1
|
Cushway KC, Geist J, Schwalb AN. Surviving global change: a review of the impacts of drought and dewatering on freshwater mussels. Biol Rev Camb Philos Soc 2024. [PMID: 39262112 DOI: 10.1111/brv.13142] [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: 11/14/2023] [Revised: 08/23/2024] [Accepted: 08/29/2024] [Indexed: 09/13/2024]
Abstract
The increase in the frequency and intensity of droughts and heatwaves caused by climate change poses a major threat to biodiversity. In aquatic systems, sedentary species such as freshwater mussels are generally considered more vulnerable to changes in habitat conditions than mobile species such as fish. As mussels provide important ecosystem services, understanding the impacts of drought on freshwater mussels is of particular importance for the management of overall functioning of aquatic ecosystems. We used a comprehensive literature search to provide a systematic overview of direct and indirect effects of drought on freshwater mussels (Bivalvia: Unionida) and an evaluation of mitigation strategies. We found that drought studies were concentrated mostly in the USA, with a focus on the Unionidae family. Topics ranged from the physiological effects of high temperatures, emersion, and hypoxia/anoxia to behavioural and reproductive consequences of drought and the implications for biotic interactions and ecosystem services. Studies spanned all levels of biological organization, from individual responses to population- and community-level impacts and ecosystem-wide effects. We identified several knowledge gaps, including a paucity of trait-based evaluation of drought consequences, limited understanding of thermal and desiccation tolerance at the species level, and the synergistic effects of multiple drought stressors on mussels. Although we found many studies provided suggestions concerning management of populations, habitat conditions, and anthropogenic water use, a systematic approach and testing of recommended mitigation strategies is largely lacking, creating challenges for managers aiming to conserve freshwater mussel communities and populations in light of climate change.
Collapse
Affiliation(s)
- Kiara C Cushway
- Texas State University, 601 University Drive, San Marcos, TX, 78666, USA
| | - Juergen Geist
- Technical University Munich, Mühlenweg 18-22, Freising, 85354, Germany
| | - Astrid N Schwalb
- Texas State University, 601 University Drive, San Marcos, TX, 78666, USA
| |
Collapse
|
2
|
Langhammer PF, Bull JW, Bicknell JE, Oakley JL, Brown MH, Bruford MW, Butchart SHM, Carr JA, Church D, Cooney R, Cutajar S, Foden W, Foster MN, Gascon C, Geldmann J, Genovesi P, Hoffmann M, Howard-McCombe J, Lewis T, Macfarlane NBW, Melvin ZE, Merizalde RS, Morehouse MG, Pagad S, Polidoro B, Sechrest W, Segelbacher G, Smith KG, Steadman J, Strongin K, Williams J, Woodley S, Brooks TM. The positive impact of conservation action. Science 2024; 384:453-458. [PMID: 38662833 DOI: 10.1126/science.adj6598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 03/14/2024] [Indexed: 05/03/2024]
Abstract
Governments recently adopted new global targets to halt and reverse the loss of biodiversity. It is therefore crucial to understand the outcomes of conservation actions. We conducted a global meta-analysis of 186 studies (including 665 trials) that measured biodiversity over time and compared outcomes under conservation action with a suitable counterfactual of no action. We find that in two-thirds of cases, conservation either improved the state of biodiversity or at least slowed declines. Specifically, we find that interventions targeted at species and ecosystems, such as invasive species control, habitat loss reduction and restoration, protected areas, and sustainable management, are highly effective and have large effect sizes. This provides the strongest evidence to date that conservation actions are successful but require transformational scaling up to meet global targets.
Collapse
Affiliation(s)
- Penny F Langhammer
- Re:wild, PO Box 129, Austin, TX 78767, USA
- Arizona State University, School of Life Sciences, PO Box 874501, Tempe, AZ 85287, USA
| | - Joseph W Bull
- Department of Biology, University of Oxford, 11a Mansfield Rd, Oxford OX1 3SZ, UK
- Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury CT2 7NR, UK
- Wild Business Ltd, London, UK
| | - Jake E Bicknell
- Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury CT2 7NR, UK
| | | | | | - Michael W Bruford
- School of Biosciences and Sustainable Places Research Institute, Cathays Park, Cardiff CF10 3AX, UK
- IUCN SSC Conservation Genetics Specialist Group, 28 rue Mauverney, 1196 Gland, Switzerland
| | - Stuart H M Butchart
- BirdLife International, David Attenborough Building, Pembroke Street, Cambridge CB2 3QZ, UK
- Department of Zoology, University of Cambridge, Downing St., Cambridge CB2 3EJ, UK
| | - Jamie A Carr
- Leverhulme Centre for Anthropocene Biodiversity, University of York, York YO10 15DD, UK
- Department of Environment and Geography, University of York, York YO10 5DD, UK
- IUCN SSC Climate Change Specialist Group, 28 rue Mauverney, 1196 Gland, Switzerland
| | - Don Church
- Re:wild, PO Box 129, Austin, TX 78767, USA
| | - Rosie Cooney
- CEESP/SSC IUCN Sustainable Use and Livelihoods Specialist Group, 28 rue Mauverney, 1196 Gland, Switzerland
- Fenner School of Environment and Society, Australian National University, ACT 2601, Australia
| | | | - Wendy Foden
- IUCN SSC Climate Change Specialist Group, 28 rue Mauverney, 1196 Gland, Switzerland
- South African National Parks, Cape Research Centre, Tokai, Cape Town, 7966, South Africa
- FitzPatrick Institute of African Ornithology, Rondebosch, Cape Town, 7701, South Africa
- Global Change Biology Group, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
| | | | - Claude Gascon
- The Global Environment Facility, 1818 H Street NW, Washington, DC 20433, USA
| | - Jonas Geldmann
- Department of Zoology, University of Cambridge, Downing St., Cambridge CB2 3EJ, UK
- Center for Macroecology, Evolution and Climate, GLOBE Institute, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen E, Denmark
| | - Piero Genovesi
- Institute for Environmental Protection and Research, Via Vitaliano Brancati 48, 00144 Rome, Italy
- IUCN SSC Invasive Species Specialist Group, 00144 Rome, Italy
- Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
| | - Michael Hoffmann
- IUCN Species Survival Commission, 28 rue Mauverney, 1196 Gland, Switzerland
- Zoological Society of London, Regent's Park, London NW1 4RY, UK
| | - Jo Howard-McCombe
- School of Biosciences, Cardiff University, The Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
- RZSS WildGenes, Conservation Department, Royal Zoological Society of Scotland, Edinburgh EH12 6TS, UK
| | - Tiffany Lewis
- Arizona State University, 427 E. Tyler Mall, Tempe, AZ 85281, USA
| | | | - Zoe E Melvin
- School of Biosciences, Cardiff University, The Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
- Bangor University, School of Natural Sciences, Deiniol Road, Bangor, Gwynedd, Wales LL57 2UW, UK
| | | | - Meredith G Morehouse
- LLaves: Keys to Bilingual Conservation, LLC, 346 Mayberry Hill Road, Casco, Maine 04015, USA
| | - Shyama Pagad
- University of Auckland, Auckland 1072, New Zealand
| | - Beth Polidoro
- IUCN Species Survival Commission, 28 rue Mauverney, 1196 Gland, Switzerland
- Arizona State University, 4701 W. Thunderbird Rd, Glendale, AZ 85382, USA
| | | | - Gernot Segelbacher
- IUCN SSC Conservation Genetics Specialist Group, 28 rue Mauverney, 1196 Gland, Switzerland
- University Freiburg, Tennenbacher Str. 4, 79106 Freiburg, Germany
| | - Kevin G Smith
- IUCN, The David Attenborough Building, Pembroke St, Cambridge CB2 3QZ, UK
| | - Janna Steadman
- Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury CT2 7NR, UK
| | - Kyle Strongin
- Arizona State University, 800 S. Cady Mall, Tempe, AZ 85281, USA
| | - Jake Williams
- Imperial College London, Silwood Park, Ascot SL5 7PY, UK
| | - Stephen Woodley
- IUCN World Commission on Protected Areas, 64 Juniper Road, Chelsea, Quebec J9B 1T3, Canada
| | - Thomas M Brooks
- IUCN, 28 rue Mauverney, 1196 Gland, Switzerland
- World Agroforestry Center, University of The Philippines Los Baños, Laguna, Philippines
- Institute for Marine & Antarctic Studies, University of Tasmania, Hobart, Australia
| |
Collapse
|
3
|
Lopez JW, Hartnett RN, Parr TB, Vaughn CC. Ecosystem bioelement variability is associated with freshwater animal aggregations at the aquatic-terrestrial interface. Oecologia 2023; 202:795-806. [PMID: 37582947 DOI: 10.1007/s00442-023-05437-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 08/08/2023] [Indexed: 08/17/2023]
Abstract
The impacts of animals on the biogeochemical cycles of major bioelements like C, N, and P are well-studied across ecosystem types. However, more than 20 elements are necessary for life. The feedbacks between animals and the biogeochemical cycles of the other bioelements are an emerging research priority. We explored how much freshwater mussels (Bivalvia: Unionoida) were related to variability in ecosystem pools of 10 bioelements (Ca, Cu, Fe, K, Mn, Na, Mg, P, S and Zn) in streams containing a natural mussel density gradient in the US Interior Highlands. We studied the concentrations of these bioelements across the aquatic-terrestrial interface-in the porewater of riverine gravel bars, and the emergent macrophyte Justicia americana. Higher mussel density was associated with increased calcium in gravel bars and macrophytes. Mussel density also correlated with variability in iron and other redox-sensitive trace elements in gravel bars and macrophytes, although this relationship was mediated by sediment grain size. We found that two explanations for the patterns we observed are worthy of further research: (1) increased calcium availability in gravel bars near denser mussel aggregations may be a product of the buildup and dissolution of shells in the gravel bar, and (2) mussels may alter redox conditions, and thus elemental availability in gravel bars with fine sediments, either behaviorally or through physical structure provided by shell material. A better understanding of the physical and biogeochemical impacts of animals on a wide range of elemental cycles is thus necessary to conserve the societal value of freshwater ecosystems.
Collapse
Affiliation(s)
- Jonathan W Lopez
- Department of Biology, University of Oklahoma, Norman, OK, USA.
- Oklahoma Biological Survey, University of Oklahoma, Norman, OK, USA.
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL, USA.
| | - Rachel N Hartnett
- Department of Integrative Biology, Oklahoma State University, Stillwater, OK, USA
- Department of Science, Mount Saint Mary's University, Emmitsburg, MD, USA
| | - Thomas B Parr
- Oklahoma Biological Survey, University of Oklahoma, Norman, OK, USA
- National Park Service, Great Lakes Inventory and Monitoring Network, Ashland, WI, USA
| | - Caryn C Vaughn
- Department of Biology, University of Oklahoma, Norman, OK, USA
- Oklahoma Biological Survey, University of Oklahoma, Norman, OK, USA
| |
Collapse
|
4
|
Datry T, Truchy A, Olden JD, Busch MH, Stubbington R, Dodds WK, Zipper S, Yu S, Messager ML, Tonkin JD, Kaiser KE, Hammond JC, Moody EK, Burrows RM, Sarremejane R, DelVecchia AG, Fork ML, Little CJ, Walker RH, Walters AW, Allen D. Causes, Responses, and Implications of Anthropogenic versus Natural Flow Intermittence in River Networks. Bioscience 2022. [DOI: 10.1093/biosci/biac098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Abstract
Rivers that do not flow year-round are the predominant type of running waters on Earth. Despite a burgeoning literature on natural flow intermittence (NFI), knowledge about the hydrological causes and ecological effects of human-induced, anthropogenic flow intermittence (AFI) remains limited. NFI and AFI could generate contrasting hydrological and biological responses in rivers because of distinct underlying causes of drying and evolutionary adaptations of their biota. We first review the causes of AFI and show how different anthropogenic drivers alter the timing, frequency and duration of drying, compared with NFI. Second, we evaluate the possible differences in biodiversity responses, ecological functions, and ecosystem services between NFI and AFI. Last, we outline knowledge gaps and management needs related to AFI. Because of the distinct hydrologic characteristics and ecological impacts of AFI, ignoring the distinction between NFI and AFI could undermine management of intermittent rivers and ephemeral streams and exacerbate risks to the ecosystems and societies downstream.
Collapse
Affiliation(s)
- Thibault Datry
- INRAE , UR RiverLy, Centre Lyon-Grenoble Auvergne-Rhône-Alpes, Villeurbanne France
| | - Amélie Truchy
- INRAE , UR RiverLy, Centre Lyon-Grenoble Auvergne-Rhône-Alpes, Villeurbanne France
| | - Julian D Olden
- School of Aquatic and Fishery Sciences, University of Washington , Seattle Washington, United States
| | - Michelle H Busch
- Department of Biology, University of Oklahoma , Norman, Oklahoma, United States
| | - Rachel Stubbington
- School of Science and Technology, Nottingham Trent University , Nottingham, England, United Kingdom
| | - Walter K Dodds
- Division of Biology, Kansas State University , Manhattan, Kansas, United States
| | - Sam Zipper
- Kansas Geological Survey, University of Kansas , Lawrence, Kansas, United States
| | - Songyan Yu
- Australian Rivers Institute, School of Environment and Science, Griffith University , Nathan, Queensland, Australia
| | - Mathis L Messager
- Department of Geography, McGill University , Montreal, Quebec, Canada
| | - Jonathan D Tonkin
- School of Biological Sciences, University of Canterbury , Auckland, New Zealand
| | - Kendra E Kaiser
- Department of Geosciences, Boise State University , Boise, Idaho, United States
| | - John C Hammond
- Department of Ecosystem Science and Sustainability, Colorado State University , Fort Collins, Colorado, United States
| | - Eric K Moody
- Department of Biology, Middlebury College , Middlebury, Vermont, United States
| | - Ryan M Burrows
- School of Ecosystem and Forest Sciences, University of Melbourne , Burnley Campus, Burnley, Victoria, Australia
| | - Romain Sarremejane
- INRAE , UR RiverLy, Centre Lyon-Grenoble Auvergne-Rhône-Alpes, Villeurbanne France
| | - Amanda G DelVecchia
- Department of Biology, Duke University , Durham, North Carolina, United States
| | - Megan L Fork
- Department of Biology, West Chester University , West Chester, Pennsylvania, United States
| | - Chelsea J Little
- Department of Biology, West Chester University , West Chester, Pennsylvania, United States
| | - Richard H Walker
- Department of Biology and Chemistry, Upper Iowa University , Fayette, Iowa, United States
| | - Annika W Walters
- Department of Zoology and Physiology, Program in Ecology, University of Wyoming , Larame, Wyoming, United States
| | - Daniel Allen
- Department of Ecosystem Science and Management, Pennsylvania State University , University Park, Pennsylvania, United States
| |
Collapse
|
5
|
Leppänen JJ, Leinikki J, Väisänen A. NiSO 4 spill inflicts varying mortality between four freshwater mussel species (including protected Unio crassus Philipsson, 1788) in a western Finnish river. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 256:113402. [PMID: 31672360 DOI: 10.1016/j.envpol.2019.113402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 10/11/2019] [Accepted: 10/13/2019] [Indexed: 06/10/2023]
Abstract
Freshwater mussels are one of the most threatened taxonomic groups in the world, and many species are on the brink of local or global extinction. Human activities have altered mussel living conditions in a plethora of ways. One of the most destructive human-induced impacts on running waters is the catastrophic spill of harmful substances, which results in massive die-offs. Even though Finland is regarded as the world's top country in terms of environmental regulation quality, riverine systems are not safe. In 2014, River Kokemäenjoki in western Finland experienced the worst NiSO4 spill in the country's history, visibly affecting the mussel community - including protected Unio crassus - along the river. Because freshwater mussel toxicology is grossly understudied (particularly in Europe), any pollution -linked die-offs offer valuable opportunities to study the issue in natural environment. Here, we report the mussel investigations from 2014 and a follow-up study conducted in 2017 in order to assess the variation in species sensitivity on nickel pollution. In total, 104 sites were sampled, and over 20 000 mussels were identified and counted. Our results indicate that the most impacted species (i.e. that which experienced the highest spill-induced mortality) was Anodonta anatina (62%), followed by Unio pictorum (32%), U. crassus (24%) and Unio tumidus (9%). The underlying reason for the sensitivity of A. anatina is not resolved, hence more research is urgently needed. The low mortality among most of the species in 2017 highlights the temporal nature of the pollution impact and the recovery potential of the mussel community. However, the case is more complex with U. crassus population, which may be experiencing delayed impacts of the spill. Because nickel is one of the most commonly produced industrial metals in the world (hence the pollution incident risk is high) and River Kokemäenjoki hosts mussel community typical for European rivers, our results may benefit many researchers and stakeholders dealing with riverine environments.
Collapse
Affiliation(s)
- Jaakko Johannes Leppänen
- Environmental Change Research Unit (ECRU), Ecosystems and Environment Research Programme, Faculty of Biological and Environmental Sciences, P.O. Box 65, 00014, University of Helsinki, Finland.
| | - Jouni Leinikki
- Alleco Ltd, Veneentekijäntie 4, 00210, Helsinki, Finland
| | - Anna Väisänen
- KVVY Tutkimus Oy, Patamäenkatu 24, 33101, Tampere, Finland
| |
Collapse
|
6
|
Hopper GW, Gido KB, Vaughn CC, Parr TB, Popejoy TG, Atkinson CL, Gates KK. Biomass distribution of fishes and mussels mediates spatial and temporal heterogeneity in nutrient cycling in streams. Oecologia 2018; 188:1133-1144. [DOI: 10.1007/s00442-018-4277-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 10/14/2018] [Indexed: 10/28/2022]
|
7
|
Randklev CR, Tsakris ET, Johnson MS, Popejoy T, Hart MA, Khan J, Geeslin D, Robertson CR. The effect of dewatering on freshwater mussel (Unionidae) community structure and the implications for conservation and water policy: A case study from a spring-fed stream in the southwestern United States. Glob Ecol Conserv 2018. [DOI: 10.1016/j.gecco.2018.e00456] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
|
8
|
Randklev CR, Miller T, Hart M, Morton J, Johnson NA, Skow K, Inoue K, Tsakiris ET, Oetker S, Smith R, Robertson C, Lopez R. A semi-arid river in distress: Contributing factors and recovery solutions for three imperiled freshwater mussels (Family Unionidae) endemic to the Rio Grande basin in North America. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 631-632:733-744. [PMID: 29544177 DOI: 10.1016/j.scitotenv.2018.03.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 03/02/2018] [Accepted: 03/03/2018] [Indexed: 06/08/2023]
Abstract
Freshwater resources in arid and semi-arid regions are in extreme demand, which creates conflicts between needs of humans and aquatic ecosystems. The Rio Grande basin in the southwestern United States and northern Mexico exemplifies this issue, as much of its aquatic biodiversity is in peril as a result of human activities. Unionid mussels have been disproportionately impacted, though the specific factors responsible for their decline remain largely unknown. This is problematic because the Rio Grande basin harbors one federally endangered unionid mussel (Popenaias popeii, Texas Hornshell) plus two other mussel species (Potamilus metnecktayi, Salina Mucket; and Truncilla cognata, Mexican Fawnsfoot), which are also being considered for listing under the U.S. Endangered Species Act. To date, surveys for these species have not corrected for variability in detection so current range estimates may be inaccurate. Using single occupancy-modeling to estimate detection and occupancy at 115 sites along ~800 river kilometers of the Rio Grande in Texas, we found that detection probabilities were relatively high, indicating that our survey design was efficient. In contrast, the estimated occupancy was low, indicating that our focal species were likely rare within the Rio Grande drainage. In general, the predicted occupancy of our focal species was low throughout their respective ranges, indicating possible range declines. A comparison of currently occupied ranges to presumptive ranges underscores this point. The best-approximating models indicated that occupancy was influenced by habitat, water quantity and quality, and proximity to large-scale human activities, such as dams and major urban centers. We also discuss a series of conservation options that may not only improve the long-term prognosis of our focal species but also other aquatic taxa.
Collapse
Affiliation(s)
- Charles R Randklev
- Texas A&M Natural Resources Institute and AgriLife Research Center at Dallas, Dallas, TX, United States.
| | - Tom Miller
- Environmental Science Center, Laredo Community College, Laredo, TX, United States
| | - Michael Hart
- Texas A&M Natural Resources Institute and AgriLife Research Center at Dallas, Dallas, TX, United States
| | - Jennifer Morton
- Texas A&M Natural Resources Institute and AgriLife Research Center at Dallas, Dallas, TX, United States
| | - Nathan A Johnson
- U.S. Geological Survey, Wetland and Aquatic Research Center, Gainesville, FL, United States
| | - Kevin Skow
- Texas A&M Natural Resources Institute and AgriLife Research Center at Dallas, Dallas, TX, United States
| | - Kentaro Inoue
- Texas A&M Natural Resources Institute and AgriLife Research Center at Dallas, Dallas, TX, United States
| | - Eric T Tsakiris
- Texas A&M Natural Resources Institute and AgriLife Research Center at Dallas, Dallas, TX, United States
| | - Susan Oetker
- U.S. Fish and Wildlife Service, Southwest Region, Albuquerque, NM, United States
| | - Ryan Smith
- The Nature Conservancy of Texas, San Antonio, TX, United States
| | - Clint Robertson
- Texas Parks and Wildlife Department, River Studies Program, San Marcos, TX, United States
| | - Roel Lopez
- Texas A&M Natural Resources Institute and AgriLife Research Center at Dallas, Dallas, TX, United States
| |
Collapse
|
9
|
Vaughn CC, Atkinson CL, Julian JP. Drought-induced changes in flow regimes lead to long-term losses in mussel-provided ecosystem services. Ecol Evol 2015; 5:1291-305. [PMID: 25859334 PMCID: PMC4377272 DOI: 10.1002/ece3.1442] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 01/29/2015] [Accepted: 01/31/2015] [Indexed: 11/11/2022] Open
Abstract
Extreme hydro-meteorological events such as droughts are becoming more frequent, intense, and persistent. This is particularly true in the south central USA, where rapidly growing urban areas are running out of water and human-engineered water storage and management are leading to broad-scale changes in flow regimes. The Kiamichi River in southeastern Oklahoma, USA, has high fish and freshwater mussel biodiversity. However, water from this rural river is desired by multiple urban areas and other entities. Freshwater mussels are large, long-lived filter feeders that provide important ecosystem services. We ask how observed changes in mussel biomass and community composition resulting from drought-induced changes in flow regimes might lead to changes in river ecosystem services. We sampled mussel communities in this river over a 20-year period that included two severe droughts. We then used laboratory-derived physiological rates and river-wide estimates of species-specific mussel biomass to estimate three aggregate ecosystem services provided by mussels over this time period: biofiltration, nutrient recycling (nitrogen and phosphorus), and nutrient storage (nitrogen, phosphorus, and carbon). Mussel populations declined over 60%, and declines were directly linked to drought-induced changes in flow regimes. All ecosystem services declined over time and mirrored biomass losses. Mussel declines were exacerbated by human water management, which has increased the magnitude and frequency of hydrologic drought in downstream reaches of the river. Freshwater mussels are globally imperiled and declining around the world. Summed across multiple streams and rivers, mussel losses similar to those we document here could have considerable consequences for downstream water quality although lost biofiltration and nutrient retention. While we cannot control the frequency and severity of climatological droughts, water releases from reservoirs could be used to augment stream flows and prevent compounded anthropogenic stressors.
Collapse
Affiliation(s)
- Caryn C Vaughn
- Oklahoma Biological Survey, Department of Biology, and Ecology and Evolutionary Biology Graduate Program, University of Oklahoma Norman, Oklahoma
| | - Carla L Atkinson
- Oklahoma Biological Survey, Department of Biology, and Ecology and Evolutionary Biology Graduate Program, University of Oklahoma Norman, Oklahoma ; Department of Biological Sciences, University of Alabama Tuscaloosa, Alabama
| | - Jason P Julian
- Department of Geography, Texas State University San Marcos, Texas
| |
Collapse
|