. In Europe, National Parks and Special Areas of Conservation aim to provide protection of ‘aggregate’ biodiversity, yet inspection of priority species lists for these sites often reveals a focus towards terrestrial species. In regions such as the Alps and the Pyrénées, this is a particularly serious problem because climate change and other anthropogenic pressures (e.g. hydropower, tourism) are causing widespread hydrological modification which is likely to drive changes in aquatic species abundance, diversity and distribution. Improved understanding of the diversity of rare plants and animals is necessary so efforts can be cost-effectively targeted to conserve the maximum number of species, whilst a clearer picture of these species’ distributions is a precursor to targeting conservation efforts. This paper reports results of a study into the diversity and distribution of 17 endemic mayflies, stoneflies and caddisflies from 598 rivers sites across southern France. Endemic macroinvertebrates were found only at sites in the Pyrénées mountain range with richness peaking at 1500–1800m above sea level. Nine of these 17 species were recorded from <20 sites and two (Protonemura angelieri, Rhithrogena kimminsi) were found at only 10 sites. Despite both the rarity of these species and threats to their existence, none of them have any current conservation status. New conservation policies for freshwater ecosystems in the French Pyrénées need to be developed as a priority due to the rarity of many aquatic species in this area, growing threats to their existence (habitat modification, hydrological change), and to recognise their importance in food webs that may include other rare species of conservation value. [Copyright &y& Elsevier]

Climate change can lead to habitat loss and degradation, and consequently endangers species in a specific region. Besides addressing the priority areas of species distribution, an urgent consideration is to identify suitable conservation options and map areas according to their effectiveness when planning to conserve a rare species under climate change. Here, we conducted a study to develop potential conservation strategies and assess their effectiveness under different climate scenarios in Sanjiang (“Three rivers” in English) Plain (Amur, Ussuri and the Songhua Rivers) of Northeast China. We used the species distribution software MaxEnt to model current and future habitat distributions of endangered oriental white storks ( Ciconia boyciana ). Based on field surveys, experts' knowledge and literature findings, we developed the methods to identify conservation strategies. By including additional species presence sites derived from conservation strategies (a presumption of the further analyses) into MaxEnt, we predicted the future habitat distribution under the implementation of different conservation strategies. To estimate the effect of conservation strategies, we compared the differences in the extent of suitable habitat with and without conservation strategies under two different predicted climate change scenarios. The results showed that the suitable habitat of the oriental white stork in the study region dramatically declined by over 80% in the absence of conservation strategies under both scenarios. Predicted suitable habitats with conservation strategies had broader distribution ranges than those without. The strategy of reclaiming cropland back to wetland offers the most impressive effectiveness with a tenfold increase in suitable habitat, followed by the strategy of establishment of nature reserves with six fold and the strategy of artificial bird nest with two fold increase. Our approaches emphasize the effect of integration of knowledge of experts in conjunction with MaxEnt when mapping and assessing the effect of the conservation strategies. [ABSTRACT FROM AUTHOR]

Drought is an important natural disturbance that influences community structure by altering species composition, abundance, and richness. Human-induced alterations of the hydrologic cycle and climate change can exacerbate the impact of drought, potentially leading to species extirpations and changes in community structure. These changes in community structure can lead to substantial alterations and losses of ecosystem functions. Nutrient recycling is an important ecosystem function that helps modify rates of production and food web structure. Animals are important in cycling and storing nutrients in aquatic ecosystems through feeding, growth, and excretion. Freshwater mussels are long-lived animals, often living more than 20 years, and perform important ecosystem functions such as nutrient storage and cycling. Mussels dominate benthic biomass in many aquatic systems, and thus can be an essential component affecting nutrient dynamics. Unfortunately, they are experiencing rapid declines. In this study, we surveyed freshwater mussel populations across nine sites in three rivers in the south-central U.S. immediately before and after an exceptional, regional drought. We characterized the hydrological severity of the drought and estimated mussel biomass loss and the consequent loss of mussel-provided nutrient cycling and storage. We determined if losses differed between mussel thermal guilds and how such losses might influence nutrient dynamics and stoichiometry. Additionally, we investigated whether losses caused by the drought were intensified by different land cover types. Our surveys indicated that there were declines in both density and biomass of mussels, and greater losses were associated with areas that had less forest cover. This die-off resulted in a lower availability of N and reduced P storage by freshwater mussels in these rivers, potentially altering system nutrient availability. Additionally, our analyses showed that thermally sensitive species have lower tissue N:P. Thus, our results show that differences in species tolerance to drought may lead to varying storage and release of nutrients. Further studies incorporating net flux and storage will allow scientists to better understand the repercussions of species loss to ecosystem function. [ABSTRACT FROM AUTHOR]

Abstract: Turkey (Türkiye) lies at the nexus of Europe, the Middle East, Central Asia and Africa. Turkey’s location, mountains, and its encirclement by three seas have resulted in high terrestrial, fresh water, and marine biodiversity. Most of Turkey’s land area is covered by one of three biodiversity hotspots (Caucasus, Irano-Anatolian, and Mediterranean). Of over 9000 known native vascular plant species, one third are endemic. Turkey faces a significant challenge with regard to biodiversity and associated conservation challenges due to limited research and lack of translation into other languages of existing material. Addressing this gap is increasingly relevant as Turkey’s biodiversity faces severe and growing threats, especially from government and business interests. Turkey ranks 140th out of 163 countries in biodiversity and habitat conservation. Millennia of human activities have dramatically changed the original land and sea ecosystems of Anatolia, one of the earliest loci of human civilization. Nevertheless, the greatest threats to biodiversity have occurred since 1950, particularly in the past decade. Although Turkey’s total forest area increased by 5.9% since 1973, endemic-rich Mediterranean maquis, grasslands, coastal areas, wetlands, and rivers are disappearing, while overgrazing and rampant erosion degrade steppes and rangelands. The current “developmentalist obsession”, particularly regarding water use, threatens to eliminate much of what remains, while forcing large-scale migration from rural areas to the cities. According to current plans, Turkey’s rivers and streams will be dammed with almost 4000 dams, diversions, and hydroelectric power plants for power, irrigation, and drinking water by 2023. Unchecked urbanization, dam construction, draining of wetlands, poaching, and excessive irrigation are the most widespread threats to biodiversity. This paper aims to survey what is known about Turkey’s biodiversity, to identify the areas where research is needed, and to identify and address the conservation challenges that Turkey faces today. Preserving Turkey’s remaining biodiversity will necessitate immediate action, international attention, greater support for Turkey’s developing conservation capacity, and the expansion of a nascent Turkish conservation ethic. [Copyright &y& Elsevier]

Climate change is projected to alter river discharge in every populated basin in the world. In some parts of the world, dam removal now outpaces their construction and the diminishing cost efficiency of dams in drying regions is likely to further increase the rate of removals. However, the potential influence of climate change on the impact of dam removals has received almost no consideration. Most dams have major biological and ecological impacts and their removal would greatly benefit riverine ecosystems. However, using model regions in the Southern Hemisphere, we highlight that artificial lentic habitats created by dams can act as refuges for increasingly imperiled freshwater fishes, and dams may also prevent the upstream spread of invasive alien species in rivers. We argue that, in these and other regions where the major impact of climate change will be to reduce streamflow and aquatic refuge availability, a shifting balance between the negative and positive environmental impacts of dams requires policy makers to include climate change predictions in prioritisation processes for dam removal. [ABSTRACT FROM AUTHOR]

The effects of climate and land-use change, coupled with limited management resources, mean that managers are increasingly faced with decisions to invest in some locations at the expense of others. Given their potentially controversial nature, such decisions require predictions of likely outcomes under different management strategies and potential future climates. We develop an approach to prioritise management interventions across multiple locations in highly variable and uncertain environments, using a stochastic model of population dynamics structured to include the (dynamic) effects of environmental conditions on key vital rates. We demonstrate this approach with a case study on the endangered Australian freshwater fish, the Macquarie perch (Macquaria australasica), assessing the effectiveness of seven management interventions under five scenarios of deterministic climate change. All management interventions were predicted to improve Macquarie perch population outcomes (increased abundances, reduced risk of quasi-extinction), with the risk of declines lowest when management included augmented gene flow and enforcement of fishing regulations. The lowest levels of risk occurred in locations with stable environmental conditions, which suggests that reintroducing Macquarie perch to large, regulated rivers with suitable access to spawning habitat may be more beneficial than investment in small, unregulated streams where populations were unlikely to persist under any scenario. Population reintroductions provide opportunities to shift populations from water-stressed to water-secure locations where required (e.g. to preserve unique genetic diversity). This finding likely applies to many aquatic species, and highlights a potential need to supplement threat mitigation in water-stressed locations with efforts to establish new populations in water-secure locations. • Environmental variability threatens aquatic populations in water-stressed locations. • Conservation may require shifts from water-stressed to water-secure locations. • Augmented gene flow is an important and highly beneficial management intervention. • Population models can identify conservation priorities in dynamic environments. [ABSTRACT FROM AUTHOR]

There is growing evidence that as a consequence of climate change the frequency of extreme hydrological events will increase. Predicting the impacts of these extreme events on ecological systems is a major research challenge. It is predicted that change in future river flows, characterised by greater occurrence of floods and droughts, will have profound impacts on aquatic invertebrate communities by removing sensitive species and restructuring food networks. However, it remains unclear how an increase in these hydrological extremes will impact on riparian communities and species at higher trophic levels. Here, we describe a new methodology that facilitates the integration of quantitative outputs of species' distribution models with the expert knowledge of conservation practitioners to produce a species' vulnerability index (SVI). Using our SVI framework, we assessed and ranked the vulnerability of 16 river bird species to a potential climate-induced shift in the frequency, duration and magnitude of flood and drought events. Vulnerability was associated primarily with ecological traits that restrict species to in-channel riverine habitat. Whilst the SVI was developed to assess species' vulnerability to hydrological extremes on rivers, it is equally applicable to other environmental domains as well as a range of avian and non-avian taxa. Furthermore, this original methodological approach provides researchers and managers with a valuable conservation tool that allows them to identify the species most vulnerable to climate change impacts and plan mitigation and adaptation strategies. [ABSTRACT FROM AUTHOR]

Lotic ecosystems harbor a disproportionate amount of global biodiversity, but continue to experience extinction rates greater than terrestrial. Alpine rivers and streams are especially threatened due to high rates of warming, glacier melt impacts, landcover change, and impoundment. Lack of monitoring, however, hampers conservation efforts in many regions. The Hindu-Kush Himalaya (HKH) is experiencing rapid environmental change, but impacts on aquatic biodiversity are unknown. Using a unique long-term dataset, we investigated changes to local (alpha) and regional (gamma) fish species diversity across 38 sites on Nepal's Kaligandaki-Narayani River (KNR), and evaluated potential impacts of climate change. Our results indicate a significant decrease in mean abundance and local species richness, although regional diversity did not decline. Species ranges contracted between the 1990s and 2010s, with lower bounds and weighted means shifting to higher elevations. Range shifts coincided with water temperature warming between the 1990s and 2010s, particularly at more speciose lower elevation sites. Although widespread species loss has not yet occurred, decreasing abundance and contraction of species' ranges point to increased extirpation risk in the near future. Our results suggest that effective conservation strategies must identify and preserve thermal refugia, maintain habitat connectivity, manage terrestrial protected areas so that aquatic biodiversity also benefits, and establish sustainable fishery harvests to protect species diversity in the KNR and other threatened, under-studied alpine biodiversity hotspots. [ABSTRACT FROM AUTHOR]

Abstract: The conservation challenges facing mega-biodiverse South and Southeast Asia in the 21st century are enormous. For millennia, much of the habitat of these regions was only lightly modified by human endeavour, yet now it is experiencing rampant deforestation, logging, biofuel cropping, invasive species expansion, and the synergies of climate change, drought, fire and sea-level rise. Although small-scale conservation management might assist some species and habitats, the broader sweep of problems requires big thinking and some radical solutions. Given the long expected lead times between progressive economic development and stabilization of human population size and consumption rates, we argue that ‘technological fixes’ cannot be ignored if we are to address social and fiscal drivers of environmental degradation and associated species extinctions in rapidly developing regions like southern Asia. The pursuit of cheap and abundant ‘clean’ energy from an economically rational mix of nuclear power, geothermal, solar, wind, and hydrogen-derivative ‘synfuels’, is fundamental to this goal. This will permit pathways of high-tech economic development that include intensified (high energy-input) agriculture over small land areas, full recycling of material goods, a transition from fossil-fuel use for transport and electricity generation, a rejection of tropical biofuels that require vast areas of arable land for production, and a viable alternative to the damming of major waterways like the Mekong, Murum and northern tributaries of the Ganges and Brahmaputra Rivers for hydroelectricity. Rational approaches that work at large scales must be used to deal with the ultimate, rather than just proximate, drivers of biodiversity loss in the rapidly developing regions of southern Asia. [Copyright &y& Elsevier]

Abstract: Land ownership in Alaska includes a mosaic of federally managed units. Within its agency’s context, each unit has its own management strategy, authority, and resources of conservation concern, many of which are migratory animals. Though some units are geographically isolated, many are nevertheless linked by paths of abiotic and biotic flows, such as rivers, air masses, flyways, and terrestrial and aquatic migration routes. Furthermore, individual land units exist within the context of a larger landscape pattern of shifting conditions, requiring managers to understand at larger spatial scales the status and trends in the synchrony and spatial concurrence of species and associated suitable habitats. Results of these changes will determine the ability of Alaska lands to continue to: provide habitat for local and migratory species; absorb species whose ranges are shifting northward; and experience mitigation or exacerbation of climate change through positive and negative atmospheric feedbacks. We discuss the geographic and statutory contexts that influence development of ecological monitoring; argue for the inclusion of significant amounts of broad-scale monitoring; discuss the importance of defining clear programmatic and monitoring objectives; and draw from lessons learned from existing long-term, broad-scale monitoring programs to apply to the specific contexts relevant to high-latitude protected areas such as those in Alaska. Such areas are distinguished by their: marked seasonality; relatively large magnitudes of contemporary change in climatic parameters; and relative inaccessibility due to broad spatial extent, very low (or zero) road density, and steep and glaciated areas. For ecological monitoring to effectively support management decisions in high-latitude areas such as Alaska, a monitoring program ideally would be structured to address the actual spatial and temporal scales of relevant processes, rather than the artificial boundaries of individual land-management units. Heuristic models provide a means by which to integrate understanding of ecosystem structure, composition, and function, in the midst of numerous ecosystem drivers. [Copyright &y& Elsevier]

Freshwater ecosystems are declining under climate change and land-use change. To maximize the return on investment in freshwater conservation with limited financial resources, managers must prioritize management actions that are most cost-effective. However, little is known about what these priorities may be under the combined effects of climate and land-cover change. We present a novel decision-making framework for prioritizing conservation resources to different management actions for the conservation of freshwater biodiversity. The approach is novel in that it has the ability to model interactions, rank management options for dealing with conservation threats from climate and land-cover change, and integrate empirical data with expert knowledge. We illustrate the approach using a case study in South East Queensland (SEQ), Australia under climate change, land-cover change and their combined effects. Our results show that the explicit inclusion of multiple threats and costs results in quite different priorities than when costs and interactions are ignored. When costs are not considered, stream and riparian restoration, as a single management strategy, provides the greatest overall protection of macroinvertebrate and fish richness in rural and urban areas of SEQ in response to climate change and/or urban growth. Whereas, when costs are considered, farm/land management with stream and riparian restoration are the most cost-effective strategies for macroinvertebrate and fish conservation. Our findings support riparian restoration as the most effective adaptation strategy to climate change and urban development, but because it is expensive it may often not be the most cost-efficient strategy. Our approach allows for these decisions to be evaluated explicitly. [ABSTRACT FROM AUTHOR]

Landscape dynamics pose substantial challenges to biodiversity conservation and could compromise the future effectiveness of protected areas (PAs). Multiple interacting drivers of landscape dynamics, including land-cover change, wildfire, and climate change, are usually studied separately. This limits our ability to respond effectively to conservation needs through appropriate measures. Using Catalonia (North-east Spain) as a case study, we evaluated the future representativeness of PAs in covering the distributions of bird species of conservation interest under the effects of different global change drivers and identified priority areas for their conservation in the future. We also evaluated the role of different global change drivers in defining future conservation needs. Under current management practices, land-cover change appears to be a more relevant driver than climate change. Forested habitats are predicted to increase at the expense of early successional habitats, and it appears that fires will not compensate for this loss by creating new early successional habitats. Consequently, early successional species are likely to suffer the greatest decline in distribution. Consequently, additional priority for future management should be given to the last available early successional habitats, mainly outside PAs, as their selection will be marginally driven by climate change or wildfires. The conservation of early successional habitats in the European Union can benefit from existing policies, particularly the 2030 Biodiversity Strategy or the Common Agriculture Policy. However, further evaluation is needed to explore whether these policies are suitable under dynamic landscape conditions or if new policy is needed to ensure effective conservation efforts. • The role of PAs is threatened by global change. • We assessed the future representativeness of PAs integrating global change drivers. • Early successional habitats outside PAs will have high future conservation value. • We identify future conservation needs to guide decision-making. • There are funding mechanisms into place to address future conservation needs. [ABSTRACT FROM AUTHOR]

Abstract: Urban climates are known to differ from those of the surrounding rural areas, as human activities in cities lead to changes in temperature, humidity and wind regimes. These changes can in turn affect the geographic distribution of species, the behaviour of animals and the phenology of plants. The grey-headed flying-fox (Pteropus poliocephalus) is a large, nomadic bat from eastern Australia that roosts in large colonies known as camps. Historically a warm temperate to tropical species, P. poliocephalus recently established a year-round camp in the Royal Botanic Gardens Melbourne. Using a bioclimatic analysis, we demonstrated that on the basis of long-term data, Melbourne does not fall within the climatic range of other P. poliocephalus camp sites in Australia. Melbourne is drier than other summer camps, and cooler and drier than other winter camps. The city also receives less radiation, in winter and annually, than the other summer and winter camps of P. poliocephalus. However, we found that temperatures in central Melbourne have been increasing since the 1950s, leading to warmer conditions and a reduction in the number of frosts. In addition, artificial watering of parks and gardens in the city may contribute the equivalent of 590mm (95% CI: 450–720mm) of extra rainfall per year. It appears that human activities have increased temperatures and effective precipitation in central Melbourne, creating a more suitable climate for camps of the grey-headed flying-fox. As demonstrated by this example, anthropogenic climate change is likely to complicate further the task of conserving biological diversity in urban environments. [Copyright &y& Elsevier]

There is a growing recognition that conservation strategies should be designed accounting for cross-realm connections, such as freshwater connections to land and sea, to ensure effectiveness of marine spatial protection and minimize perverse outcomes of changing land-use. Yet, examples of integration across realms are relatively scarce, with most targeting priorities in a single realm, such as marine or freshwater, while minimizing threats originating in terrestrial ecosystems. To date, no study has optimized priorities across multiple realms to produce a spatially explicit integrated conservation plan that simultaneously accounts for multiple human activities at a national scale. This represents a major gap in the application of existing cross-realm planning theory. We present a national scale conservation framework for selecting protected areas using a case study of Papua New Guinea (PNG) that integrates multiple systems and ecological connectivity to account for cross-realm benefits and minimize threats of land-use and climate change. The relative importance of both the forests and inshore reef environments to PNG subsistence and commercial livelihoods emphasizes the importance of considering the connections between the land and sea. The plan was commissioned by the PNG Conservation and Environment Protection Authority and identifies a comprehensive set of priorities that meet conservation targets in both the land and sea. Our national-scale prioritization framework is useful for agencies and managers looking to implement actions given multiple objectives, including watershed management and biodiversity protection, and ensures actions are efficient and effective across the land and sea. [ABSTRACT FROM AUTHOR]

Stressors to marine ecosystems are increasing, driven by human activities in the sea and on land, and climate change. Cumulative impact maps highlight regions affected by multiple human activities, but efficient conservation investment requires linking dominant pressures to management actions that best address the particular drivers of impacts. We rebuild cumulative impact maps by stressor type (climate change, marine and land) at a global scale to evaluate the expected effectiveness of various management strategies for all coastal territories. Average cumulative impact from non-marine stressors (climate and land) was double those of marine impacts at a national level. The greatest climate impacts by country were in the waters of Pacific Island and Antarctic territories; in the Caspian Sea region and East-Asia for land impacts; and in the waters of European, East-Asian and Caribbean countries for marine impacts. We developed a conservation-effectiveness indicator for the 10 worst-impacted countries in each of the three stressor categories. The indicator considered common management tools for each stressor category: ecosystem-based adaptation and disaster risk reduction (climate), marine protected areas (marine) and integrated coastal management (land). Key disparities were found between broad-scale management of marine ecosystems and the dominant stressors, with existing management in tropical island nations likely insufficient to address intense impacts from climate change. These countries also typically had low performance on governance indicators, suggesting challenges in implementing new mitigation. We highlight trade-offs in making decisions for stressor mitigation and offer strategic guidance on identifying locations to target management of marine, land, or climate impacts. [ABSTRACT FROM AUTHOR]