Habitat Selection by 2 Closely Related Skinks, Egernia-Modesta Storr and Egernia-Whitii Lacepede (Lacertilia, Scincidae)

1986 ◽  
Vol 13 (2) ◽  
pp. 295 ◽  
Author(s):  
DA Milton ◽  
JM Hughes
Keyword(s):  
Habitat Selection ◽  
Human Disturbance ◽  
Habitat Preferences ◽  
Canopy Cover ◽  
Niche Separation ◽  
Grass Cover ◽  
Allopatric Populations ◽  
Narrow Zone ◽  
Current Distributions ◽  
Microhabitat Preferences

'The habitat and microhabitat preferences, and times of activity, of the skinks Egernia modesta and E. whitii were examined in southern Queensland where they coexist in a narrow zone. The above parameters were compared between locally sympatric and allopatric populations, in an attempt to determine whether there was evidence of niche separation in sympatry. E. modesta preferred open habitats with little canopy cover and high grass cover, adjacent to rocky retreats. E. whitii preferred rocky areas with well developed canopy and shrub layers. Both species were active throughout the day, although E. modesta was active later than E. whitii. No evidence was found of competition restricting habitat preferences where the two species coexisted. It is suggested that human disturbance has had some influence on current distributions of these species.

Riparian habitat disturbed by reservoir management does not function as an ecological trap for the Yellow Warbler (Setophaga petechia)

2012 ◽  
Vol 90 (3) ◽  
pp. 320-328 ◽  
Author(s):  
S.P. Quinlan ◽  
D.J. Green
Keyword(s):  
Habitat Selection ◽  
Habitat Preferences ◽  
Canopy Cover ◽  
Ecological Trap ◽  
Riparian Habitat ◽  
Yellow Warbler ◽  
Nest Sites ◽  
Selection Decisions ◽  
Yellow Warblers ◽  
Setophaga Petechia

Ecological traps arise when anthropogenic change creates habitat that appears suitable but when selected reduces the fitness of an individual. We evaluated whether riparian habitat within the drawdown zone of the Arrow Lakes Reservoir, British Columbia, creates an ecological trap for Yellow Warblers ( Setophaga petechia (L., 1766)) by investigating habitat preferences and the fitness consequences of habitat selection decisions. Preferences were inferred by examining how habitat variables influenced settlement order, and comparing habitat at nest sites and random locations. Males preferred to settle in territories with more riparian shrub and tree cover, higher shrub diversity, and less high canopy cover. Females built nests in taller shrubs surrounded by a greater density of shrub stems. Habitat preferences were positively associated with fitness: nest sites in taller shrubs surrounded by higher shrub-stem densities were more likely to avoid predation and fledge young, whereas territories with more riparian cover, higher shrub diversity, and less high canopy cover had higher annual productivity. We therefore found no evidence that riparian habitat affected by reservoir operations functions as an ecological trap. Current habitat selection decisions may be associated with fitness because Yellow Warblers are adapted to breeding in a heterogeneous environment subject to periodic flooding.

scholarly journals Nesting habitat selection and challenges of conservation of the vulnerable Lesser Adjutant Leptoptilos javanicus (Horsfield, 1821) in the Chitwan National Park, Nepal

2021 ◽  
Vol 29 (1) ◽  
pp. 33-46
Author(s):  
Bishnu Prasad Bhattarai ◽  
Jagan Nath Adhikari ◽  
Manukala Rijal
Keyword(s):  
Habitat Selection ◽  
Human Disturbance ◽  
National Park ◽  
Canopy Cover ◽  
Tree Height ◽  
Nesting Habitat ◽  
Human Settlements ◽  
Shorea Robusta ◽  
Chitwan National Park ◽  
Nesting Place

Abstract The nesting ecology and conservation threats of the Lesser Adjutant (Leptoptilos javanicus) were studied in the Chitwan National Park, Nepal. We located nine nesting colonies during the nesting season. The number of nests was highly positively correlated with tree height, diameter at breast height and canopy cover. The uppermost canopy of the trees was the most preferred nesting place. Storks preferred to nest in compact colonies on large, widely branched trees with thin foliage cover, such as Bombax ceiba, and also nearby the foraging grounds such as wetlands and grasslands. Storks mostly preferred to nest in Bombax ceiba, but if this tree was not available, they nested in other trees, such as Shorea robusta, Ficus racemosa and Terminalia alata. During the breeding season, 180 adults, 76 nests and 88 chicks were recorded, where the highest number of chicks was recorded near the Sauraha area of the Chitwan National Park. Most of the colonies were far from human settlements, which suggest that human disturbance could be the major determinant of nesting habitat selection in this area. The wetlands nearby human settlements are either overexploited in terms of mass collection of the storks` prey species by people or disturbed highly due to presence of a large number of people. These empirical findings suggest that conservation of Lesser Adjutant mainly rely on the protection of mature Bombax ceiba trees and the reduction of human disturbance and of the collection of stork prey animals from foraging areas.

Den habitat selection of the chinese bamboo rat (Rhizomys sinensis) in Northern Guangxi China

2017 ◽  
Author(s):  
YUAN Bao-dong ◽  
PAN Yang ◽  
YAN Yong-feng
Keyword(s):  
Habitat Selection ◽  
Human Disturbance ◽  
Goodness Of Fit ◽  
Habitat Preferences ◽  
Slope Position ◽  
Suitable Habitat ◽  
Goodness Of Fit Test ◽  
Habitat Features ◽  
Bamboo Rat ◽  
Selection Of

A habitats comprises a range of environmental features that provide adequate resources for wildlife to survive. Consequently, the criteria of habitat selection by animals, combines a wider spectrum of both environmental and other factors, with major prerequisites being food resources, availability of shelter and suitable conditions for reproduction. The den habitat selection of the Chinese bamboo rat (Rhizomys sinensis) was studied in Yuanbaoshan Nature Reserve, Guangxi China. The Vanderloeg and Scavia selectivity index (Ei) indicates that the Chinese bamboo rat shows a preference for all habitat features except for slope, slope position and distance to water (P>0.05). Chi-square goodness of fit test showed that canopy density, shelter from wind, distance between shrubs, shrub density, elevation, southern aspect, human disturbance and food abundance, were the preferred features (P less than 0.05). With regards to human disturbance, the Chinese bamboo rat preferred places >1000 m away from human habitation. An eastern and southern sloping direction, a 20°^~40° slope and an elevation range of >1800m were more frequently used. The Chinese bamboo rat prefers habitats lying above 1000m in elevation with high shrub density (with shrub separation under 0.1m). Principle component analysis indicates that concealment factors, geographical factors, interference factors, food factors, and water factors affect the den habitat character of the Chinese bamboo rat. Our results support the notion that the habitat preferences of the Chinese bamboo rat are a tradeoff between suitable habitat features and avoidance of potential human interactions.

Distribution and habitat preference of protected reindeer lichen species (Cladonia arbuscula, C. mitis and C. rangiferina) in the Balaton Uplands (Hungary)

2021 ◽  
Vol 53 (3) ◽  
pp. 271-282
Author(s):  
Mónika Sinigla ◽  
Erzsébet Szurdoki ◽  
László Lőkös ◽  
Dénes Bartha ◽  
István Galambos ◽  
...  
Keyword(s):  
Vascular Plants ◽  
Management Practices ◽  
Soil Depth ◽  
Habitat Preferences ◽  
Habitat Type ◽  
Canopy Cover ◽  
Lichen Species ◽  
Oak Forests ◽  
Natural Habitats ◽  
Cladonia Rangiferina

AbstractThe maintenance of protected lichen species and their biodiversity in general depends on good management practices based on their distribution and habitat preferences. To date, 10 of the 17 protected lichen species of Hungary have been recorded in the Bakony Mts including the Balaton Uplands region. Habitat preferences of three protected Cladonia species (C. arbuscula, C. mitis and C. rangiferina) growing on underlying rocks of red sandstone, basalt, Pannonian sandstone and gravel were investigated by detailed sampling. We recorded aspect, underlying rock type, soil depth, pH and CaCO3 content, habitat type (as defined by the General National Habitat Classification System Á-NÉR), all species of lichen, bryophyte and vascular plants as well as percentage cover of exposed rock, total bryophytes, lichens, vascular plants and canopy, degree of disturbance and animal impacts. Sporadic populations of these species mostly exist at the top of hills and mountains in open acidofrequent oak forests, but they may occur in other habitats, such as closed acidofrequent oak forests, slope steppes on stony soils, siliceous open rocky grasslands, open sand steppes, wet and mesic pioneer scrub and dry Calluna heaths. Cladonia rangiferina was found to grow beneath higher canopy cover than either C. arbuscula or C. mitis in the Balaton Uplands. Furthermore, there were significant differences in canopy cover between occupied and unoccupied quadrats in the case of all three species. Cladonia rangiferina is a good indicator species of natural habitats in Hungary due to its restricted distribution and low ecological tolerance. These results may lead to the adoption of effective conservation methods (e.g. game exclusion, artificial dispersal) in the future.

Habitat selection of sympatric Siberian Grouse and Hazel Grouse in natural and exploited forests of the lower Amur region

Ornis Fennica ◽  
2022 ◽  
Vol 98 (4) ◽  
pp. 142-161
Author(s):  
Tobias Ludwig ◽  
Ralf Siano ◽  
Alexander V. Andreev
Keyword(s):  
Habitat Selection ◽  
Russian Far East ◽  
Far East ◽  
Canopy Cover ◽  
Late Summer ◽  
Breeding Habitat ◽  
Empirical Modelling ◽  
Hazel Grouse ◽  
Pioneer Trees ◽  
Selection Of

The Siberian Grouse (Falcipennis falcipennis), which is endemic to the “dark-needle” taiga of the Russian Far East, is one of the least studied grouse species in the world. We examined post-breeding habitat selection of Siberian Grouse and contrasted it with that of the better examined Hazel Grouse (Tetrastes bonasia) in two areas near Komsomolsk na Amure, Russia. To infer species-specific preferences, we used field sampling, logistic regression, and AIC model selection, and compared late summer habitats of Siberian Grouse and Hazel Grouse in a mountain- and hilly area in the dark needle taiga. Our study is the first to explain Siberian Grouse habitat relationships with an empirical modelling approach. Results indicate proportions of coniferous/ pioneer trees forest and rejuvenation to be the most important covariates separating Siberian and Hazel Grouse observation sites in forests from both areas. Siberian Grouse tended to select sites with low proportions of pioneer trees and rejuvenation but availability of dwarf shrubs. Bunchberry (Cornus canadensis) appeared to be of high importance for the presence of Siberian Grouse in both regions. Hazel Grouse were common in places dominated by pioneer trees with high canopy cover, and high proportions of grass/herb cover. Hazel Grouse also occurred more often in forest sites with dense vertical layering and rejuvenation. Modern forestry, which results in increasing amounts of forests at younger successional stages, is likely to favour the Hazel Grouse at the expense of the Siberian Grouse.

scholarly journals Habitat Selection in a Changing Environment: The Relationship Between Habitat Alteration and Spotted Owl Territory Occupancy and Breeding Dispersal

The Condor ◽  
2007 ◽  
Vol 109 (3) ◽  
pp. 566-576 ◽  
Author(s):  
Mark E. Seamans ◽  
R.J. Gutiérrez
Keyword(s):  
Habitat Selection ◽  
Sierra Nevada ◽  
Coniferous Forest ◽  
Canopy Cover ◽  
Habitat Alteration ◽  
Breeding Dispersal ◽  
Conifer Forest ◽  
Avian Behavior ◽  
Spotted Owl ◽  
The Relationship

Abstract Abstract. Understanding the effect of habitat alteration on avian behavior is important for understanding a species' ecology and ensuring its conservation. Therefore, we examined the relationship between Spotted Owl habitat selection and variation in habitat in the Sierra Nevada. We estimated habitat selection by modeling the probability of territory colonization (γ), territory extinction (ε), and breeding dispersal in relation to the amount of mature conifer forest within and among territories. Alteration of ≥20 ha of mature conifer forest (coniferous forest with >70% canopy cover dominated by medium [30.4–60.9 cm dbh] and large [>60.9 cm dbh] trees) within individual territories (n  =  66) was negatively related to territory colonization and positively related to breeding dispersal probability. Although territory extinction was negatively related to the amount of mature conifer forest, it was not clear whether this relationship was due to variation of mature conifer forest within or among territories. Although modeling results for territory colonization and extinction generally supported the hypothesis that individuals are “ideal” when selecting a habitat in the sense that they settle in the highest-quality site available, we did not find a clear benefit in terms of habitat quality for Spotted Owls that exhibited breeding dispersal.

A Systems Approach for the Management of Russian Knapweed (Centaurea repens)

1998 ◽  
Vol 12 (2) ◽  
pp. 363-366 ◽  
Author(s):  
Rick M. Bottoms ◽  
Tom D. Whitson
Keyword(s):  
Systems Approach ◽  
Cultural Practices ◽  
Canopy Cover ◽  
Economic Feasibility ◽  
Grass Species ◽  
Grass Cover ◽  
Russian Knapweed ◽  
Centaurea Repens ◽  
Significant Difference ◽  
Russian Wildrye

Studies were initiated in Wyoming to determine the potential of grass competition as an alternative to repetitive herbicide treatment or other cultural practices for control of Russian knapweed. An experiment was established to evaluate the effects of five grass species, including Russian wildrye cv. ‘Bozoisky.’ Picloram, applied to Russian knapweed during the first frost, reduced Russian knapweed from an average of 80.1% live canopy cover which equates to 0% control. Untreated, unseeded checks resulted in 83.9 and 81.1% control in tilled and nontilled treated plots, respectively. Grass cover increased in untreated seeded plots from an average of 11.3 and 8.2% in tilled and nontilled plots, respectively, to 65% in tilled and 66% in nontilled plots treated with clopyralid plus 2,4-D. Grass cover also increased 69.7% in tilled and 66% in nontilled plots treated with picloram. There was no significant difference between grass varieties when compared to percent Russian knapweed cover. Reductions to zero live canopy cover of Russian knapweed were obtained with a single application of picloram. Economic feasibility thresholds were obtained from four out of five varieties, including a significant difference provided by nontilled Russian wildrye treated with picloram.

Moose selection of canopy cover types related to operative temperature, forage, and snow depth

1991 ◽  
Vol 69 (12) ◽  
pp. 3071-3077 ◽  
Author(s):  
Francis E. Schwab ◽  
Michael D. Pitt
Keyword(s):  
Habitat Selection ◽  
Snow Depth ◽  
Canopy Cover ◽  
Late Winter ◽  
Early Winter ◽  
Thermal Limit ◽  
Operative Temperature ◽  
Metabolic Heat ◽  
High Forage ◽  
Selection Of

Simple linear and muliple regressions were used to determine the contribution of operative temperature (Te), forage, and snow depth to moose (Alces alces) selection of canopy cover types. The number of degree-hours for which Te exceeded the thermal limit at which panting is required to dissipate metabolic heat contributed significantly to selection during summer (1 June – 15 September) and late winter (16 January – 15 April). Forage explained canopy cover selection in early winter (16 November – 15 January) and contributed significantly to the best equation describing habitat selection during late winter. Snow depth contributed to habitat selection in early winter but was not related to habitat selection during late winter. During summer, moose generally selected against sites where Te exceeded 30 °C, the thermal limit requiring panting to dissipate metabolic heat. During late winter, moose also generally avoided canopy covers where Te commonly exceeded 8 °C, the temperature at which panting is required to dissipate heat. During early winter, moose apparently suffered minimal heat stress, as Te remained below 0 °C; consequently, moose selected canopy cover types that provided comparatively high forage availability.

Conservation of a rare arboreal mammal: habitat preferences of the Lumholtz's tree-kangaroo, Dendrolagus lumholtzi

2011 ◽  
Vol 33 (1) ◽  
pp. 5 ◽  
Author(s):  
Sigrid R. Heise-Pavlov ◽  
Sara L. Jackrel ◽  
Spenser Meeks
Keyword(s):  
Habitat Selection ◽  
Function Analysis ◽  
Habitat Preferences ◽  
Structural Features ◽  
Main Trunk ◽  
Faecal Pellets ◽  
Eastern Australia ◽  
North Eastern ◽  
Dendrolagus Lumholtzi ◽  
Selection Of

Success of conservation efforts of large and cryptic mammals is often limited due to a lack of knowledge of their habitat preferences. This study investigates factors that affect the habitat selection of the rare Lumholtz’s tree-kangaroo, Dendrolagus lumholtzi, using signs of its activity. The presence and absence of scratch marks on tree trunks and faecal pellets within a 100-cm radius around them were surveyed on 23 ha within a 65-ha large fragment of rainforest on the Atherton Tablelands, north-eastern Australia in order to classify trees as ‘actively used’ or ‘inactive’. Structural features of the 315 surveyed tree trunks were also recorded. Using discriminant function analysis, ‘actively used’ trees were found to have no epiphytes on the main trunk, less obstruction by neighbouring trees, shrubs or lianas within a 0.5-m radius of the trunk (particularly in the eastern direction), and a smaller diameter at breast height than ‘inactive’ trees. Smaller tree trunks and less obstruction may facilitate a more rapid movement into the canopy as well as provide potential escape routes from predators. More specific knowledge on factors that affect habitat selection of the Lumholtz’ tree-kangaroo will help in a reclassification of the threatened status of this species and assist in more effective conservation efforts.

The role of forest canopy cover in habitat selection: insights from the Iberian lynx

2019 ◽  
Vol 65 (2) ◽  
Author(s):  
A. Gastón ◽  
S. Blázquez-Cabrera ◽  
C Ciudad ◽  
M. C. Mateo-Sánchez ◽  
M. A. Simón ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Forest Canopy ◽  
Canopy Cover ◽  
Iberian Lynx
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