1
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Species loss and nitrogen pollution alter litter decomposition dynamics in coastal salt marshes. Oecologia 2022; 200:479-490. [DOI: 10.1007/s00442-022-05273-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 10/04/2022] [Indexed: 11/06/2022]
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2
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Elliott Smith EA, Harrod C, Docmac F, Newsome SD. Intraspecific variation and energy channel coupling within a Chilean kelp forest. Ecology 2021; 102:e03198. [PMID: 33009678 DOI: 10.1002/ecy.3198] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 07/10/2020] [Accepted: 08/07/2020] [Indexed: 12/21/2022]
Abstract
The widespread importance of variable types of primary production, or energy channels, to consumer communities has become increasingly apparent. However, the mechanisms underlying this "multichannel" feeding remain poorly understood, especially for aquatic ecosystems that pose unique logistical constraints given the diversity of potential energy channels. Here, we use bulk tissue isotopic analysis along with carbon isotope (δ13 C) analysis of individual amino acids to characterize the relative contribution of pelagic and benthic energy sources to a kelp forest consumer community in northern Chile. We measured bulk tissue δ13 C and δ15 N for >120 samples; of these we analyzed δ13 C values of six essential amino acids (EAA) from nine primary producer groups (n = 41) and 11 representative nearshore consumer taxa (n = 56). Using EAA δ13 C data, we employed linear discriminant analysis (LDA) to assess how distinct EAA δ13 C values were between local pelagic (phytoplankton/particulate organic matter), and benthic (kelps, red algae, and green algae) endmembers. With this model, we were able to correctly classify nearly 90% of producer samples to their original groupings, a significant improvement on traditional bulk isotopic analysis. With this EAA isotopic library, we then generated probability distributions for the most important sources of production for each individual consumer and species using a bootstrap-resampling LDA approach. We found evidence for multichannel feeding within the community at the species level. Invertebrates tended to focus on either pelagic or benthic energy, deriving 13-67% of their EAA from pelagic sources. In contrast, mobile (fish) taxa at higher trophic levels used more equal proportions of each channel, ranging from 19% to 47% pelagically derived energy. Within a taxon, multichannel feeding was a result of specialization among individuals in energy channel usage, with 37 of 56 individual consumers estimated to derive >80% of their EAA from a single channel. Our study reveals how a cutting-edge isotopic technique can characterize the dynamics of energy flow in coastal food webs, a topic that has historically been difficult to address. More broadly, our work provides a mechanism as to how multichannel feeding may occur in nearshore communities, and we suggest this pattern be investigated in additional ecosystems.
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Affiliation(s)
- Emma A Elliott Smith
- Department of Anthropology, National Museum of Natural History, Smithsonian Institution, 10th St. & Constitution Ave. NW, Washington, D.C., 20560, USA
- Department of Biology, University of New Mexico, 219 Yale Blvd NE, Albuquerque, New Mexico, 87131-0001, USA
| | - Chris Harrod
- Instituto de Ciencias Naturales Alexander von Humboldt, Universidad de Antofagasta, Avenida Angamos 601, Antofagasta, Chile
- Universidad de Antofagasta Stable Isotope Facility (UASIF), Universidad de Antofagasta, Avenida Angamos 601, Antofagasta, Chile
- Núcleo Milenio Salmónidos Invasores (INVASAL), Concepción, Chile
| | - Felipe Docmac
- Instituto de Ciencias Naturales Alexander von Humboldt, Universidad de Antofagasta, Avenida Angamos 601, Antofagasta, Chile
- Universidad de Antofagasta Stable Isotope Facility (UASIF), Universidad de Antofagasta, Avenida Angamos 601, Antofagasta, Chile
| | - Seth D Newsome
- Department of Biology, University of New Mexico, 219 Yale Blvd NE, Albuquerque, New Mexico, 87131-0001, USA
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3
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Wimp GM, Lewis D, Murphy SM. Prey identity but not prey quality affects spider performance. CURRENT RESEARCH IN INSECT SCIENCE 2021; 1:100013. [PMID: 36003602 PMCID: PMC9387502 DOI: 10.1016/j.cris.2021.100013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 03/11/2021] [Accepted: 03/15/2021] [Indexed: 12/01/2022]
Abstract
Prey identity affected the survival and body mass of a generalist spider predator. Trophic level of the prey did not affect spider survival and body mass. Prey identity and cordgrass quality had an interactive effect on spider body mass. Greater spider body mass led to greater egg production. In a literature review, female spider fitness increased with greater body size.
Increasing host plant quality affects higher trophic level predators, but whether such changes are simply a result of prey density or are also affected by changes in prey quality remain uncertain. Moreover, whether changes in prey quality affect measures of predator performance is understudied. Using a combination of field and greenhouse mesocosm experiments, we demonstrate that the survival and body size of a hunting spider (Pardosa littoralis Araneae: Lycosidae) is affected more by prey species identity than the trophic level of the prey. Furthermore, increasing host plant quality does not necessarily propagate through the food web by altering prey quality. While changes in plant quality affected spider body mass, they did so in opposite ways for spiders feeding on Prokelisia (Hemiptera: Delphacodes) herbivores relative to Tytthus (Hemiptera: Miridae) egg predators, and had no impact on spider body mass for two additional species of intraguild prey. These changes in body mass were important because greater body mass increased spider egg production. To examine the generality of this pattern, we reviewed the literature and found a consistent positive relationship between female body size and egg production for Pardosa species, indicating that body size is a reliable proxy for fitness. While many studies emphasize the importance of nitrogen to arthropod diets, this focus may be driven largely by our understanding of herbivore diets rather than predator diets. Thus, the positive impact of host plant quality on higher trophic level predators appears to be driven more by altering prey composition, density, and availability rather than simply providing predators with more nutritious prey.
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Affiliation(s)
- Gina M. Wimp
- Department of Biology, Georgetown University, Washington, DC, USA
- Corresponding author.
| | - Danny Lewis
- Department of Biology, Georgetown University, Washington, DC, USA
| | - Shannon M. Murphy
- Department of Biological Sciences, University of Denver, Denver, CO, USA
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Karasawa S. Sphaerillo boninensis Nunomura, 1990 (Crustacea, Isopoda, Oniscidea) is a junior synonym of a pantropical species, Venezillo parvus (Budde-Lund, 1885). Zookeys 2020; 923:1-14. [PMID: 32292267 PMCID: PMC7142170 DOI: 10.3897/zookeys.923.26018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 02/14/2020] [Indexed: 11/12/2022] Open
Abstract
Re-examination of the holotype and paratype of Sphaerillo boninensis Nunomura, 1990 from Chichijima Island of the Ogasawara archipelago, which is registered as a UNESCO World Heritage Site, indicates that this species is a junior synonym of a pantropical species, Venezillo parvus (Budde-Lund, 1885).
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Affiliation(s)
- Shigenori Karasawa
- Department of Life and Environmental Agricultural Sciences, Faculty of Agriculture, Tottori University, 4-101 Koyama-machi Minami, Tottori 680-8553, Japan Tottori University Tottori Japan
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5
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Predator population size structure alters consumption of prey from epigeic and grazing food webs. Oecologia 2020; 192:791-799. [PMID: 32086561 DOI: 10.1007/s00442-020-04619-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Accepted: 02/07/2020] [Indexed: 10/24/2022]
Abstract
Numerous studies have found that predators can suppress prey densities and thereby impact important ecosystem processes such as plant productivity and decomposition. However, prey suppression by spiders can be highly variable. Unlike predators that feed on prey within a single energy channel, spiders often consume prey from asynchronous energy channels, such as grazing (live plant) and epigeic (soil surface) channels. Spiders undergo few life cycle changes and thus appear to be ideally suited to link energy channels, but ontogenetic diet shifts in spiders have received little attention. For example, spider use of different food channels may be highly specialized in different life stages and thus a species may be a multichannel omnivore only when we consider all life stages. Using stable isotopes, we investigated whether wolf spider (Pardosa littoralis, henceforth Pardosa) prey consumption is driven by changes in spider size. Small spiders obtained > 80% of their prey from the epigeic channel, whereas larger spiders used grazing and epigeic prey almost equally. Changes in prey consumption were not driven by changes in prey density, but by changes in prey use by different spider size classes. Thus, because the population size structure of Pardosa changes dramatically over the growing season, changes in spider size may have important implications for the strength of trophic cascades. Our research demonstrates that life history can be an important component of predator diet, which may in turn affect community- and ecosystem-level processes.
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Wimp GM, Lewis D, Murphy SM. Impacts of Nutrient Subsidies on Salt Marsh Arthropod Food Webs: A Latitudinal Survey. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00350] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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7
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Wimp GM, Ries L, Lewis D, Murphy SM. Habitat edge responses of generalist predators are predicted by prey and structural resources. Ecology 2019; 100:e02662. [PMID: 31013545 DOI: 10.1002/ecy.2662] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 11/30/2018] [Accepted: 01/02/2019] [Indexed: 11/09/2022]
Abstract
Generalist predators are thought to be less vulnerable to habitat fragmentation because they use diverse resources across larger spatial scales than specialist predators. Thus, it has been suggested that generalist predators may respond positively to habitat edges or demonstrate no edge response, because they can potentially use prey resources equally well on both sides of the habitat edge. However, most predictions about generalist predator responses to the habitat edge are based solely on prey resources, without consideration of other potential drivers. For instance, structural resources are essential for some species to build webs to capture prey or to avoid intraguild predation and cannibalism. In this study, we used both prey and structural resources to predict the response of four predator functional groups (hunting spiders, web-building spiders, aerial predators, and epigeic predators that feed on the detrital/algal food web) to a habitat edge between two salt-marsh grasses (Spartina alterniflora and Spartina patens). We found that generalist predators largely demonstrated negative responses to the habitat edge and had distinct habitat associations. Positive edge responses were only observed in one functional group (hunting spiders), and this pattern was driven by the two most abundant species. Negative responses to the habitat edge were more common among taxa and were better explained by structural resources rather than prey resources in the two habitats. Although it is generally acknowledged that specialists decline in fragmented habitats, generalists are thought to be more resilient. However, our research demonstrates that even generalists have habitat structural or food resource requirements that may limit their resilience to habitat loss and fragmentation.
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Affiliation(s)
- Gina M Wimp
- Biology Department, Georgetown University, Washington, D.C., 20057, USA
| | - Leslie Ries
- Biology Department, Georgetown University, Washington, D.C., 20057, USA
| | - Danny Lewis
- Biology Department, Georgetown University, Washington, D.C., 20057, USA
| | - Shannon M Murphy
- Department of Biological Sciences, University of Denver, Denver, Colorado, 80208, USA
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8
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Vidal MC, Sendoya SF, Yamaguchi LF, Kato MJ, Oliveira RS, Oliveira PS. Natural History of a Sit-and-Wait Dipteran Predator That Uses Extrafloral Nectar as Prey Attractant. ENVIRONMENTAL ENTOMOLOGY 2018; 47:1165-1172. [PMID: 30007344 DOI: 10.1093/ee/nvy097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Indexed: 06/08/2023]
Abstract
Sit-and-wait predators use different strategies to encounter potential prey. Rhinoleucophenga myrmecophaga Vidal et (Vidal et Vilela; Diptera: Drosophilidae) larvae build sticky shelters on top of extrafloral nectaries (EFNs) of Qualea grandiflora Mart (Vochysiaceae), a common plant in the Brazilian cerrado savanna. Although larval shelters block the EFNs, nectar production is not obstructed and is used by the larvae to attract and trap nectar-gathering ants that are eventually eaten by the dipteran. Here we describe the natural history of R. myrmecophaga, its infestation pattern in Q. grandiflora, the ant assemblage at EFNs, and the insects used as prey. We use stable isotope composition (δ13C and δ15N) of R. myrmecophaga and potential food sources to infer its diet, and perform chemical analyses of the droplets found at shelter openings to determine whether nectar is used as a prey attractant. We found that Rhinoleucophenga larvae occur on the majority of Qualea plants and occupy active EFNs mainly in the rainy season. The two most frequent visiting species were also the most common insects found trapped at larval shelters. The stable isotope analyses confirmed that ants are the main food sources of R. myrmecophaga. Chemical analyses and field observations revealed that Rhinoleucophenga larvae use extrafloral nectar to attract prey to their shelters by pushing this liquid to the shelter opening where it forms a droplet. This is a rare case of sit-and-wait predator exploiting an ant-plant mutualism through the use of the very food reward produced by the plant to attract and capture potential ant mutualists.
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Affiliation(s)
- Mayra C Vidal
- Graduate Program in Ecology, Instituto de Biologia, Universidade Estadual de Campinas, Campinas SP, Brazil
- Department of Biological Sciences, Graduate Program in Ecology and Evolution, University of Denver, Denver, CO
| | - Sebastián F Sendoya
- Department of Zoology, Ecology and Genetics, Universidade Federal de Pelotas, Pelotas RS, Brazil
| | - Lydia F Yamaguchi
- Laboratory of Chemistry of Natural Products, Chemistry Institute, Universidade de São Paulo, São Paulo SP, Brazil
| | - Massuo J Kato
- Laboratory of Chemistry of Natural Products, Chemistry Institute, Universidade de São Paulo, São Paulo SP, Brazil
| | - Rafael S Oliveira
- Department of Plant Biology, Universidade Estadual de Campinas, Campinas SP, Brazil
| | - Paulo S Oliveira
- Department of Animal Biology, Universidade Estadual de Campinas, Campinas SP, Brazil
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9
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Perkins MJ, Inger R, Bearhop S, Sanders D. Multichannel feeding by spider functional groups is driven by feeding strategies and resource availability. OIKOS 2017. [DOI: 10.1111/oik.04500] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew J. Perkins
- Centre for Ecology and Conservation, School of Biosciences, Univ. of Exeter, Cornwall Campus, Penryn; Cornwall TR10 9EZ UK
- School of Biological Sciences, Univ. of Hong Kong; Hong Kong SAR PR China
| | - Richard Inger
- Environment and Sustainability Inst., Univ. of Exeter, Penryn; Cornwall UK
| | - Stuart Bearhop
- Centre for Ecology and Conservation, School of Biosciences, Univ. of Exeter, Cornwall Campus, Penryn; Cornwall TR10 9EZ UK
| | - Dirk Sanders
- Centre for Ecology and Conservation, School of Biosciences, Univ. of Exeter, Cornwall Campus, Penryn; Cornwall TR10 9EZ UK
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10
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11
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Sitvarin MI, Rypstra AL, Harwood JD. Linking the green and brown worlds through nonconsumptive predator effects. OIKOS 2016. [DOI: 10.1111/oik.03190] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Tiede J, Wemheuer B, Traugott M, Daniel R, Tscharntke T, Ebeling A, Scherber C. Trophic and Non-Trophic Interactions in a Biodiversity Experiment Assessed by Next-Generation Sequencing. PLoS One 2016; 11:e0148781. [PMID: 26859146 PMCID: PMC4747541 DOI: 10.1371/journal.pone.0148781] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Accepted: 01/22/2016] [Indexed: 01/06/2023] Open
Abstract
Plant diversity affects species richness and abundance of taxa at higher trophic levels. However, plant diversity effects on omnivores (feeding on multiple trophic levels) and their trophic and non-trophic interactions are not yet studied because appropriate methods were lacking. A promising approach is the DNA-based analysis of gut contents using next generation sequencing (NGS) technologies. Here, we integrate NGS-based analysis into the framework of a biodiversity experiment where plant taxonomic and functional diversity were manipulated to directly assess environmental interactions involving the omnivorous ground beetle Pterostichus melanarius. Beetle regurgitates were used for NGS-based analysis with universal 18S rDNA primers for eukaryotes. We detected a wide range of taxa with the NGS approach in regurgitates, including organisms representing trophic, phoretic, parasitic, and neutral interactions with P. melanarius. Our findings suggest that the frequency of (i) trophic interactions increased with plant diversity and vegetation cover; (ii) intraguild predation increased with vegetation cover, and (iii) neutral interactions with organisms such as fungi and protists increased with vegetation cover. Experimentally manipulated plant diversity likely affects multitrophic interactions involving omnivorous consumers. Our study therefore shows that trophic and non-trophic interactions can be assessed via NGS to address fundamental questions in biodiversity research.
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Affiliation(s)
- Julia Tiede
- Agroecology, Department of Crop Sciences, Georg-August University Goettingen, Grisebachstr. 6, 37077, Goettingen, Germany
- Institute of Landscape Ecology, University of Muenster, Heisenbergstr. 2, 48149, Muenster, Germany
| | - Bernd Wemheuer
- Institute of Microbiology and Genetics, Department of Genomic and Applied Microbiology, Georg-August University Goettingen, Grisebachstr. 8, 37077, Goettingen, Germany
| | - Michael Traugott
- Mountain Agriculture Research Unit, Institute of Ecology, University of Innsbruck, Technikerstrasse 25, 6020, Innsbruck, Austria
| | - Rolf Daniel
- Institute of Microbiology and Genetics, Department of Genomic and Applied Microbiology, Georg-August University Goettingen, Grisebachstr. 8, 37077, Goettingen, Germany
| | - Teja Tscharntke
- Agroecology, Department of Crop Sciences, Georg-August University Goettingen, Grisebachstr. 6, 37077, Goettingen, Germany
| | - Anne Ebeling
- Institute of Ecology, Friedrich-Schiller-University Jena, Dornburger Str. 159, 07743, Jena, Germany
| | - Christoph Scherber
- Agroecology, Department of Crop Sciences, Georg-August University Goettingen, Grisebachstr. 6, 37077, Goettingen, Germany
- Institute of Landscape Ecology, University of Muenster, Heisenbergstr. 2, 48149, Muenster, Germany
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13
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Grutters BMC, Pollux BJA, Verberk WCEP, Bakker ES. Native and non-native plants provide similar refuge to invertebrate prey, but less than artificial plants. PLoS One 2015; 10:e0124455. [PMID: 25885967 PMCID: PMC4401678 DOI: 10.1371/journal.pone.0124455] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 03/05/2015] [Indexed: 11/19/2022] Open
Abstract
Non-native species introductions are widespread and can affect ecosystem functioning by altering the structure of food webs. Invading plants often modify habitat structure, which may affect the suitability of vegetation as refuge and could thus impact predator-prey dynamics. Yet little is known about how the replacement of native by non-native vegetation affects predator-prey dynamics. We hypothesize that plant refuge provisioning depends on (1) the plant's native status, (2) plant structural complexity and morphology, (3) predator identity, and (4) prey identity, as well as that (5) structurally similar living and artificial plants provide similar refuge. We used aquatic communities as a model system and compared the refuge provided by plants to macroinvertebrates (Daphnia pulex, Gammarus pulex and damselfly larvae) in three short-term laboratory predation experiments. Plant refuge provisioning differed between plant species, but was generally similar for native (Myriophyllum spicatum, Ceratophyllum demersum, Potamogeton perfoliatus) and non-native plants (Vallisneria spiralis, Myriophyllum heterophyllum, Cabomba caroliniana). However, plant refuge provisioning to macroinvertebrate prey depended primarily on predator (mirror carp: Cyprinus carpio carpio and dragonfly larvae: Anax imperator) and prey identity, while the effects of plant structural complexity were only minor. Contrary to living plants, artificial plant analogues did improve prey survival, particularly with increasing structural complexity and shoot density. As such, plant rigidity, which was high for artificial plants and one of the living plant species evaluated in this study (Ceratophyllum demersum), may interact with structural complexity to play a key role in refuge provisioning to specific prey (Gammarus pulex). Our results demonstrate that replacement of native by structurally similar non-native vegetation is unlikely to greatly affect predator-prey dynamics. We propose that modification of predator-prey interactions through plant invasions only occurs when invading plants radically differ in growth form, density and rigidity compared to native plants.
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Affiliation(s)
- Bart M. C. Grutters
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, the Netherlands
| | - Bart J. A. Pollux
- Experimental Zoology Group, Department of Animal Sciences, Wageningen University, Wageningen, the Netherlands
| | - Wilco C. E. P. Verberk
- Department of Animal Ecology and Ecophysiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Nijmegen, the Netherlands
| | - Elisabeth S. Bakker
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, the Netherlands
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14
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Sitvarin MI, Romanchek C, Rypstra AL. Nonconsumptive Predator-Prey Interactions: Sensitivity of the Detritivore Sinella curviseta (Collembola: Entomobryidae) to Cues of Predation Risk From the Spider Pardosa milvina (Araneae: Lycosidae). ENVIRONMENTAL ENTOMOLOGY 2015; 44:349-355. [PMID: 26313189 DOI: 10.1093/ee/nvv011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 01/22/2015] [Indexed: 06/04/2023]
Abstract
Predators can affect prey indirectly when prey respond to cues indicating a risk of predation by altering activity levels. Changes in prey behavior may cascade through the food web to influence ecosystem function. The response of the collembolan Sinella curviseta Brook (Collembola: Entomobryidae) to cues indicating predation risk (necromones and cues from the wolf spider Pardosa milvina (Hentz) (Araneae: Lycosidae)) was tested. Additionally, necromones and predator cues were paired in a conditioning experiment to determine whether the collembolan could form learned associations. Although collembolans did not alter activity levels in response to predator cues, numerous aspects of behavior differed in the presence of necromones. There was no detectable conditioned response to predator cues after pairing with necromones. These results provide insight into how collembolans perceive and respond to predation threats that vary in information content. Previously detected indirect impacts of predator cues on ecosystem function are likely due to changes in prey other than activity level.
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Affiliation(s)
- Michael I Sitvarin
- Department of Entomology, University of Kentucky, S-225 Agricultural Science Center North, Lexington, KY 4054 and Department of Biology, Miami University, 700 E High St., Oxford, OH 45056. Department of Entomology, University of Kentucky, S-225 Agricultural Science Center North, Lexington, KY 40546.
| | - Christian Romanchek
- Department of Entomology, University of Kentucky, S-225 Agricultural Science Center North, Lexington, KY 4054 and Department of Biology, Miami University, 700 E High St., Oxford, OH 45056
| | - Ann L Rypstra
- Department of Biology, Miami University, 1601 University Blvd., Hamilton, OH 45011
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15
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Sitvarin MI, Rypstra AL. Fear of predation alters soil carbon dioxide flux and nitrogen content. Biol Lett 2015; 10:rsbl.2014.0366. [PMID: 24966204 DOI: 10.1098/rsbl.2014.0366] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Predators are known to have both consumptive and non-consumptive effects (NCEs) on their prey that can cascade to affect lower trophic levels. Non-consumptive interactions often drive these effects, though the majority of studies have been conducted in aquatic- or herbivory-based systems. Here, we use a laboratory study to examine how linkages between an above-ground predator and a detritivore influence below-ground properties. We demonstrate that predators can depress soil metabolism (i.e. CO2 flux) and soil nutrient content via both consumptive and non-consumptive interactions with detritivores, and that the strength of isolated NCEs is comparable to changes resulting from predation. Changes in detritivore abundance and activity in response to predators and the fear of predation likely mediate interactions with the soil microbe community. Our results underscore the need to explore these mechanisms at large scales, considering the disproportionate extinction risk faced by predators and the importance of soils in the global carbon cycle.
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Affiliation(s)
| | - Ann L Rypstra
- Department of Biology, Miami University, Hamilton, OH 45011, USA
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16
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Sitvarin MI, Rypstra AL. The importance of intraguild predation in predicting emergent multiple predator effects. Ecology 2014. [DOI: 10.1890/13-2347.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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17
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Zalewski M, Dudek D, Tiunov AV, Godeau JF, Okuzaki Y, Ikeda H, Sienkiewicz P, Ulrich W. High Niche Overlap in the Stable Isotope Space Of Ground Beetles. ANN ZOOL FENN 2014. [DOI: 10.5735/086.051.0302] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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18
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Campos-Herrera R, Ali JG, Diaz BM, Duncan LW. Analyzing spatial patterns linked to the ecology of herbivores and their natural enemies in the soil. FRONTIERS IN PLANT SCIENCE 2013; 4:378. [PMID: 24137165 PMCID: PMC3786222 DOI: 10.3389/fpls.2013.00378] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 09/03/2013] [Indexed: 05/11/2023]
Abstract
Modern agricultural systems can benefit from the application of concepts and models from applied ecology. When understood, multitrophic interactions among plants, pests, diseases and their natural enemies can be exploited to increase crop production and reduce undesirable environmental impacts. Although the understanding of subterranean ecology is rudimentary compared to the perspective aboveground, technologies today vastly reduce traditional obstacles to studying cryptic communities. Here we emphasize advantages to integrating as much as possible the use of these methods in order to leverage the information gained from studying communities of soil organisms. PCR-based approaches to identify and quantify species (real time qPCR and next generation sequencing) greatly expand the ability to investigate food web interactions because there is less need for wide taxonomic expertise within research programs. Improved methods to capture and measure volatiles in the soil atmosphere in situ make it possible to detect and study chemical cues that are critical to communication across trophic levels. The application of SADIE to directly assess rather than infer spatial patterns in belowground agroecosystems has improved the ability to characterize relationships between organisms in space and time. We review selected methodology and use of these tools and describe some of the ways they were integrated to study soil food webs in Florida citrus orchards with the goal of developing new biocontrol approaches.
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Affiliation(s)
- R. Campos-Herrera
- Departamento de Contaminación Ambiental, Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones CientíficasMadrid, Spain
- Entomology and Nematology Department, Citrus Research and Education Center, University of FloridaLake Alfred, FL, USA
| | - J. G. Ali
- Entomology and Nematology Department, Citrus Research and Education Center, University of FloridaLake Alfred, FL, USA
- Department of Ecology and Evolutionary Biology, Cornell UniversityIthaca, NY, USA
| | - B. M. Diaz
- Departamento de Protección Vegetal, Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones CientíficasMadrid, Spain
| | - L. W. Duncan
- Entomology and Nematology Department, Citrus Research and Education Center, University of FloridaLake Alfred, FL, USA
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19
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Plant production and alternate prey channels impact the abundance of top predators. Oecologia 2013; 173:331-41. [PMID: 23604861 DOI: 10.1007/s00442-013-2618-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 02/05/2013] [Indexed: 10/26/2022]
Abstract
While numerous studies have examined the effects of increased primary production on higher trophic levels, most studies have focused primarily on the grazing food web and have not considered the importance of alternate prey channels. This has happened despite the fact that fertilization not only increases grazing herbivore abundance, but other types of consumers such as detritivores that serve as alternate prey for generalist predators. Alternate prey channels can sustain generalist predators at times when prey abundance in the grazing food web is low, thus increasing predator densities and the potential for trophic cascades. Using arthropod data from a fertilization experiment, we constructed a hierarchical Bayesian model to examine the direct and indirect effects of plant production and alternate prey channels on predators in a salt marsh. We found that increased plant production positively affected the density of top predators via effects on lower trophic level herbivores and mesopredators. Additionally, while the abundance of algivores and detritivores positively affected mesopredators and top predators, respectively, the effects of alternate prey were relatively weak. Because previous studies in the same system have found that mesopredators and top predators rely on alternate prey such as algivores and detritivores, future studies should examine whether fertilization shifts patterns of prey use by predators from alternate channels to the grazing channel. Finally, the hierarchical Bayesian model used in this study provided a useful method for exploring trophic relationships in the salt marsh food web, especially where causal relationships among trophic groups were unknown.
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Murphy SM, Wimp GM, Lewis D, Denno RF. Nutrient presses and pulses differentially impact plants, herbivores, detritivores and their natural enemies. PLoS One 2012; 7:e43929. [PMID: 22952814 PMCID: PMC3429447 DOI: 10.1371/journal.pone.0043929] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 07/27/2012] [Indexed: 11/18/2022] Open
Abstract
Anthropogenic nutrient inputs into native ecosystems cause fluctuations in resources that normally limit plant growth, which has important consequences for associated food webs. Such inputs from agricultural and urban habitats into nearby natural systems are increasing globally and can be highly variable, spanning the range from sporadic to continuous. Despite the global increase in anthropogenically-derived nutrient inputs into native ecosystems, the consequences of variation in subsidy duration on native plants and their associated food webs are poorly known. Specifically, while some studies have examined the effects of nutrient subsidies on native ecosystems for a single year (a nutrient pulse), repeated introductions of nutrients across multiple years (a nutrient press) better reflect the persistent nature of anthropogenic nutrient enrichment. We therefore contrasted the effects of a one-year nutrient pulse with a four-year nutrient press on arthropod consumers in two salt marshes. Salt marshes represent an ideal system to address the differential impacts of nutrient pulses and presses on ecosystem and community dynamics because human development and other anthropogenic activities lead to recurrent introductions of nutrients into these natural systems. We found that plant biomass and %N as well as arthropod density fell after the nutrient pulse ended but remained elevated throughout the nutrient press. Notably, higher trophic levels responded more strongly than lower trophic levels to fertilization, and the predator/prey ratio increased each year of the nutrient press, demonstrating that food web responses to anthropogenic nutrient enrichment can take years to fully manifest themselves. Vegetation at the two marshes also exhibited an apparent tradeoff between increasing %N and biomass in response to fertilization. Our research emphasizes the need for long-term, spatially diverse studies of nutrient enrichment in order to understand how variation in the duration of anthropogenic nutrient subsidies affects native ecosystems.
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Affiliation(s)
- Shannon M Murphy
- Department of Biological Sciences, University of Denver, Denver, Colorado, United States of America.
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