1
|
Lemmen KD, Pennekamp F. Food web context modifies predator foraging and weakens trophic interaction strength. Ecol Lett 2024; 27:e14475. [PMID: 39060898 DOI: 10.1111/ele.14475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 06/21/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024]
Abstract
Trophic interaction modifications (TIM) are widespread in natural systems and occur when a third species indirectly alters the strength of a trophic interaction. Past studies have focused on documenting the existence and magnitude of TIMs; however, the underlying processes and long-term consequences remain elusive. To address this gap, we experimentally quantified the density-dependent effect of a third species on a predator's functional response. We conducted short-term experiments with ciliate communities composed of a predator, prey and non-consumable 'modifier' species. In both communities, increasing modifier density weakened the trophic interaction strength, due to a negative effect on the predator's space clearance rate. Simulated long-term dynamics indicate quantitative differences between models that account for TIMs or include only pairwise interactions. Our study demonstrates that TIMs are important to understand and predict community dynamics and highlights the need to move beyond focal species pairs to understand the consequences of species interactions in communities.
Collapse
Affiliation(s)
- Kimberley D Lemmen
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Frank Pennekamp
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| |
Collapse
|
2
|
Reese TC, Blakeslee AMH, Crane LC, Fletcher LS, Repetto MF, Smith N, Stancil C, Tepolt CK, Toscano BJ, Griffen BD. Shift from income breeding to capital breeding with latitude in the invasive Asian shore crab Hemigrapsus sanguineus. Sci Rep 2024; 14:6654. [PMID: 38509340 PMCID: PMC10954667 DOI: 10.1038/s41598-024-57434-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 03/18/2024] [Indexed: 03/22/2024] Open
Abstract
Organisms vary in the timing of energy acquisition and use for reproduction. Thus, breeding strategies exist on a continuum, from capital breeding to income breeding. Capital breeders acquire and store energy for breeding before the start of the reproductive season, while income breeders finance reproduction using energy acquired during the reproductive season. Latitude and its associated environmental drivers are expected to heavily influence breeding strategy, potentially leading to latitudinal variation in breeding strategies within a single species. We examined the breeding strategy of the Asian shore crab Hemigrapsus sanguineus at five sites spanning nearly 10° of latitude across its invaded United States range. We hypothesized that the primary breeding strategy of this species would shift from income breeding to capital breeding as latitude increases. We found that though this species' breeding strategy is dominated by capital breeding throughout much of the range, income breeding increases in importance at lower latitudes. This latitudinal pattern is likely heavily influenced by the duration of the foraging and breeding seasons, which also vary with latitude. We also found that reproductive characteristics at the northern and southern edges of the invaded range were consistent with continued range expansion. We suggest that the reproductive flexibility of the Asian shore crab is a key facilitator of its continued invasion success. Our results highlight the influence of latitude on the breeding strategy of a species and emphasize the need for further research regarding the ecological importance and implications of flexibility in breeding strategies within species.
Collapse
Affiliation(s)
- Tanner C Reese
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA
| | | | - Laura C Crane
- Wells National Estuarine Research Reserve, Wells, ME, 04090, USA
| | - Laura S Fletcher
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA
| | - Michele F Repetto
- Department of Biology, Temple University, Philadelphia, PA, 19122, USA
| | - Nanette Smith
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA
| | - Carter Stancil
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA
| | - Carolyn K Tepolt
- Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | | | - Blaine D Griffen
- Department of Biology, Brigham Young University, Provo, UT, 84602, USA.
| |
Collapse
|
3
|
Kulessa AK, Balzani P, Soto I, Toutain M, Haubrock PJ, Kouba A. Assessing the potential phytosanitary threat of the house cricket Acheta domesticus. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 917:170376. [PMID: 38281629 DOI: 10.1016/j.scitotenv.2024.170376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/20/2024] [Accepted: 01/21/2024] [Indexed: 01/30/2024]
Abstract
Phytosanitary threats can pose substantial risks to global agriculture and ecological systems, affecting biodiversity, human well-being, and food security. Meanwhile, global warming is projected to exacerbate these threats in the future. One in Europe already widely distributed potential phytosanitary threat that may benefit from global warming is the house cricket Acheta domesticus. This study explored the potential of A. domesticus as a relevant non-native phytosanitary threat under changing climatic conditions by conducting a series of functional response experiments across a temperature gradient (20, 25, and 30 °C). Acheta domesticus exhibited comparable patterns of seed consumption and functional responses. Seed type (millet seeds, wheat grains) and temperature increase influenced the damage inflicted on seeds, with softer and smaller seeds being more susceptible to damage, further amplified by warmer temperatures. The study's outcomes underline the phytosanitary threat that A. domesticus may pose. Considering the species' established presence and adaptable nature in urban environments exacerbates the potential for A. domesticus to transition to rural and agricultural areas. Its increasing production as a food item, paired with the here-identified potential to damage seeds, emphasizes the need for proactive and science-based strategies to address emerging phytosanitary threats driven by non-native species under changing climatic conditions. As global temperatures continue to rise, the assessment and management of potential pest species like A. domesticus will be crucial for safeguarding agriculture productivity and ecological balance.
Collapse
Affiliation(s)
- Anna K Kulessa
- Ruhr University Bochum, Faculty of Biology and Biotechnology, 44801 Bochum, Germany; University of Duisburg-Essen, Faculty of Biology, 45141 Essen, Germany; Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in České Budějovice, 389 25 Vodňany, Czech Republic.
| | - Paride Balzani
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in České Budějovice, 389 25 Vodňany, Czech Republic
| | - Ismael Soto
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in České Budějovice, 389 25 Vodňany, Czech Republic
| | - Mathieu Toutain
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in České Budějovice, 389 25 Vodňany, Czech Republic; Université de Rennes, CNRS, ECOBIO [(Ecosystèmes, biodiversité, évolution)], 35000 Rennes, France
| | - Phillip J Haubrock
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in České Budějovice, 389 25 Vodňany, Czech Republic; Department of River Ecology and Conservation, Senckenberg Research Institute and Natural History Museum Frankfurt, 63571 Gelnhausen, Germany; CAMB, Center for Applied Mathematics and Bioinformatics, Gulf University for Science and Technology, Hallawy 32093, Kuwait
| | - Antonín Kouba
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in České Budějovice, 389 25 Vodňany, Czech Republic
| |
Collapse
|
4
|
Ward CA, Tunney TD, McCann KS. Managing aquatic habitat structure for resilient trophic interactions. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2023; 33:e2814. [PMID: 36708058 DOI: 10.1002/eap.2814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 08/25/2022] [Accepted: 12/08/2022] [Indexed: 06/18/2023]
Abstract
Structural habitat (the three-dimensional arrangement of physical matter, abiotic and biotic, at a location) is a foundational element for the resilience and maintenance of biodiversity, yet anthropogenic development is driving the global simplification of aquatic environments. Resource managers regularly seek to conserve aquatic food webs by increasing structural habitat complexity with expected benefits to fisheries; however, the global effectiveness of such actions is unclear. Our synthesis and theoretical analyses found that the response of a consumer-resource interaction (predatory sportfish and forage fish prey) to the addition of prey refuge habitat differed among systems with low and high rates of biomass transfer from resource to consumer (i.e., biomass potential); stabilization was not the rule. Greater prey refuge habitat availability tended to stabilize systems characterized by high biomass potential while simultaneously increasing consumer densities. In contrast, increasing prey refuge habitat availability in systems characterized by low biomass potential tended to mute energy transfer and moved consumer densities toward local extinction. Importantly, biomass potential and prey refuge can have antagonistic effects on stability and relative consumer densities, and it is therefore important to consider the local conditions of a system when using habitat manipulation as a management measure. Further development of our context-dependent perspective to whole food webs, and across different environments, may help to guide structural habitat management to better restore and protect aquatic ecosystems.
Collapse
Affiliation(s)
- Charlotte A Ward
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Tyler D Tunney
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
- Fisheries and Oceans Canada, Gulf Region, Freshwater Habitat Section, Centre for Effectiveness Science, Moncton, New Brunswick, Canada
| | - Kevin S McCann
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| |
Collapse
|
5
|
Kalinkat G, Rall BC, Uiterwaal SF, Uszko W. Empirical evidence of type III functional responses and why it remains rare. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1033818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023] Open
Abstract
More than 70 years after its introduction, the framework of resource density-dependent consumption rates, also known as predator-prey functional responses, remains a core concept in population and food web ecology. Initially, three types of responses were defined: linear (type I), hyperbolic (type II), and sigmoid (type III). Due to its potential to stabilize consumer-resource population dynamics, the sigmoid type III functional response immediately became a “holy grail” in population ecology. However, experimentally proving that type III functional responses exist, whether in controlled laboratory systems or in nature, was challenging. While theoretical and practical advances make identifying type III responses easier today, decades of research have brought only a limited number of studies that provide empirical evidence for type III response curves. Here, we review this evidence from laboratory- and field-based studies published during the last two decades. We found 107 studies that reported type III responses, but these studies ranged across various taxa, interaction types, and ecosystems. To put these studies into context, we also discuss the various biological mechanisms that may lead to the emergence of type III responses. We summarize how three different and mutually independent intricacies bedevil the empirical documentation of type III responses: (1) challenges in statistical modeling of functional responses, (2) inadequate resource density ranges and spacing, and (3) biologically meaningful and realistic design of experimental arenas. Finally, we provide guidelines on how the field should move forward based on these considerations.
Collapse
|
6
|
Coughlan NE, Dickey JWE, Dick JTA, Médoc V, McCard M, Lacroix G, Fiorini S, Millot A, Cuthbert RN. When worlds collide: Invader-driven benthic habitat complexity alters predatory impacts of invasive and native predatory fishes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156876. [PMID: 35760170 DOI: 10.1016/j.scitotenv.2022.156876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 05/27/2022] [Accepted: 06/18/2022] [Indexed: 06/15/2023]
Abstract
Interactions between multiple invasive alien species (IAS) might increase their ecological impacts, yet relatively few studies have attempted to quantify the effects of facilitative interactions on the success and impact of aquatic IAS. Further, the effect of abiotic factors, such as habitat structure, have lacked consideration in ecological impact prediction for many high-profile IAS, with most data acquired through simplified assessments that do not account for real environmental complexities. In the present study, we assessed a potential facilitative interaction between a predatory invasive fish, the Ponto-Caspian round goby (Neogobius melanostomus), and an invasive bivalve, the Asian clam (Corbicula fluminea). We compared N. melanostomus functional responses (feeding-rates under different prey densities) to a co-occurring endangered European native analogue fish, the bullhead (Cottus gobio), in the presence of increased levels of habitat complexity driven by the accumulation of dead C. fluminea biomass that persists within the environment (i.e. 0, 10, 20 empty bivalve shells). Habitat complexity significantly influenced predation, with consumption in the absence of shells being greater than where 10 or 20 shells were present. However, at the highest shell density, invasive N. melanostomus maximum feeding-rates and functional response ratios were substantially higher than those of native C. gobio. Further, the Relative Impact Potential metric, by combining per capita effects and population abundances, indicated that higher shell densities exacerbate the relative impact of the invader. It therefore appears that N. melanostomus can better tolerate higher IAS shell abundances when foraging at high prey densities, suggesting the occurrence of an important facilitative interaction. Our data are thus fully congruent with field data that link establishment success of N. melanostomus with the presence of C. fluminea. Overall, we show that invader-driven benthic habitat complexity can alter the feeding-rates and thus impacts of predatory fishes, and highlight the importance of inclusion of abiotic factors in impact prediction assessments for IAS.
Collapse
Affiliation(s)
- Neil E Coughlan
- School of Biological, Earth & Environmental Sciences, University College Cork, Distillery Fields, North Mall, Cork, Ireland; Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL, UK.
| | - James W E Dickey
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL, UK; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), 12587 Berlin, Germany; Freie Universität Berlin, Institute of Biology, Königin-Luise-Str. 1-3, 14195 Berlin, Germany; GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, 24105 Kiel, Germany
| | - Jaimie T A Dick
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL, UK
| | - Vincent Médoc
- Equipe Neuro Ethologie Sensorielle, ENES/Neuro-PSI CNRS UMR 9197, Université de Lyon/Saint-Etienne, Saint-Etienne, France
| | - Monica McCard
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL, UK
| | - Gérard Lacroix
- iEES-Paris, Institut d'Ecologie et des Sciences de l'Environnement de Paris, UMR 7618 (CNRS, INRAE, IRD, Sorbonne Université, UPEC, Université de Paris), CC237 Paris, France; Ecole Normale Supérieure, PSL Research University, CNRS, Centre de Recherche en Écologie Expérimentale et Prédictive (CEREEP-Ecotron Ile-De-France), UAR 3194 Saint-Pierre-lès-Nemours, France
| | - Sarah Fiorini
- Ecole Normale Supérieure, PSL Research University, CNRS, Centre de Recherche en Écologie Expérimentale et Prédictive (CEREEP-Ecotron Ile-De-France), UAR 3194 Saint-Pierre-lès-Nemours, France
| | - Alexis Millot
- Ecole Normale Supérieure, PSL Research University, CNRS, Centre de Recherche en Écologie Expérimentale et Prédictive (CEREEP-Ecotron Ile-De-France), UAR 3194 Saint-Pierre-lès-Nemours, France
| | - Ross N Cuthbert
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, Northern Ireland BT9 5DL, UK
| |
Collapse
|
7
|
Predicting ecological impacts of the invasive brush-clawed shore crab under environmental change. Sci Rep 2022; 12:9988. [PMID: 35705603 PMCID: PMC9200808 DOI: 10.1038/s41598-022-14008-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 05/31/2022] [Indexed: 11/17/2022] Open
Abstract
Globally, the number of invasive non-indigenous species is continually rising, representing a major driver of biodiversity declines and a growing socio-economic burden. Hemigrapsus takanoi, the Japanese brush-clawed shore crab, is a highly successful invader in European seas. However, the ecological consequences of this invasion have remained unexamined under environmental changes—such as climatic warming and desalination, which are projected in the Baltic Sea—impeding impact prediction and management. Recently, the comparative functional response (resource use across resource densities) has been pioneered as a reliable approach to quantify and predict the ecological impacts of invasive non-indigenous species under environmental contexts. This study investigated the functional response of H. takanoi factorially between different crab sexes and under environmental conditions predicted for the Baltic Sea in the contexts of climate warming (16 and 22 °C) and desalination (15 and 10), towards blue mussel Mytilus edulis prey provided at different densities. Hemigrapsus takanoi displayed a potentially population-destabilising Type II functional response (i.e. inversely-density dependent) towards mussel prey under all environmental conditions, characterised by high feeding rates at low prey densities that could extirpate prey populations—notwithstanding high in-field abundances of M. edulis. Males exhibited higher feeding rates than females under all environmental conditions. Higher temperatures reduced the feeding rate of male H. takanoi, but did not affect the feeding rate of females. Salinity did not have a clear effect on feeding rates for either sex. These results provide insights into interactions between biological invasions and climate change, with future warming potentially lessening the impacts of this rapidly spreading marine invader, depending on the underlying population demographics and abundances.
Collapse
|
8
|
Effects of substrate and elevated temperature on the growth and feeding efficiency of an invasive cyprinid fish, Tench (Tinca tinca). Biol Invasions 2022. [DOI: 10.1007/s10530-022-02778-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
9
|
Functional Responses and Additive Multiple Predator Effects of Two Common Wetland Fish. WATER 2022. [DOI: 10.3390/w14050699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Understanding trophic interactions is essential for the prediction and measurement of structure and function in aquatic environments. Communities in these ecosystems may be shaped by variables such as predator diversity, prey density and emergent multiple predator effects (MPEs), which are likely to influence trophic dynamics. In this study, we examined the effect of key predatory fish in floodplain wetlands, namely Oreochromis mossambicus and Enteromius paludinosus, towards Chironomidae prey, using a comparative functional response (FR) approach. We used single predator species as well as intra- and interspecific paired species to contrast FRs under multiple predator scenarios. Attack rate and handling time estimates from single predator FRs were used to predict multiple predators’ feeding rates, which were compared to observe multiple predators’ feeding rates to quantify potential MPEs. From single fish trials, each species displayed a significant Type II FR, characterized by high feeding rates at low prey densities. Oreochromis mossambicus had a steeper (initial slope, i.e., higher attack rate) and higher (asymptote of curve, i.e., shorter handling time and higher maximum feeding rate) FR, whereas E. paludinosus exhibited lower-magnitude FRs (i.e., lower attack rate, longer handling time and lower feeding rate). In multiple predator scenarios, feeding rates were well-predicted by those of single predators, both in conspecific and interspecific pairs, and thus we did not find evidence for antagonistic or synergistic MPEs. Predator–prey interactions in wetland systems can have significant consequences on the structure and dynamics of ecological communities. In turn, this could have destabilizing effects on resources in tropical wetlands. These results, although experimental, help us understand how trophic interaction among conspecific or interspecific fish species in Austral tropical wetlands might influence their aquatic prey species. This will help us to understand food web dynamics better.
Collapse
|
10
|
Cuthbert RN, Briski E. Temperature, not salinity, drives impact of an emerging invasive species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 780:146640. [PMID: 33774308 DOI: 10.1016/j.scitotenv.2021.146640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
Biological invasions are a growing ecological and socioeconomic problem worldwide. While robust predictions of impactful future invaders are urgently needed, understandings of invader impacts have been challenged by context-dependencies. In aquatic systems in particular, future climate change could alter the impacts of invasive non-native species. Widespread warming coupled with sea freshening may exacerbate ecological impacts of invaders in marine environments, compromising ecosystem structure, function and stability. We examined how multiple abiotic changes affect the potential ecological impact of an emerging invasive non-native species from the Ponto-Caspian region - a notorious origin hotspot for invaders, characterised by high salinity and temperature variation. Using a comparative functional response (feeding rates across prey densities) approach, the potential ecological impacts of the gammarid Pontogammarus maeoticus towards native chironomid prey were examined across a range of current and future temperature (18, 22 °C) and salinity (14, 10, 6, 2 ppt) regimes in a factorial design. Feeding rates of P. maeoticus on prey significantly increased with temperature (by 60%), but were not significantly affected by salinity regime. Gammarids displayed significant Type II functional responses, with attack rates not significantly affected by warming across all salinities. Handling times were, however, shortened by warming, and thus maximum feeding rates significantly increased, irrespective of salinity regime. Functional responses were significantly different following warming at high prey densities under all salinities, except under the ambient 10 ppt. Euryhalinity of invasive non-native species from the Ponto-Caspian region thus could allow sustained ecological impacts across a range of salinity regimes. These results corroborate high invasion success and field impacts of Ponto-Caspian gammarids in brackish through to freshwater ecosystems. Climate warming will likely worsen the potential ecological impact of P. maeoticus. With invasions growing worldwide, quantifications of how combined elements of climate change will alter the impacts of emerging invasive non-native species are needed.
Collapse
Affiliation(s)
- Ross N Cuthbert
- GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, Kiel, Germany.
| | | |
Collapse
|
11
|
Functional Response and Predation Rate of Dicyphus cerastii Wagner (Hemiptera: Miridae). INSECTS 2021; 12:insects12060530. [PMID: 34200391 PMCID: PMC8229145 DOI: 10.3390/insects12060530] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 11/30/2022]
Abstract
Simple Summary Biological control (BC) is an effective way to regulate pest populations in horticultural crops, allowing the decrease of pesticide usage. On tomato, predatory insects like plant bugs or mirids provide BC services against several insect pests. Native predators are adapted to local conditions of climate and ecology and therefore may be well suited to provide BC services. Dicyphus cerastii is a predatory mirid that is present in the Mediterranean region and occurs in tomato greenhouses in Portugal. However, little is known about its contribution to BC in this crop. In this study, we evaluated how prey consumption is affected by increasing prey abundance on four different prey, in laboratory conditions. We found that the predator can increase its predation rate until a maximum is reached and that prey characteristics like size and mobility can affect predation. Dicyphus cerastii showed high predation rates for all prey species tested, allowing us to conclude that this species is an interesting predator for BC in tomato crops. Abstract Dicyphine mirids are important biological control agents (BCAs) in horticultural crops. Dicyphus cerastii Wagner can be found in protected tomato crops in Portugal, and has been observed feeding on several tomato pests. However, the predation capacity of this species is poorly studied. In order to investigate the predation capacity of D. cerastii, and how it is affected by prey size and mobility, we evaluated the functional response (FR) and predation rate of female predators on different densities of four prey species: Myzus persicae 1st instar nymphs (large mobile prey), Bemisia tabaci 4th instar nymphs, Ephestia kuehniella eggs (large immobile prey) and Tuta absoluta eggs (small immobile prey). Experiments were performed on tomato leaflets in Petri dish arenas for 24 h. Dicyphus cerastii exhibited type II FR for all prey tested. The predator effectively preyed upon all prey, consuming an average of 88.8 B. tabaci nymphs, 134.4 E. kuehniella eggs, 37.3 M. persicae nymphs and 172.3 T. absoluta eggs. Differences in the FR parameters, attack rate and handling time, suggested that prey size and mobility affected predation capacity. Considering the very high predation rates found for all prey species, D. cerastii proved to be an interesting candidate BCA for tomato crops.
Collapse
|
12
|
Anthropogenic water conditions amplify predatory impact of the non-native Oriental river prawn Macrobrachium nipponense. Biol Invasions 2021. [DOI: 10.1007/s10530-021-02466-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
13
|
Mocq J, Soukup PR, Näslund J, Boukal DS. Disentangling the nonlinear effects of habitat complexity on functional responses. J Anim Ecol 2021; 90:1525-1537. [PMID: 33713437 DOI: 10.1111/1365-2656.13473] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 02/17/2021] [Indexed: 11/28/2022]
Abstract
Structural complexity of habitats modifies trophic interactions by providing refuges and altering predator and prey behaviour. Nonlinear effects on trophic interaction strengths driven by these mechanisms may alter food web dynamics and community structure in response to habitat modifications. However, changes in functional response, the relationship between prey density and feeding rate, along habitat complexity (HC) gradients are little understood. We quantified functional responses along a HC gradient from an entirely unstructured to highly structured habitat in a freshwater system, using dragonfly larvae (Aeshna cyanea) preying on Chaoborus obscuripes larvae. To disentangle mechanisms by which changes in HC affect functional responses, we used two different approaches-a population-level and a behavioural experiment-applied an information theoretic approach to identify plausible links between HC and functional response parameters, and compared our results to previous studies. Functional response shape did not change, but we found strong evidence for nonlinear dependence of attack rate and handling time on HC in our study. Combined results from both experiments imply that attack rate increased stepwise between the unstructured and structured habitats in line with the threshold hypothesis, because the predators gained better access to the prey. Handling time was lowest at an intermediate HC level in the population-level experiment while the direct estimate of handling time did not vary with HC in the behavioural experiment. These differences point towards HC-driven changes in foraging activity and other predator and prey behaviour. Most previous studies reported stepwise decrease in attack rate in line with the threshold hypothesis or no change with increasing HC. Moreover, changes in the handling time parameter with HC appear to be relatively common but not conforming to the threshold hypothesis. Overall, increased HC appears to, respectively, weaken and strengthen trophic links in 2D and 3D predator-prey interactions. We conclude that detailed understanding of HC effects on food webs requires complementary experimental approaches across HC gradients that consider predator foraging strategies and predator and prey behaviour. Such studies can also help guide conservation efforts as addition of structural elements is frequently used for restoration of degraded aquatic habitats.
Collapse
Affiliation(s)
- Julien Mocq
- Faculty of Science, Department of Ecosystem Biology & Soil and Water Research Infrastructure, University of South Bohemia, České Budějovice, Czech Republic.,Biology Centre, Institute of Entomology, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Pavel R Soukup
- Faculty of Science, Department of Ecosystem Biology & Soil and Water Research Infrastructure, University of South Bohemia, České Budějovice, Czech Republic.,Biology Centre, Institute of Entomology, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Joacim Näslund
- Faculty of Science, Department of Ecosystem Biology & Soil and Water Research Infrastructure, University of South Bohemia, České Budějovice, Czech Republic.,Department of Aquatic Resources, Institute of Freshwater Research, Swedish University of Agricultural Sciences, Drottningholm, Sweden
| | - David S Boukal
- Faculty of Science, Department of Ecosystem Biology & Soil and Water Research Infrastructure, University of South Bohemia, České Budějovice, Czech Republic.,Biology Centre, Institute of Entomology, Czech Academy of Sciences, České Budějovice, Czech Republic
| |
Collapse
|
14
|
Beardsell A, Gravel D, Berteaux D, Gauthier G, Clermont J, Careau V, Lecomte N, Juhasz CC, Royer-Boutin P, Bêty J. Derivation of Predator Functional Responses Using a Mechanistic Approach in a Natural System. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.630944] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The functional response is at the core of any predator-prey interactions as it establishes the link between trophic levels. The use of inaccurate functional response can profoundly affect the outcomes of population and community models. Yet most functional responses are evaluated using phenomenological models which often fail to discriminate among functional response shapes and cannot identify the proximate mechanisms regulating predator acquisition rates. Using a combination of behavioral, demographic, and experimental data collected over 20 years, we develop a mechanistic model based on species traits and behavior to assess the functional response of a generalist mammalian predator, the arctic fox (Vulpes lagopus), to various tundra prey species (lemmings and the nests of geese, passerines, and sandpipers). Predator acquisition rates derived from the mechanistic model were consistent with field observations. Although acquisition rates slightly decrease at high goose nest and lemming densities, none of our simulations resulted in a saturating response in all prey species. Our results highlight the importance of predator searching components in predator-prey interactions, especially predator speed, while predator acquisition rates were not limited by handling processes. By combining theory with field observations, our study provides support that the predator acquisition rate is not systematically limited at the highest prey densities observed in a natural system. Our study also illustrates how mechanistic models based on empirical estimates of the main components of predation can generate functional response shapes specific to the range of prey densities observed in the wild. Such models are needed to fully untangle proximate drivers of predator-prey population dynamics and to improve our understanding of predator-mediated interactions in natural communities.
Collapse
|
15
|
Born-Torrijos A, Paterson RA, van Beest GS, Vyhlídalová T, Henriksen EH, Knudsen R, Kristoffersen R, Amundsen PA, Soldánová M. Cercarial behaviour alters the consumer functional response of three-spined sticklebacks. J Anim Ecol 2021; 90:978-988. [PMID: 33481253 DOI: 10.1111/1365-2656.13427] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 01/04/2021] [Indexed: 01/16/2023]
Abstract
Free-living parasite life stages may contribute substantially to ecosystem biomass and thus represent a significant source of energy flow when consumed by non-host organisms. However, ambient temperature and the predator's own infection status may modulate consumption rates towards parasite prey. We investigated the combined effects of temperature and predator infection status on the consumer functional response of three-spined sticklebacks towards the free-living cercariae stages of two common freshwater trematode parasites (Plagiorchis spp., Trichobilharzia franki). Our results revealed genera-specific functional responses and consumption rates towards each parasite prey: Type II for Plagiorchis spp. and Type III for T. franki, with an overall higher consumption rate on T. franki. Elevated temperature (13°C) increased the consumption rate on Plagiorchis spp. prey for sticklebacks with mild cestode infections (<5% fish body weight) only. High consumption of cercarial prey by sticklebacks may impact parasite population dynamics by severely reducing or even functionally eliminating free-living parasite life stages from the environment. This supports the potential role of fish as biocontrol agents for cercariae with similar dispersion strategies, in instances where functional response relationships have been established. Our study demonstrates how parasite consumption by non-host organisms may be shaped by traits inherent to parasite transmission and dispersal, and emphasises the need to consider free-living parasite life stages as integral energy resources in aquatic food webs.
Collapse
Affiliation(s)
- Ana Born-Torrijos
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Rachel A Paterson
- School of Biosciences, Cardiff University, Cardiff, UK.,The Norwegian Institute for Nature Research, Trondheim, Norway
| | - Gabrielle S van Beest
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.,Cavanilles Institute for Biodiversity and Evolutionary Biology, Science Park, University of Valencia, Valencia, Spain
| | - Tereza Vyhlídalová
- Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Eirik H Henriksen
- Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Rune Knudsen
- Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Roar Kristoffersen
- Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Per-Arne Amundsen
- Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Miroslava Soldánová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| |
Collapse
|
16
|
Boulding E, Behrens Yamada S, Schooler S, Shanks A. Periodic invasions during El Niño events by the predatory lined shore crab (Pachygrapsus crassipes): forecasted effects of its establishment on direct-developing indigenous prey species (Littorinaspp.). CAN J ZOOL 2020. [DOI: 10.1139/cjz-2019-0250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Coevolutionary arms races between shelled gastropods and their predators are more escalated near the equator. Therefore, temperate gastropods are predicted to be maladapted to highly specialized tropical shell-crushing crabs. The northern geographical limit of the lined shore crab (Pachygrapsus crassipes J.W. Randall, 1840) does not usually overlap with the southern limit of the Sitka periwinkle (Littorina sitkana Philippi, 1846), which lacks a pelagic larval stage. Large El Niño events increased the winter abundance and poleward transport of P. crassipes larvae from California (USA) in the Davidson Current. Temporary intertidal crab populations that included females with eggs were observed 1–4 years later, >1000 km north of its usual geographical range. Laboratory experiments showed that L. sitkana did not have a size refuge from adult P. crassipes. Moreover, consumption rates of adult L. sitkana by P. crassipes were 10-fold higher than those published for indigenous purple shore crabs (Hemigrapsus nudus (Dana, 1851)) with similar claw sizes. Additionally, the upper intertidal limit of invading P. crassipes was higher than that of H. nudus. Consequently, the invasion of P. crassipes reduced the width of L. sitkana‘s spatial refuge from predation. The permanent presence of this subtropical predator could reduce the intertidal distribution of this temperate gastropod, thereby causing contraction of its southern range limit.
Collapse
Affiliation(s)
- E.G. Boulding
- Department of Integrative Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - S. Behrens Yamada
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331, USA
| | - S.S. Schooler
- South Slough National Estuarine Research Reserve, P.O. Box 5417, Charleston, OR 97420, USA
| | - A.L. Shanks
- Oregon Institute of Marine Biology, P.O. Box 5389, Charleston, OR 97420, USA
| |
Collapse
|
17
|
Mathers KL, White JC, Guareschi S, Hill MJ, Heino J, Chadd R. Invasive crayfish alter the long‐term functional biodiversity of lotic macroinvertebrate communities. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13644] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kate L. Mathers
- Geography and Environment Loughborough University Loughborough UK
- Eawag: Swiss Federal Institute of Aquatic Science and TechnologyDepartment of Surface Waters Research and Management Kastanienbaum Switzerland
| | - James C. White
- River Restoration Centre Cranfield University Cranfield UK
| | - Simone Guareschi
- Geography and Environment Loughborough University Loughborough UK
| | - Matthew J. Hill
- School of Applied Sciences University of Huddersfield Huddersfield UK
| | - Jani Heino
- Finnish Environment InstituteFreshwater Centre Oulu Finland
| | | |
Collapse
|
18
|
Lumpkin WP, Stirek KR, Dyer LA. Macrophyte Diversity and Complexity Reduce Larval Mosquito Abundance. JOURNAL OF MEDICAL ENTOMOLOGY 2020; 57:1041-1048. [PMID: 32006421 DOI: 10.1093/jme/tjaa012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Indexed: 06/10/2023]
Abstract
The role of aquatic arthropod diversity and community interactions of larval mosquitoes are important for understanding mosquito population dynamics. We tested the effects of aquatic macrophyte diversity and habitat structural complexity in shaping the predator and competitor invertebrate communities associated with mosquito larvae. Experimental mesocosms were planted with live aquatic macrophytes and allowed to be naturally colonized by local invertebrates. Results indicated a positive effect of macrophyte diversity on competitor diversity and a negative effect on predator diversity. In turn, predator diversity negatively impacted mosquito abundance through a direct effect, while competitor diversity showed an indirect negative effect on mosquito larval abundance through its positive effect on predator diversity. The enhancement of aquatic macrophyte diversity and structural complexity has practical applications for the reduction of mosquito populations in managed systems where complete source elimination is not possible.
Collapse
Affiliation(s)
- Will P Lumpkin
- Department of Biology, University of Nevada Reno, Reno, NV
| | - Kincade R Stirek
- Department of Biological Sciences, Towson University, Towson, MD
| | - Lee A Dyer
- Department of Biology, University of Nevada Reno, Reno, NV
| |
Collapse
|
19
|
Haubrock PJ, Cuthbert RN, Veselý L, Balzani P, Baker NJ, Dick JTA, Kouba A. Predatory functional responses under increasing temperatures of two life stages of an invasive gecko. Sci Rep 2020; 10:10119. [PMID: 32572111 PMCID: PMC7308338 DOI: 10.1038/s41598-020-67194-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 06/01/2020] [Indexed: 11/09/2022] Open
Abstract
The direct effects of temperature increases and differences among life-history might affect the impacts of native and invasive predators on recipient communities. Comparisons of functional responses can improve our understanding of underlying processes involved in altering species interaction strengths and may predict the effect of species invading new communities. Therefore, we investigated the functional responses of the mourning gecko Lepidodactylus lugubris (Duméril & Bibron, 1836) to explore how temperature, body-size and prey density alter gecko predatory impacts in ecosystems. We quantified the functional responses of juvenile and adult geckos in single-predator experiments at 20, 23 and 26 °C. Both displayed saturating Type-II functional responses, but juvenile functional responses and the novel Functional Response Ratio were positively affected by temperature as juvenile attack rates (a) increased as a function of increased temperature. Handling times (h) tended to shorten at higher temperature for both predator stages. We demonstrate that the effects of temperature on functional responses of geckos differ across ontogeny, perhaps reflecting life-history stages prioritising growth and maturation or body maintenance. This indicates that temperature-dependent gecko predatory impacts will be mediated by population demographics. We advocate further comparisons of functional responses to understand the invasiveness and future predatory impacts of geckos, and other invasive species globally, as temperatures change.
Collapse
Affiliation(s)
- Phillip J Haubrock
- Senckenberg Research Institute and Natural History Museum Frankfurt, Department of River Ecology and Conservation, Gelnhausen, Germany.
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, 389 25, Vodňany, Czech Republic.
| | - Ross N Cuthbert
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, Northern Ireland, UK
- GEOMAR, Helmholtz-Zentrum für Ozeanforschung Kiel, Düsternbrooker Weg 20, Kiel, Germany
| | - Lukáš Veselý
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, 389 25, Vodňany, Czech Republic
| | - Paride Balzani
- University of Florence, Department of Biology, Via Romana 17, 50121, Florence, Italy
| | - Nathan Jay Baker
- Senckenberg Research Institute and Natural History Museum Frankfurt, Department of River Ecology and Conservation, Gelnhausen, Germany
| | - Jaimie T A Dick
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, Northern Ireland, UK
| | - Antonín Kouba
- University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zátiší 728/II, 389 25, Vodňany, Czech Republic
| |
Collapse
|
20
|
Substrate mediated predator–prey interactions between invasive crayfish and indigenous and non-native amphipods. Biol Invasions 2020. [DOI: 10.1007/s10530-020-02292-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AbstractThe increasing number of taxa being translocated across the globe is leading to many non-native species encountering indigenous taxa as well as other non-native species. Environmental heterogeneity may strongly influence the spatial distribution, habitat use and refuge availability for these taxa. Using a series of 24-h mesocosm experiments we examined the predator–prey interactions between an invasive crayfish (Pacifastacus leniusculus) and four amphipod taxa, one indigenous (Gammarus pulex) and three non-native species (Crangonyx pseudogracilis, Dikerogammarus villosus and Gammarus tigrinus) to Great Britain. The potential mediating effect of physical habitat on predator–prey interactions was examined via the use of different substrate particle sizes; cobbles, gravels and, sand. Survivorship of amphipods in response to crayfish predation varied significantly with the highest rates recorded for the non-native species D. villosus, followed by G. tigrinus, and C. pseudogracilis, with the lowest survivorship recorded for the indigenous species G. pulex for all substrates except cobble. However, total biomass consumption of the indigenous G. pulex and the non-native D. villosus by P. leniusculus were similar suggesting that crayfish may have been satiated by larger D. villosus individuals. Substrate size had a significant influence on the predation success of P. leniusculus, with larger substrate clasts typically resulting in increased survivorship rates for all species except C. pseudogracilis, which displayed lower predation rates for sand substrates. The findings of this study highlight the risks that naïve indigenous taxa may face from new invasive species and the importance of characterising physical habitat (complexity and refugia potential) when considering the potential ecological effects of invaders on predation success.
Collapse
|
21
|
Buxton M, Cuthbert RN, Dalu T, Nyamukondiwa C, Wasserman RJ. Predator density modifies mosquito regulation in increasingly complex environments. PEST MANAGEMENT SCIENCE 2020; 76:2079-2086. [PMID: 31943746 DOI: 10.1002/ps.5746] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 12/16/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND Predation plays a pivotal role in the composition and functioning of ecosystems. Both habitat complexity and predator density are important contexts which may determine the strength of trophic and non-trophic interactions. In aquatic systems, the efficacy of natural enemies in regulating vector pest species could be modified by such context dependencies. Here, we use a functional response (FR) approach to experimentally quantify conspecific multiple predator effects across a habitat complexity gradient of two notonectids, Anisops sardea and Enithares chinai, towards larvae of the vector mosquito Culex pipiens pipiens. RESULTS E. chinai exhibited significantly greater consumption rates than A. sardea across habitat complexities, both as individuals and conspecific pairs. Each predator type displayed Type II FRs across experimental treatments, with synergistic multiple predator effects (i.e. prey risk enhancement) displayed in the absence of habitat complexity. Effects of increasing habitat complexity modified multiple predator effects differentially between species given behavioral differences, with habitat complexity causing significant antagonism (i.e. prey risk reduction) with multiple A. sardea compared to E. chinai. CONCLUSION Habitat complexity effects on multiple predator interactions can manifest differently at the species level, suggesting emergent effects which complicate predictions of natural enemy impact in heterogenous environments. Considerations of density, diversity and habitat effects on efficacies of natural enemies should thus be considered by pest management practitioners to better explain biocontrol efficacies in increasingly diverse environments. © 2020 Society of Chemical Industry.
Collapse
Affiliation(s)
- Mmabaledi Buxton
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana
| | - Ross N Cuthbert
- School of Biological Sciences, Queen's University Belfast, Belfast, UK
| | - Tatenda Dalu
- Department of Ecology and Resource Management, University of Venda, Thohoyandou, South Africa
| | - Casper Nyamukondiwa
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana
| | - Ryan J Wasserman
- Department of Biological Sciences and Biotechnology, Botswana International University of Science and Technology, Palapye, Botswana
| |
Collapse
|
22
|
Berardo C, Geritz S, Gyllenberg M, Raoul G. Interactions between different predator-prey states: a method for the derivation of the functional and numerical response. J Math Biol 2020; 80:2431-2468. [PMID: 32419034 PMCID: PMC7250814 DOI: 10.1007/s00285-020-01500-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 03/09/2020] [Indexed: 11/29/2022]
Abstract
In this paper we introduce a formal method for the derivation of a predator's functional response from a system of fast state transitions of the prey or predator on a time scale during which the total prey and predator densities remain constant. Such derivation permits an explicit interpretation of the structure and parameters of the functional response in terms of individual behaviour. The same method is also used here to derive the corresponding numerical response of the predator as well as of the prey.
Collapse
Affiliation(s)
- Cecilia Berardo
- Department of Mathematics and Statistics, University of Helsinki, 00014, Helsinki, Finland.
| | - Stefan Geritz
- Department of Mathematics and Statistics, University of Helsinki, 00014, Helsinki, Finland
| | - Mats Gyllenberg
- Department of Mathematics and Statistics, University of Helsinki, 00014, Helsinki, Finland
| | - Gaël Raoul
- Centre de Mathématiques Appliquées, École Polytechnique, 91128, Palaiseau Cedex, France
| |
Collapse
|
23
|
DeRoy EM, Scott R, Hussey NE, MacIsaac HJ. Density dependence mediates the ecological impact of an invasive fish. DIVERS DISTRIB 2020. [DOI: 10.1111/ddi.13063] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Emma M. DeRoy
- Great Lakes Institute for Environmental Research University of Windsor Windsor Ontario Canada
| | - Ryan Scott
- Department of Computer Science University of Windsor Windsor Ontario Canada
| | - Nigel E. Hussey
- Department of Biological Sciences University of Windsor Windsor Ontario Canada
| | - Hugh J. MacIsaac
- Great Lakes Institute for Environmental Research University of Windsor Windsor Ontario Canada
- School of Ecology and Environmental Science Yunnan University Kunming China
| |
Collapse
|
24
|
Dunn RP, Hovel KA. Predator type influences the frequency of functional responses to prey in marine habitats. Biol Lett 2020; 16:20190758. [PMID: 31964265 PMCID: PMC7013479 DOI: 10.1098/rsbl.2019.0758] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/05/2019] [Indexed: 01/02/2023] Open
Abstract
The functional response of a consumer to a gradient of resource density is a widespread and consistent framework used to quantify the importance of consumption to population dynamics and stability. Within benthic marine ecosystems, both crustaceans and fishes can provide strong top-down pressure on prey populations. Taxon-specific differences in biomechanics or habitat use, among other factors, may lead to variable functional response forms or parameter values (attack rate, handling time). Based on a review of 189 individual functional response fits, we find that these predator guilds differ in their frequency distribution of functional response types, with crustaceans exhibiting nearly double the proportion of sigmoidal, density-dependent functional responses (Holling type III) as predatory fishes. The implications of this finding for prey population stability are significant because type III responses allow prey persistence while type II responses are de-stabilizing and can lead to extinction. Comparing per capita predation rates across diverse taxa can provide integrative insights into predatory effects and the ability of predation to drive community structure.
Collapse
Affiliation(s)
- Robert P. Dunn
- Coastal and Marine Institute and Department of Biology, San Diego State University, San Diego, CA, USA
| | | |
Collapse
|
25
|
South J, McCard M, Khosa D, Mofu L, Madzivanzira TC, Dick JTA, Weyl OLF. The effect of prey identity and substrate type on the functional response of a globally invasive crayfish. NEOBIOTA 2019. [DOI: 10.3897/neobiota.52.39245] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Biological invasions threaten biodiversity on a global scale, therefore, developing predictive methods to understand variation in ecological change conferred is essential. Trophic interaction strength underpins community dynamics, however, these interactions can be profoundly affected by abiotic context, such as substrate type. The red swamp crayfish (Procambarus clarkii) has successfully invaded a number of freshwater ecosystems. We experimentally derive the Functional Response (FR) (density dependent predation) of the red swamp crayfish preying upon both a benthic prey; chironomid larvae, and a pelagic prey; Daphnia magna, on a no substrate control, sand, and gravel substrates to determine whether (1) there is a higher impact on prey that are benthic, and (2) whether the presence of different substrate types can dampen the interaction strength. We apply and demonstrate the utility of the Functional Response Ratio (FRR) metric in unravelling differences in ecological impact not obvious from traditional FR curves. Procambarus clarkii is capable of constantly utilising high numbers of both benthic and pelagic prey items, showing a Type II functional response under all scenarios. The presence of gravel and sand substrate each independently decreased the magnitude FR upon D. magna. Though, with regards to chironomid larvae the FR curves showed no difference in magnitude FR, the FRR reveals that the highest impact is conferred when foraging on sand substrate. This reinforces the need for impact assessments to be contextually relevant.
Collapse
|
26
|
Barrios-O'Neill D, Kelly R, Emmerson MC. Biomass encounter rates limit the size scaling of feeding interactions. Ecol Lett 2019; 22:1870-1878. [PMID: 31436021 PMCID: PMC6852157 DOI: 10.1111/ele.13380] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 05/06/2019] [Accepted: 08/01/2019] [Indexed: 11/30/2022]
Abstract
The rate that consumers encounter resources in space necessarily limits the strength of feeding interactions that shape ecosystems. To explore the link between encounters and feeding, we first compiled the largest available dataset of interactions in the marine benthos by extracting data from published studies and generating new data. These data indicate that the size-scaling of feeding interactions varies among consumer groups using different strategies (passive or active) to encounter different resource types (mobile or static), with filter feeders exhibiting the weakest feeding interactions. Next, we used these data to develop an agent-based model of resource biomass encounter rates, underpinned by consumer encounter strategy and resource biomass density. Our model demonstrates that passive strategies for encountering small, dispersed resources limits biomass encounter rates, necessarily limiting the strength of feeding interactions. Our model is based on generalisable assumptions, providing a framework to assess encounter-based drivers of consumption and coexistence across systems.
Collapse
Affiliation(s)
- Daniel Barrios-O'Neill
- Environment and Sustainability Institute, Penryn Campus, University of Exeter, Penryn, Cornwall, TR10 9EZ, UK.,School of Biological Sciences and Institute of Global Food Security, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, Northern Ireland
| | - Ruth Kelly
- School of Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
| | - Mark C Emmerson
- School of Biological Sciences and Institute of Global Food Security, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, Northern Ireland
| |
Collapse
|
27
|
Daugaard U, Petchey OL, Pennekamp F. Warming can destabilize predator–prey interactions by shifting the functional response from Type III to Type II. J Anim Ecol 2019; 88:1575-1586. [DOI: 10.1111/1365-2656.13053] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 05/10/2019] [Indexed: 11/27/2022]
Affiliation(s)
- Uriah Daugaard
- Institute of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
| | - Owen L. Petchey
- Institute of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
| | - Frank Pennekamp
- Institute of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
| |
Collapse
|
28
|
Effect of prey size and structural complexity on the functional response in a nematode- nematode system. Sci Rep 2019; 9:5696. [PMID: 30952927 PMCID: PMC6451004 DOI: 10.1038/s41598-019-42213-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/25/2019] [Indexed: 11/09/2022] Open
Abstract
The functional response of a predatory nematode and the influence of different prey sizes and habitat structure on the concerning parameters were analyzed. We hypothesized that the handling of small prey would be less time-consuming, whereas feeding on larger prey would be more efficient. Therefore, type II functional response curves were expected for large prey and a trend towards type III curves for small prey. We expected the introduction of prey refuges to shift the functional response curves from hyperbolic to sigmoidal and that the effect would be even more pronounced with smaller prey. P. muscorum consumed large amounts of small and large C. elegans, with daily per capita ingestion of prey reaching a maximum of 19.8 µg fresh weight, which corresponds to 4.8 times the predator’s biomass. Regardless of prey size and habitat structure, P. muscorum exhibit a type III functional response. Overall, the allometric effect of prey size had a greater effect on the predator’s functional response than did the addition of substrate, presumably due to the similar body shape and mobility of the two nematode species. Our results demonstrate that individual factors such as feeding behavior are important determinants of functional responses and therefore of ecosystem stability.
Collapse
|
29
|
|
30
|
Marler TE, Marler PN. Rhyzobius lophanthae Behavior is Influenced by Cycad Plant Age, Providing Odor Samples in a Y-tube Olfactometer. INSECTS 2018; 9:insects9040194. [PMID: 30567297 PMCID: PMC6315894 DOI: 10.3390/insects9040194] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/12/2018] [Accepted: 12/17/2018] [Indexed: 12/02/2022]
Abstract
The scale predator Rhyzobius lophanthae Blaisdell was introduced to Guam and Rota to control invasive Aulacaspis yasumatsui Takagi armored scale infestations on the native Cycas micronesica K.D. Hill populations. The predator demonstrated a clear preference for A. yasumatsui infesting adult plants, resulting in 100% seedling mortality due to the lack of a biocontrol of the scale on seedlings. A Y-tube olfactometer was employed to determine if scale-infested seedling leaves were less attractive to R. lophanthae than scale-infested mature tree leaves. Five paired combinations of seedling versus mature tree leaves were used. The R. lophanthae adults navigated toward scale-infested and un-infested leaves of adults and seedlings when paired with an empty chamber. However, a clear preference for adult leaves occurred when paired with seedling leaves. The results were unambiguous in charcoal-filtered air, intermediate in unfiltered air from an open laboratory, and most ambiguous when conducted with unfiltered in-situ air. The number of predators that did not make a choice was greatest for in-situ air and least for charcoal-filtered air. These results indicated that the substrate used in olfactometry influenced the results, and interpretations of charcoal-filtered air assays should be made with caution. Volatile chemical cues are involved in R. lophanthae preferring A. yasumatsui located on C. micronesica adults when infested adult and seedling leaves are present.
Collapse
Affiliation(s)
- Thomas E Marler
- College of Natural and Applied Sciences, University of Guam, UOG Station, Mangilao, Guam 96923, USA.
| | - Paris N Marler
- Centre for Sustainability PH, Inc., PENRO Road, Puerto Princesa, Palawan 5300, Philippines.
| |
Collapse
|
31
|
Thorp CJ, Alexander ME, Vonesh JR, Measey J. Size-dependent functional response of Xenopus laevis feeding on mosquito larvae. PeerJ 2018; 6:e5813. [PMID: 30386704 PMCID: PMC6204824 DOI: 10.7717/peerj.5813] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 09/21/2018] [Indexed: 11/29/2022] Open
Abstract
Predators can play an important role in regulating prey abundance and diversity, determining food web structure and function, and contributing to important ecosystem services, including the regulation of agricultural pests and disease vectors. Thus, the ability to predict predator impact on prey is an important goal in ecology. Often, predators of the same species are assumed to be functionally equivalent, despite considerable individual variation in predator traits known to be important for shaping predator–prey interactions, like body size. This assumption may greatly oversimplify our understanding of within-species functional diversity and undermine our ability to predict predator effects on prey. Here, we examine the degree to which predator–prey interactions are functionally homogenous across a natural range of predator body sizes. Specifically, we quantify the size-dependence of the functional response of African clawed frogs (Xenopus laevis) preying on mosquito larvae (Culex pipiens). Three size classes of predators, small (15–30 mm snout-vent length), medium (50–60 mm) and large (105–120 mm), were presented with five densities of prey to determine functional response type and to estimate search efficiency and handling time parameters generated from the models. The results of mesocosm experiments showed that type of functional response of X. laevis changed with size: small predators exhibited a Type II response, while medium and large predators exhibited Type III responses. Functional response data showed an inversely proportional relationship between predator attack rate and predator size. Small and medium predators had highest and lowest handling time, respectively. The change in functional response with the size of predator suggests that predators with overlapping cohorts may have a dynamic impact on prey populations. Therefore, predicting the functional response of a single size-matched predator in an experiment may misrepresent the predator’s potential impact on a prey population.
Collapse
Affiliation(s)
- Corey J Thorp
- Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Stellenbosch, South Africa
| | - Mhairi E Alexander
- Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Stellenbosch, South Africa.,Institute for Biomedical and Environmental Health Research (IBEHR), School of Health and Life Sciences, University of the West of Scotland, Paisley, UK
| | - James R Vonesh
- Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Stellenbosch, South Africa.,Department of Biology, Virginia Commonwealth University, Richmond, VA, USA.,Center for Environmental Studies, Virginia Commonwealth University, Richmond, VA, USA
| | - John Measey
- Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Stellenbosch, South Africa
| |
Collapse
|
32
|
Bertolini C, Montgomery WI, O’Connor NE. Habitat with small inter-structural spaces promotes mussel survival and reef generation. MARINE BIOLOGY 2018; 165:163. [PMID: 30363846 PMCID: PMC6182589 DOI: 10.1007/s00227-018-3426-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 09/28/2018] [Indexed: 05/21/2023]
Abstract
Spatially complex habitats provide refuge for prey and mediate many predator-prey interactions. Increasing anthropogenic pressures are eroding such habitats, reducing their complexity and potentially altering ecosystem stability on a global scale. Yet, we have only a rudimentary understanding of how structurally complex habitats create ecological refuges for most ecosystems. Better informed management decisions require an understanding of the mechanisms underpinning the provision of physical refuge and this may be linked to prey size, predator size and predator identity in priority habitats. We tested each of these factors empirically in a model biogenic reef system. Specifically, we tested whether mortality rates of blue mussels (Mytilus edulis) of different sizes differed among: (i) different forms of reef structural distribution (represented as 'clumped', 'patchy' and 'sparse'); (ii) predator species identity (shore crab, Carcinus maenas and starfish, Asterias rubens); and (iii) predator size. The survival rate of small mussels was greatest in the clumped experimental habitat and larger predators generally consumed more prey regardless of the structural organisation of treatment. Small mussels were protected from larger A. rubens but not from larger C. maenas in the clumped habitats. The distribution pattern of structural objects, therefore, may be considered a useful proxy for reef complexity when assessing predator-prey interactions, and optimal organisations should be considered based on both prey and predator sizes. These findings are essential to understand ecological processes underpinning predation rates in structurally complex habitats and to inform future restoration and ecological engineering practices.
Collapse
Affiliation(s)
- Camilla Bertolini
- School of Biological Sciences, Queen’s University of Belfast, 97 Lisburn Road, Belfast, BT9 7BL Northern Ireland, UK
- NIOZ Royal Netherlands Institute for Sea Research, Department of Estuarine and Delta Systems, Utrecht University, PO Box 140, 4401 NT Yerseke, The Netherlands
| | - W. I. Montgomery
- School of Biological Sciences, Queen’s University of Belfast, 97 Lisburn Road, Belfast, BT9 7BL Northern Ireland, UK
| | - Nessa E. O’Connor
- School of Biological Sciences, Queen’s University of Belfast, 97 Lisburn Road, Belfast, BT9 7BL Northern Ireland, UK
- School of Natural Sciences, Zoology Building, Trinity College Dublin, Dublin 2, Ireland
| |
Collapse
|
33
|
Rosenbaum B, Rall BC. Fitting functional responses: Direct parameter estimation by simulating differential equations. Methods Ecol Evol 2018. [DOI: 10.1111/2041-210x.13039] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Benjamin Rosenbaum
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
- Institute of BiodiversityFriedrich Schiller University Jena Jena Germany
| | - Björn C. Rall
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
- Institute of BiodiversityFriedrich Schiller University Jena Jena Germany
- Department of Aquatic EcologyNetherlands Institute of Ecology (NIOO‐KNAW) Wageningen The Netherlands
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW) Wageningen The Netherlands
| |
Collapse
|
34
|
Predatory impacts of alien decapod Crustacea are predicted by functional responses and explained by differences in metabolic rate. Biol Invasions 2018. [DOI: 10.1007/s10530-018-1735-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
35
|
Eitzinger B, Rall BC, Traugott M, Scheu S. Testing the validity of functional response models using molecular gut content analysis for prey choice in soil predators. OIKOS 2018. [DOI: 10.1111/oik.04885] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Bernhard Eitzinger
- J. F. Blumenbach Inst. of Zoology and Anthropology; Univ. of Göttingen; Untere Karspüle 2 DE-37073 Göttingen Germany
- Dept of Agricultural Sciences; Univ. of Helsinki; Helsinki Finland
| | - Björn C. Rall
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig; Leipzig Germany
- Inst. of Biodiversity, Friedrich Schiller Univ. Jena; Jena Germany
| | - Michael Traugott
- Mountain Agriculture Research Unit; Inst. of Ecology, Univ. of Innsbruck; Innsbruck Austria
| | - Stefan Scheu
- J. F. Blumenbach Inst. of Zoology and Anthropology; Univ. of Göttingen; Untere Karspüle 2 DE-37073 Göttingen Germany
- Centre of Biodiversity and Sustainable Land Use; Univ. of Göttingen; Göttingen Germany
| |
Collapse
|
36
|
South J, Welsh D, Anton A, Sigwart JD, Dick JTA. Increasing temperature decreases the predatory effect of the intertidal shanny Lipophrys pholis on an amphipod prey. JOURNAL OF FISH BIOLOGY 2018; 92:150-164. [PMID: 29139120 DOI: 10.1111/jfb.13500] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 10/04/2017] [Indexed: 06/07/2023]
Abstract
Interactions between Lipophrys pholis and its amphipod prey Echinogammarus marinus were used to investigate the effect of changing water temperatures, comparing current and predicted mean summer temperatures. Contrary to expectations, predator attack rates significantly decreased with increasing temperature. Handling times were significantly longer at 19° C than at 17 and 15° C and the maximum feeding estimate was significantly lower at 19° C than at 17° C. Functional-response type changed from a destabilizing type II to the more stabilizing type III with a temperature increase to 19° C. This suggests that a temperature increase can mediate refuge for prey at low densities. Predatory pressure by teleosts may be dampened by a large increase in temperature (here from 15 to 19° C), but a short-term and smaller temperature increase (to 17° C) may increase destabilizing resource consumption due to high maximum feeding rates; this has implications for the stability of important intertidal ecosystems during warming events.
Collapse
Affiliation(s)
- J South
- Queen's University Marine Laboratory, Queen's University Belfast, 12-13 The Strand, Portaferry, BT22 1LS, U.K
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, MBC, 97 Lisburn Road, Belfast, U.K
| | - D Welsh
- Queen's University Marine Laboratory, Queen's University Belfast, 12-13 The Strand, Portaferry, BT22 1LS, U.K
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, MBC, 97 Lisburn Road, Belfast, U.K
| | - A Anton
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, 23955-6900, Saudi Arabia
| | - J D Sigwart
- Queen's University Marine Laboratory, Queen's University Belfast, 12-13 The Strand, Portaferry, BT22 1LS, U.K
- University of California Museum of Paleontology, University of California, Berkeley, VLSB 1101, Berkeley, CA, 94720, U.S.A
| | - J T A Dick
- Queen's University Marine Laboratory, Queen's University Belfast, 12-13 The Strand, Portaferry, BT22 1LS, U.K
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, MBC, 97 Lisburn Road, Belfast, U.K
| |
Collapse
|
37
|
Effects of prey density, temperature and predator diversity on nonconsumptive predator-driven mortality in a freshwater food web. Sci Rep 2017; 7:18075. [PMID: 29273716 PMCID: PMC5741715 DOI: 10.1038/s41598-017-17998-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 12/05/2017] [Indexed: 11/08/2022] Open
Abstract
Nonconsumptive predator-driven mortality (NCM), defined as prey mortality due to predation that does not result in prey consumption, is an underestimated component of predator-prey interactions with possible implications for population dynamics and ecosystem functioning. However, the biotic and abiotic factors influencing this mortality component remain largely unexplored, leaving a gap in our understanding of the impacts of environmental change on ecological communities. We investigated the effects of temperature, prey density, and predator diversity and density on NCM in an aquatic food web module composed of dragonfly larvae (Aeshna cyanea) and marbled crayfish (Procambarus fallax f. virginalis) preying on common carp (Cyprinus carpio) fry. We found that NCM increased with prey density and depended on the functional diversity and density of the predator community. Warming significantly reduced NCM only in the dragonfly larvae but the magnitude depended on dragonfly larvae density. Our results indicate that energy transfer across trophic levels is more efficient due to lower NCM in functionally diverse predator communities, at lower resource densities and at higher temperatures. This suggests that environmental changes such as climate warming and reduced resource availability could increase the efficiency of energy transfer in food webs only if functionally diverse predator communities are conserved.
Collapse
|
38
|
Médoc V, Thuillier L, Spataro T. Opportunistic omnivory impairs our ability to predict invasive species impacts from functional response comparisons. Biol Invasions 2017. [DOI: 10.1007/s10530-017-1628-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
39
|
Parasitism may alter functional response comparisons: a case study on the killer shrimp Dikerogammarus villosus and two non-invasive gammarids. Biol Invasions 2017. [DOI: 10.1007/s10530-017-1563-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
40
|
Penk M, Saul W, Dick JT, Donohue I, Alexander ME, Linzmaier S, Jeschke JM. A trophic interaction framework for identifying the invasive capacity of novel organisms. Methods Ecol Evol 2017. [DOI: 10.1111/2041-210x.12817] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marcin Penk
- School of Natural SciencesTrinity College Dublin Dublin Ireland
- Department of Biology, Chemistry, PharmacyInstitute of BiologyFreie Universität Berlin Berlin Germany
| | - Wolf‐Christian Saul
- Department of Biology, Chemistry, PharmacyInstitute of BiologyFreie Universität Berlin Berlin Germany
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB) Berlin Germany
- Berlin‐Brandenburg Institute of Advanced Biodiversity Research (BBIB) Berlin Germany
- Centre for Invasion Biology (CIB)Department of Botany and Zoology & Department of Mathematical SciencesStellenbosch University Matieland South Africa
| | - Jaimie T.A. Dick
- Institute for Global Food SecuritySchool of Biological SciencesQueen's University Belfast Belfast UK
| | - Ian Donohue
- School of Natural SciencesTrinity College Dublin Dublin Ireland
| | - Mhairi E. Alexander
- Institute for Biomedical and Environmental Health Research (IBEHR)School of Science and SportUniversity of the West of Scotland Paisley UK
| | - Stefan Linzmaier
- Department of Biology, Chemistry, PharmacyInstitute of BiologyFreie Universität Berlin Berlin Germany
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB) Berlin Germany
- Berlin‐Brandenburg Institute of Advanced Biodiversity Research (BBIB) Berlin Germany
| | - Jonathan M. Jeschke
- Department of Biology, Chemistry, PharmacyInstitute of BiologyFreie Universität Berlin Berlin Germany
- Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB) Berlin Germany
- Berlin‐Brandenburg Institute of Advanced Biodiversity Research (BBIB) Berlin Germany
| |
Collapse
|
41
|
Pritchard DW, Paterson RA, Bovy HC, Barrios‐O'Neill D. frair
: an R package for fitting and comparing consumer functional responses. Methods Ecol Evol 2017. [DOI: 10.1111/2041-210x.12784] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Daniel W. Pritchard
- Department of Marine Sciences University of Otago PO Box 56 Dunedin 9054 New Zealand
- Te Ao Tūroa, Te Rūnanga o Ngāi Tahu Dunedin 9054 New Zealand
| | - Rachel A. Paterson
- School of Biological Sciences Queen's University Belfast Belfast BT9 7LB UK
- School of Biosciences Cardiff University Cardiff CF10 3AX UK
| | - Helene C. Bovy
- School of Biological Sciences Queen's University Belfast Belfast BT9 7LB UK
| | - Daniel Barrios‐O'Neill
- School of Biological Sciences Queen's University Belfast Belfast BT9 7LB UK
- Centre for Ecology & Conservation Penryn Campus University of Exeter Penryn Cornwall TR10 9EZ UK
| |
Collapse
|
42
|
Assessing the ecological impacts of invasive species based on their functional responses and abundances. Biol Invasions 2017. [DOI: 10.1007/s10530-017-1378-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
43
|
Hesterberg SG, Duckett CC, Salewski EA, Bell SS. Three-dimensional interstitial space mediates predator foraging success in different spatial arrangements. Ecology 2017; 98:1153-1162. [PMID: 28144935 DOI: 10.1002/ecy.1762] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 11/14/2016] [Accepted: 01/24/2017] [Indexed: 11/11/2022]
Abstract
Identifying and quantifying the relevant properties of habitat structure that mediate predator-prey interactions remains a persistent challenge. Most previous studies investigate effects of structural density on trophic interactions and typically quantify refuge quality using one or two-dimensional metrics. Few consider spatial arrangement of components (i.e., orientation and shape) and often neglect to measure the total three-dimensional (3D) space available as refuge. This study tests whether the three-dimensionality of interstitial space, an attribute produced by the spatial arrangement of oyster (Crassostrea virginica) shells, impacts the foraging success of nektonic predators (primary blue crab, Callinectes sapidus) on mud crab prey (Eurypanopeus depressus) in field and mesocosm experiments. Interstices of 3D-printed shell mimics were manipulated by changing either their orientation (angle) or internal shape (crevice or channel). In both field and mesocosm experiments, under conditions of constant structural density, predator foraging success was influenced by 3D aspects of interstitial space. Proportional survivorship of tethered mud crabs differed significantly as 3D interstitial space varied by orientation, displaying decreasing prey survivorship as angle of orientation increased (0° = 0.76, 22.5° = 0.13, 45° = 0.0). Tethered prey survivorship was high when 3D interstitial space of mimics was modified by internal shape (crevice survivorship = 0.89, channel survivorship = 0.96) and these values did not differ significantly. In mesocosms, foraging success of blue crabs varied with 3D interstitial space as mean proportional survivorship (± SE) of mud crabs was significantly lower in 45° (0.27 ± 0.06) vs. 0° (0.86 ± 0.04) orientations and for crevice (0.52 ± 0.11) vs. channel shapes (0.95 ± 0.02). These results suggest that 3D aspects of interstitial space, which have direct relevance to refuge quality, can strongly influence foraging success in our oyster reef habitat. Our findings highlight the importance of spatial arrangement in mediating consumptive pathways in hard-structured habitats and demonstrate how quantifying the three-dimensionality of living space captures aspects of habitat structure that have been missing from previous empirical studies of trophic interactions and structural complexity.
Collapse
Affiliation(s)
- Stephen G Hesterberg
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Ave, SCA 110, Tampa, Florida, 33620, USA
| | - C Cole Duckett
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Ave, SCA 110, Tampa, Florida, 33620, USA
| | - Elizabeth A Salewski
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Ave, SCA 110, Tampa, Florida, 33620, USA
| | - Susan S Bell
- Department of Integrative Biology, University of South Florida, 4202 East Fowler Ave, SCA 110, Tampa, Florida, 33620, USA
| |
Collapse
|
44
|
Dick JT, Laverty C, Lennon JJ, Barrios-O'Neill D, Mensink PJ, Robert Britton J, Médoc V, Boets P, Alexander ME, Taylor NG, Dunn AM, Hatcher MJ, Rosewarne PJ, Crookes S, MacIsaac HJ, Xu M, Ricciardi A, Wasserman RJ, Ellender BR, Weyl OL, Lucy FE, Banks PB, Dodd JA, MacNeil C, Penk MR, Aldridge DC, Caffrey JM. Invader Relative Impact Potential: a new metric to understand and predict the ecological impacts of existing, emerging and future invasive alien species. J Appl Ecol 2017. [DOI: 10.1111/1365-2664.12849] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Jaimie T.A. Dick
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; MBC, 97 Lisburn Road Belfast BT9 7BL UK
| | - Ciaran Laverty
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; MBC, 97 Lisburn Road Belfast BT9 7BL UK
| | - Jack J. Lennon
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; MBC, 97 Lisburn Road Belfast BT9 7BL UK
| | - Daniel Barrios-O'Neill
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; MBC, 97 Lisburn Road Belfast BT9 7BL UK
| | - Paul J. Mensink
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; MBC, 97 Lisburn Road Belfast BT9 7BL UK
| | - J. Robert Britton
- Department of Life and Environmental Sciences; Faculty of Science and Technology; Bournemouth University; Fern Barrow, Poole Dorset BH12 5BB UK
| | - Vincent Médoc
- Institute of Ecology and Environmental Sciences; Université Pierre et Marie Curie (Paris 6); 75005 Paris France
| | - Pieter Boets
- Provinciaal Centrum voor Milieuonderzoek; Godshuizenlaan 95 9000 Ghent Belgium
| | - Mhairi E. Alexander
- Institute for Biomedical and Environmental Health Research (IBEHR); School of Science and Sport; University of the West of Scotland; Paisley PA1 2BE UK
| | - Nigel G. Taylor
- School of Biology; Faculty of Biological Sciences; University of Leeds; Leeds LS2 9JT UK
| | - Alison M. Dunn
- School of Biology; Faculty of Biological Sciences; University of Leeds; Leeds LS2 9JT UK
| | - Melanie J. Hatcher
- School of Biology; Faculty of Biological Sciences; University of Leeds; Leeds LS2 9JT UK
| | - Paula J. Rosewarne
- School of Biology; Faculty of Biological Sciences; University of Leeds; Leeds LS2 9JT UK
| | - Steven Crookes
- Great Lakes Institute for Environmental Research; University of Windsor; Windsor ON N9B 3P4 Canada
| | - Hugh J. MacIsaac
- Great Lakes Institute for Environmental Research; University of Windsor; Windsor ON N9B 3P4 Canada
| | - Meng Xu
- Pearl River Fisheries Research Institute; Chinese Academy of Fishery Sciences; Key Laboratory of Tropical and Subtropical Fishery Resource Application and Cultivation; Ministry of Agriculture; Guangzhou 510380 China
| | - Anthony Ricciardi
- Redpath Museum; McGill University; 859 Sherbrooke Street West Montreal QC H3A 0C4 Canada
| | - Ryan J. Wasserman
- South African Institute for Aquatic Biodiversity (SAIAB); P. Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology; South African Institute for Aquatic Biodiversity (SAIAB); P. Bag 1015 Grahamstown 6140 South Africa
| | - Bruce R. Ellender
- South African Institute for Aquatic Biodiversity (SAIAB); P. Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology; South African Institute for Aquatic Biodiversity (SAIAB); P. Bag 1015 Grahamstown 6140 South Africa
| | - Olaf L.F. Weyl
- South African Institute for Aquatic Biodiversity (SAIAB); P. Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology; South African Institute for Aquatic Biodiversity (SAIAB); P. Bag 1015 Grahamstown 6140 South Africa
| | - Frances E. Lucy
- Department of Life and Environmental Sciences; Faculty of Science and Technology; Bournemouth University; Fern Barrow, Poole Dorset BH12 5BB UK
- Centre for Environmental Research, Innovation & Sustainability; Institute of Technology Sligo; Ash Lane, Co. Sligo Ireland
| | - Peter B. Banks
- School of Life and Environmental Sciences; The University of Sydney; Science Road Cottage A10 Camperdown NSW 2006 Australia
| | - Jennifer A. Dodd
- Scottish Centre for Ecology & the Natural Environment; IBAHCM; University of Glasgow; Rowardennan Glasgow G63 0AW UK
| | - Calum MacNeil
- Department of Environment, Food and Agriculture; This Slieau Whallian; Foxdale Road St. Johns IM4 3AS Isle of Man
| | - Marcin R. Penk
- Department of Zoology; School of Natural Sciences; Trinity College Dublin; Dublin 2 Ireland
| | - David C. Aldridge
- Department of Zoology; University of Cambridge; David Attenborough Building, Downing Street Cambridge CB2 3EJ UK
| | - Joseph M. Caffrey
- Department of Life and Environmental Sciences; Faculty of Science and Technology; Bournemouth University; Fern Barrow, Poole Dorset BH12 5BB UK
- INVAS Biosecurity; 6 Lower Ballymount Road, Walkinstown Dublin 12 Ireland
| |
Collapse
|
45
|
Jackson M, Wasserman R, Grey J, Ricciardi A, Dick J, Alexander M. Novel and Disrupted Trophic Links Following Invasion in Freshwater Ecosystems. ADV ECOL RES 2017. [DOI: 10.1016/bs.aecr.2016.10.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
|
46
|
Size matters: predation of fish eggs and larvae by native and invasive amphipods. Biol Invasions 2017; 19:89-107. [PMID: 32355455 PMCID: PMC7175601 DOI: 10.1007/s10530-016-1265-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 08/26/2016] [Indexed: 10/24/2022]
Abstract
Invasive predators can have dramatic impacts on invaded communities. Extreme declines in macroinvertebrate populations often follow killer shrimp (Dikerogammarus villosus) invasions. There are concerns over similar impacts on fish through predation of eggs and larvae, but these remain poorly quantified. We compare the predatory impact of invasive and native amphipods (D. villosus and Gammarus pulex) on fish eggs and larvae (ghost carp Cyprinus carpio and brown trout Salmo trutta) in the laboratory. We use size-matched amphipods, as well as larger D. villosus reflecting natural sizes. We quantify functional responses, and electivity amongst eggs or larvae and alternative food items (invertebrate, plant and decaying leaf). D. villosus, especially large individuals, were more likely than G. pulex to kill trout larvae. However, the magnitude of predation was low (seldom more than one larva killed over 48 h). Trout eggs were very rarely killed. In contrast, carp eggs and larvae were readily killed and consumed by all amphipod groups. Large D. villosus had maximum feeding rates 1.6-2.0 times higher than the smaller amphipods, whose functional responses did not differ. In electivity experiments with carp eggs, large D. villosus consumed the most eggs and the most food in total. However, in experiments with larvae, consumption did not differ between amphipod groups. Overall, our data suggest D. villosus will have a greater predatory impact on fish populations than G. pulex, primarily due to its larger size. Higher invader abundance could amplify this difference. The additional predatory pressure could reduce recruitment into fish populations.
Collapse
|
47
|
Wasserman RJ, Alexander ME, Dalu T, Ellender BR, Kaiser H, Weyl OLF. Using functional responses to quantify interaction effects among predators. Funct Ecol 2016. [DOI: 10.1111/1365-2435.12682] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ryan J. Wasserman
- South African Institute for Aquatic Biodiversity (SAIAB) P. Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology South African Institute for Aquatic Biodiversity (SAIAB) P. Bag 1015 Grahamstown 6140 South Africa
| | - Mhairi E. Alexander
- Centre for Invasion Biology South African Institute for Aquatic Biodiversity (SAIAB) P. Bag 1015 Grahamstown 6140 South Africa
- Institute for Biomedical and Environmental Health Research (IBEHR) School of Science and Sport University of the West of Scotland Paisley PA1 2BE ScotlandUK
- Department of Botany and Zoology Centre for Invasion Biology Stellenbosch University Matieland 7602 South Africa
| | - Tatenda Dalu
- Department of Zoology and Entomology Rhodes University P.O. Box 94 Grahamstown 6140 South Africa
| | - Bruce R. Ellender
- South African Institute for Aquatic Biodiversity (SAIAB) P. Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology South African Institute for Aquatic Biodiversity (SAIAB) P. Bag 1015 Grahamstown 6140 South Africa
| | - Horst Kaiser
- Department of Ichthyology and Fisheries Science Rhodes University P.O. Box 94 Grahamstown 6140 South Africa
| | - Olaf L. F. Weyl
- South African Institute for Aquatic Biodiversity (SAIAB) P. Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology South African Institute for Aquatic Biodiversity (SAIAB) P. Bag 1015 Grahamstown 6140 South Africa
- Department of Ichthyology and Fisheries Science Rhodes University P.O. Box 94 Grahamstown 6140 South Africa
| |
Collapse
|
48
|
Barrios-O'Neill D, Kelly R, Dick JTA, Ricciardi A, MacIsaac HJ, Emmerson MC. On the context-dependent scaling of consumer feeding rates. Ecol Lett 2016; 19:668-78. [DOI: 10.1111/ele.12605] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 02/23/2016] [Accepted: 03/11/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Daniel Barrios-O'Neill
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; 97 Lisburn Road Belfast BT9 7BL Northern Ireland
| | - Ruth Kelly
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; 97 Lisburn Road Belfast BT9 7BL Northern Ireland
| | - Jaimie T. A. Dick
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; 97 Lisburn Road Belfast BT9 7BL Northern Ireland
| | - Anthony Ricciardi
- Redpath Museum; McGill University; 859 Sherbrooke Street West Montreal QC H3AOC4 Canada
| | - Hugh J. MacIsaac
- Great Lakes Institute for Environmental Research; University of Windsor; Windsor ON N9B 3P4 Canada
| | - Mark C. Emmerson
- Institute for Global Food Security; School of Biological Sciences; Queen's University Belfast; 97 Lisburn Road Belfast BT9 7BL Northern Ireland
| |
Collapse
|
49
|
Wasserman RJ, Alexander ME, Weyl OLF, Barrios-O'Neill D, Froneman PW, Dalu T. Emergent effects of structural complexity and temperature on predator-prey interactions. Ecosphere 2016. [DOI: 10.1002/ecs2.1239] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Ryan J. Wasserman
- South African Institute for Aquatic Biodiversity (SAIAB); Private Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology; South African Institute for Aquatic Biodiversity (SAIAB); Private Bag 1015 Grahamstown 6140 South Africa
| | - Mhairi E. Alexander
- Department of Botany and Zoology; Centre for Invasion Biology; Stellenbosch University; Matieland 7602 South Africa
| | - Olaf L. F. Weyl
- South African Institute for Aquatic Biodiversity (SAIAB); Private Bag 1015 Grahamstown 6140 South Africa
- Centre for Invasion Biology; South African Institute for Aquatic Biodiversity (SAIAB); Private Bag 1015 Grahamstown 6140 South Africa
| | - Daniel Barrios-O'Neill
- Institute for Global Food Security; School of Biological Sciences; Queens University Belfast; 97 Lisburn Road Belfast BT9 7BL UK
| | - P. William Froneman
- Department of Zoology and Entomology; Rhodes University; P.O. Box 94 Grahamstown 6140 South Africa
| | - Tatenda Dalu
- Department of Zoology and Entomology; Rhodes University; P.O. Box 94 Grahamstown 6140 South Africa
| |
Collapse
|
50
|
Comparative Functional Responses Predict the Invasiveness and Ecological Impacts of Alien Herbivorous Snails. PLoS One 2016; 11:e0147017. [PMID: 26771658 PMCID: PMC4714930 DOI: 10.1371/journal.pone.0147017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 12/27/2015] [Indexed: 11/23/2022] Open
Abstract
Understanding determinants of the invasiveness and ecological impacts of alien species is amongst the most sought-after and urgent research questions in ecology. Several studies have shown the value of comparing the functional responses (FRs) of alien and native predators towards native prey, however, the technique is under-explored with herbivorous alien species and as a predictor of invasiveness as distinct from ecological impact. Here, in China, we conducted a mesocosm experiment to compare the FRs among three herbivorous snail species: the golden apple snail, Pomacea canaliculata, a highly invasive and high impact alien listed in “100 of the World's Worst Invasive Alien Species”; Planorbarius corneus, a non-invasive, low impact alien; and the Chinese native snail, Bellamya aeruginosa, when feeding on four locally occurring plant species. Further, by using a numerical response equation, we modelled the population dynamics of the snail consumers. For standard FR parameters, we found that the invasive and damaging alien snail had the highest “attack rates” a, shortest “handling times” h and also the highest estimated maximum feeding rates, 1/hT, whereas the native species had the lowest attack rates, longest handling times and lowest maximum feeding rates. The non-invasive, low impact alien species had consistently intermediate FR parameters. The invasive alien species had higher population growth potential than the native snail species, whilst that of the non-invasive alien species was intermediate. Thus, while the comparative FR approach has been proposed as a reliable method for predicting the ecological impacts of invasive predators, our results further suggest that comparative FRs could extend to predict the invasiveness and ecological impacts of alien herbivores and should be explored in other taxa and trophic groups to determine the general utility of the approach.
Collapse
|