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Chen X, Evans TG, Jeschke JM, Jähnig SC, He F. Global introductions and environmental impacts of freshwater megafish. GLOBAL CHANGE BIOLOGY 2024; 30:e17289. [PMID: 38660818 DOI: 10.1111/gcb.17289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 03/28/2024] [Accepted: 04/06/2024] [Indexed: 04/26/2024]
Abstract
Freshwater megafish species, such as sturgeons, salmonids, carps, and catfishes, have a maximum reported weight ≥30 kg. Due to their charisma and economic value, they have been widely introduced outside of their native ranges. Here, we provide a comprehensive overview of the introduction of freshwater megafish and an assessment of their environmental impacts. Of the 134 extant freshwater megafish species, 46% have been introduced to new environments, and of these, 69% have established self-sustaining alien populations. These introductions affect 59% of the world's main basins, with the USA and western Europe being particular hotspots of megafish introductions. The common carp (Cyprinus carpio) is the most widely introduced species. Using the Environmental Impact Classification for Alien Taxa (EICAT and EICAT+) frameworks, we assessed the severity and type of negative and positive impacts posed by alien megafish on native species. Alien megafish caused negative impacts through nine different mechanisms, with predation being the most frequently reported mechanism, followed by herbivory and competition. Moreover, 58% of the alien megafish species with sufficient data to evaluate the severity of their impacts caused declining populations of native species, or worse, extirpations of native species populations. The positive environmental impacts of alien megafish were far less frequently documented. They include biotic interactions that benefit native species, and the provision of trophic resources or habitats. Widely introduced or extensively studied species are more likely to have documented severe impacts on native species. There is a clear trade-off between the economic benefits associated with megafish introductions and the severe adverse impacts they have on native biodiversity. Our study highlights the need for comprehensive risk assessments to evaluate the potential environmental impacts of megafish. More research and long-term monitoring schemes are required to inform management actions to protect biodiversity, particularly in the Global South.
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Affiliation(s)
- Xing Chen
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
| | - Thomas G Evans
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
| | - Jonathan M Jeschke
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
| | - Sonja C Jähnig
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Geography Department, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Fengzhi He
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Geography Department, Humboldt-Universität zu Berlin, Berlin, Germany
- State Key Laboratory of Black Soils Conservation and Utilization, Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, China
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He F, Svenning JC, Chen X, Tockner K, Kuemmerle T, le Roux E, Moleón M, Gessner J, Jähnig SC. Freshwater megafauna shape ecosystems and facilitate restoration. Biol Rev Camb Philos Soc 2024. [PMID: 38411930 DOI: 10.1111/brv.13062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 01/31/2024] [Accepted: 02/02/2024] [Indexed: 02/28/2024]
Abstract
Freshwater megafauna, such as sturgeons, giant catfishes, river dolphins, hippopotami, crocodylians, large turtles, and giant salamanders, have experienced severe population declines and range contractions worldwide. Although there is an increasing number of studies investigating the causes of megafauna losses in fresh waters, little attention has been paid to synthesising the impacts of megafauna on the abiotic environment and other organisms in freshwater ecosystems, and hence the consequences of losing these species. This limited understanding may impede the development of policies and actions for their conservation and restoration. In this review, we synthesise how megafauna shape ecological processes in freshwater ecosystems and discuss their potential for enhancing ecosystem restoration. Through activities such as movement, burrowing, and dam and nest building, megafauna have a profound influence on the extent of water bodies, flow dynamics, and the physical structure of shorelines and substrata, increasing habitat heterogeneity. They enhance nutrient cycling within fresh waters, and cross-ecosystem flows of material, through foraging and reproduction activities. Freshwater megafauna are highly connected to other freshwater organisms via direct consumption of species at different trophic levels, indirect trophic cascades, and through their influence on habitat structure. The literature documenting the ecological impacts of freshwater megafauna is not evenly distributed among species, regions, and types of ecological impacts, with a lack of quantitative evidence for large fish, crocodylians, and turtles in the Global South and their impacts on nutrient flows and food-web structure. In addition, population decline, range contraction, and the loss of large individuals have reduced the extent and magnitude of megafaunal impacts in freshwater ecosystems, rendering a posteriori evaluation more difficult. We propose that reinstating freshwater megafauna populations holds the potential for restoring key ecological processes such as disturbances, trophic cascades, and species dispersal, which will, in turn, promote overall biodiversity and enhance nature's contributions to people. Challenges for restoration actions include the shifting baseline syndrome, potential human-megafauna competition for habitats and resources, damage to property, and risk to human life. The current lack of historical baselines for natural distributions and population sizes of freshwater megafauna, their life history, trophic interactions with other freshwater species, and interactions with humans necessitates further investigation. Addressing these knowledge gaps will improve our understanding of the ecological roles of freshwater megafauna and support their full potential for facilitating the development of effective conservation and restoration strategies to achieve the coexistence of humans and megafauna.
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Affiliation(s)
- Fengzhi He
- Key Laboratory of Wetland Ecology and Environment, State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Shengbei Street 4888, Changchun, 130102, China
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
- Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin, 10099, Germany
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Ny Munkegade 114, Aarhus, 8000, Denmark
| | - Jens-Christian Svenning
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Ny Munkegade 114, Aarhus, 8000, Denmark
| | - Xing Chen
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
- Institute of Biology, Freie Universität Berlin, Königin-Luise-Str. 1-3, Berlin, 14195, Germany
| | - Klement Tockner
- Senckenberg Society for Nature Research, Senckenberganlage 25, Frankfurt am Main, 60325, Germany
- Faculty for Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Straße 9, Frankfurt am Main, 60438, Germany
| | - Tobias Kuemmerle
- Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin, 10099, Germany
| | - Elizabeth le Roux
- Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) and Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Ny Munkegade 114, Aarhus, 8000, Denmark
| | - Marcos Moleón
- Department of Zoology, University of Granada, Avenida de Fuente Nueva S/N, Granada, 18071, Spain
| | - Jörn Gessner
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
| | - Sonja C Jähnig
- Leibniz Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
- Geography Department, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin, 10099, Germany
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3
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Canning AD, Death RG. Establishing riverine nutrient criteria using individual taxa thresholds. WATER RESEARCH 2023; 246:120731. [PMID: 37844342 DOI: 10.1016/j.watres.2023.120731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 09/29/2023] [Accepted: 10/10/2023] [Indexed: 10/18/2023]
Abstract
Nutrient enrichment is one of the most pervasive impacts on aquatic ecosystems globally. Approaches to establish nutrient criteria that safeguard aquatic ecosystem health are highly variable and, in many instances, criteria are derived from correlations between in-situ nutrient concentrations and biological indices. Summarising entire assemblages with a single index can result in a substantial loss of information and potentially weaker relationships. In this study, we compared the derivation of nutrient criteria using biological indices and those from individual taxa for rivers and streams in New Zealand. Random forest models, including nutrient concentrations, were built to predict two biological indices and individual taxa across New Zealand's river monitoring network. For all acceptable models, the response of the biological indices and individual taxa to increasing Dissolved Inorganic Nitrogen (DIN) and Dissolved Reactive Phosphorus (DRP) were then predicted for every river reach across the nation, and nutrient concentrations that protected 80% of taxa were then identified. Models for the biological indices were poor but were good for most of the taxa, with nutrient concentrations almost always being the most influential factor. To ensure persistence of at least 80% of the taxa within a river reach, we estimated that DIN (Dissolved Inorganic Nitrogen) concentrations would need to be below 0.57-1.32 mg/L, and DRP (Dissolved Reactive Phosphorus) concentrations below 0.019-0.033 mg/L, depending on the river type. In general, high order, low slope rivers and streams required more stringent nutrient criteria than steep, low order streams. The link between nutrient concentrations and biological indices were weak and likely suffer from the loss of information from summarising an entire assemblage into a single numeric. We consider that the derivation of nutrient criteria for waterways should also examine the individual relationships with the taxa in a river system to establish protection for a desired proportion of taxa.
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Affiliation(s)
- A D Canning
- Centre for Tropical Water and Aquatic Ecosystem Research (TropWATER), James Cook University, 1 James Cook Drive, Townsville 4811, Australia; Faculty of Science and Engineering, Southern Cross University, 1 Military Drive, Lismore 2480, Australia.
| | - R G Death
- School of Natural Sciences, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand
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Sen S, Thomas S, Joe Kizhakudan S, Dash G, Pradhan RK, Ghosh S, Das M, Dash B, Zacharia PU. New observations of the endangered giant freshwater whipray, Urogymnus polylepis, provide further evidence for its distribution and breeding in the north-east coast of India. JOURNAL OF FISH BIOLOGY 2022; 101:1611-1616. [PMID: 36151886 DOI: 10.1111/jfb.15223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 09/18/2022] [Indexed: 06/16/2023]
Abstract
The present study reports observations of 13 giant freshwater whipray (Urogymnus polylepis) from commercial fish landings along the north-east coast of India and updates existing records based on field observations and local social media reports. The disc width of the landed specimens ranged from 120 to 223 cm and they weighed 95-300 kg. All 13 specimens observed were mature (nine females and four males) and three females were pregnant, with embryo numbers ranging between 4 and 15. Globally, U. polylepis is listed as 'Endangered', and greater protection measures are needed in India to assist in reversing current population declines.
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Affiliation(s)
- Swatipriyanka Sen
- Finfish and Shellfish Fisheries Division, Puri Field Centre of ICAR-Central Marine Fisheries Research Institute, Puri, India
| | - Sujitha Thomas
- Finfish Fisheries Division, Mangalore Regional centre of ICAR-Central Marine Fisheries Research Institute, Mangalore, India
| | - Shoba Joe Kizhakudan
- Finfish Fisheries Division, Madras Regional Station of ICAR-Central Marine Fisheries Research Institute, Chennai, India
| | - Gyanaranjan Dash
- Finfish and Shellfish Fisheries Division, Puri Field Centre of ICAR-Central Marine Fisheries Research Institute, Puri, India
| | - Rajesh Kumar Pradhan
- Finfish and Shellfish Fisheries Division, Puri Field Centre of ICAR-Central Marine Fisheries Research Institute, Puri, India
| | - Shubhadeep Ghosh
- Finfish Fisheries Division, Visakhapatnam Regional Centre of ICAR-Central Marine Fisheries Research Institute, Visakhapatnam, India
| | - Madhumita Das
- Finfish and Shellfish Fisheries Division, Puri Field Centre of ICAR-Central Marine Fisheries Research Institute, Puri, India
| | - Biswajit Dash
- Finfish and Shellfish Fisheries Division, Puri Field Centre of ICAR-Central Marine Fisheries Research Institute, Puri, India
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5
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Jeremias G, Veloso T, Gonçalves FJM, Van Nieuwerburgh F, Pereira JL, Asselman J. Multigenerational DNA methylation responses to copper exposure in Daphnia: Potential targets for epigenetic biomarkers? CHEMOSPHERE 2022; 308:136231. [PMID: 36055596 DOI: 10.1016/j.chemosphere.2022.136231] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/23/2022] [Accepted: 08/24/2022] [Indexed: 06/15/2023]
Abstract
Epigenetic mechanisms are moving to the forefront of environmental sciences, as environmentally induced epigenetic changes shape biological responses to chemical contamination. This work focused on Daphnia as a representative of potentially threatened freshwater biota, aiming to gain an insight into the involvement of epigenetic mechanisms in their response and eventual adaptation to metal contamination. Copper-induced DNA methylation changes, their potential transgenerational inheritance, and life-history traits were assessed. Organisms with different histories of past exposure to copper were exposed to toxic levels of the element for one generation (F0) and then monitored for three subsequent unexposed generations (F1, F2, and F3). Overall, methylation changes targeted important genes for counteracting the effects of metals and oxidative stress, including dynein light chain, ribosomal kinase and nuclear fragile X mental retardation-interacting protein. Also, contrasting overall and gene-specific methylation responses were observed in organisms differing in their history of exposure to copper, with different transgenerational methylation responses being also identified among the two groups, without apparent life-history costs. Taken together, these results demonstrate the capacity of copper to promote epigenetic transgenerational inheritance in a manner related explicitly to history of exposure, thereby supporting the development and incorporation of epigenetic biomarkers in risk assessment frameworks.
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Affiliation(s)
- Guilherme Jeremias
- Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Portugal
| | - Telma Veloso
- Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Portugal; CICECO - Aveiro Institute of Materials & Department of Chemistry, University of Aveiro, Portugal
| | - Fernando J M Gonçalves
- Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Portugal
| | | | - Joana Luísa Pereira
- Department of Biology & CESAM - Centre for Environmental and Marine Studies, University of Aveiro, Portugal.
| | - Jana Asselman
- Blue Growth Research Lab, Ghent University, Bluebridge Building, Ostend Science Park 1, 8400, Ostend, Belgium
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Abraham AJ, Roman J, Doughty CE. The sixth R: Revitalizing the natural phosphorus pump. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 832:155023. [PMID: 35390369 DOI: 10.1016/j.scitotenv.2022.155023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
Phosphorus (P) is essential for all life on Earth and sustains food production. Yet, the easily accessible deposits of phosphate-rich rock, which underpin the green revolution are becoming rarer. Here we propose a mechanism to help alleviate the problem of "peak phosphorus". In the past, wild animals played a large role in returning P from ocean depths back to the continental interiors. In doing so, they collectively retained and redistributed P within the biosphere, supporting a more fertile planet. However, species extinctions and population reductions have reduced animal-mediated P transport >90% over the past 12,000 years. Recently a 5R strategy was developed to Realign P inputs, Reduce P losses, Recycle P in bio-resources, Recover P in wastes, and Redefine P in food systems. Here, we suggest a sixth R, to Revitalize the Natural Phosphorus Pump (RNPP). Countries are starting to mandate P recycling and we propose a P-trading scheme based on REDD+, where a country could partially achieve its recycling goals by restoring past animal-mediated P pathways. Accrued money from this scheme could be used to restore or conserve wild animal populations, while increasing natural P recycling.
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Affiliation(s)
- Andrew J Abraham
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University Flagstaff, AZ 86011, USA.
| | - Joe Roman
- Gund Institute for Environment, Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, VT 05445, USA
| | - Christopher E Doughty
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University Flagstaff, AZ 86011, USA
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Ingeman KE, Zhao LZ, Wolf C, Williams DR, Ritger AL, Ripple WJ, Kopecky KL, Dillon EM, DiFiore BP, Curtis JS, Csik SR, Bui A, Stier AC. Glimmers of hope in large carnivore recoveries. Sci Rep 2022; 12:10005. [PMID: 35864129 PMCID: PMC9304400 DOI: 10.1038/s41598-022-13671-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 05/05/2022] [Indexed: 11/09/2022] Open
Abstract
In the face of an accelerating extinction crisis, scientists must draw insights from successful conservation interventions to uncover promising strategies for reversing broader declines. Here, we synthesize cases of recovery from a list of 362 species of large carnivores, ecologically important species that function as terminal consumers in many ecological contexts. Large carnivores represent critical conservation targets that have experienced historical declines as a result of direct exploitation and habitat loss. We examine taxonomic and geographic variation in current extinction risk and recovery indices, identify conservation actions associated with positive outcomes, and reveal anthropogenic threats linked to ongoing declines. We find that fewer than 10% of global large carnivore populations are increasing, and only 12 species (3.3%) have experienced genuine improvement in extinction risk, mostly limited to recoveries among marine mammals. Recovery is associated with species legislation enacted at national and international levels, and with management of direct exploitation. Conversely, ongoing declines are robustly linked to threats that include habitat modification and human conflict. Applying lessons from cases of large carnivore recovery will be crucial for restoring intact ecosystems and maintaining the services they provide to humans.
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Affiliation(s)
- Kurt E Ingeman
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA. .,David H. Smith Conservation Research Program, Society for Conservation Biology, Washington, DC, USA.
| | - Lily Z Zhao
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - Christopher Wolf
- Global Trophic Cascades Program, Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
| | - David R Williams
- School of Earth and Environment, University of Leeds, Leeds, UK.,Bren School of Environmental Science and Management, University of California, Santa Barbara, CA, USA
| | - Amelia L Ritger
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - William J Ripple
- Global Trophic Cascades Program, Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
| | - Kai L Kopecky
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - Erin M Dillon
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - Bartholomew P DiFiore
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - Joseph S Curtis
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - Samantha R Csik
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - An Bui
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA
| | - Adrian C Stier
- Department of Ecology, Evolution, and Marine Biology, University of California, 2018 Noble Hall, Santa Barbara, CA, 93106, USA.
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Sanchez EGS, Delocado ED, Freitag H. Two new species of Anacaena Thomson, 1859 (Coleoptera, Hydrophilidae) from Northern Luzon, Philippines. Zookeys 2022; 1112:11-25. [PMID: 36760626 PMCID: PMC9848642 DOI: 10.3897/zookeys.1112.85752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 06/01/2022] [Indexed: 11/12/2022] Open
Abstract
Two species of Anacaena Thomson, 1859, A.angatbuhay sp. nov. and A.auxilium sp. nov., are described from Northern Luzon, Philippines. The new species can be distinguished through colour, body shape, surface puncturation and characteristic aedeagi. Descriptions are provided and complemented with habitus photographs and drawings of the aedeagi. Data on genus distribution in the Philippines are reviewed and an updated Philippine checklist is provided.
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Affiliation(s)
- Enrico Gerard S. Sanchez
- Ateneo Biodiversity Research Laboratory, Department of Biology, School of Science and Engineering, Ateneo de Manila University, Quezon City, 1108 PhilippinesAteneo de Manila UniversityQuezon CityPhilippines
| | - Emmanuel D. Delocado
- Ateneo Biodiversity Research Laboratory, Department of Biology, School of Science and Engineering, Ateneo de Manila University, Quezon City, 1108 PhilippinesAteneo de Manila UniversityQuezon CityPhilippines
| | - Hendrik Freitag
- Ateneo Biodiversity Research Laboratory, Department of Biology, School of Science and Engineering, Ateneo de Manila University, Quezon City, 1108 PhilippinesAteneo de Manila UniversityQuezon CityPhilippines
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Schols R, Carolus H, Hammoud C, Muzarabani KC, Barson M, Huyse T. Invasive snails, parasite spillback, and potential parasite spillover drive parasitic diseases of Hippopotamus amphibius in artificial lakes of Zimbabwe. BMC Biol 2021; 19:160. [PMID: 34412627 PMCID: PMC8377832 DOI: 10.1186/s12915-021-01093-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 07/12/2021] [Indexed: 11/25/2022] Open
Abstract
Background Humans impose a significant pressure on large herbivore populations, such as hippopotami, through hunting, poaching, and habitat destruction. Anthropogenic pressures can also occur indirectly, such as artificial lake creation and the subsequent introduction of invasive species that alter the ecosystem. These events can lead to drastic changes in parasite diversity and transmission, but generally receive little scientific attention. Results In order to document and identify trematode parasites of the common hippopotamus (Hippopotamus amphibius) in artificial water systems of Zimbabwe, we applied an integrative taxonomic approach, combining molecular diagnostics and morphometrics on archived and new samples. In doing so, we provide DNA reference sequences of the hippopotamus liver fluke Fasciola nyanzae, enabling us to construct the first complete Fasciola phylogeny. We describe parasite spillback of F. nyanzae by the invasive freshwater snail Pseudosuccinea columella, as a consequence of a cascade of biological invasions in Lake Kariba, one of the biggest artificial lakes in the world. Additionally, we report an unknown stomach fluke of the hippopotamus transmitted by the non-endemic snail Radix aff. plicatula, an Asian snail species that has not been found in Africa before, and the stomach fluke Carmyerius cruciformis transmitted by the native snail Bulinus truncatus. Finally, Biomphalaria pfeifferi and two Bulinus species were found as new snail hosts for the poorly documented hippopotamus blood fluke Schistosoma edwardiense. Conclusions Our findings indicate that artificial lakes are breeding grounds for endemic and non-endemic snails that transmit trematode parasites of the common hippopotamus. This has important implications, as existing research links trematode parasite infections combined with other stressors to declining wild herbivore populations. Therefore, we argue that monitoring the anthropogenic impact on parasite transmission should become an integral part of wildlife conservation efforts. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01093-2.
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Affiliation(s)
- Ruben Schols
- Department of Biology, Royal Museum for Central Africa, Tervuren, Belgium. .,Laboratory of Aquatic Biology, KU Leuven Kulak, Kortrijk, Belgium.
| | - Hans Carolus
- Laboratory of Molecular Cell Biology, KU Leuven-VIB Center for Microbiology, Leuven, Belgium
| | - Cyril Hammoud
- Department of Biology, Royal Museum for Central Africa, Tervuren, Belgium.,Limnology Research Unit, Ghent University, Ghent, Belgium
| | | | - Maxwell Barson
- Department of Biological Sciences, University of Zimbabwe, Harare, Zimbabwe.,Department of Biological Sciences, University of Botswana, Gaborone, Botswana.,Lake Kariba Research Station, University of Zimbabwe, Kariba, Zimbabwe
| | - Tine Huyse
- Department of Biology, Royal Museum for Central Africa, Tervuren, Belgium
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10
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Paudel S, Koprowski JL, Thakuri U, Karki A. In-stream habitat availability for river dolphins in response to flow: Use of ecological integrity to manage river flows. PLoS One 2021; 16:e0241099. [PMID: 34288903 PMCID: PMC8294540 DOI: 10.1371/journal.pone.0241099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 07/03/2021] [Indexed: 11/19/2022] Open
Abstract
Population decline and extinction risk of river dolphins are primarily associated with flow alteration. Previous studies predominantly highlighted maintenance of adequate flow for low water seasons when habitats contract and the risk of local extinction escalates. Although river dolphins are sensitive to reduction in river flow, no studies quantify the relationships between flow and ecology of river dolphins to mitigate the potential adverse impacts of flow alteration. We quantify the relationships between flow and the ecology of river cetaceans concerning Ganges River dolphins (GRD; Platanista gangetica gangetica) usable area availability (AWS) for the low water season at wider flows (50-575 m3/s) at finer spatial and temporal scales. This study reveals that distribution of area usable to GRD is highly regulated by the adequate flow and river attributes (velocity and depth) interactions that likely offer energetically efficient modes of locomotion to GRD, suggesting the hydro-physical environment as a major determinant of river dolphin distribution and abundance. Flow and AWS relationships indicate that the flow during the dry season negatively contributed to AWS, whereas that of pre-monsoon maximized the AWS, suggesting that modifying flow regimes does alter in-stream habitats at varying spatial scales and may influence life-history strategies. Substantial fragmentation in suitable pool availability and loss of longitudinal connectivity exhibited by dry season flow suggested a higher risk of adverse biological effects during the dry season, which may reduce population viability by reducing survivorship and reproduction failure. Owing to river dolphins' dependence on the attribute of freshwater flow, they can be expected to be more affected by flow regulations as interactive effects. Considering the seasonal effects and changes in the availability of usable areas by flow alteration, adopting effective habitat retention plans by water-based development projects appears critical to avoid further ecological risks in aquatic species conservation. Identifying priority riverscapes for river cetaceans and prioritizing investment opportunities is an essential first step towards effective riverine cetacean conservation.
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Affiliation(s)
- Shambhu Paudel
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America
- Tribhuvan University, Institute of Forestry, Pokhara, Nepal
- * E-mail:
| | - John L. Koprowski
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America
- Haub School of Environment and Natural Resources, University of Wyoming, Bim Kendall House, Laramie, WY, United States of America
| | - Usha Thakuri
- Tribhuvan University, Institute of Forestry, Pokhara, Nepal
| | - Ajay Karki
- Ministry of Forests and Environment, Government of Nepal, Kathmandu, Nepal
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Abstract
Abstract
Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are seahorses (Hippocampus spp.: 14/42 species, with an additional 17 that are Data Deficient) or freshwater pipefishes of the genus Microphis (2/18 species, with seven additional that are Data Deficient). Two species are Near Threatened. Nearly one-third of syngnathiformes (97 species) are Data Deficient and could potentially be threatened, requiring further field research and evaluation. Most species (61%) were, however, evaluated as Least Concern. Primary threats to syngnathids are (1) overexploitation, primarily by non-selective fisheries, for which most assessments were determined by criterion A (Hippocampus) and/or (2) habitat loss and degradation, for which assessments were determined by criterion B (Microphis and some Hippocampus). Threatened species occurred in most regions but more are found in East and South-east Asia and in South African estuaries. Vital conservation action for syngnathids, including constraining fisheries, particularly non-selective extraction, and habitat protection and rehabilitation, will benefit many other aquatic species.
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He F, Langhans SD, Zarfl C, Wanke R, Tockner K, Jähnig SC. Combined effects of life-history traits and human impact on extinction risk of freshwater megafauna. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2021; 35:643-653. [PMID: 32671869 DOI: 10.1111/cobi.13590] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 06/16/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
Megafauna species are intrinsically vulnerable to human impact. Freshwater megafauna (i.e., freshwater animals ≥30 kg, including fishes, mammals, reptiles, and amphibians) are subject to intensive and increasing threats. Thirty-four species are listed as critically endangered on the International Union for Conservation of Nature (IUCN). Red List of Threatened Species, the assessments for which are an important basis for conservation actions but remain incomplete for 49 (24%) freshwater megafauna species. Consequently, the window of opportunity for protecting these species could be missed. Identifying the factors that predispose freshwater megafauna to extinction can help predict their extinction risk and facilitate more effective and proactive conservation actions. Thus, we collated 8 life-history traits for 206 freshwater megafauna species. We used generalized linear mixed models to examine the relationships between extinction risk based on the IUCN Red List categories and the combined effect of multiple traits, as well as the effect of human impact on these relationships for 157 classified species. The most parsimonious model included human impact and traits related to species' recovery potential including life span, age at maturity, and fecundity. Applying the most parsimonious model to 49 unclassified species predicted that 17 of them are threatened. Accounting for model predictions together with IUCN Red List assessments, 50% of all freshwater megafauna species are considered threatened. The Amazon and Yangtze basins emerged as global diversity hotspots of threatened freshwater megafauna, in addition to existing hotspots, including the Ganges-Brahmaputra and Mekong basins and the Caspian Sea region. Assessment and monitoring of those species predicted to be threatened are needed, especially in the Amazon and Yangtze basins. Investigation of life-history traits and trends in population and distribution, regulation of overexploitation, maintaining river connectivity, implementing protected areas focusing on freshwater ecosystems, and integrated basin management are required to protect threatened freshwater megafauna in diversity hotspots.
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Affiliation(s)
- Fengzhi He
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
- Institute of Biology, Freie Universität Berlin, Königin-Luise-Str. 1-3, Berlin, 14195, Germany
- School of Geography, Queen Mary University of London, London, E1 4NS, UK
| | - Simone D Langhans
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
- Department of Zoology, University of Otago, P.O. Box 56, Dunedin, 9054, New Zealand
- BC3 - Basque Centre for Climate Change, Sede Building 1, Leioa, 48904, Spain
| | - Christiane Zarfl
- Center for Applied Geosciences, Eberhard Karls Universität Tübingen, Hölderlinstr. 12, Tübingen, 72074, Germany
| | - Roland Wanke
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
- Institute of Biology, Freie Universität Berlin, Königin-Luise-Str. 1-3, Berlin, 14195, Germany
| | - Klement Tockner
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
- Institute of Biology, Freie Universität Berlin, Königin-Luise-Str. 1-3, Berlin, 14195, Germany
- Austrian Science Fund (FWF), Sensengasse 1, Vienna, 1090, Austria
| | - Sonja C Jähnig
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, Berlin, 12587, Germany
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Integrated Impact Assessment for Sustainable Hydropower Planning in the Vjosa Catchment (Greece, Albania). SUSTAINABILITY 2021. [DOI: 10.3390/su13031514] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mitigating climate change, while human population and economy are growing globally, requires a bold shift to renewable energy sources. Among renewables, hydropower is currently the most economic and efficient technique. However, due to a lack of impact assessments at the catchment scale in the planning process, the construction of hydropower plants (HPP) may have unexpected ecological, socioeconomic, and political ramifications in the short and in the long term. The Vjosa River, draining parts of Northern Greece and Albania, is one of the few predominantly free-flowing rivers left in Europe; at the same time its catchment is identified an important resource for future hydropower development. While current hydropower plants are located along tributaries, planned HPP would highly impact the free-flowing main stem. Taking the Vjosa catchment as a case study, the aim of this study was to develop a transferable impact assessment that ranks potential hydropower sites according to their projected impacts on a catchment scale. Therefore, we integrated established ecological, social, and economic indicators for all HPP planned in the river catchment, while considering their capacity, and developed a ranking method based on impact categories. For the Vjosa catchment, ten hydropower sites were ranked as very harmful to the environment as well as to society. A sensitivity analysis revealed that this ranking is dependent upon the selection of indicators. Small HPP showed higher cumulative impacts than large HPP, when normalized to capacity. This study empowers decision-makers to compare both the ranked impacts and the generated energy of planned dam projects at the catchment scale.
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Sifundza DS, Chakona A, Kadye WT. Distribution patterns and habitat associations of Sandelia bainsii (Teleostei: Anabantidae), a highly threatened narrow-range endemic freshwater fish. JOURNAL OF FISH BIOLOGY 2021; 98:292-303. [PMID: 33030223 DOI: 10.1111/jfb.14580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/23/2020] [Accepted: 10/05/2020] [Indexed: 06/11/2023]
Abstract
Sandelia bainsii is a range-restricted and highly threatened freshwater fish endemic to South Africa. Recent genetic evidence suggests that this species comprises three allopatrically distributed lineages that have been informally designated as Sandelia sp. "Kowie," Sandelia sp. "Keiskamma" and Sandelia sp. "Buffalo." As these lineages have only been recently identified and are likely to face a high risk of extinction because of restricted distributions, there is a critical need for generating ecological information to guide conservation prioritisation. The present study compared the historical and current distribution patterns, together with the habitat associations of Sandelia sp. "Kowie" in the Koonap and Kat rivers, tributaries of the Great Fish River. This study indicated that this lineage has been extirpated from one of the three localities in the Koonap River where it was historically abundant. In the Kat River, the current distribution of Sandelia sp. "Kowie" was comparable to its historical range, but its future persistence is threatened by the presence of non-native piscivores, instream physical barriers and potential future exploration for shale gas and infrastructure development in the Karoo Basin. A generalised hurdle negative binomial model revealed that although this lineage's probability of occurrence was high in habitats with boulder and sand substrates, and low conductivity, habitat characteristics were poor predictors of its abundance. Thus, it was postulated that the current range of this lineage probably represents the only available habitats for the persistence of different life stages for this taxon. Alternatively, the observed patterns may suggest the possibility of a shift in habitat associations, possibly for optimum utilisation of the remaining refugia within this river system. Immediate conservation measures should focus on preventing the spread on non-native invasive fishes, whereas future studies should evaluate the impacts of population fragmentation and identify appropriate intervention measures to maintain this lineage's long-term adaptive potential.
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Affiliation(s)
- Delsy S Sifundza
- South African Institute for Aquatic Biodiversity, Grahamstown/Makhanda, South Africa
- Department of Ichthyology and Fisheries Science, Rhodes University, Grahamstown/Makhanda, South Africa
| | - Albert Chakona
- South African Institute for Aquatic Biodiversity, Grahamstown/Makhanda, South Africa
- Department of Ichthyology and Fisheries Science, Rhodes University, Grahamstown/Makhanda, South Africa
| | - Wilbert T Kadye
- Department of Ichthyology and Fisheries Science, Rhodes University, Grahamstown/Makhanda, South Africa
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15
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Albert JS, Destouni G, Duke-Sylvester SM, Magurran AE, Oberdorff T, Reis RE, Winemiller KO, Ripple WJ. Scientists' warning to humanity on the freshwater biodiversity crisis. AMBIO 2021; 50:85-94. [PMID: 32040746 PMCID: PMC7708569 DOI: 10.1007/s13280-020-01318-8] [Citation(s) in RCA: 151] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/09/2019] [Accepted: 01/07/2020] [Indexed: 05/20/2023]
Abstract
Freshwater ecosystems provide irreplaceable services for both nature and society. The quality and quantity of freshwater affect biogeochemical processes and ecological dynamics that determine biodiversity, ecosystem productivity, and human health and welfare at local, regional and global scales. Freshwater ecosystems and their associated riparian habitats are amongst the most biologically diverse on Earth, and have inestimable economic, health, cultural, scientific and educational values. Yet human impacts to lakes, rivers, streams, wetlands and groundwater are dramatically reducing biodiversity and robbing critical natural resources and services from current and future generations. Freshwater biodiversity is declining rapidly on every continent and in every major river basin on Earth, and this degradation is occurring more rapidly than in terrestrial ecosystems. Currently, about one third of all global freshwater discharges pass through human agricultural, industrial or urban infrastructure. About one fifth of the Earth's arable land is now already equipped for irrigation, including all the most productive lands, and this proportion is projected to surpass one third by midcentury to feed the rapidly expanding populations of humans and commensal species, especially poultry and ruminant livestock. Less than one fifth of the world's preindustrial freshwater wetlands remain, and this proportion is projected to decline to under one tenth by midcentury, with imminent threats from water transfer megaprojects in Brazil and India, and coastal wetland drainage megaprojects in China. The Living Planet Index for freshwater vertebrate populations has declined to just one third that of 1970, and is projected to sink below one fifth by midcentury. A linear model of global economic expansion yields the chilling prediction that human utilization of critical freshwater resources will approach one half of the Earth's total capacity by midcentury. Although the magnitude and growth of the human freshwater footprint are greater than is generally understood by policy makers, the news media, or the general public, slowing and reversing dramatic losses of freshwater species and ecosystems is still possible. We recommend a set of urgent policy actions that promote clean water, conserve watershed services, and restore freshwater ecosystems and their vital services. Effective management of freshwater resources and ecosystems must be ranked amongst humanity's highest priorities.
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Affiliation(s)
- James S. Albert
- Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70503 USA
| | - Georgia Destouni
- Department of Physical Geography, Bolin Centre for Climate Research, Stockholm University, 106 91 Stockholm, Sweden
| | | | - Anne E. Magurran
- Centre for Biological Diversity, University of St Andrews, St Andrews, KY16 UK
| | - Thierry Oberdorff
- UMR5174 EDB (Laboratoire Evolution et Diversité Biologique), CNRS, IRD, UPS, Université Paul Sabatier, 31062 Toulouse, France
| | - Roberto E. Reis
- Department of Biodiversity and Ecology, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS 90619-900 Brazil
| | - Kirk O. Winemiller
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX 77843 USA
| | - William J. Ripple
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97330 USA
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16
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Smith GR, Rettig JE, Iverson JB. Frequency of and Temporal Trends in Shell Anomalies in a Turtle Community in a Northern Indiana Lake. CHELONIAN CONSERVATION AND BIOLOGY 2020. [DOI: 10.2744/ccb-1408.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Geoffrey R. Smith
- Department of Biology, Denison University, Granville, Ohio 43023 USA [, ]
| | - Jessica E. Rettig
- Department of Biology, Denison University, Granville, Ohio 43023 USA [, ]
| | - John B. Iverson
- Department of Biology, Earlham College, Richmond, Indiana 47374 USA []
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17
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Fulfilling Nature Needs Half through terrestrial-focused protected areas and their adequacy for freshwater ecosystems and biodiversity protection: A case from Bhutan. J Nat Conserv 2020. [DOI: 10.1016/j.jnc.2020.125894] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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18
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Zhang C, Zhu R, Sui X, Chen K, Li B, Chen Y. Ecological use of vertebrate surrogate species in ecosystem conservation. Glob Ecol Conserv 2020. [DOI: 10.1016/j.gecco.2020.e01344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Abstract
Megafishes are important to people and ecosystems worldwide. These fishes attain a maximum body weight of ≥30 kg. Global population declines highlight the need for more information about megafishes’ conservation status to inform management and conservation. The northern Cambodian Mekong River and its major tributaries are considered one of the last refugia for Mekong megafishes. We collected data on population abundance and body size trends for eight megafishes in this region to better understand their conservation statuses. Data were collected in June 2018 using a local ecological knowledge survey of 96 fishers in 12 villages. Fishers reported that, over 20 years, most megafishes changed from common to uncommon, rare, or locally extirpated. The most common and rarest species had mean last capture dates of 4.5 and 95 months before the survey, respectively. All species had declined greatly in body size. Maximum body weights reported by fishers ranged from 11–88% of their recorded maxima. Fishers identified 10 threats to megafishes, seven of which were types of illegal fishing. Electrofishing was the most prevalent. Results confirm that Mekong megafishes are severely endangered. Species Conservation Strategies should be developed and must address pervasive illegal fishing activities, alongside habitat degradation and blocked migrations, to recover declining populations.
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20
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Crookes S, Heer T, Castañeda RA, Mandrak NE, Heath DD, Weyl OLF, MacIsaac HJ, Foxcroft LC. Monitoring the silver carp invasion in Africa: a case study using environmental DNA (eDNA) in dangerous watersheds. NEOBIOTA 2020. [DOI: 10.3897/neobiota.56.47475] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Biodiverse habitats are increasingly subject to an intensification of anthropogenic stressors that may severely diminish species richness. Invasive species pose a dominant threat to biodiversity and biosecurity, particularly in biodiversity hotspots like Kruger National Park, South Africa. The invasive silver carp, Hypophthalmichthys molitrix, was introduced into the Olifants River and may experience range spread owing to favorable environmental conditions. Intensive monitoring protocols are necessary to effectively manage invasions of species like silver carp. Unfortunately, tropical and sub-tropical aquatic systems are difficult to monitor using conventional methods (e.g., netting, electrofishing and snorkeling) owing to a range of factors including the presence of dangerous megafauna. Conservation of such systems may be advanced by the adoption of novel methods, including environmental DNA (eDNA) detection. Here, we explore the utility of environmental DNA (eDNA) to conduct safe, reliable and repeatable surveys in dangerous watersheds using silver carp as a case study. We conducted eDNA surveys at 12 sites in two neighbouring watersheds, and determined that the species has expanded its range within the Olifants River and to the south in the Sabie River. Expansion in the former is consistent with the presence of suitable spawning conditions. We discuss the implications of this survey for biodiversity monitoring in similar aquatic systems in the tropics and advocate an integrative approach to biomonitoring in these ecosystems.
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21
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Moleón M, Sánchez-Zapata JA, Donázar JA, Revilla E, Martín-López B, Gutiérrez-Cánovas C, Getz WM, Morales-Reyes Z, Campos-Arceiz A, Crowder LB, Galetti M, González-Suárez M, He F, Jordano P, Lewison R, Naidoo R, Owen-Smith N, Selva N, Svenning JC, Tella JL, Zarfl C, Jähnig SC, Hayward MW, Faurby S, García N, Barnosky AD, Tockner K. Rethinking megafauna. Proc Biol Sci 2020; 287:20192643. [PMID: 32126954 DOI: 10.1098/rspb.2019.2643] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Concern for megafauna is increasing among scientists and non-scientists. Many studies have emphasized that megafauna play prominent ecological roles and provide important ecosystem services to humanity. But, what precisely are 'megafauna'? Here, we critically assess the concept of megafauna and propose a goal-oriented framework for megafaunal research. First, we review definitions of megafauna and analyse associated terminology in the scientific literature. Second, we conduct a survey among ecologists and palaeontologists to assess the species traits used to identify and define megafauna. Our review indicates that definitions are highly dependent on the study ecosystem and research question, and primarily rely on ad hoc size-related criteria. Our survey suggests that body size is crucial, but not necessarily sufficient, for addressing the different applications of the term megafauna. Thus, after discussing the pros and cons of existing definitions, we propose an additional approach by defining two function-oriented megafaunal concepts: 'keystone megafauna' and 'functional megafauna', with its variant 'apex megafauna'. Assessing megafauna from a functional perspective could challenge the perception that there may not be a unifying definition of megafauna that can be applied to all eco-evolutionary narratives. In addition, using functional definitions of megafauna could be especially conducive to cross-disciplinary understanding and cooperation, improvement of conservation policy and practice, and strengthening of public perception. As megafaunal research advances, we encourage scientists to unambiguously define how they use the term 'megafauna' and to present the logic underpinning their definition.
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Affiliation(s)
- Marcos Moleón
- Department of Conservation Biology, Doñana Biological Station-CSIC, Seville, Spain.,Department of Zoology, University of Granada, Granada, Spain
| | | | - José A Donázar
- Department of Conservation Biology, Doñana Biological Station-CSIC, Seville, Spain
| | - Eloy Revilla
- Department of Conservation Biology, Doñana Biological Station-CSIC, Seville, Spain
| | | | - Cayetano Gutiérrez-Cánovas
- FEHM-Lab-IRBIO, Department of Evolutionary Biology, Ecology and Environmental Sciences, University of Barcelona, Barcelona, Spain
| | - Wayne M Getz
- Department of ESPM, UC Berkeley, Berkeley, CA, USA.,School of Mathematical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | | | - Ahimsa Campos-Arceiz
- School of Environmental and Geographical Sciences, University of Nottingham Malaysia, Selangor, Malaysia.,Mindset Interdisciplinary Centre for Environmental Studies, University of Nottingham Malaysia, Selangor, Malaysia
| | - Larry B Crowder
- Hopkins Marine Station, Stanford University, Standford, CA, USA
| | - Mauro Galetti
- Departamento de Ecologia, Instituto de Biociências, Universidade Estadual Paulista, Rio Claro, SP, Brazil.,Department of Biology, University of Miami, Coral Gables, FL, USA
| | - Manuela González-Suárez
- Ecology and Evolutionary Biology Division, School of Biological Sciences, University of Reading, Reading, UK
| | - Fengzhi He
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany.,Institute of Biology, Freie Universität Berlin, Berlin, Germany
| | - Pedro Jordano
- Department of Conservation Biology, Doñana Biological Station-CSIC, Seville, Spain
| | - Rebecca Lewison
- Department of Biology, San Diego State University, San Diego, CA, USA
| | | | - Norman Owen-Smith
- School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Nuria Selva
- Institute of Nature Conservation, Polish Academy of Sciences, Kraków, Poland
| | - Jens-Christian Svenning
- Section for Ecoinformatics and Biodiversity, Department of Bioscience, Aarhus University, Aarhus C, Denmark.,Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Bioscience, Aarhus C, Denmark
| | - José L Tella
- Department of Conservation Biology, Doñana Biological Station-CSIC, Seville, Spain
| | - Christiane Zarfl
- Center for Applied Geoscience, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Sonja C Jähnig
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany
| | - Matt W Hayward
- College of Natural Sciences, Bangor University, Bangor, UK.,Centre for Wildlife Management, University of Pretoria, Pretoria, South Africa.,Centre for African Conservation Ecology, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa.,School of Environmental and Life Sciences, University of Newcastle, Newcastle, Australia
| | - Søren Faurby
- Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden.,Gothenburg Global Biodiversity Centre, Göteborg, Sweden
| | - Nuria García
- Department of Geodynamics, Stratigraphy and Paleontology, Quaternary Ecosystems, University Complutense of Madrid, Madrid, Spain
| | - Anthony D Barnosky
- Jasper Ridge Biological Preserve, Stanford University, Stanford, CA, USA
| | - Klement Tockner
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany.,Institute of Biology, Freie Universität Berlin, Berlin, Germany.,Austrian Science Fund FWF, Vienna, Austria
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22
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Future large hydropower dams impact global freshwater megafauna. Sci Rep 2019; 9:18531. [PMID: 31811208 PMCID: PMC6898151 DOI: 10.1038/s41598-019-54980-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 11/21/2019] [Indexed: 11/09/2022] Open
Abstract
Dam construction comes with severe social, economic and ecological impacts. From an ecological point of view, habitat types are altered and biodiversity is lost. Thus, to identify areas that deserve major attention for conservation, existing and planned locations for (hydropower) dams were overlapped, at global extent, with the contemporary distribution of freshwater megafauna species with consideration of their respective threat status. Hydropower development will disproportionately impact areas of high freshwater megafauna richness in South America, South and East Asia, and the Balkan region. Sub-catchments with a high share of threatened species are considered to be most vulnerable; these are located in Central America, Southeast Asia and in the regions of the Black and Caspian Sea. Based on this approach, planned dam locations are classified according to their potential impact on freshwater megafauna species at different spatial scales, attention to potential conflicts between climate mitigation and biodiversity conservation are highlighted, and priorities for freshwater management are recommended.
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23
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He F, Zarfl C, Bremerich V, David JNW, Hogan Z, Kalinkat G, Tockner K, Jähnig SC. The global decline of freshwater megafauna. GLOBAL CHANGE BIOLOGY 2019; 25:3883-3892. [PMID: 31393076 DOI: 10.1111/gcb.14753] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 06/05/2019] [Indexed: 05/12/2023]
Abstract
Freshwater ecosystems are among the most diverse and dynamic ecosystems on Earth. At the same time, they are among the most threatened ecosystems but remain underrepresented in biodiversity research and conservation efforts. The rate of decline of vertebrate populations is much higher in freshwaters than in terrestrial or marine realms. Freshwater megafauna (i.e., freshwater animals that can reach a body mass ≥30 kg) are intrinsically prone to extinction due to their large body size, complex habitat requirements and slow life-history strategies such as long life span and late maturity. However, population trends and distribution changes of freshwater megafauna, at continental or global scales, remain unclear. In the present study, we compiled population data of 126 freshwater megafauna species globally from the Living Planet Database and available literature, and distribution data of 44 species inhabiting Europe and the United States from literature and databases of the International Union for Conservation of Nature and NatureServe. We quantified changes in population abundance and distribution range of freshwater megafauna species. Globally, freshwater megafauna populations declined by 88% from 1970 to 2012, with the highest declines in the Indomalaya and Palearctic realms (-99% and -97%, respectively). Among taxonomic groups, mega-fishes exhibited the greatest global decline (-94%). In addition, freshwater megafauna experienced major range contractions. For example, distribution ranges of 42% of all freshwater megafauna species in Europe contracted by more than 40% of historical areas. We highlight the various sources of uncertainty in tracking changes in populations and distributions of freshwater megafauna, such as the lack of monitoring data and taxonomic and spatial biases. The detected trends emphasize the critical plight of freshwater megafauna globally and highlight the broader need for concerted, targeted and timely conservation of freshwater biodiversity.
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Affiliation(s)
- Fengzhi He
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- School of Geography, Queen Mary University of London, London, UK
| | - Christiane Zarfl
- Center for Applied Geosciences, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Vanessa Bremerich
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Jonathan N W David
- School of Geography and the Environment, University of Oxford, Oxford, UK
| | - Zeb Hogan
- Department of Biology, University of Nevada, Reno, NV, USA
| | - Gregor Kalinkat
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
| | - Klement Tockner
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
- Institute of Biology, Freie Universität Berlin, Berlin, Germany
- Austrian Science Fund (FWF), Vienna, Austria
| | - Sonja C Jähnig
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany
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24
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Kundu S, Tyagi K, Pakrashi A, Kumar V, Kosygin L, Rath S, Das U, Chandra K. DNA barcoding of freshwater fishes from the transboundary river of Indo-Bhutan: multiple clades and cryptic diversity. MITOCHONDRIAL DNA PART B-RESOURCES 2019; 4:2527-2532. [PMID: 33365612 PMCID: PMC7687587 DOI: 10.1080/23802359.2019.1640079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The species diversity of freshwater fishes from the transboundary river, Jaldhaka is still unknown to the scientific communities. We generated 40 DNA barcode sequences of 16 morphologically identified freshwater fishes and compared genetically with the database sequences. Ten species (Acanthocobitis botia, Barilius bendelisis, Crossocheilus latius, Channa punctata, Channa quinquefasciata, Garra gotyla, Garra kempi, Opsarius barna, Psilorhynchus balitora, and Pseudecheneis sulcata) showed unique haplotypes in the studied riverine system. Further, the estimated genetic divergences, BA tree topology, and ABGD species delimitation methods revealed the presence of cryptic diversity in Badis badis, Garra annandalei, G. gotyla, G. kempi, P. balitora, Rasbora daniconius, and Pethia ticto. The study suggested more exhaustive sampling and generation of more molecular data to strengthen the fact. The aimed integrated approach will be helpful to detect the extant species diversity, helps to reevaluate the checklist and promote sustainable conservation management to protect this unparalleled ecosystem.
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Affiliation(s)
- Shantanu Kundu
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Kaomud Tyagi
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Avas Pakrashi
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Vikas Kumar
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Laishram Kosygin
- Freshwater Fish Section, Zoological Survey of India, Kolkata, India
| | - Shibananda Rath
- Freshwater Fish Section, Zoological Survey of India, Kolkata, India
| | - Ujjal Das
- Freshwater Fish Section, Zoological Survey of India, Kolkata, India
| | - Kailash Chandra
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India.,Freshwater Fish Section, Zoological Survey of India, Kolkata, India
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25
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Kundu S, Chandra K, Tyagi K, Pakrashi A, Kumar V. DNA barcoding of freshwater fishes from Brahmaputra River in Eastern Himalaya biodiversity hotspot. MITOCHONDRIAL DNA PART B-RESOURCES 2019; 4:2411-2419. [PMID: 33365567 PMCID: PMC7710314 DOI: 10.1080/23802359.2019.1637290] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The genetic diversity of freshwater fishes is still anonymous in several drainage systems in northeast India. Moreover, the comparative genetic analysis is largely sporadic to judge their actual diversity and true status. We generated 89 DNA barcodes of 40 morphologically identified fishes collected from two major tributaries of Brahmaputra River. The comparative study revealed that most of the species were clearly discriminated by their estimated genetic distances and monophyletic clustering in Bayesian (BA) tree. Considering the genetic divergence (2%) for species discrimination boundary, the high genetic diversity (2.36–10.73%) was detected in 11 species (Macrognathus pancalus, Channa punctata, Puntius terio, Bangana ariza, Garra arupi, Badis badis, Mystus vittatus, Rita rita, Gagata cenia, Mastacembelus armatus, and Danio dangila), which signified the occurrence of concealed genetic diversity in this ecozone. However, the insignificant genetic distances were also noticed in few reportedly valid species: Channa stiktos and C. ornatipinnis (1.43%); Mystus ngasep, M. rufescens, and M. carcio (0.4%); Glyptothorax trilineatus, G. churamanii, and G. verrucosus (0.4%); Botia almorhae, B. histrionica, B. lohachata, and B. rostrata (0–0.4%); Barilius barilia and B. vagra (0.4%); Batasio merianiensis and B. tengana (1.2%); Puntius chola and P. fraseri (0%), Schistura beavani and S. paucireticulata (0%); hence to validate this species, generation of more barcode data was required from their types or topotypes. The present study would help to develop conservation schemes for the native species and collegiate ecosystem, which associated with the livelihoods of millions of ethnic communities in this region.
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Affiliation(s)
- Shantanu Kundu
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Kailash Chandra
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Kaomud Tyagi
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Avas Pakrashi
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
| | - Vikas Kumar
- Centre for DNA Taxonomy, Molecular Systematics Division, Zoological Survey of India, Kolkata, India
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26
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He F, Jähnig SC. Put freshwater megafauna on the table before they are eaten to extinction. Conserv Lett 2019. [DOI: 10.1111/conl.12662] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Fengzhi He
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries Berlin Germany
- Institute of BiologyFreie Universität Berlin Berlin Germany
- School of GeographyQueen Mary University of London London UK
| | - Sonja C. Jähnig
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries Berlin Germany
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27
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Dinerstein E, Vynne C, Sala E, Joshi AR, Fernando S, Lovejoy TE, Mayorga J, Olson D, Asner GP, Baillie JEM, Burgess ND, Burkart K, Noss RF, Zhang YP, Baccini A, Birch T, Hahn N, Joppa LN, Wikramanayake E. A Global Deal For Nature: Guiding principles, milestones, and targets. SCIENCE ADVANCES 2019; 5:eaaw2869. [PMID: 31016243 PMCID: PMC6474764 DOI: 10.1126/sciadv.aaw2869] [Citation(s) in RCA: 185] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 03/28/2019] [Indexed: 05/22/2023]
Abstract
The Global Deal for Nature (GDN) is a time-bound, science-driven plan to save the diversity and abundance of life on Earth. Pairing the GDN and the Paris Climate Agreement would avoid catastrophic climate change, conserve species, and secure essential ecosystem services. New findings give urgency to this union: Less than half of the terrestrial realm is intact, yet conserving all native ecosystems-coupled with energy transition measures-will be required to remain below a 1.5°C rise in average global temperature. The GDN targets 30% of Earth to be formally protected and an additional 20% designated as climate stabilization areas, by 2030, to stay below 1.5°C. We highlight the 67% of terrestrial ecoregions that can meet 30% protection, thereby reducing extinction threats and carbon emissions from natural reservoirs. Freshwater and marine targets included here extend the GDN to all realms and provide a pathway to ensuring a more livable biosphere.
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Affiliation(s)
| | | | - E. Sala
- National Geographic Society, Washington, DC, USA
| | - A. R. Joshi
- University of Minnesota, Minneapolis, MN, USA
| | | | | | - J. Mayorga
- National Geographic Society, Washington, DC, USA
- University of California, Santa Barbara, Santa Barbara, CA, USA
| | - D. Olson
- Zoological Society of London, London, UK
| | | | | | - N. D. Burgess
- UN Environment World Conservation Monitoring Centre, Cambridge, UK
| | - K. Burkart
- Leonardo DiCaprio Foundation, Los Angeles, CA, USA
| | - R. F. Noss
- Florida Institute for Conservation Science, Chuluota, FL, USA
| | - Y. P. Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - A. Baccini
- Woods Hole Research Center, Woods Hole, MA, USA
| | | | - N. Hahn
- RESOLVE, Washington, DC, USA
- Colorado State University, Fort Collins, CO, USA
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28
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Kochalski S, Riepe C, Fujitani M, Aas Ø, Arlinghaus R. Public perception of river fish biodiversity in four European countries. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2019; 33:164-175. [PMID: 29956374 DOI: 10.1111/cobi.13180] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 04/13/2018] [Accepted: 06/21/2018] [Indexed: 06/08/2023]
Abstract
Public support for biodiversity conservation is shaped by people's values and their knowledge, beliefs, and attitudes toward the environment. We conducted the first multinational representative survey of the general public's perceptions of river fish biodiversity in France, Germany, Norway, and Sweden. For the online survey, 1000 respondents per country were randomly selected from large panels following country-specific quotas set on age, gender, and educational level. Questions covered people's level of knowledge, beliefs, values, and attitudes toward river fish, environmental threats, and conservation measures. We found that the public had limited knowledge of freshwater fishes. Two non-native species, rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis), were widely perceived as native, whereas native Atlantic salmon (Salmo salar) was mostly classified as native in Scandinavia and largely as non-native in central Europe. These results suggest an extinction of experience paralleling the extirpation or decline of salmon stocks in countries such as Germany and France. Respondents thought pollution was the dominant threat to riverine fish biodiversity. In reality, habitat loss, dams, and the spread of non-native fishes are equally important. Despite limited biological knowledge, respondents from all countries held an overwhelmingly proecological worldview, supported conservation stocking, and appreciated native fishes, although only a minority interacted with them directly. Differences among the 4 countries related to several conservation issues. For example, threats to biodiversity stemming from aquaculture were perceived as more prevalent in Norway compared with the other 3 countries. Promoting fish conservation based on charismatic species and use values of fishes may work well in countries with a strong economic and cultural link to the freshwater environment, such as Norway. In countries where people rather abstractly care for nature, focusing conservation messaging on broader ecosystem traits and non-use values of fishes is likely to win more support.
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Affiliation(s)
- Sophia Kochalski
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587, Berlin, Germany
| | - Carsten Riepe
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587, Berlin, Germany
| | - Marie Fujitani
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587, Berlin, Germany
- Leibniz Centre for Tropical Marine Research, Fahrenheitstraße 6, 28359, Bremen, Germany
| | - Øystein Aas
- Norwegian Institute for Nature Research, Vormstuguvegen 40, 2624, Lillehammer, Norway
- Norwegian University of Life Sciences, Universitetstunet 3, 1430, Ås, Norway
| | - Robert Arlinghaus
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587, Berlin, Germany
- Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany
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29
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Reid AJ, Carlson AK, Creed IF, Eliason EJ, Gell PA, Johnson PTJ, Kidd KA, MacCormack TJ, Olden JD, Ormerod SJ, Smol JP, Taylor WW, Tockner K, Vermaire JC, Dudgeon D, Cooke SJ. Emerging threats and persistent conservation challenges for freshwater biodiversity. Biol Rev Camb Philos Soc 2018; 94:849-873. [PMID: 30467930 DOI: 10.1111/brv.12480] [Citation(s) in RCA: 691] [Impact Index Per Article: 115.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 12/19/2022]
Abstract
In the 12 years since Dudgeon et al. (2006) reviewed major pressures on freshwater ecosystems, the biodiversity crisis in the world's lakes, reservoirs, rivers, streams and wetlands has deepened. While lakes, reservoirs and rivers cover only 2.3% of the Earth's surface, these ecosystems host at least 9.5% of the Earth's described animal species. Furthermore, using the World Wide Fund for Nature's Living Planet Index, freshwater population declines (83% between 1970 and 2014) continue to outpace contemporaneous declines in marine or terrestrial systems. The Anthropocene has brought multiple new and varied threats that disproportionately impact freshwater systems. We document 12 emerging threats to freshwater biodiversity that are either entirely new since 2006 or have since intensified: (i) changing climates; (ii) e-commerce and invasions; (iii) infectious diseases; (iv) harmful algal blooms; (v) expanding hydropower; (vi) emerging contaminants; (vii) engineered nanomaterials; (viii) microplastic pollution; (ix) light and noise; (x) freshwater salinisation; (xi) declining calcium; and (xii) cumulative stressors. Effects are evidenced for amphibians, fishes, invertebrates, microbes, plants, turtles and waterbirds, with potential for ecosystem-level changes through bottom-up and top-down processes. In our highly uncertain future, the net effects of these threats raise serious concerns for freshwater ecosystems. However, we also highlight opportunities for conservation gains as a result of novel management tools (e.g. environmental flows, environmental DNA) and specific conservation-oriented actions (e.g. dam removal, habitat protection policies, managed relocation of species) that have been met with varying levels of success. Moving forward, we advocate hybrid approaches that manage fresh waters as crucial ecosystems for human life support as well as essential hotspots of biodiversity and ecological function. Efforts to reverse global trends in freshwater degradation now depend on bridging an immense gap between the aspirations of conservation biologists and the accelerating rate of species endangerment.
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Affiliation(s)
- Andrea J Reid
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology, Carleton University, Ottawa, K1S 5B6, Canada
| | - Andrew K Carlson
- Center for Systems Integration and Sustainability, Department of Fisheries and Wildlife and Ecology, Evolutionary Biology, and Behavior, Michigan State University, East Lansing, MI 48824, U.S.A
| | - Irena F Creed
- School of Environment and Sustainability, University of Saskatchewan, Saskatoon, S7N 5C8, Canada
| | - Erika J Eliason
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93117, U.S.A
| | - Peter A Gell
- School of Life and Health Sciences, University Drive, Federation University Australia, Mount Helen, 3350, Australia
| | - Pieter T J Johnson
- Ecology & Evolutionary Biology, University of Colorado, Boulder, CO 80309, U.S.A
| | - Karen A Kidd
- Department of Biology and School of Geography and Earth Sciences, McMaster University, Hamilton, L8S 4K1, Canada
| | - Tyson J MacCormack
- Department of Chemistry and Biochemistry, Mount Allison University, Sackville, E4L 1G8, Canada
| | - Julian D Olden
- School of Aquatic and Fishery Science, University of Washington, Seattle, WA 98195-5020, U.S.A
| | - Steve J Ormerod
- Water Research Institute & School of Biosciences, Cardiff University, Cardiff, CF10 3AX, U.K
| | - John P Smol
- Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen's University, Kingston, K7L 3N6, Canada
| | - William W Taylor
- Center for Systems Integration and Sustainability, Department of Fisheries and Wildlife and Ecology, Evolutionary Biology, and Behavior, Michigan State University, East Lansing, MI 48824, U.S.A
| | - Klement Tockner
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, 12587, Germany
| | - Jesse C Vermaire
- Institute of Environmental Science, Carleton University, Ottawa, K1S 5B6, Canada
| | - David Dudgeon
- School of Biological Sciences, The University of Hong Kong, Hong Kong, China
| | - Steven J Cooke
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology, Carleton University, Ottawa, K1S 5B6, Canada.,Institute of Environmental Science, Carleton University, Ottawa, K1S 5B6, Canada
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30
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Pinder AC, Manimekalan A, Knight JDM, Krishnankutty P, Britton JR, Philip S, Dahanukar N, Raghavan R. Resolving the taxonomic enigma of the iconic game fish, the hump-backed mahseer from the Western Ghats biodiversity hotspot, India. PLoS One 2018; 13:e0199328. [PMID: 29924871 PMCID: PMC6010267 DOI: 10.1371/journal.pone.0199328] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 06/05/2018] [Indexed: 11/24/2022] Open
Abstract
Growing to lengths and weights exceeding 1.5 m and 45 kg, the hump-backed mahseer fish of the Western Ghats biodiversity hotspot, India, is an iconic, mega-faunal species that is globally recognized as a premier freshwater game fish. Despite reports of their high extinction risk, conservation approaches are currently constrained by their lack of valid taxonomic identity. Using an integrative approach, incorporating morphology, molecular analysis and historical photographs, this fish can now be revealed to be conspecific with Tor remadevii, a species lacking a common name, that was initially, but poorly, described in 2007 from the River Pambar, a tributary of the River Cauvery in Kerala. Currently known to be endemic and restricted to the River Cauvery basin in the Western Ghats, T. remadevii is distinguished from congeners by its prominent hump originating above the pre-opercle and extending to the origin of the dorsal fin, a well-developed mandible resulting in a terminal or slightly superior mouth position, and the dorsal orientation of the eyes. While body colouration varies (silver, bronze, greenish) and is not considered a reliable diagnostic character, orange coloration of the caudal fin (sometimes extending to all fins) is considered a consistent characteristic. Having been first brought to the attention of the scientific community in 1849, and the recreational angling (game fishing) community in 1873, it has taken over 150 years to finally provide this iconic fish with a valid scientific name. This taxonomic clarity should now assist development and delivery of urgent conservation actions commensurate with their extinction risk.
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Affiliation(s)
- Adrian C. Pinder
- Faculty of Science and Technology, Bournemouth University, Dorset, United Kingdom
- Mahseer Trust, Freshwater Biological Association, Wareham, Dorset, United Kingdom
- * E-mail:
| | | | - J. D. Marcus Knight
- India Ministry of Environment Forest and Climate Change, Government of India, New Delhi, India
| | | | - J. Robert Britton
- Faculty of Science and Technology, Bournemouth University, Dorset, United Kingdom
| | - Siby Philip
- Department of Zoology, Nirmalagiri College, Kannur, India
| | - Neelesh Dahanukar
- Indian Institute of Science Education and Research, Pune, India
- Zoo Outreach Organization (ZOO), Coimbatore, India
| | - Rajeev Raghavan
- Mahseer Trust, Freshwater Biological Association, Wareham, Dorset, United Kingdom
- Zoo Outreach Organization (ZOO), Coimbatore, India
- Department of Fisheries Resource Management, Kerala University of Fisheries and Ocean Studies Kochi, Kerala, India
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31
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He F, Bremerich V, Zarfl C, Geldmann J, Langhans SD, David JNW, Darwall W, Tockner K, Jähnig SC. Freshwater megafauna diversity: Patterns, status and threats. DIVERS DISTRIB 2018. [DOI: 10.1111/ddi.12780] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Affiliation(s)
- Fengzhi He
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries; Berlin Germany
- Institute of Biology; Freie Universität Berlin; Berlin Germany
- School of Geography; Queen Mary University of London; London UK
| | - Vanessa Bremerich
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries; Berlin Germany
| | - Christiane Zarfl
- Center for Applied Geosciences; Eberhard Karls Universität Tübingen; Tübingen Germany
| | - Jonas Geldmann
- Department of Zoology; Conservation Science Group; University of Cambridge; Cambridge UK
| | - Simone D. Langhans
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries; Berlin Germany
| | | | - William Darwall
- Freshwater Biodiversity Unit; IUCN Global Species Programme; Cambridge UK
| | - Klement Tockner
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries; Berlin Germany
- Institute of Biology; Freie Universität Berlin; Berlin Germany
- Austrian Science Fund (FWF); Vienna Austria
| | - Sonja C. Jähnig
- Leibniz-Institute of Freshwater Ecology and Inland Fisheries; Berlin Germany
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32
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Reply to Kalinkat et al.: Smallest terrestrial vertebrates are highly imperiled. Proc Natl Acad Sci U S A 2017; 114:E10265. [PMID: 29122936 DOI: 10.1073/pnas.1717570114] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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