The Experts below are selected from a list of 38622 Experts worldwide ranked by ideXlab platform
G. M. Ruiz - One of the best experts on this subject based on the ideXlab platform.
-
Coarse woody debris as a refuge from predation in Aquatic Communities
Oecologia, 1993Co-Authors: R. A. Everett, G. M. RuizAbstract:This study demonstrates experimentally that coarse woody debris (CWD) can provide refuge from predation in Aquatic habitats. In the Rhode River subestuary of Chesapeake Bay, Maryland, (USA), we (1) measured the abundance of CWD, (2) examined the utilization of CWD by mobile epibenthic fish and crustaceans, and (3) tested experimentally the value of CWD as a refuge from predation. CWD was the dominant above-bottom physical structure in shallow water, ranging in size from small branches (50 cm diameter). In response to experimental additions of CWD, densities of common epibenthic cpecies ( Callinectes sapidus, Fundulus heteroclitus, Fundulus majalis, Gobiosoma bosc, Gobiesox strumosus, Palaemonetes pugio , and Rithropanopeus harrisii ) increased significantly compared to control sites without CWD. In laboratory experiments, grass shrimp ( P. pugio ) responded to predatory fish ( F. heteroclitus and Micropogonias undulatus ) by utilizing shelter at CWD more frequently than in absence of fish. Access to CWD increased survivorship of grass shrimp in laboratory and field experiments. These experimental results (1) support the hypothesis, commonly proposed but untested for freshwater habitats, that CWD can provide a refuge from predation for epibenthic fish and invertebrates and (2) extend the recognized functional importance of CWD in freshwater to estuarine and marine Communities. We hypothesize that CWD is an especially important refuge habitat in the many estuarine and freshwater systems for which alternative physical structure (e.g., vegetation or oyster reefs) are absent or in low abundance.
-
coarse woody debris as a refuge from predation in Aquatic Communities an experimental test
Oecologia, 1993Co-Authors: R. A. Everett, G. M. RuizAbstract:This study demonstrates experimentally that coarse woody debris (CWD) can provide refuge from predation in Aquatic habitats. In the Rhode River subestuary of Chesapeake Bay, Maryland, (USA), we (1) measured the abundance of CWD, (2) examined the utilization of CWD by mobile epibenthic fish and crustaceans, and (3) tested experimentally the value of CWD as a refuge from predation. CWD was the dominant above-bottom physical structure in shallow water, ranging in size from small branches ( 50 cm diameter). In response to experimental additions of CWD, densities of common epibenthic cpecies (Callinectes sapidus, Fundulus heteroclitus, Fundulus majalis, Gobiosoma bosc, Gobiesox strumosus, Palaemonetes pugio, and Rithropanopeus harrisii) increased significantly compared to control sites without CWD. In laboratory experiments, grass shrimp (P. pugio) responded to predatory fish (F. heteroclitus and Micropogonias undulatus) by utilizing shelter at CWD more frequently than in absence of fish. Access to CWD increased survivorship of grass shrimp in laboratory and field experiments. These experimental results (1) support the hypothesis, commonly proposed but untested for freshwater habitats, that CWD can provide a refuge from predation for epibenthic fish and invertebrates and (2) extend the recognized functional importance of CWD in freshwater to estuarine and marine Communities. We hypothesize that CWD is an especially important refuge habitat in the many estuarine and freshwater systems for which alternative physical structure (e.g., vegetation or oyster reefs) are absent or in low abundance.
R. A. Everett - One of the best experts on this subject based on the ideXlab platform.
-
Coarse woody debris as a refuge from predation in Aquatic Communities
Oecologia, 1993Co-Authors: R. A. Everett, G. M. RuizAbstract:This study demonstrates experimentally that coarse woody debris (CWD) can provide refuge from predation in Aquatic habitats. In the Rhode River subestuary of Chesapeake Bay, Maryland, (USA), we (1) measured the abundance of CWD, (2) examined the utilization of CWD by mobile epibenthic fish and crustaceans, and (3) tested experimentally the value of CWD as a refuge from predation. CWD was the dominant above-bottom physical structure in shallow water, ranging in size from small branches (50 cm diameter). In response to experimental additions of CWD, densities of common epibenthic cpecies ( Callinectes sapidus, Fundulus heteroclitus, Fundulus majalis, Gobiosoma bosc, Gobiesox strumosus, Palaemonetes pugio , and Rithropanopeus harrisii ) increased significantly compared to control sites without CWD. In laboratory experiments, grass shrimp ( P. pugio ) responded to predatory fish ( F. heteroclitus and Micropogonias undulatus ) by utilizing shelter at CWD more frequently than in absence of fish. Access to CWD increased survivorship of grass shrimp in laboratory and field experiments. These experimental results (1) support the hypothesis, commonly proposed but untested for freshwater habitats, that CWD can provide a refuge from predation for epibenthic fish and invertebrates and (2) extend the recognized functional importance of CWD in freshwater to estuarine and marine Communities. We hypothesize that CWD is an especially important refuge habitat in the many estuarine and freshwater systems for which alternative physical structure (e.g., vegetation or oyster reefs) are absent or in low abundance.
-
coarse woody debris as a refuge from predation in Aquatic Communities an experimental test
Oecologia, 1993Co-Authors: R. A. Everett, G. M. RuizAbstract:This study demonstrates experimentally that coarse woody debris (CWD) can provide refuge from predation in Aquatic habitats. In the Rhode River subestuary of Chesapeake Bay, Maryland, (USA), we (1) measured the abundance of CWD, (2) examined the utilization of CWD by mobile epibenthic fish and crustaceans, and (3) tested experimentally the value of CWD as a refuge from predation. CWD was the dominant above-bottom physical structure in shallow water, ranging in size from small branches ( 50 cm diameter). In response to experimental additions of CWD, densities of common epibenthic cpecies (Callinectes sapidus, Fundulus heteroclitus, Fundulus majalis, Gobiosoma bosc, Gobiesox strumosus, Palaemonetes pugio, and Rithropanopeus harrisii) increased significantly compared to control sites without CWD. In laboratory experiments, grass shrimp (P. pugio) responded to predatory fish (F. heteroclitus and Micropogonias undulatus) by utilizing shelter at CWD more frequently than in absence of fish. Access to CWD increased survivorship of grass shrimp in laboratory and field experiments. These experimental results (1) support the hypothesis, commonly proposed but untested for freshwater habitats, that CWD can provide a refuge from predation for epibenthic fish and invertebrates and (2) extend the recognized functional importance of CWD in freshwater to estuarine and marine Communities. We hypothesize that CWD is an especially important refuge habitat in the many estuarine and freshwater systems for which alternative physical structure (e.g., vegetation or oyster reefs) are absent or in low abundance.
Blake Matthews - One of the best experts on this subject based on the ideXlab platform.
-
rapid divergence of predator functional traits affects prey composition in Aquatic Communities
The American Naturalist, 2019Co-Authors: Dominik Werner Schmid, Matthew D Mcgee, Rebecca J Best, Ole Seehausen, Blake MatthewsAbstract:Identifying traits that underlie variation in individual performance of consumers (i.e., trait utility) can help reveal the ecological causes of population divergence and the subsequent consequences for species interactions and community structure. Here, we document a case of rapid divergence (over the past 100 generations, or ∼150 years) in foraging traits and feeding efficiency between a lake and stream population pair of threespine stickleback. Building on predictions from functional trait models of fish feeding, we analyzed foraging experiments with a Bayesian path analysis and elucidated the traits explaining variation in foraging performance and the species composition of ingested prey. Despite extensive previous research on the divergence of foraging traits among populations and ecotypes of stickleback, our results provide novel experimental evidence of trait utility for jaw protrusion, gill raker length, and gill raker spacing when foraging on a natural zooplankton assemblage. Furthermore, we discuss how these traits might contribute to the differential effects of lake and stream stickleback on their prey Communities, observed in both laboratory and mesocosm conditions. More generally, our results illustrate how the rapid divergence of functional foraging traits of consumers can impact the biomass, species composition, and trophic structure of prey Communities.
Alain Dejean - One of the best experts on this subject based on the ideXlab platform.
-
Environmental drivers of community diversity in a neotropical urban landscape: a multi-scale analysis
Landscape Ecology, 2017Co-Authors: Stanislas Talaga, Frédéric Petitclerc, Jean-françois Carrias, Olivier Dézerald, Céline Leroy, Régis Céréghino, Alain DejeanAbstract:Context Many Aquatic Communities are linked by the aerial dispersal of multiple, interacting species and are thus structured by processes occurring in both the Aquatic and terrestrial compartments of the ecosystem. Objectives To evaluate the environmental factors shaping the Aquatic macroinvertebrate Communities associated with tank bromeliads in an urban landscape. Methods Thirty-two bromeliads were georeferenced to assess the spatial distribution of the Aquatic meta-habitat in one city. The relative influence of the Aquatic and terrestrial habitats on the structure of macroinvertebrate Communities was analyzed at four spatial scales (radius = 10, 30, 50, and 70 m) using redundancy analyses. Results We sorted 18,352 Aquatic macroinvertebrates into 29 taxa. Water volume and the amount of organic matter explained a significant part of the taxa variance, regardless of spatial scale. The remaining variance was explained by the meta-habitat size (i.e., the water volume for all of the bromeliads within a given surface area), the distance to the nearest building at small scales, and the surface area of buildings plus ground cover at larger scales. At small scales, the meta-habitat size influenced the two most frequent mosquito species in opposite ways, suggesting spatial competition and coexistence. Greater vegetation cover favored the presence of a top predator. Conclusions The size of the meta-habitat and urban landscape characteristics influence the structure of Aquatic Communities in tank bromeliads, including mosquito larval abundance. Modifications to this landscape will affect both the terrestrial and Aquatic compartments of the urban ecosystem, offering prospects for mosquito management during urban planning.
Andrew Hull - One of the best experts on this subject based on the ideXlab platform.
-
Temporal dynamics of Aquatic Communities and implications for pond conservation
Biodiversity and Conservation, 2012Co-Authors: Christopher Hassall, James Hollinshead, Andrew HullAbstract:Conservation through the protection of particular habitats is predicated on the assumption that the conservation value of those habitats is stable. We test this assumption for ponds by investigating temporal variation in macroinvertebrate and macrophyte Communities over a 10-year period in northwest England. We surveyed 51 ponds in northern England in 1995/6 and again in 2006, identifying all macrophytes (167 species) and all macroinvertebrates (221 species, excluding Diptera) to species. The alpha-diversity, beta-diversity and conservation value of these ponds were compared between surveys. We find that invertebrate species richness increased from an average of 29.5 species to 39.8 species between surveys. Invertebrate gamma-diversity also increased between the two surveys from 181 species to 201 species. However, this increase in diversity was accompanied by a decrease in beta-diversity. Plant alpha-, beta- and gamma-diversity remained approximately constant between the two periods. However, increased proportions of grass species and a complete loss of charophytes suggests that the Communities are undergoing succession. Conservation value was not correlated between sampling periods in either plants or invertebrates. This was confirmed by comparing ponds that had been disturbed with those that had no history of disturbance to demonstrate that levels of correlation between surveys were approximately equal in each group of ponds. This study has three important conservation implications: (i) a pond with high diversity or high conservation value may not remain that way and so it is unwise to base pond conservation measures upon protecting currently-speciose habitats; (ii) maximising pond gamma-diversity requires a combination of late and early succession ponds, especially for invertebrates; and (iii) invertebrate and plant Communities in ponds may require different management strategies if succession occurs at varying rates in the two groups.
-
Temporal dynamics of Aquatic Communities and implications for pond conservation
Biodiversity and Conservation, 2012Co-Authors: Christopher Hassall, James Hollinshead, Andrew HullAbstract:Conservation through the protection of particular habitats is predicated on the assumption that the conservation value of those habitats is stable. We test this assumption for ponds by investigating temporal variation in macroinvertebrate and macrophyte Communities over a 10-year period in northwest England. We surveyed 51 ponds in northern England in 1995/6 and again in 2006, identifying all macrophytes (167 species) and all macroinvertebrates (221 species, excluding Diptera) to species. The alpha-diversity, beta-diversity and conservation value of these ponds were compared between surveys. We find that invertebrate species richness increased from an average of 29.5 species to 39.8 species between surveys. Invertebrate gamma-diversity also increased between the two surveys from 181 species to 201 species. However, this increase in diversity was accompanied by a decrease in beta-diversity. Plant alpha-, beta- and gamma-diversity remained approximately constant between the two periods. However, increased proportions of grass species and a complete loss of charophytes suggests that the Communities are undergoing succession. Conservation value was not correlated between sampling periods in either plants or invertebrates. This was confirmed by comparing ponds that had been disturbed with those that had no history of disturbance to demonstrate that levels of correlation between surveys were approximately equal in each group of ponds. This study has three important conservation implications: (i) a pond with high diversity or high conservation value may not remain that way and so it is unwise to base pond conservation measures upon protecting currently-speciose habitats; (ii) maximising pond gamma-diversity requires a combination of late and early succession ponds, especially for invertebrates; and (iii) invertebrate and plant Communities in ponds may require different management strategies if succession occurs at varying rates in the two groups.
