Fine‐scale ecological and anthropogenic variables predict the habitat use and detectability of sloth bears in the Churia habitat of east Nepal

Fine-scale variation in habitat structure and composition is likely to influence habitat use by avian species with limited flight capabilities. I investigated proportional use of available habitat and microhabitat by the southern emu-wren (Stipiturus malachurus), a threatened, flight-limited passerine, at three sites in Victoria, in relation to vegetation structure and composition. Emu-wrens appeared to discriminate between habitats with regard to structural rather than floristic characteristics. Habitats with dense vertical foliage of shrubs, grasses and sedges/rushes between ground level and 100 cm, and dense horizontal cover of medium to tall shrubs, were used most frequently. However, when availability of habitat was taken into account, habitat use was negatively correlated with the vertical density of low shrub foliage and species richness. Within habitats, emu-wrens more frequently used plant species that had a dense canopy cover (26 ± 2% of total cover, crown diameter 93 ± 5 cm), high foliage density between 50 and 100 cm, and average heights of ~1 m. Plant species in which the birds nested comprised ~14% of total canopy cover and were densest between ground level and 50 cm. Canopy cover, vegetation height and vertical foliage density were consistently important variables correlated with emu-wren habitat use at multiple fine-scales. This study provides valuable information for conservation management of the species; in particular, the restoration of degraded habitats.

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Fine-scale movements and habitat use of juvenile southern flounder Paralichthys lethostigma in an estuarine seascape

Journal of Fish Biology ◽

10.1111/jfb.12074 ◽

2013 ◽

Vol 82 (5) ◽

pp. 1469-1483 ◽

Cited By ~ 37

Author(s):

N. B. Furey ◽

M. A. Dance ◽

J. R. Rooker

Keyword(s):

Habitat Use ◽

Fine Scale ◽

Paralichthys Lethostigma ◽

Southern Flounder

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Aquatic habitat use in a semi-aquatic mammal: the Eurasian beaver

Animal Biotelemetry ◽

10.1186/s40317-021-00259-7 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Rasmus Mohr Mortensen ◽

Stefanie Reinhardt ◽

Marina Eraker Hjønnevåg ◽

Rory Paul Wilson ◽

Frank Rosell

Keyword(s):

Habitat Use ◽

Building Materials ◽

Aquatic Vegetation ◽

Food Resource ◽

Aquatic Habitat ◽

Fine Scale ◽

Aquatic Habitats ◽

Aquatic Mammal ◽

Clay Sediment ◽

Selection For

Abstract Background Semi-aquatic mammals exploit resources both on land and in water and may require both to meet their habitat requirements including food- and building resources, refuges, and for social interactions with conspecifics. Within this, the specific availability of both terrestrial and aquatic resources is expected to impact individual fitness. Beavers are highly dependent on water for movement and protection from predators. They are central place foragers and mostly forage on woody vegetation near water although aquatic vegetation may also be an important food resource. However, little is known about their use of aquatic habitats. We aimed to address this knowledge gap by dead-reckoning fine-scale movement tracks and classifying fine-scale diving events, which we then related to the spatial distribution of aquatic vegetation and habitat components within the territory. Results Overall, there was a statistically clear decrease in probability that diving would occur at dawn and with increasing distance from territory borders. In addition, the distance from the lodge at which animals dived decreased through the night and during the spring/early summer. There was strong selection for diving habitats located closer to the riverbank, with stronger selection for these areas being observed in individuals with larger home ranges. We saw a higher selection for diving above clay sediment, and within 150 m from the lodge, presumably because mud and clay sediment tended to be located closer to the lodge than sand and rock sediment. Furthermore, we found a clear selection for diving in the presence of quillwort (Isoetes spp.), shoreweed (Littorella uniflora), and stonewort (Nitella spp.). Selection for these focal species was stronger among subordinate individuals. Individuals with lower body condition dived closer to the beaver lodge, and dives located further from the lodge were associated with high densities of aquatic vegetation. Conclusion We provide new knowledge on the aquatic habitat use in a semi-aquatic mammal and show how energetic constraints may shape how beavers spatially use the aquatic environment, whereby short and shallow dives appear most beneficial. We show how aquatic habitats may have great importance for both foraging, building materials and safety, and discuss to how they may affect the fitness of individuals.

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Fine-scale movement and habitat use of whitespotted eagle rays Aetobatus narinari in the Indian River Lagoon, Florida, USA

Endangered Species Research ◽

10.3354/esr01047 ◽

2020 ◽

Vol 42 ◽

pp. 109-124 ◽

Cited By ~ 2

Author(s):

BC DeGroot ◽

G Roskar ◽

L Brewster ◽

MJ Ajemian

Keyword(s):

Habitat Use ◽

Brownian Bridge ◽

Indian River Lagoon ◽

Movement Behavior ◽

Anthropogenic Activity ◽

Fine Scale ◽

Boat Traffic ◽

Indian River ◽

Anthropogenic Threats ◽

Potential Interactions

Despite being crucial to the conservation of batoids (skates and rays), assessments of fine-scale movements and habitat use of these taxa are lacking in the scientific literature. Here we used active acoustic telemetry to characterize habitat use and movement behavior of the state-protected whitespotted eagle ray Aetobatus narinari in the Indian River Lagoon, Florida, USA. Seven mature individuals (6 males and 1 female) were individually tracked for a total of 119.6 h. Brownian bridge movement models of ray distribution showed the importance of habitats with high anthropogenic activity (i.e. boat traffic) such as inlets and channels, as well as clam aquaculture lease sites close to shore. This was supported by the significantly lower rates of movement in these habitats relative to other regions (offshore, open lagoon). Rate of movement significantly increased with temperature, suggesting that rays are more active during warmer periods. No tidal patterns in ray habitat use or distribution were evident. On average, rays used the deeper portions of the lagoon during the day and shallower portions during the night. While more extensive tracking is required to elucidate long-term movement patterns, this study is the first to characterize fine-scale habitat use by the whitespotted eagle ray in Florida while also identifying areas of potential interactions between this species and multiple anthropogenic threats.

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