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Nolan N, Hayward MW, Klop-Toker K, Mahony M, Lemckert F, Callen A. Complex Organisms Must Deal with Complex Threats: How Does Amphibian Conservation Deal with Biphasic Life Cycles? Animals (Basel) 2023; 13:ani13101634. [PMID: 37238064 DOI: 10.3390/ani13101634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/08/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
The unprecedented rate of global amphibian decline is attributed to The Anthropocene, with human actions triggering the Sixth Mass Extinction Event. Amphibians have suffered some of the most extreme declines, and their lack of response to conservation actions may reflect challenges faced by taxa that exhibit biphasic life histories. There is an urgent need to ensure that conservation measures are cost-effective and yield positive outcomes. Many conservation actions have failed to meet their intended goals of bolstering populations to ensure the persistence of species into the future. We suggest that past conservation efforts have not considered how different threats influence multiple life stages of amphibians, potentially leading to suboptimal outcomes for their conservation. Our review highlights the multitude of threats amphibians face at each life stage and the conservation actions used to mitigate these threats. We also draw attention to the paucity of studies that have employed multiple actions across more than one life stage. Conservation programs for biphasic amphibians, and the research that guides them, lack a multi-pronged approach to deal with multiple threats across the lifecycle. Conservation management programs must recognise the changing threat landscape for biphasic amphibians to reduce their notoriety as the most threatened vertebrate taxa globally.
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Affiliation(s)
- Nadine Nolan
- Conservation Science Research Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Matthew W Hayward
- Conservation Science Research Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Kaya Klop-Toker
- Conservation Science Research Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Michael Mahony
- Conservation Science Research Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Frank Lemckert
- Eco Logical Australia Pty Ltd., Perth, WA 6000, Australia
| | - Alex Callen
- Conservation Science Research Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
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2
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Brooks GC, Wendt A, Haas CA, Roberts JH. Comparing estimates of census and effective population size in an endangered amphibian. Anim Conserv 2023. [DOI: 10.1111/acv.12871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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3
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Greene KM, Van Cleve J, Price SJ. Salamander Movement Propensity Resists Effects of Supraseasonal Drought. ICHTHYOLOGY & HERPETOLOGY 2023. [DOI: 10.1643/h2022051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Affiliation(s)
- Kathryn M. Greene
- Department of Forestry and Natural Resources, University of Kentucky, Lexington, Kentucky 40546; ORCID: (KMG) 0000-0003-0227-1982; and (SJP) 0000-0002-2388-0579; (KMG) ; and (SJP)
| | - Jeremy Van Cleve
- Department of Biology, University of Kentucky, 101 TH Morgan Building, 675 Rose Street, Lexington, Kentucky 40506; ORCID: (JVC) 0000-0003-3656-4257; (JVC)
| | - Steven J. Price
- Department of Forestry and Natural Resources, University of Kentucky, Lexington, Kentucky 40546; ORCID: (KMG) 0000-0003-0227-1982; and (SJP) 0000-0002-2388-0579; (KMG) ; and (SJP)
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4
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Durán AP, Barbosa O, Gaston KJ. Understanding the interacting factors that determine ecological effectiveness of terrestrial protected areas. J Nat Conserv 2022. [DOI: 10.1016/j.jnc.2022.126264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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5
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Divergent physiological acclimation responses to warming between two co-occurring salamander species and implications for terrestrial survival. J Therm Biol 2022; 106:103228. [DOI: 10.1016/j.jtherbio.2022.103228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/20/2022] [Accepted: 03/25/2022] [Indexed: 11/24/2022]
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6
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Brooks GC, Kindsvater HK. Early Development Drives Variation in Amphibian Vulnerability to Global Change. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.813414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Understanding how natural selection determines species’ life histories can reveal their resilience or sensitivity to anthropogenic changes. For example, the safe harbor hypothesis posits that natural selection will favor life histories that maximize the time spent in the safest life stages; a second theoretical prediction suggests that species with complex life histories will maximize the growth potential of a life stage relative to its safety. Amphibians exhibit complex life histories, with a diversity of developmental strategies occurring across taxa. Many strategies involve the complete elimination of a particular life stage, and thus provide an excellent opportunity to evaluate the main tenets of the safe harbor hypothesis and understand the consequences of this developmental variation for conservation of threatened amphibians. We develop a general framework for understanding developmental life histories of amphibians – including the special cases of paedomorphism, direct development, and viviparity – based on the relative growth potential and safety offered by aquatic and terrestrial habitat, which we tested using a global trait database. We then compare the IUCN Red List status of species differing in developmental mode, revealing that most fully aquatic species and species with an aquatic larval stage are currently of Least Concern, despite the fact that freshwater habitats are being lost at a much faster rate compared with terrestrial ecosystems. The higher proportion of direct developing and viviparous species that are threatened can be attributed to their smaller ranges, the fact that they are more likely to be found in rainforest habitats, and their relatively slow life histories. We conclude that an amphibian’s developmental mode reflects the relative costs and benefits of different habitats, and that this could contribute to the resilience or vulnerability of amphibians to future anthropogenic change.
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Hromada SJ, Iacchetta MG, Beas BJ, Flaherty J, Fulbright MC, Wild KH, Scott AF, Gienger C. Low-Intensity Agriculture Shapes Amphibian and Reptile Communities: Insights from a 10-Year Monitoring Study. HERPETOLOGICA 2021. [DOI: 10.1655/herpetologica-d-20-00007.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Steven J. Hromada
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
| | - Michael G. Iacchetta
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
| | - Benjamin J. Beas
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
| | - James Flaherty
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
| | - Michael C. Fulbright
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
| | - Kristoffer H. Wild
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
| | - A. Floyd Scott
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
| | - C.M. Gienger
- Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, TN 37040, USA
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8
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Williams ST, Elbers JP, Taylor SS. Population structure, gene flow, and sex-biased dispersal in the reticulated flatwoods salamander ( Ambystoma bishopi): Implications for translocations. Evol Appl 2021; 14:2231-2243. [PMID: 34603495 PMCID: PMC8477597 DOI: 10.1111/eva.13287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 07/26/2021] [Accepted: 07/31/2021] [Indexed: 12/02/2022] Open
Abstract
Understanding patterns of gene flow and population structure is vital for managing threatened and endangered species. The reticulated flatwoods salamander (Ambystoma bishopi) is an endangered species with a fragmented range; therefore, assessing connectivity and genetic population structure can inform future conservation. Samples collected from breeding sites (n = 5) were used to calculate structure and gene flow using three marker types: single nucleotide polymorphisms isolated from potential immune genes (SNPs), nuclear data from the major histocompatibility complex (MHC), and the mitochondrial control region. At a broad geographical scale, nuclear data (SNP and MHC) supported gene flow and little structure (F ST = 0.00-0.09) while mitochondrial structure was high (ΦST = 0.15-0.36) and gene flow was low. Mitochondrial markers also exhibited isolation by distance (IBD) between sites (p = 0.01) and within one site (p = 0.04) while nuclear markers did not show IBD between or within sites (p = 0.17 and p = 0.66). Due to the discordant results between nuclear and mitochondrial markers, our results suggest male-biased dispersal. Overall, salamander populations showed little genetic differentiation and structure with some gene flow, at least historically, among sampling sites. Given historic gene flow and a lack of population structure, carefully considered reintroductions could begin to expand the limited range of this salamander to ensure its long-term resilience.
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Affiliation(s)
- Steven T. Williams
- School of Renewable Natural ResourcesLouisiana State University AgCenterBaton RougeLouisianaUSA
| | | | - Sabrina S. Taylor
- School of Renewable Natural ResourcesLouisiana State University AgCenterBaton RougeLouisianaUSA
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Halstead BJ, Baumberger KL, Backlin AR, Kleeman PM, Wong MN, Gallegos EA, Rose JP, Fisher RN. Conservation Implications of Spatiotemporal Variation in the Terrestrial Ecology of Western Spadefoots. J Wildl Manage 2021. [DOI: 10.1002/jwmg.22095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Brian J. Halstead
- U.S. Geological Survey, Western Ecological Research Center Dixon Field Station 800 Business Park Drive, Suite D Dixon CA 95620 USA
| | - Katherine L. Baumberger
- U.S. Geological Survey, Western Ecological Research Center San Diego Field Station—Santa Ana Sub‐station 1801 East Chestnut Avenue Santa Ana CA 92701 USA
| | - Adam R. Backlin
- U.S. Geological Survey, Western Ecological Research Center San Diego Field Station—Santa Ana Sub‐station 1801 East Chestnut Avenue Santa Ana CA 92701 USA
| | - Patrick M. Kleeman
- U.S. Geological Survey, Western Ecological Research Center Dixon Field Station—Point Reyes Sub‐station 1 Bear Valley Road Point Reyes Station CA 94956 USA
| | - Monique N. Wong
- U.S. Geological Survey, Western Ecological Research Center San Diego Field Station—Santa Ana Sub‐station 1801 East Chestnut Avenue Santa Ana CA 92701 USA
| | - Elizabeth A. Gallegos
- U.S. Geological Survey, Western Ecological Research Center San Diego Field Station—Santa Ana Sub‐station 1801 East Chestnut Avenue Santa Ana CA 92701 USA
| | - Jonathan P. Rose
- U.S. Geological Survey, Western Ecological Research Center Santa Cruz Field Station 2885 Mission Street Santa Cruz CA 95060 USA
| | - Robert N. Fisher
- U.S. Geological Survey, Western Ecological Research Center San Diego Field Station 4165 Spruance Road, Suite 200 San Diego CA 92101 USA
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10
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Two for One: Conservation of Aquatic Ecosystems With Buffers Protects Terrestrial Ecosystems. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2021. [DOI: 10.3996/jfwm-21-005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
We evaluated how three widths of buffer zones on greater than or equal to 100-ha wetlands (240, 300, and 390 m) and rivers (10, 20, and 30 m) would help meet watershed conservation goals in the Upper Peninsula of Michigan, USA, and whether doing so also would protect each of the predominant types of terrestrial natural communities across the landscape. The use of buffer zones (even the narrowest widths assessed) around wetlands and riparian zones met or exceeded conservation targets in 75% of watersheds and greater than or equal to 85% of subwatersheds evaluated. Wetlands and riparian zones with buffers captured each of the predominant types of terrestrial natural community in Michigan's Upper Peninsula, but not proportionately to their availability across the entire landscape. Our work demonstrates that a landscape-conservation approach focused on wetlands and riparian zones with buffers can conserve terrestrial, wetland, and riparian ecosystems across Michigan's Upper Peninsula and may also be applicable in other areas where mapping of wetlands and rivers occurs.
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11
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Simpson DS, Forester DC, Snodgrass JW, Smith SA. Relationships among Amphibian Assemblage Structure, Wetland pH, and Forest Cover. J Wildl Manage 2021. [DOI: 10.1002/jwmg.22016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Duncan S. Simpson
- Towson University Department of Biological Sciences Towson MD 21252 USA
| | - Don C. Forester
- Towson University Department of Biological Sciences Towson MD 21252 USA
| | - Joel W. Snodgrass
- Virginia Tech Department of Fish and Wildlife Conservation 310 West Campus Drive Blacksburg VA 24061 USA
| | - Scott A. Smith
- Maryland Department of Natural Resources Wye Mills Field Office 909 Wye Mills Road Wye Mills MD 21679 USA
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12
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Burgstaller S, Leeb C, Ringler M, Gollmann G. Demography and spatial activity of fire salamanders, Salamandra salamandra (Linnaeus, 1758), in two contrasting habitats in the Vienna Woods. HERPETOZOA 2021. [DOI: 10.3897/herpetozoa.34.e58496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Understanding population dynamics is vital in amphibian conservation. To compare demography and movements, we conducted a capture-recapture study over three spring seasons in two populations of Salamandra salamandra in the Vienna Woods. The study sites differ in topography, vegetation, and the type of breeding waters. Population density in a beech forest traversed by a stream was more than twice as high as in an oak-hornbeam forest with temporary pools. Movement distances were on average higher at the latter site whereas home range estimates were similar for both sites. The sexes did not differ significantly in the observed movement patterns at either site. Annual apparent survival was mostly high (~0.85), but the estimate for females from the low-density site was lower (~0.60), indicating a higher rate of emigration or mortality.
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13
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Messerman AF, Leal M. Inter- and intraspecific variation in juvenile metabolism and water loss among five biphasic amphibian species. Oecologia 2020; 194:371-382. [PMID: 33057838 DOI: 10.1007/s00442-020-04780-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/08/2020] [Indexed: 12/16/2022]
Abstract
Population persistence is informed by the ability of individuals to cope with local abiotic conditions, which is commonly mediated by physiological traits. Among biphasic amphibians, juveniles-which are infrequently studied but play a key role in amphibian population dynamics-are the first life stage to experience terrestrial conditions following the aquatic larval stage. To illuminate phenotypic variation that may allow juveniles to survive the physiological challenges presented by this transition, we examined respiratory surface area water loss (RSAWL) and standard metabolic rates (SMR) among juveniles reared under common larval conditions for five salamander species (Ambystoma annulatum, A. maculatum, A. opacum, A. talpoideum, and A. texanum) collected across ~ 200 km of latitude in Missouri, USA. We found that SMR described 34% of variation in RSAWL, suggesting that physiological water conservation may be limited by energetic regulation among these species, and vice versa. On average, species differed in juvenile SMR and residual values of RSAWL (corrected for body size/shape) by 0.04 mL [Formula: see text] and 0.16, respectively, possibly because of distinct species ecologies. For example, A. annulatum had higher SMR and RSAWL compared to broadly distributed study species, potentially associated with a relatively narrow range of environmental conditions experienced across the small geographic distribution of A. annulatum. Latitude correlated negatively with temperature and precipitation, and positively with RSAWL, suggesting that variation in RSAWL may be adaptive to local conditions. We provide evidence that species differences likely have a genetic basis, reflecting selection favoring species divergence to effectively use distinct microhabitats.
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Affiliation(s)
- Arianne F Messerman
- Department of Biology, University of Miami, 1301 Memorial Drive, 113 Cox Science Building, Coral Gables, FL, 33146, USA.
| | - Manuel Leal
- Division of Biological Sciences, Univeristy of Missouri, 612 Hitt Street, 105 Tucker Hall, Columbia, MO, 65211, USA
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Rollins HB, Benard MF. Challenges in predicting the outcome of competition based on climate change-induced phenological and body size shifts. Oecologia 2020; 193:749-759. [PMID: 32654046 DOI: 10.1007/s00442-020-04705-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 07/04/2020] [Indexed: 11/25/2022]
Abstract
Climate change is creating warmer, earlier springs, which are causing the phenology of many organisms to shift. Additionally, as temperatures increase, the body size of many ectotherms is decreasing. However, phenological and body size shifts are not occurring at the same rates across species, even in species that live in close proximity or have similar life history. Differing rates of phenological and body-size shifts may affect ecological interactions. We investigated whether shifts in phenology and body size had a predictable effect on interspecific competition. We tested three hypotheses. First, priority effects would indicate early arriving organisms gain a competitive advantage. Second, larger organisms would be competitively superior. Third, similarly sized organisms would compete more strongly. We manipulated aquatic larval conditions to create variation in wood frog (Rana sylvatica) size at and date of metamorphosis. Wood frogs were placed in terrestrial enclosures with unmanipulated juvenile American toads (Anaxyrus americanus) where we tracked amphibian growth over 3 months. Consistent with the size superiority hypothesis, initially smaller wood frogs did not compete as strongly with toads. However, the results of the phenological shift were the opposite of our priority effects prediction: early arrival by frogs increased toad mass. Our results could indicate that toads would experience fewer negative effects of competition with wood frogs that metamorphose earlier and smaller under climate change. Our study highlights the challenges of predicting how climate change will affect interspecific interactions and emphasizes the need to investigate the role of shifts in both phenology and body size.
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Affiliation(s)
- Hilary B Rollins
- Department of Biology, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106, USA.
| | - Michael F Benard
- Department of Biology, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
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15
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Herek JS, Vargas L, Trindade SAR, Rutkoski CF, Macagnan N, Hartmann PA, Hartmann MT. Can environmental concentrations of glyphosate affect survival and cause malformation in amphibians? Effects from a glyphosate-based herbicide on Physalaemus cuvieri and P. gracilis (Anura: Leptodactylidae). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:22619-22630. [PMID: 32319061 DOI: 10.1007/s11356-020-08869-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 04/13/2020] [Indexed: 06/11/2023]
Abstract
Herbicides are the most common agrochemicals used in crops. Among them, glyphosate is the most widely applied in the world. Herbicides, especially organophosphates, have been shown to be hazardous to non-target species, including amphibians. The present study evaluated the acute and chronic effects of glyphosate-based herbicide (GBH), Roundup original® DI on tadpoles from two South American native species, Physalaemus cuvieri and P. gracilis. Spawnings were collected in the natural environment and maintained in the laboratory under controlled conditions. Acute and chronic toxicology trials began at stage 25 of Gosner (Herpetological 16:183-190, 1960). In an acute toxicity assay, seven GBH concentrations between 100 and 4500 μg a.e./L were tested over 96 h. For the chronic trials, tadpoles were subjected to both doses allowed by Brazilian legislation and to concentrations found in natural environment waters from Brazil and Argentina, between 65 and 1000 μg a.e/L over 14 days. Glyphosate had lethal effects on both studied species. Tadpoles showed shorter lengths and lower masses; that is, those that survived suffered chronic effects on growth and weight. The GBH maximum acceptable toxicant concentration for mortality and malformation was lower than the allowed level for Brazilian waters. The GBH tested in this study presented a high environmental and acute risk for the two studied species.
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Affiliation(s)
- Jéssica Samara Herek
- Laboratory of Ecology and Conservation, Federal University of Fronteira Sul, Erechim Campus, ERS 135 - Km 72, n°200, Erechim, RS, Brazil
| | - Luana Vargas
- Laboratory of Ecology and Conservation, Federal University of Fronteira Sul, Erechim Campus, ERS 135 - Km 72, n°200, Erechim, RS, Brazil
| | - Suélen Andressa Rinas Trindade
- Laboratory of Ecology and Conservation, Federal University of Fronteira Sul, Erechim Campus, ERS 135 - Km 72, n°200, Erechim, RS, Brazil
| | - Camila Fatima Rutkoski
- Laboratory of Ecology and Conservation, Federal University of Fronteira Sul, Erechim Campus, ERS 135 - Km 72, n°200, Erechim, RS, Brazil
| | - Natani Macagnan
- Laboratory of Ecology and Conservation, Federal University of Fronteira Sul, Erechim Campus, ERS 135 - Km 72, n°200, Erechim, RS, Brazil
| | - Paulo Afonso Hartmann
- Laboratory of Ecology and Conservation, Federal University of Fronteira Sul, Erechim Campus, ERS 135 - Km 72, n°200, Erechim, RS, Brazil
| | - Marilia Teresinha Hartmann
- Laboratory of Ecology and Conservation, Federal University of Fronteira Sul, Erechim Campus, ERS 135 - Km 72, n°200, Erechim, RS, Brazil.
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Edge CB, Fortin M. Habitat network topology influences the importance of ecological traps in metapopulations. Ecosphere 2020. [DOI: 10.1002/ecs2.3146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Christopher B. Edge
- Natural Resources Canada Canadian Forest Service Fredericton New Brunswick E3B5P7 Canada
| | - Marie‐Josée Fortin
- Department of Ecology and Evolutionary Biology University of Toronto Toronto Ontario M5S 3B2 Canada
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17
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Crockett JG, Bailey LL, Muths E. Highly variable rates of survival to metamorphosis in wild boreal toads (
Anaxyrus boreas boreas
). POPUL ECOL 2020. [DOI: 10.1002/1438-390x.12044] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- John G. Crockett
- Department of Fish, Wildlife, and Conservation Biology Colorado State University Fort Collins Colorado
| | - Larissa L. Bailey
- Department of Fish, Wildlife, and Conservation Biology Colorado State University Fort Collins Colorado
| | - Erin Muths
- United States Geological Survey Fort Collins Science Center Fort Collins Colorado
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18
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Messerman AF, Semlitsch RD, Leal M. Estimating Survival for Elusive Juvenile Pond‐Breeding Salamanders. J Wildl Manage 2020. [DOI: 10.1002/jwmg.21815] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Manuel Leal
- University of Missouri 612 Hitt Street, 209 Tucker Hall Columbia MO 65211 USA
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Movement and habitat selection of the western spadefoot (Spea hammondii) in southern California. PLoS One 2019; 14:e0222532. [PMID: 31581232 PMCID: PMC6776459 DOI: 10.1371/journal.pone.0222532] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 08/31/2019] [Indexed: 11/19/2022] Open
Abstract
Agricultural activity, urban development and habitat alteration have caused the disappearance of the western spadefoot (Spea hammondii) from 80% of its geographic range in southern California. Despite the western spadefoot's continuing decline, little research has been conducted on its natural history. The home range of adult spadefoots is unknown, and their use of upland habitat is poorly understood. Both factors are important for the long-term conservation of the species because adult spadefoots spend the majority of their lives away from breeding pools in self-excavated burrows. Between January 2012 and January 2013, we surgically implanted radio transmitters in 15 spadefoots at two locations and recorded their movements and habitat use. The mean distance moved between burrow locations was 18 m (SD ± 24.1 m, range1-204 m). The mean distance of burrows from the breeding pools was 40 m (SD ± 37.42 m, range 1-262 m). Rain was a significant predictor of spadefoot movement, with more rain predicting higher probability of movement and larger distances moved. At remote sensing scale (1 m) spadefoots selected grassland habitat for their burrow locations. At the microsite scale (< 1 m) spadefoots strongly selected duff over grass or shrub cover. Spadefoots burrowed in friable, sandy/loam soil with significantly less clay than random pseudoabsence points. This research enhances our understanding of a little-studied species and will contribute to the development of effective management plans for the western spadefoot.
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Homola JJ, Loftin CS, Kinnison MT. Landscape genetics reveals unique and shared effects of urbanization for two sympatric pool-breeding amphibians. Ecol Evol 2019; 9:11799-11823. [PMID: 31695889 PMCID: PMC6822048 DOI: 10.1002/ece3.5685] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 08/26/2019] [Accepted: 08/30/2019] [Indexed: 01/05/2023] Open
Abstract
Metapopulation-structured species can be negatively affected when landscape fragmentation impairs connectivity. We investigated the effects of urbanization on genetic diversity and gene flow for two sympatric amphibian species, spotted salamanders (Ambystoma maculatum) and wood frogs (Lithobates sylvaticus), across a large (>35,000 km2) landscape in Maine, USA, containing numerous natural and anthropogenic gradients. Isolation-by-distance (IBD) patterns differed between the species. Spotted salamanders showed a linear and relatively high variance relationship between genetic and geographic distances (r = .057, p < .001), whereas wood frogs exhibited a strongly nonlinear and lower variance relationship (r = 0.429, p < .001). Scale dependence analysis of IBD found gene flow has its most predictable influence (strongest IBD correlations) at distances up to 9 km for spotted salamanders and up to 6 km for wood frogs. Estimated effective migration surfaces revealed contrasting patterns of high and low genetic diversity and gene flow between the two species. Population isolation, quantified as the mean IBD residuals for each population, was associated with local urbanization and less genetic diversity in both species. The influence of geographic proximity and urbanization on population connectivity was further supported by distance-based redundancy analysis and multiple matrix regression with randomization. Resistance surface modeling found interpopulation connectivity to be influenced by developed land cover, light roads, interstates, and topography for both species, plus secondary roads and rivers for wood frogs. Our results highlight the influence of anthropogenic landscape features within the context of natural features and broad spatial genetic patterns, in turn supporting the premise that while urbanization significantly restricts interpopulation connectivity for wood frogs and spotted salamanders, specific landscape elements have unique effects on these two sympatric species.
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Affiliation(s)
| | - Cynthia S. Loftin
- Maine Cooperative Fish and Wildlife Research UnitU.S. Geological SurveyOronoMEUSA
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21
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Eakin C, Calhoun AJK, Hunter ML. Indicators of wood frog (
Lithobates sylvaticus
) condition in a suburbanizing landscape. Ecosphere 2019. [DOI: 10.1002/ecs2.2789] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Carly Eakin
- Department of Wildlife, Fisheries, and Conservation Biology University of Maine Orono Maine 04469 USA
| | - Aram J. K. Calhoun
- Department of Wildlife, Fisheries, and Conservation Biology University of Maine Orono Maine 04469 USA
| | - Malcolm L. Hunter
- Department of Wildlife, Fisheries, and Conservation Biology University of Maine Orono Maine 04469 USA
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22
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Goldspiel HB, Cohen JB, McGee GG, Gibbs JP. Forest land-use history affects outcomes of habitat augmentation for amphibian conservation. Glob Ecol Conserv 2019. [DOI: 10.1016/j.gecco.2019.e00686] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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23
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Bomske CM, Bickford N. Overwintering Anuran Niche Preferences in a Series of Interconnected Ponds in Northwestern Florida. SOUTHEAST NAT 2019. [DOI: 10.1656/058.018.0207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Caleb M. Bomske
- Department of Horticulture and Natural Resources, Kansas State University, Manhattan, KS 66506
| | - Nate Bickford
- Department of Biology, University of Nebraska, Kearney, NE 68849
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24
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25
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Rowe JC, Duarte A, Pearl CA, McCreary B, Galvan SK, Peterson JT, Adams MJ. Disentangling effects of invasive species and habitat while accounting for observer error in a long‐term amphibian study. Ecosphere 2019. [DOI: 10.1002/ecs2.2674] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Jennifer C. Rowe
- U.S. Geological Survey Forest and Rangeland Ecosystem Science Center 3200 SW Jefferson Way Corvallis Oregon 97331 USA
| | - Adam Duarte
- Oregon Cooperative Fish and Wildlife Research Unit Department of Fisheries and Wildlife Oregon State University 104 Nash Hall Corvallis Oregon 97331 USA
| | - Christopher A. Pearl
- U.S. Geological Survey Forest and Rangeland Ecosystem Science Center 3200 SW Jefferson Way Corvallis Oregon 97331 USA
| | - Brome McCreary
- U.S. Geological Survey Forest and Rangeland Ecosystem Science Center 3200 SW Jefferson Way Corvallis Oregon 97331 USA
| | - Stephanie K. Galvan
- U.S. Geological Survey Forest and Rangeland Ecosystem Science Center 3200 SW Jefferson Way Corvallis Oregon 97331 USA
| | - James T. Peterson
- U.S. Geological Survey Oregon Cooperative Fish and Wildlife Research Unit Department of Fisheries and Wildlife Oregon State University 104 Nash Hall Corvallis Oregon 97331 USA
| | - Michael J. Adams
- U.S. Geological Survey Forest and Rangeland Ecosystem Science Center 3200 SW Jefferson Way Corvallis Oregon 97331 USA
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26
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Sterrett SC, Katz RA, Fields WR, Campbell Grant EH. The contribution of road‐based citizen science to the conservation of pond‐breeding amphibians. J Appl Ecol 2019. [DOI: 10.1111/1365-2664.13330] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sean C. Sterrett
- United States Geological SurveyPatuxent Wildlife Research Center Turners Falls Massachusetts
| | - Rachel A. Katz
- U.S. Fish and Wildlife ServiceNational Wildlife Refuge System Hadley Massachusetts
| | - William R. Fields
- United States Geological SurveyPatuxent Wildlife Research Center Turners Falls Massachusetts
| | - Evan H. Campbell Grant
- United States Geological SurveyPatuxent Wildlife Research Center Turners Falls Massachusetts
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27
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Regnet RA, Loebmann D. Electrocuted! Amphibian deaths caused by electric discharge. BRAZ J BIOL 2019; 79:162-163. [DOI: 10.1590/1519-6984.181449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 08/22/2017] [Indexed: 11/21/2022] Open
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28
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Understanding the Biodiversity Contributions of Small Protected Areas Presents Many Challenges. LAND 2018. [DOI: 10.3390/land7040123] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Small protected areas dominate some databases and are common features of landscapes, yet their accumulated contributions to biodiversity conservation are not well known. Small areas may contribute to global biodiversity conservation through matrix habitat improvement, connectivity, and preservation of localized ecosystems, but there is relatively little literature regarding this. We review one database showing that the average size of nearly 200,000 protected areas in the United States is ~2000 ha and the median is ~20 ha, and that small areas are by far the most frequent. Overall, 95% and 49% of the records are less than the mean (1648 ha) and median (16 ha), respectively. We show that small areas are prevalent features of landscapes, and review literature suggesting how they should be studied and managed at multiple scales. Applying systematic conservation planning in a spatially hierarchical manner has been suggested by others and could help insure that small, local projects contribute to global goals. However, there are data and financial limitations. While some local groups practice ecosystem management and conservation planning, they will likely continue to protect what is “near and dear” and meet site-based goals unless there is better coordination and sharing of resources by larger organizations.
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29
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Reno U, Doyle SR, Momo FR, Regaldo L, Gagneten AM. Effects of glyphosate formulations on the population dynamics of two freshwater cladoceran species. ECOTOXICOLOGY (LONDON, ENGLAND) 2018; 27:784-793. [PMID: 29404864 DOI: 10.1007/s10646-017-1891-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/19/2017] [Indexed: 06/07/2023]
Abstract
The general objective of this work is to experimentally assess the effects of acute glyphosate pollution on two freshwater cladoceran species (Daphnia magna and Ceriodaphnia dubia) and to use this information to predict the population dynamics and the potential for recovery of exposed organisms. Five to six concentrations of four formulations of glyphosate (4-Gly) (Eskoba®, Panzer Gold®, Roundup Ultramax® and Sulfosato Touchdown®) were evaluated in both cladoceran species through acute tests and 15-day recovery tests in order to estimate the population dynamics of microcrustaceans. The endpoints of the recovery test were: survival, growth (number of molts), fecundity, and the intrinsic population growth rate (r). A matrix population model (MPM) was applied to r of the survivor individuals of the acute tests, followed by a Monte Carlo simulation study. Among the 4-Gly tested, Sulfosato Touchdown® was the one that showed higher toxicity, and C. dubia was the most sensitive species. The Monte Carlo simulation study showed an average value of λ always <1 for D. magna, indicating that its populations would not be able to survive under natural environmental conditions after an acute Gly exposure between 0.25 and 35 a.e. mg L-1. The average value of λ for C. dubia was also <1 after exposure to Roundup Ultramax®: 1.30 and 1.20 for 1.21 and 2.5 mg a.e. L-1,respectively. The combined methodology-recovery tests and the later analysis through MPM with a Monte Carlo simulation study-is proposed to integrate key demographic parameters and predict the possible fate of microcrustacean populations after being exposed to acute 4-Gly contamination events.
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Affiliation(s)
- U Reno
- Facultad de Humanidades y Ciencias (UNL), Ciudad Universitaria (3000), Santa Fe, Argentina.
| | - S R Doyle
- Área de Biología y Bioinformática, Instituto de Ciencias, Universidad Nacional de General Sarmiento, Los Polvorines, Buenos Aires, Argentina
| | - F R Momo
- Área de Biología y Bioinformática, Instituto de Ciencias, Universidad Nacional de General Sarmiento, Los Polvorines, Buenos Aires, Argentina
- INEDES, Universidad Nacional de Luján, Luján, Buenos Aires, Argentina
| | - L Regaldo
- Facultad de Humanidades y Ciencias (UNL), Ciudad Universitaria (3000), Santa Fe, Argentina
| | - A M Gagneten
- Facultad de Humanidades y Ciencias (UNL), Ciudad Universitaria (3000), Santa Fe, Argentina
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Amburgey SM, Miller DAW, Campbell Grant EH, Rittenhouse TAG, Benard MF, Richardson JL, Urban MC, Hughson W, Brand AB, Davis CJ, Hardin CR, Paton PWC, Raithel CJ, Relyea RA, Scott AF, Skelly DK, Skidds DE, Smith CK, Werner EE. Range position and climate sensitivity: The structure of among-population demographic responses to climatic variation. GLOBAL CHANGE BIOLOGY 2018; 24:439-454. [PMID: 28833972 DOI: 10.1111/gcb.13817] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 06/26/2017] [Indexed: 05/28/2023]
Abstract
Species' distributions will respond to climate change based on the relationship between local demographic processes and climate and how this relationship varies based on range position. A rarely tested demographic prediction is that populations at the extremes of a species' climate envelope (e.g., populations in areas with the highest mean annual temperature) will be most sensitive to local shifts in climate (i.e., warming). We tested this prediction using a dynamic species distribution model linking demographic rates to variation in temperature and precipitation for wood frogs (Lithobates sylvaticus) in North America. Using long-term monitoring data from 746 populations in 27 study areas, we determined how climatic variation affected population growth rates and how these relationships varied with respect to long-term climate. Some models supported the predicted pattern, with negative effects of extreme summer temperatures in hotter areas and positive effects on recruitment for summer water availability in drier areas. We also found evidence of interacting temperature and precipitation influencing population size, such as extreme heat having less of a negative effect in wetter areas. Other results were contrary to predictions, such as positive effects of summer water availability in wetter parts of the range and positive responses to winter warming especially in milder areas. In general, we found wood frogs were more sensitive to changes in temperature or temperature interacting with precipitation than to changes in precipitation alone. Our results suggest that sensitivity to changes in climate cannot be predicted simply by knowing locations within the species' climate envelope. Many climate processes did not affect population growth rates in the predicted direction based on range position. Processes such as species-interactions, local adaptation, and interactions with the physical landscape likely affect the responses we observed. Our work highlights the need to measure demographic responses to changing climate.
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Affiliation(s)
- Staci M Amburgey
- Department of Ecosystem Sciences and Management, The Pennsylvania State University, University Park, PA, USA
- Intercollege Graduate Ecology Program, The Pennsylvania State University, University Park, PA, USA
| | - David A W Miller
- Department of Ecosystem Sciences and Management, The Pennsylvania State University, University Park, PA, USA
| | - Evan H Campbell Grant
- USGS Patuxent Wildlife Research Center, SO Conte Anadromous Fish Research Center, Turners Falls, MA, USA
| | - Tracy A G Rittenhouse
- Department of Natural Resources and the Environment, University of Connecticut, Storrs, CT, USA
| | - Michael F Benard
- Department of Biology, Case Western Reserve University, Cleveland, OH, USA
| | | | - Mark C Urban
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA
| | | | - Adrianne B Brand
- USGS Patuxent Wildlife Research Center, SO Conte Anadromous Fish Research Center, Turners Falls, MA, USA
| | - Christopher J Davis
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Carmen R Hardin
- Forestry Division, Wisconsin Department of Natural Resources, Madison, WI, USA
| | - Peter W C Paton
- Department of Natural Resources Science, University of Rhode Island, Kingston, RI, USA
| | - Christopher J Raithel
- Division of Fish and Wildlife, Rhode Island Department of Environmental Management, West Kingston, RI, USA
| | - Rick A Relyea
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - A Floyd Scott
- Department of Biology, Austin Peay State University, Clarksville, TN, USA
| | - David K Skelly
- School of Forestry and Environmental Studies, Yale University, New Haven, CT, USA
| | - Dennis E Skidds
- Northeast Coastal and Barrier Network, National Parks Service, Kingston, RI, USA
| | - Charles K Smith
- Department of Biology, High Point University, High Point, NC, USA
| | - Earl E Werner
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
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31
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Lau A, Karraker NE, Dudgeon D. Does forest extent affect salamander survival? Evidence from a long-term demographic study of a tropical newt. Ecol Evol 2017; 7:10963-10973. [PMID: 29299273 PMCID: PMC5743689 DOI: 10.1002/ece3.3623] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 10/11/2017] [Accepted: 10/16/2017] [Indexed: 12/03/2022] Open
Abstract
Forest loss has been associated with reduced survival in many vertebrates, and previous research on amphibians has mostly focused on effects at early life stages. Paramesotriton hongkongensis is a tropical newt that breeds in streams but spends up to 10 months per year in terrestrial habitats. Populations are threatened by habitat degradation and collection for the pet trade, but the cryptic terrestrial lifestyle of this newt has limited our understanding of its population ecology, which inhibits development of a species-specific conservation plan. We conducted an eight-year (2007-2014) mark-recapture study on four P. hongkongensis populations in Hong Kong and used these data to evaluate relationships between forest cover, body size, and rainfall on survival and to estimate population sizes. Hong Kong has been subjected to repeated historic territory-wide deforestation, and thus, we wanted to determine whether there was a link between forest extent as a proxy of habitat quality and newt demography. Annual survival was positively associated with forest cover within core habitat of all populations and negatively related to body size. Mean annual survival (~60%) was similar to that of other stream-dwelling amphibians, but varied among years and declined substantially in 2012-2013, perhaps due to illegal collection. Despite the link between forest extent and survival, population sizes declined at the most forested site by 40% and increased by 104% and 134% at two others. Forest protection and consequential secondary succession during recent decades in Hong Kong may have been responsible for persistence of P. hongkongensis populations.
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Affiliation(s)
- Anthony Lau
- School of Biological SciencesThe University of Hong KongHong Kong SARChina
- Ocean Park Conservation Foundation Hong KongAberdeen, Hong Kong SARChina
| | - Nancy E. Karraker
- Department of Natural Resources SciencesUniversity of Rhode IslandKingstonRIUSA
| | - David Dudgeon
- School of Biological SciencesThe University of Hong KongHong Kong SARChina
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32
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Westgate MJ, MacGregor C, Scheele BC, Driscoll DA, Lindenmayer DB. Effects of time since fire on frog occurrence are altered by isolation, vegetation and fire frequency gradients. DIVERS DISTRIB 2017. [DOI: 10.1111/ddi.12659] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Martin J. Westgate
- Fenner School of Environment and Society The Australian National University Canberra ACT Australia
| | - Christopher MacGregor
- Fenner School of Environment and Society The Australian National University Canberra ACT Australia
- Long‐term Ecological Research Network Fenner School of Environment and Society The Australian National University Canberra ACT Australia
| | - Ben C. Scheele
- Fenner School of Environment and Society The Australian National University Canberra ACT Australia
- National Environmental Science Programme Threatened Species Recovery Hub The Australian National University Canberra ACT Australia
| | - Don A. Driscoll
- Fenner School of Environment and Society The Australian National University Canberra ACT Australia
- School of Life and Environmental Sciences Centre for Intregrative Ecology Deakin University Burwood Vic. Australia
| | - David B. Lindenmayer
- Fenner School of Environment and Society The Australian National University Canberra ACT Australia
- Long‐term Ecological Research Network Fenner School of Environment and Society The Australian National University Canberra ACT Australia
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33
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Pintar MR, Resetarits WJ. Persistence of an egg mass polymorphism in Ambystoma maculatum: differential performance under high and low nutrients. Ecology 2017; 98:1349-1360. [PMID: 28247910 DOI: 10.1002/ecy.1789] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 01/14/2017] [Accepted: 02/16/2017] [Indexed: 11/09/2022]
Abstract
Polymorphisms play critical roles in allowing organisms to adapt to novel environments while enabling ecological speciation under divergent selection. Ambystoma maculatum, the spotted salamander, exhibits a unique polymorphism in the structure and appearance of its egg masses with two common morphs, white and clear. Amphibian egg jelly layers mediate interactions between embryos and the environment and are more responsive to ecological pressures of natural selection than other egg coat components. The A. maculatum egg mass polymorphism was hypothesized to be adaptive with regard to varying dissolved nutrient levels in ponds. We conducted two mesocosm experiments, collected field data, and constructed a population projection model to determine how dissolved nutrient levels affect embryonic and larval development and relate to the distribution of the morphs in natural ponds. We found that upon hatching there was an interaction between nutrient level and egg mass morph wherein individuals from white morphs were larger in low nutrient habitats. This interaction persisted throughout the larval stage, and along with the higher abundance of white morphs in ponds with low conductivity, we demonstrate that the white morph is advantageous in low nutrient environments. Our findings provide evidence for the role of environmental heterogeneity in enabling the persistence of a structural egg mass polymorphism, with maintenance occurring across multiple scales and persistence across its range. This indicates that polymorphisms can maximize performance in heterogeneous environments, while persisting over long timescales without leading to sympatric speciation.
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Affiliation(s)
- Matthew R Pintar
- Department of Biology, University of Mississippi, University, Mississippi, 38677, USA
| | - William J Resetarits
- Department of Biology, University of Mississippi, University, Mississippi, 38677, USA
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34
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Holzer KA, Bayers RP, Nguyen TT, Lawler SP. Habitat value of cities and rice paddies for amphibians in rapidly urbanizing Vietnam. JOURNAL OF URBAN ECOLOGY 2017. [DOI: 10.1093/jue/juw007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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35
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Van Dyke F, Berthel A, Harju SM, Lamb RL, Thompson D, Ryan J, Pyne E, Dreyer G. Amphibians in forest pools: Does habitat clustering affect community diversity and dynamics? Ecosphere 2017. [DOI: 10.1002/ecs2.1671] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Fred Van Dyke
- Au Sable Institute; 7526 Sunset Trail NE Mancelona Michigan 49659 USA
| | - Allison Berthel
- Department of Biology; Wheaton College; Wheaton Illinois 60187 USA
| | | | | | - Dan Thompson
- DuPage Forest Preserve; 3S580 Naperville Road Wheaton Illinois 60189 USA
| | - Julia Ryan
- Department of Biology; Wheaton College; Wheaton Illinois 60187 USA
| | - Erin Pyne
- Department of Biology; Wheaton College; Wheaton Illinois 60187 USA
| | - Gwyneth Dreyer
- Department of Biology; Wheaton College; Wheaton Illinois 60187 USA
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36
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Buffer-Mediated Effects of Clearcutting on In-Pool Amphibian Productivity: Can Aquatic Processes Compensate for Terrestrial Habitat Disturbance? FORESTS 2016. [DOI: 10.3390/f8010010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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37
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Guerra C, Aráoz E. Amphibian malformations and body condition across an agricultural landscape of northwest Argentina. DISEASES OF AQUATIC ORGANISMS 2016; 121:105-116. [PMID: 27667808 DOI: 10.3354/dao03048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Agricultural landscapes support large amphibian populations because they provide habitat for many species, although agriculture affects amphibians through various mechanisms. Pollution with agrochemicals is the major threat to amphibian populations after habitat loss, as chemicals alter the ecophysiology of amphibians, putting their health and survival at risk. We aimed to assess the effect of different environments, sites, width of forest buffers and sampling years on the health of amphibians, which was estimated through the prevalence of malformations and body condition. During 3 yr of pitfall trapping, we captured 4491 amphibians. The prevalence of malformations was higher in the croplands than in the forests, while the body condition was better within forests. The prevalence of malformations was higher in the narrower forest site than in the wider forest site. The prevalence of malformations and the body condition were higher in the third year. The prevalence of malformations differed by species. We found 11 types of malformation, which mainly affected limbs and were unilateral or bilaterally asymmetrical. Our results showed that the prevalence of malformations and body condition reflect different aspects of the health of amphibians and that forest individuals are healthier than those from croplands. The results also highlight the importance of spatial configuration besides the conservation of natural habitats to preserve healthy amphibians in agricultural landscapes. The types of malformation that we found suggest that agrochemicals could be an important cause of malformations.
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Affiliation(s)
- Cecilia Guerra
- Instituto de Herpetología, Fundación Miguel Lillo, Miguel Lillo 251, San Miguel de Tucumán (4000), Tucumán, Argentina
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38
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Bancroft BA, Lawler JJ, Schumaker NH. Weighing the relative potential impacts of climate change and land-use change on an endangered bird. Ecol Evol 2016; 6:4468-77. [PMID: 27386089 PMCID: PMC4930994 DOI: 10.1002/ece3.2204] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 04/18/2016] [Accepted: 05/04/2016] [Indexed: 11/18/2022] Open
Abstract
Climate change and land‐use change are projected to be the two greatest drivers of biodiversity loss over the coming century. Land‐use change has resulted in extensive habitat loss for many species. Likewise, climate change has affected many species resulting in range shifts, changes in phenology, and altered interactions. We used a spatially explicit, individual‐based model to explore the effects of land‐use change and climate change on a population of the endangered Red‐cockaded Woodpecker (RCW; Picoides borealis). We modeled the effects of land‐use change using multiple scenarios representing different spatial arrangements of new training areas for troops across Fort Benning. We used projected climate‐driven changes in habitat and changes in reproductive output to explore the potential effects of climate change. We summarized potential changes in habitat based on the output of the dynamic vegetation model LPJ‐GUESS, run for multiple climate change scenarios through the year 2100. We projected potential changes in reproduction based on an empirical relationship between spring precipitation and the mean number of successful fledglings produced per nest attempt. As modeled in our study, climate change had virtually no effect on the RCW population. Conversely, simulated effects of land‐use change resulted in the loss of up to 28 breeding pairs by 2100. However, the simulated impacts of development depended on where the development occurred and could be completely avoided if the new training areas were placed in poor‐quality habitat. Our results demonstrate the flexibility inherent in many systems that allows seemingly incompatible human land uses, such as development, and conservation actions to exist side by side.
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Affiliation(s)
- Betsy A. Bancroft
- School of Environmental and Forest SciencesUniversity of WashingtonSeattleWashington
- Present address: Departments of Biology and Environmental StudiesGonzaga UniversitySpokaneWashington
| | - Joshua J. Lawler
- School of Environmental and Forest SciencesUniversity of WashingtonSeattleWashington
| | - Nathan H. Schumaker
- Western DivisionUnited States Environmental Protection AgencyCorvallisOregon
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39
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Earl JE, Chaney JC, Sutton WB, Lillard CE, Kouba AJ, Langhorne C, Krebs J, Wilkes RP, Hill RD, Miller DL, Gray MJ. Ranavirus could facilitate local extinction of rare amphibian species. Oecologia 2016; 182:611-23. [DOI: 10.1007/s00442-016-3682-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 06/14/2016] [Indexed: 11/30/2022]
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40
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Semlitsch RD, Anderson TL. Structure and Dynamics of Spotted Salamander (Ambystoma maculatum) Populations in Missouri. HERPETOLOGICA 2016. [DOI: 10.1655/herpetologica-d-15-00049] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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41
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Anderson T, Linares C, Dodson K, Semlitsch R. Variability in functional response curves among larval salamanders: comparisons across species and size classes. CAN J ZOOL 2016. [DOI: 10.1139/cjz-2015-0149] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Predator species and body size represent critical factors that have differential effects on prey populations, as well as overall community structure. However, investigations of how morphologically-similar predator species, simultaneous to variation in predator body size, influence lower trophic levels are infrequently performed. We tested whether predator species and body size influenced the functional response curve of three larval ambystomatid salamanders (Ringed Salamander, Ambystoma annulatum Cope, 1886; Spotted Salamander, Ambystoma maculatum (Shaw, 1802); Marbled Salamander, Ambystoma opacum (Gravenhorst, 1807)) while eating congeneric prey. We combined larval salamanders of varying body sizes with up to six prey densities within experimental microcosms. We tested for the shape of the functional response curve and obtained parameter estimates for attack rate and handling time for each predator size – species combination. We found variability among both species and size classes, with a combination of type I and type II functional response curves. Large size classes of predators had higher attack rates than smaller size classes, but equivalently-sized larvae of different species exhibited differences in attack rates and handling time. Our study shows that predation risk varies depending on the size structure and diversity of predators present in a food web, and that grouping predators by either species or size class may reduce the ability to predict changes in community structure resulting from such interactions.
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Affiliation(s)
- T.L. Anderson
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
| | - C. Linares
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
| | - K.N. Dodson
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
| | - R.D. Semlitsch
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211-7400, USA
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Harper EB, Patrick DA, Gibbs JP. Impact of forestry practices at a landscape scale on the dynamics of amphibian populations. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2015; 25:2271-2284. [PMID: 26910954 DOI: 10.1890/14-0962.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Forest loss is a primary cause of worldwide amphibian decline. Timber harvesting in the United States has caused dramatic changes in quality and extent of forest ecosystems, and intensive forest management still occurs. Although numerous studies have documented substantial reductions in amphibian densities related to timber harvest, subsequent extinctions are rare. To better understand the population dynamics that have allowed so many amphibian species to persist in the face of widespread forest disturbance, we developed spatially explicit metapopulation models for four forest-dependent amphibian species (Lithobates sylvaticus, Ambystoma opacum, A. talpoideum, and A. maculatum) that incorporated demographic and habitat selection data derived from experiments conducted as part of the Land Use Effects on Amphibian Populations Project (LEAP). We projected local and landscape-scale population persistence under 108 different forestry practice scenarios, varying treatment (partial cut, clear-cut with coarse woody debris [CWD] removed, and clearcut with CWD retained), cut patch size (1, 10, or 50 ha), total area cut (10, 20, or 30%), and initial amphibian population size (5, 50, or 500 adult females per local breeding population). Under these scenarios, landscape-scale extinction was highly unlikely, occurring in < 1% of model runs and for only 2 of the 4 species, because landscape-scale populations were able to persist via dispersal even despite frequent local extinctions. Yet for all species, population sizes were reduced to -50% in all clear-cut scenarios, regardless of the size of harvested patches. These findings suggest that debate over timber harvesting on pool-breeding amphibian populations in the United States should focus not on questions of landscape-scale extinction but on the ecological consequences of dramatic reductions in amphibian biomass, including changes in trophic interactions, nutrient cycling, and energy transfer. Additionally, we conclude that amphibian declines and extinctions are far more likely to occur as a result of permanent habitat loss resulting from development than from the temporary degradation of habitat caused by current forestry practices.
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Veysey Powell JS, Babbitt KJ. Despite Buffers, Experimental Forest Clearcuts Impact Amphibian Body Size and Biomass. PLoS One 2015; 10:e0143505. [PMID: 26600386 PMCID: PMC4658104 DOI: 10.1371/journal.pone.0143505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/05/2015] [Indexed: 11/19/2022] Open
Abstract
Forest buffers are a primary tool used to protect wetland-dependent wildlife. Though implemented widely, buffer efficacy is untested for most amphibian species. Consequently, it remains unclear whether buffers are sufficient for maintaining amphibian populations and if so, how wide buffers should be. We present evidence from a six-year, landscape-scale experiment testing the impacts of clearcutting, buffer width, and hydroperiod on body size and condition and biomass of breeding adults for two amphibian species at 11 vernal pools in the northeastern United States. We randomly assigned treatments (i.e., reference, 100m buffer, 30m buffer) across pools, clearcut to create buffers, and captured all spotted salamanders and wood frogs. Clearcuts strongly and negatively impacted size, condition, and biomass, but wider buffers mitigated effect magnitude and duration. Among recaptured individuals, for example, 30m-treatment salamanders were predicted to be about 9.5 mm shorter than, while 100m-treatment salamanders did not differ in length from, reference-treatment salamanders. Similarly, among recaptured frogs, mean length in the 30m treatment was predicted to decrease by about 1 mm/year, while in the 100m and reference treatments, length was time-invariant. Some, but not all, metrics recovered with time. For example, female new-captured and recaptured salamanders were predicted, respectively and on average, to weigh 4.5 and 7 g less in the 30m versus reference treatment right after the cut. While recaptured-female mass was predicted to recover by 9.5 years post-cut, new-captured-female mass did not recover. Hydroperiod was an important mediator: in the 100m treatment, cutting predominately affected pools that were stressed hydrologically. Overall, salamanders and female frogs were impacted more than male frogs. Our results highlight the importance of individualized metrics like body size, which can reveal sublethal effects and illuminate mechanisms by which habitat disturbance impacts wildlife populations. Individualized metrics thus provide critical insights that complement species occurrence and abundance-based population assessments.
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Affiliation(s)
- Jessica S. Veysey Powell
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire, United States of America
| | - Kimberly J. Babbitt
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire, United States of America
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Anderson TL, Ousterhout BH, Peterman WE, Drake DL, Semlitsch RD. Life history differences influence the impacts of drought on two pond-breeding salamanders. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2015; 25:1896-1910. [PMID: 26591455 DOI: 10.1890/14-2096.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Drought is a strong density-independent environmental filter that contributes to population regulation and other ecological processes. Not all species respond similarly to drought, and the overall impacts can vary depending on life histories. Such differences can necessitate management strategies that incorporate information on individual species to maximize conservation success. We report the effects of a short-term drought on occupancy and reproductive success of two pond-breeding salamanders that differ in breeding phenology (fall vs. spring breeder) across an active military base landscape in Missouri, USA: We surveyed ~200 ponds for the presence of eggs, larvae, and metamorphs from 2011 to 2013. This period coincided with before, during, and after a severe drought that occurred in 2012. The two species showed contrasting responses to drought, where high reproductive failure (34% of ponds) was observed for the spring breeder during a single drought year. Alternatively, the fall breeder only showed a cumulative 8% failure over two years. The number of breeding ponds available for use in the fall decreased during the drought due to pond drying and/or a lack of re-filling. Estimates of occupancy probability declined for the fall-breeding salamander between 2012 and 2013, whereas occupancy probability estimates of the spring breeder increased post-drought. The presence of fish, hydroperiod, the amount of forest cover surrounding ponds, and canopy cover were all found to affect estimates of occupancy probabilities of each species. Pond clustering (distance to nearest pond and the number of ponds within close proximity), hydroperiod, forest cover, and canopy cover influenced both estimates of colonization and extinction probabilities. Our results show life history variation can be important in determining the relative susceptibility of a species to drought conditions, and that sympatric species experiencing the same environmental conditions can respond differently. Consideration of the spatial network and configuration of habitat patches that act as refuges under extreme environmental conditions will improve conservation efforts, such as the placement of permanent ponds for aquatic organisms. A better awareness of species-specific tolerances to environmental filters such as drought can lead to improved management recommendations to conserve and promote habitat for a greater diversity of species across landscapes of spatially connected populations.
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Veysey Powell JS, Babbitt KJ. An Experimental Test of Buffer Utility as a Technique for Managing Pool-Breeding Amphibians. PLoS One 2015; 10:e0133642. [PMID: 26196129 PMCID: PMC4510551 DOI: 10.1371/journal.pone.0133642] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 06/30/2015] [Indexed: 11/18/2022] Open
Abstract
Vegetated buffers are used extensively to manage wetland-dependent wildlife. Despite widespread application, buffer utility has not been experimentally validated for most species. To address this gap, we conducted a six-year, landscape-scale experiment, testing how buffers of different widths affect the demographic structure of two amphibian species at 11 ephemeral pools in a working forest of the northeastern U.S. We randomly assigned each pool to one of three treatments (i.e., reference, 100m buffer, 30m buffer) and clearcut to create buffers. We captured all spotted salamanders and wood frogs breeding in each pool and examined the impacts of treatment and hydroperiod on breeding-population abundance, sex ratio, and recapture rate. The negative effects of clearcutting tended to increase as forest-buffer width decreased and be strongest for salamanders and when other stressors were present (e.g., at short-hydroperiod pools). Recapture rates were reduced in the 30m, but not 100m, treatment. Throughout the experiment for frogs, and during the first year post-cut for salamanders, the predicted mean proportion of recaptured adults in the 30m treatment was only 62% and 40%, respectively, of that in the reference treatment. Frog sex ratio and abundance did not differ across treatments, but salamander sex ratios were increasingly male-biased in both cut treatments. By the final year, there were on average, only about 40% and 65% as many females predicted in the 100m and 30m treatments, respectively, compared to the first year. Breeding salamanders at short-hydroperiod pools were about 10% as abundant in the 100m versus reference treatment. Our study demonstrates that buffers partially mitigate the impacts of habitat disturbance on wetland-dependent amphibians, but buffer width and hydroperiod critically mediate that process. We provide the first experimental evidence showing that 30-m-wide buffers may be insufficient for maintaining resilient breeding populations of pool-dependent amphibians, at least during the first six years post-disturbance.
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Affiliation(s)
- Jessica S. Veysey Powell
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire, United States of America
| | - Kimberly J. Babbitt
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire, United States of America
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Semlitsch RD, Drake DL. Structure and Dynamics ofLithobates sylvaticus(Wood Frog) at the Periphery of Its Range in Missouri. SOUTHEAST NAT 2015. [DOI: 10.1656/058.014.0218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Coster SS, Babbitt KJ, Cooper A, Kovach AI. Limited influence of local and landscape factors on finescale gene flow in two pond-breeding amphibians. Mol Ecol 2015; 24:742-58. [DOI: 10.1111/mec.13062] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/12/2014] [Accepted: 01/02/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Stephanie S. Coster
- Department of Natural Resources and the Environment; University of New Hampshire; 114 James Hall Durham NH 03824 USA
| | - Kimberly J. Babbitt
- Department of Natural Resources and the Environment; University of New Hampshire; 114 James Hall Durham NH 03824 USA
| | - Andrew Cooper
- School of Resource and Environmental Management; Simon Fraser University; 8888 University Drive Burnaby BC V5A 1S6 Canada
| | - Adrienne I. Kovach
- Department of Natural Resources and the Environment; University of New Hampshire; 114 James Hall Durham NH 03824 USA
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Lenhardt PP, Brühl CA, Berger G. Temporal coincidence of amphibian migration and pesticide applications on arable fields in spring. Basic Appl Ecol 2015. [DOI: 10.1016/j.baae.2014.10.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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The Importance of Maintaining Upland Forest Habitat Surrounding Salamander Breeding Ponds: Case Study of the Eastern Tiger Salamander in New York, USA. FORESTS 2014. [DOI: 10.3390/f5123070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Earl JE, Gray MJ. Introduction of ranavirus to isolated wood frog populations could cause local extinction. ECOHEALTH 2014; 11:581-592. [PMID: 24962849 DOI: 10.1007/s10393-014-0950-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 02/25/2014] [Accepted: 03/31/2014] [Indexed: 06/03/2023]
Abstract
Amphibian declines and extinction have been attributed to many causes, including disease such as chytridiomycosis. Other pathogens may also contribute to declines, with ranavirus as the most likely candidate given reoccurring die-offs observed in the wild. We were interested in whether it is possible for ranavirus to cause extinction of a local, closed population of amphibians. We used susceptibility data from experimental challenges on different life stages combined with estimates of demographic parameters from a natural population to predict the likelihood of extinction using a stage-structured population model for wood frogs (Lithobates sylvaticus). Extinction was most likely when the larval or metamorph stage was exposed under frequent intervals in smaller populations. Extinction never occurred when only the egg stage was exposed to ranavirus. Under the worst-case scenario, extinction could occur in as quickly as 5 years with exposure every year and 25-44 years with exposure every 2 years. In natural wood frog populations, die-offs typically occur in the larval stage and can reoccur in subsequent years, indicating that our simulations represent possible scenarios. Additionally, wood frog populations are particularly sensitive to changes in survival during the pre-metamorphic stages when ranavirus tends to be most pathogenic. Our results suggest that ranavirus could contribute to amphibian species declines, especially for species that are very susceptible to ranavirus with closed populations. We recommend that ranavirus be considered in risk analyses for amphibian species.
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Affiliation(s)
- Julia E Earl
- National Institute for Mathematical and Biological Synthesis, University of Tennessee, Knoxville, TN, 37996, USA,
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