Modeling freshwater mussel distribution in relation to biotic and abiotic habitat variables at multiple spatial scales

2014 ◽  
Vol 71 (10) ◽  
pp. 1483-1497 ◽  
Author(s):  
Ericka E. Hegeman ◽  
Scott W. Miller ◽  
Karen E. Mock
Keyword(s):  
Large Scale ◽  
Freshwater Mussels ◽  
Spatial Scales ◽  
Freshwater Mussel ◽  
Habitat Associations ◽  
Habitat Characteristics ◽  
Physical Habitat ◽  
Lotic Ecosystem ◽  
Unit Scale ◽  
Channel Unit

The habitat requirements of many native freshwater mussels remain unclear despite their imperiled status and ecological importance. To explore scale-specific habitat associations in the three genera of mussels found in the western United States (Anodonta, Gonidea, and Margaritifera) we used a multiscale random forest modeling approach to assess functional habitat parameters throughout a 55 km segment of the upper Middle Fork John Day River in northeastern Oregon. We characterized mussel occurrence and density with respect to the hierarchical, hydrogeomorphic structure by sampling reaches of varying valley confinement and channel units nested within individual reaches. Each genus exhibited unique longitudinal trends and channel unit-use patterns. In particular, the large-scale longitudinal trends in Margaritifera occurrence were associated with hydrogeomorphic characteristics at the reach and channel unit scale, with Margaritifera densities peaking in narrow valley segments and in riffles and runs. At the scale of the channel unit, all mussel genera responded to variation in physical habitat characteristics, particularly those that indicated more stable parts of the channel. Our results suggest that spatial patterns in freshwater mussels are associated with the hierarchical structuring of the lotic ecosystem and may provide guidance to restoration efforts.

From continua to patches: examining stream community structure over large environmental gradients

2002 ◽  
Vol 59 (8) ◽  
pp. 1404-1417 ◽  
Author(s):  
Kristopher K Wright ◽  
Judith L Li
Keyword(s):  
Conceptual Framework ◽  
Algal Biomass ◽  
Environmental Gradients ◽  
Spatial Scales ◽  
Habitat Characteristics ◽  
Physical Habitat ◽  
Macroinvertebrate Communities ◽  
Order Stream ◽  
Longitudinal Gradients ◽  
Individual Variables

We present an approach that integrates a conceptual framework with multivariate ordination techniques and traditional parametric analyses to examine biotic and abiotic gradients in stream ecosystems. Ordinations were used to examine multivariate patterns along an environmental gradient, with individual variables used to interpret those patterns across spatial scales. The conceptual framework provides a consistent context to compare community distributions and consequently allows for hypothesis testing using ordinations. To illustrate the approach, we examined the physical template, fish and benthic macroinvertebrate communities, and algal biomass and production along a 1st- through 5th-order stream gradient in eastern Oregon. We hypothesized that longitudinal distributions of physical habitat characteristics, fishes, macroinvertebrates, and periphyton would reflect highly variable, discontinuous gradients. Multivariate patterns were determined by rotating nonparametric ordinations to a common set of variables and comparing them to conceptual models of (i) an ideal continuum, (ii) a random distribution, and (iii) discrete patches. Physical habitat and fishes reflected strong longitudinal gradients, macroinvertebrates were the most patchy, and algal biomass and production were highly variable. Distributions of individual variables from site and stream-order perspectives revealed how different factors, potentially influencing stream communities, may be continuous or patchy depending on spatial scale.

scholarly journals Preliminary assessment of habitat characteristics of woodland caribou calving areas in the Claybelt region of Québec and Ontario, Canada

Rangifer ◽  
2003 ◽  
Vol 23 (5) ◽  
pp. 247 ◽  
Author(s):  
Émilie Lantin ◽  
Pierre Drapeau ◽  
Marcel Paré ◽  
Yves Bergeron
Keyword(s):  
Large Scale ◽  
Rangifer Tarandus ◽  
Forest Cover ◽  
Black Spruce ◽  
Spatial Scales ◽  
Habitat Characteristics ◽  
Percent Cover ◽  
Woodland Caribou ◽  
Vegetation Characteristics ◽  
Forest Cover Types

Woodland caribou (Rangifer tarandus caribou) require a diversity of forested habitats over large areas and may thus be particularly affected by the large-scale changes in the composition and age-class distribution of forest landscapes induced by the northern expansion of forest management. In this study we examine habitat characteristics associated to the use of calving areas by woodland caribou females and calves at different spatial scales. Thirty females were captured and collared with Argos satellite transmitters that allowed to locate 14 calving areas. Field surveys were conducted at each of these areas to measure the landscape composition of forest cover types and local vegetation characteristics that are used for both forage conditions and protection cover. At the scale of the calving area, univariate comparisons of the amount of forest cover types between sites with and without calves showed that the presence of calves was associated to mature black spruce forest with a high percent cover of terrestrial lichens. Within calving grounds, univariate comparisons showed that vegetation features like ericaceans and terrestrial lichens, that are important food resources for lactating females, were more abundant in calving areas where females were seen with a calf in mid-July than in areas where females were seen alone. The protection of the vegetation cover against predators was however similar between calving areas with or with¬out a calf. Logistic regression results also indicated that vegetation characteristics associated to forage conditions were positively associated to calf presence on calving grounds. Our results suggest that foraging conditions should be given more attention in analyses on habitat requirements of woodland caribou.

scholarly journals Sources and Expectations for Hierarchical Structure in Bird-habitat Associations

The Condor ◽  
2006 ◽  
Vol 108 (1) ◽  
pp. 5-12 ◽  
Author(s):  
William B. Kristan
Keyword(s):  
Hierarchical Structure ◽  
Environmental Variables ◽  
Spatial Scales ◽  
Ground Level ◽  
Threshold Level ◽  
Habitat Associations ◽  
Habitat Characteristics ◽  
Coarse Grained ◽  
Fine Grained ◽  
Bird Habitat

Abstract Hierarchical structure in bird-habitat associations can arise from hierarchical structure in environmental variables and from the scale-dependent responses of birds to habitat. Hierarchical structure in environmental variables is expected to result from interactions between variables that differ in grain size (spatial resolution) and frequency, and should occur commonly. Birds cannot accurately sample habitat characteristics at all spatial scales simultaneously, and the habitat chosen for a given purpose may differ depending on whether a bird samples from high above the ground (which is best for sampling coarse-grained variables) or from ground level (which is best for sampling fine-grained variables). Additionally, birds may exhibit an absolute response to a habitat variable, if it is unsuitable beyond some threshold level, or a relative response, if all available habitat is suitable but some is preferred. Models that can represent hierarchical structure in habitat, as well as hierarchical, scale-dependent responses by birds, should provide researchers the best chance of understanding avian habitat associations.

Issues Based on Species Life History and Behavior

2021 ◽  
pp. 89-94
Author(s):  
Joseph A. Veech
Keyword(s):  
Life History ◽  
Habitat Use ◽  
Life Histories ◽  
Radio Telemetry ◽  
Spatial Scales ◽  
Habitat Associations ◽  
Habitat Characteristics ◽  
Habitat Analysis ◽  
The Individual ◽  
And Behavior

Species vary tremendously in their life histories and behavior. The particular life history traits and behavior of the focal species must be considered when designing a study to examine habitat associations. For some species, individuals use different areas (of the landscape or territory) for breeding and foraging. As such, the important characteristics for the foraging and breeding habitats may be different. The dramatically different life stages of some organisms (e.g., amphibians and some insects) often correspond to equally dramatic differences in habitat use between juveniles and adults. For some species, habitat use differs among seasons. Species that are highly mobile and have individuals that move around substantially on a daily or weekly basis are particularly challenging for a habitat analysis. For these species, the most efficient and appropriate study design may be one that tracks individuals (through radio-telemetry or GPS) and analyzes the environmental or habitat characteristics at locations where the individual has stopped, rather than trying to survey for the species in pre-established and insufficiently small survey plots. In addition, individual movement and the issues mentioned above may necessitate that environmental variables are measured and analyzed at multiple spatial scales.

Juvenile masu salmon (Oncorhynchus masou) abundance and stream habitat relationships in northern Japan

1997 ◽  
Vol 54 (6) ◽  
pp. 1331-1341 ◽  
Author(s):  
Mikio Inoue ◽  
Shigeru Nakano ◽  
Futoshi Nakamura
Keyword(s):  
Habitat Use ◽  
Riparian Forest ◽  
Spatial Scales ◽  
Masu Salmon ◽  
Stream Habitat ◽  
Oncorhynchus Masou ◽  
Unit Scale ◽  
Salmon Population ◽  
Masu Salmon Oncorhynchus Masou ◽  
Channel Unit

Relationships between abundance of juvenile masu salmon (Oncorhynchus masou) and stream habitat were analyzed on two spatial scales, stream reach and channel unit, in northern Hokkaido, Japan. Reach-scale analyses revealed that high water temperatures limited the salmon population level and that the salmon abundance increased with cover availability. These two limiting factors were strongly associated with the presence of riparian forest, emphasizing its importance for the salmon population. Channel-unit scale analyses showed greater use of pools by the salmon, with greater depth and abundant cover underlying the patterns of habitat use. However, the relative importance of depth and cover varied among the reach types having different cover availability. In reaches that had abundant cover, cover itself was less important in determining patterns of habitat use within the reaches. In contrast, in reaches with poor cover, patterns of habitat use were strongly affected by cover. The results indicated that habitat characteristics at the reach scale affect not only the salmon abundance of the stream reaches, but also the determinants of local abundance patterns of the salmon within the reaches. It was suggested that larger-scale influences in a hierarchy of habitat scales should be considered for better understanding of fish-habitat relationships.

Tributaries, sediment sources, and the longitudinal organisation of macroinvertebrate fauna along river systems

2001 ◽  
Vol 58 (4) ◽  
pp. 824-840 ◽  
Author(s):  
S P Rice ◽  
M T Greenwood ◽  
C B Joyce
Keyword(s):  
Spatial Scales ◽  
River System ◽  
Water Volume ◽  
Physical Habitat ◽  
River Continuum ◽  
Regulated Rivers ◽  
New Model ◽  
Lotic Ecosystem ◽  
Continuum Concept ◽  
Stream Biota

Tributary confluences are sites along a main channel where, because of the introduction of water and (or) sediment, the water volume, bed sediment character, and water quality of the mainstream can change abruptly. These shifts ensure that abiotic gradients seldom vary smoothly or continuously for distances of more than 100–102 km along any river system. The ways in which tributaries and related sediment recruitment points structure longitudinal changes in physical habitat are examined. Variables of importance to stream biota are affected and, in turn, it is suggested that the arrangement of tributaries and related features is an important control on the longitudinal organisation of macroinvertebrate benthos at moderate spatial scales. A new model is presented that stresses the importance of hydrological and sedimentological networks for organising lotic fauna. The link discontinuity concept emphasises the discontinuous nature of lotic ecosystem gradients, addresses the importance of tributaries in unregulated as well as regulated rivers, and extends, to its logical conclusion, the limited recognition of tributary influence in the river continuum concept. A case study from British Columbia, Canada, illustrates the general merit of the new model.

scholarly journals Downstream Changes in Odonate (Insecta: Odonata) Communities along a Suburban to Urban Gradient: Untangling Natural and Anthropogenic Effects

Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 201
Author(s):  
Wade B. Worthen ◽  
R. Kile Fravel ◽  
Connor P. Horne
Keyword(s):  
Large Scale ◽  
Spatial Scales ◽  
Principal Component ◽  
Open Water ◽  
Information Criteria ◽  
Habitat Characteristics ◽  
Small Scale ◽  
Larval Abundance ◽  
Percent Cover ◽  
Surrounding Landscape

The community structure of lotic odonates (Insecta: Odonata) changes downstream, but it is difficult to untangle natural and anthropogenic causes. We surveyed larvae and adults at 15 sites along the Reedy River in Greenville Co., SC, USA, from sites in forested suburban landscapes through the urban core of the city of Greenville. We used principal component analyses and Akaike information criteria models to describe the relationships between larval and adult community descriptors (abundance, richness, and diversity) and habitat characteristics at several spatial scales, including water chemistry, sediment and detritus, aquatic and streamside vegetation, and the percent cover of landforms in the surrounding landscape. At all scales, larval abundance, richness, and diversity correlated with the amount of detritus. At a small scale, adult indices correlated with the amount of sunlight and streamside vegetation. Zygopteran community composition was nested at a large scale; richness and diversity did not correlate with changes in the landscape but increased downstream. Anisopteran composition was also nested, but richness correlated with the percent cover of field, wetland, and open water in the habitat and was unrelated to downstream site position. Landscape transformation affected anisopterans more than zygopterans by opening habitats that facilitate these generalist heliotherms.

Are frog calls modulated by the environment? An analysis with anuran species from Bolivia

2004 ◽  
Vol 82 (6) ◽  
pp. 880-888 ◽  
Author(s):  
J Bosch ◽  
I De la Riva
Keyword(s):  
Large Scale ◽  
Spatial Scales ◽  
Dominant Frequency ◽  
Taxonomic Position ◽  
Habitat Characteristics ◽  
Acoustic Properties ◽  
Small Scale ◽  
Anuran Species ◽  
Opposite Sex ◽  
Habitat Acoustics

Studies have shown that long-range songs of birds and primates are structurally adapted to local habitat acoustics. The evolution of frog calls, however, seems to be less influenced by habitat. Frogs are extremely dependent on energetically costly acoustic signals, which frequently have to be transmitted over large distances to elicit an encounter with the opposite sex. Different acoustic properties of advertisement calls from 95 Bolivian anuran species were analyzed according to their taxonomic position and the habitat characteristics where each species occurred. The majority of call characteristics, such as diversity of notes, number of pulses per note, or dominant frequency, appear strongly related to taxonomic position. Large-scale habitat characteristics (ecoregion and macrohabitat type) were not related to call characteristics, whereas small-scale habitat (microhabitat) complexity appeared to explain some of the variation in dominant frequency modulation. Species that call in closed microhabitats are more likely to use frequency-modulated calls, which may allow for more efficient sound transmission. To further the understanding of frog-call evolution in response to habitat selection, this and other studies have indicated that studies at finer spatial scales are needed, as well as additional studies restricted to the genus or species level.

scholarly journals Ross Sea Benthic Ecosystems: Macro- and Mega-faunal Community Patterns From a Multi-environment Survey

2021 ◽  
Vol 8 ◽  
Author(s):  
Vonda J. Cummings ◽  
David A. Bowden ◽  
Matthew H. Pinkerton ◽  
N. Jane Halliday ◽  
Judi E. Hewitt
Keyword(s):  
Environmental Changes ◽  
Marine Protected Area ◽  
Ross Sea ◽  
Spatial Scales ◽  
Benthic Communities ◽  
Benthic Fauna ◽  
Habitat Characteristics ◽  
Physical Habitat ◽  
Distribution Models ◽  
Suspension Feeders

The Ross Sea, Antarctica, is amongst the least human-impacted marine environments, and the site of the world’s largest Marine Protected Area. We present research on two components of the Ross Sea benthic fauna: mega-epifauna, and macro-infauna, sampled using video and multicore, respectively, on the continental shelf and in previously unsampled habitats on the northern continental slope and abyssal plain. We describe physical habitat characteristics and community composition, in terms of faunal diversity, abundance, and functional traits, and compare similarities within and between habitats. We also examine relationships between faunal distributions and ice cover and productivity, using summaries of satellite-derived data over the decade prior to our sampling. Clear differences in seafloor characteristics and communities were noted between environments. Seafloor substrates were more diverse on the Slope and Abyss, while taxa were generally more diverse on the Shelf. Mega-epifauna were predominantly suspension feeders across the Shelf and Slope, with deposit feeder-grazers found in higher or equal abundances in the Abyss. In contrast, suspension feeders were the least common macro-infaunal feeding type on the Shelf and Slope. Concordance between the mega-epifauna and macro-infauna data suggests that non-destructive video sampling of mega-epifauna can be used to indicate likely composition of macro-infauna, at larger spatial scales, at least. Primary productivity, seabed organic flux, and sea ice concentrations, and their variability over time, were important structuring factors for both community types. This illustrates the importance of better understanding bentho-pelagic coupling and incorporating this in biogeographic and process-distribution models, to enable meaningful predictions of how these ecosystems may be impacted by projected environmental changes. This study has enhanced our understanding of the distributions and functions of seabed habitats and fauna inside and outside the Ross Sea MPA boundaries, expanding the baseline dataset against which the success of the MPA, as well as variability and change in benthic communities can be evaluated longer term.

scholarly journals Inventory and Assemblage Classification of the Freshwater Mussels (Mollusca: Unionidae) of the Strawberry River, Arkansas, USA, with Implications for Conservation Planning

Diversity ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 86
Author(s):  
Alan D. Christian ◽  
Sean T. McCanty ◽  
Sujata Poudel ◽  
Steve W.A. Chordas ◽  
John L. Harris
Keyword(s):  
Indicator Species ◽  
Conservation Planning ◽  
Freshwater Mussels ◽  
Spatial Scales ◽  
Freshwater Mussel ◽  
Central Plateau ◽  
Ozark Highlands ◽  
Species Analysis

Spatial hierarchical approaches to classify freshwater systems can add to our understanding of biogeographical patterns and can be used for biodiversity conservation planning. The Strawberry River is located primarily in the Ozark Highlands Central Plateau of north central Arkansas, USA, with a small downstream portion in the Mississippi Alluvial Plain and has been designated an Extraordinary Resource Water, an Ecologically Sensitive Water Body, and a Natural Scenic Waterway. The goals of this study were to document Strawberry River, Arkansas freshwater mussels to aid in conservation planning. Our first objective was to inventory freshwater mussel species in the Strawberry River. Our second objective was to use this stream-wide dataset to classify the freshwater mussel assemblages. We used unpublished survey data of 59 sites distributed from the headwaters to the mouth to inventory species occurrence and abundance, classified mussel assemblages using non-metric multi-dimensional scaling (NMS), and conducted indicator species analysis on resulting assemblages. We observed 39 taxa across the 59 survey sites including two S1, five S2, 16 S3, 11 S4, four S5, and one state non-ranked conservation rank species. Furthermore, our assemblage NMS revealed two distinct freshwater mussel assemblages roughly organized by an upstream (Sites 1–31) to downstream (Sites 32–59) gradient. There were five upstream indicator species and 13 downstream indicator species. This study provides a case study on using existing datasets with NMS and indicator species analyses to classify mussel assemblages and adds to our understanding of freshwater mussel fauna classification at smaller spatial scales. Both NMS and indicator species outcomes can aid in conservation planning for freshwater mussels.

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