Habitat quality, not habitat amount, drives mammalian habitat use in the Brazilian Pantanal

Red-knobbed coot, Fulica cristata, was formerly distributed across several countries in the south-west Palaearctic. Remnant populations are now located in Morocco and Spain. In the latter, the red-knobbed coot is considered critically endangered, and its decline is attributed to changes in agricultural practices in the basins of wetlands, which have affected the quality and quantity of food. However, red-knobbed coot is currently more abundant in Morocco. Foraging behaviour reveals information about an animal’s perception of the place that it currently occupies. Thus, we hypothesised that if habitat quality is lower in Spain than in Morocco, this should be expressed in the foraging activity of coots, which should be greater in Spain to compensate for the lower food availability. Our results supported this prediction: red-knobbed coots spent more time foraging in Spain than in Morocco. Furthermore, we compared the foraging behaviour of red-knobbed and common coots, Fulica atra, in southern Spain, where common coot does not face conservation problems, and found that red-knobbed coots spent more time foraging than common coots to meet daily energetic needs. Overall, our results suggested that constraints of food quality and quantity on habitat use were more severe for red-knobbed coots than for common coots, and that this may be a key factor for the conservation of red-knobbed coot in Spain. Managers should try to facilitate longer hydroperiods in wetlands, which would ensure higher quality food during longer periods for coots.

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Habitat Specificity Modulates the Response of Small Mammals to Habitat Fragmentation, Loss, and Quality in a Neotropical Savanna

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.751315 ◽

2021 ◽

Vol 9 ◽

Author(s):

Ingrid de Mattos ◽

Bárbara Zimbres ◽

Jader Marinho-Filho

Keyword(s):

Species Composition ◽

Functional Diversity ◽

Habitat Loss ◽

Habitat Quality ◽

Small Mammals ◽

Small Mammal ◽

Patch Size ◽

Landscape Configuration ◽

Habitat Amount ◽

Habitat Generalists

Landscape conversion of natural environments into agriculture and pasture are driving a marked biodiversity decline in the tropics. Consequences of fragmentation might depend upon habitat amount in the landscape, while the quality of remnants can also affect some species. These factors have been poorly studied in relation to different spatial scales. Furthermore, the impacts of these human-driven alterations may go beyond species loss, possibly causing a loss of ecosystem function and services. In this study, we investigated how changes in landscape configuration (patch size and isolation), habitat loss (considering a landscape gradient of 10, 25, and 40% of remnant forest cover), and habitat quality (forest structure) affect small mammal abundance, richness, taxonomic/functional diversity, and species composition in fragmented landscapes of semideciduous forests in the Brazilian Cerrado. Analyses were performed separately for habitat generalists and forest specialists. We live-trapped small mammals and measured habitat quality descriptors four times in 36 forest patches over the years 2018 and 2019, encompassing both rainy and dry seasons, with a total capture effort of 45,120 trap-nights. Regression analyses indicated that the effect of landscape configuration was not dependent on the proportion of habitat amount in the landscape to determine small mammal assemblages. However, both patch size and habitat loss impacted different aspects of the assemblages in distinct ways. Smaller patches were mainly linked to an overall increase in small mammal abundance, while the abundance of habitat generalists was also negatively affected by habitat amount. Generalist species richness was determined by the proportion of habitat amount in the landscape. Specialist richness was influenced by patch forest quality only, suggesting that species with more demanding habitat requirements might respond to fragmentation and habitat loss at finer scales. Taxonomic or functional diversity were not influenced by landscape structure or habitat quality. However, patch size and habitat amount in the landscape were the major drivers of change in small mammal species composition in semideciduous forests in the Brazilian savanna.

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Erosion of phylogenetic diversity in Neotropical bat assemblages: findings from a whole-ecosystem fragmentation experiment

10.1101/534057 ◽

2019 ◽

Author(s):

Sabhrina G. Aninta ◽

Ricardo Rocha ◽

Adrià López-Baucells ◽

Christoph F. J. Meyer

Keyword(s):

Habitat Quality ◽

Evolutionary History ◽

Phylogenetic Diversity ◽

Secondary Forest ◽

Habitat Modification ◽

Forest Fragments ◽

Habitat Amount ◽

Alpha And Beta Diversity ◽

Continuous Forest ◽

Ecosystem Fragmentation

AbstractThe traditional focus on taxonomic diversity metrics for investigating species responses to habitat loss and fragmentation has limited our understanding on how biodiversity is impacted by habitat modification. This is particularly true for taxonomic groups such as bats which exhibit species-specific responses. Here, we investigate phylogenetic alpha and beta diversity of Neotropical bat assemblages across two environmental gradients, one in habitat quality and one in habitat amount. We surveyed bats in 39 sites located across a whole-ecosystem fragmentation experiment in the Brazilian Amazon, representing a gradient of habitat quality (interior-edge-matrix, hereafter IEM) in both continuous forest and forest fragments of different sizes (1, 10, and 100 ha; forest size gradient). For each habitat category, we quantified alpha and beta phylogenetic diversity, then used linear models and cluster analysis to explore how forest area and IEM gradient affect phylogenetic diversity. We found that the secondary forest matrix harboured significantly lower total evolutionary history compared to the fragment interiors, especially the 1 ha fragments, containing bat assemblages with more closely related species. Forest fragments ≥ 10 ha had levels of phylogenetic richness similar to continuous forest, suggesting that large fragments retain considerable levels of evolutionary history. The edge and matrix adjacent to large fragments tend to have closely related lineages nonetheless, suggesting phylogenetic homogenization in these IEM gradient categories. Thus, despite the high mobility of bats, fragmentation still induces considerable levels of erosion of phylogenetic diversity, suggesting that the various evolutionary history might not be able to persist in present-day human-modified landscapes.

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Are wild populations ideally distributed? Variations in density-dependent habitat use by age class in juvenile Atlantic salmon (Salmo salar)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f08-087 ◽

2008 ◽

Vol 65 (8) ◽

pp. 1667-1680 ◽

Cited By ~ 25

Author(s):

A. Jamie F. Gibson ◽

Heather D. Bowlby ◽

Peter G. Amiro

Keyword(s):

Atlantic Salmon ◽

Habitat Use ◽

Salmo Salar ◽

Habitat Quality ◽

Normal Function ◽

Age Classes ◽

Density Dependent ◽

Atlantic Salmon Salmo Salar ◽

Juvenile Atlantic Salmon ◽

Habitat Gradient

We examined relationships between abundance and habitat use in three age classes of juvenile Atlantic salmon ( Salmo salar ) in the Stewiacke River, Nova Scotia, Canada. Using stream gradient as a proxy for habitat quality, we used a double half normal function, modified to include density dependence, to model the relationship between habitat quality and fish density. We found that density was asymmetrically distributed around a similar optimum gradient for all three age classes regardless of abundance. Habitat use was highly density-dependent for age-0 and age-1 juveniles, but not for age-2+ salmon. As abundance of age-0 and age-1 salmon increased, their relative density decreased in low-gradient habitat and increased in higher-gradient habitat, although their absolute density increased in all stream gradient categories. Variation in habitat use was consistent with ideal free theory for age-1 juveniles in high-gradient habitat, but not in low-gradient habitat. Age-2+ individuals appeared not to modify their distribution among habitats, even though increasing competition changes the relative benefit of low-gradient habitat in terms of resource acquisition. In contrast, age-1 individuals responded to increased competition by modifying their distribution along the habitat gradient, even though this may have slightly reduced an individual’s potential for growth.

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Stopover Habitat use by Spring Migrant Landbirds: The Roles of Habitat Structure, Leaf Development, and Food Availability

The Auk ◽

10.1093/auk/124.3.1063 ◽

2007 ◽

Vol 124 (3) ◽

pp. 1063-1074 ◽

Cited By ~ 3

Author(s):

Paul G. Rodewald ◽

Margaret C. Brittingham

Keyword(s):

Habitat Use ◽

Foraging Behavior ◽

Food Availability ◽

Habitat Quality ◽

Leaf Development ◽

Mature Forest ◽

Forest Interior ◽

Large Trees ◽

Stopover Habitat ◽

Empidonax Minimus

AbstractStopover habitat quality may influence the abundance of migrant landbirds, yet little is known about how spatial and temporal changes in stopover habitat quality influence the use of habitats by migrant landbirds. From late April to late May, 1997–1999, we surveyed migrant landbirds within five habitats (early successional shrub-sapling-stage forest, midsuccessional pole-stage forest, mature forest interior, mature forest-agricultural edge, and mature suburban forest) in central Pennsylvania. To assess relative quality of stopover habitats, we measured species abundance, species richness, and foraging behavior of Yellow-rumped Warblers (Dendroica coronata). We measured vegetation structure and phenology to examine proximate cues of potential importance in habitat selection. Of nine transient (nonbreeding) species analyzed, seven-Least Flycatcher (Empidonax minimus), Nashville Warbler (Vermivora ruficapilla), Northern Parula (Parula americana), Magnolia Warbler (D. magnolia), Black-throated Blue Warbler (D. caerulescens), Yellow-rumped Warbler, and Blackpoll Warbler (D. striata)-were most abundant in mature forests, and especially edge-dominated mature forests (forest-agricultural edge and suburban forest). Habitats used by mature-forest-breeding transients changed between years, but edge-dominated forest types were used most frequently in all three years. Although canopy leaf development at mature forest sites showed little relationship to site use by mature-forest-breeding transients within weekly intervals, year-to-year differences in leaf phenology were consistent with year-to-year changes in habitat use by migrant landbirds. Foraging behavior of Yellow-rumped Warblers suggested higher food availability and quality in forest-agricultural edges, compared with suburban forest and forest interior. Mature-forest-breeding transients were positively associated with sites that had large trees (>38 cm diameter at breast height) and denser understory vegetation (stems 0–2.5 cm in diameter). Extensive use of mature edge-dominated forests by migrating forest birds during spring suggests that these habitats may be important for the conservation of migrant landbirds.Uso de Hábitat durante las Escalas Migratorias por Aves Migratorias Terrestres: el Papel de la Estructura del Hábitat, el Desarrollo de las Hojas y la Disponibilidad de Alimento

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Erosion of phylogenetic diversity in Neotropical bat assemblages: findings from a whole-ecosystem fragmentation experiment

Biodiversity and Conservation ◽

10.1007/s10531-019-01864-y ◽

2019 ◽

Vol 28 (14) ◽

pp. 4047-4063 ◽

Cited By ~ 3

Author(s):

Sabhrina G. Aninta ◽

Ricardo Rocha ◽

Adrià López-Baucells ◽

Christoph F. J. Meyer

Keyword(s):

Habitat Quality ◽

Evolutionary History ◽

Phylogenetic Diversity ◽

Secondary Forest ◽

Habitat Modification ◽

Forest Fragments ◽

Habitat Amount ◽

Alpha And Beta Diversity ◽

Continuous Forest ◽

Ecosystem Fragmentation

Abstract The traditional focus on taxonomic diversity metrics for investigating species responses to habitat loss and fragmentation has limited our understanding of how biodiversity is impacted by habitat modification. This is particularly true for taxonomic groups such as bats which exhibit species-specific responses. Here, we investigate phylogenetic alpha and beta diversity of Neotropical bat assemblages across two environmental gradients, one in habitat quality and one in habitat amount. We surveyed bats in 39 sites located across a whole-ecosystem fragmentation experiment in the Brazilian Amazon, representing a gradient of habitat quality (interior-edge-matrix, hereafter IEM) in both continuous forest and forest fragments of different sizes (1, 10, and 100 ha; forest size gradient). For each habitat category, we quantified alpha and beta phylogenetic diversity, then used linear mixed-effects models and cluster analysis to explore how forest area and IEM gradient affect phylogenetic diversity. We found that the secondary forest matrix harboured significantly lower total evolutionary history compared to the fragment interiors, especially the matrix near the 1 ha fragments, containing bat assemblages with more closely related species. Forest fragments ≥ 10 ha had levels of phylogenetic richness similar to continuous forest, suggesting that large fragments retain considerable levels of evolutionary history. The edge and matrix adjacent to large fragments tend to have closely related lineages nonetheless, suggesting phylogenetic homogenization in these IEM gradient categories. Thus, despite the high mobility of bats, fragmentation still induces considerable levels of erosion of phylogenetic diversity, suggesting that the full amount of evolutionary history might not be able to persist in present-day human-modified landscapes.

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Hierarchical habitat-use by an endangered steppe bird in fragmented landscapes is associated with large connected patches and high food availability

Scientific Reports ◽

10.1038/s41598-019-55467-2 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Julia Gómez-Catasús ◽

Vicente Garza ◽

Manuel B. Morales ◽

Juan Traba

Keyword(s):

Habitat Use ◽

Food Availability ◽

Habitat Quality ◽

Patch Size ◽

Explanatory Power ◽

Space Use ◽

Least Squares Regression ◽

Fragmented Landscapes ◽

Hierarchical Nature ◽

Dupont’S Lark

AbstractMultidimensional approaches must be employed when addressing habitat use patterns. In this study, we aim to elucidate the hierarchical nature of space use by species inhabiting fragmented landscapes, using the threatened Dupont’s lark (Chersophilus duponti). The intensity of space use by Dupont’s lark was estimated using the Kernel Density Function on territory locations in 2015. We measured descriptors of habitat quality at metapopulation (connectivity and patch size), landscape (land-use types and anthropogenic disturbance) and microhabitat-scale (plant structure and composition, herbivore abundance and food availability) at 37 sampling stations. We fitted a Partial Least Squares Regression (PLSR) which yielded two components, accounting for 81% of total variance. Metapopulation-scale factors had the greatest explanatory power (32%), followed by microhabitat (17%) landscape (10%) and spatial predictors (3.6%). Connectivity and patch size were key factors explaining habitat use, and wind farms had a negative effect. At microhabitat-scale, space use was positively associated with Coleoptera, Orthoptera, Araneae and Diptera biomass, but negatively with Formicidae and Blattodea biomass, the cover of Stipa spp, Koeleria vallesiana and moss. This research highlights the hierarchical nature of habitat use in fragmented landscapes. Therefore, conservation measures should ensure connectivity, guarantee a minimum patch size, and improve habitat quality within patches.

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