scholarly journals Habitatselektion von zwei Waldameisenarten (Formica rufa und F. polyctena)

2019 ◽  
Vol 170 (1) ◽  
pp. 32-39
Author(s):  
Muriel Perron ◽  
Isabelle Glanzmann ◽  
Anne Freitag
Keyword(s):  
Habitat Preferences ◽  
Canopy Cover ◽  
Forest Edge ◽  
Forest Area ◽  
Canopy Height ◽  
Habitat Model ◽  
Habitat Characteristics ◽  
Nest Density ◽  
Formica Rufa ◽  
Ant Mounds

Habitat selection of two wood ant species (Formica rufa and F. polyctena) Wood ants play an important role in the forest ecosystem, but knowledge about their spatial distribution is often outdated or scarce in Switzerland. Species-specific habitat requirements remain poorly understood, especially for the two sympatric species Formica rufa and F. polyctena, preventing the development of efficient conservation measures. Following the survey of wood ant mounds in the cantons of Basel-Landschaft and Basel-Stadt of 2015/2016, we developed a predictive hierarchical habitat model to investigate the relationships between habitat characteristics (slope, canopy cover, canopy height, vertical structure, distance to forest edge, distance to forest roads, proportion of conifers, and proportion of forest area) and the nest density of F. rufa and F. polyctena. By doing so, we adjusted for imperfect detectability of our census method. Most of the habitat factors have been derived from remote-sensing data (LiDAR, false-color images). We found that the two species differ in their smallscale habitat preferences, especially regarding canopy cover, slope and distance to forest edge. Compared to F. polyctena, F. rufa has less marked habitat preferences and is relatively indifferent to canopy height, proportion of forest area and distance to forest edge. Our results are inconsistent with the claim from other studies that F. rufa occurs more frequently at forest edges than F. polyctena. Furthermore, our study emphasizes the need to take into account the detection probability for a large-scale survey of wood ant mounds.

scholarly journals Red wood ants in Bulgaria: distribution and density related to habitat characteristics

2021 ◽  
Vol 85 ◽  
pp. 135-159
Author(s):  
Vera Antonova ◽  
Martin P. Marinov
Keyword(s):  
Canopy Cover ◽  
Field Studies ◽  
Abundant Species ◽  
Habitat Characteristics ◽  
Nest Density ◽  
Ecological Groups ◽  
Red Wood Ants ◽  
Wood Ants ◽  
Current Monitoring ◽  
A Current

The only National Inventory of red wood ants in Bulgaria was carried out about 50 years ago (1970–1973). Formica rufa Linnaeus, 1761, F. pratensis Retzius, 1783, F. lugubris Zetterstedt, 1838 and F. polyctena (as F. polyctena x rufa hybrid) were found in a current monitoring programme. This study presents data on their current distribution and nest density, and provides more details about the habitat requirements for conservation purposes. Field studies were carried out by the transect method along the main mountainous areas in Bulgaria. We found 256 nests of red wood ants along 172 transects. The most abundant species was F. lugubris, followed by F. rufa and F. pratensis. Among the environmental variables, the elevation, exposure, ecological groups of plants, stone cover, grass cover, canopy cover and forest age appeared as significantly related to the presence and nest density of red wood ants.

Temporal Changes in Habitat Selection and Nest Spacing in a Colony of Ross' and Lesser Snow Geese

The Auk ◽  
1983 ◽  
Vol 100 (2) ◽  
pp. 335-343 ◽  
Author(s):  
M. Robert McLandress
Keyword(s):  
Nearest Neighbor ◽  
Average Distance ◽  
Habitat Preferences ◽  
Nearest Neighbors ◽  
Nest Density ◽  
Snow Goose ◽  
Snow Geese ◽  
Lesser Snow Geese ◽  
Average Size ◽  
Island Habitats

Abstract I studied the nesting colony of Ross' Geese (Chen rossii) and Lesser Snow Geese (C. caerulescens caerulescens) at Karrak Lake in the central Arctic of Canada in the summer of 1976. Related studies indicated that this colony had grown from 18,000 birds in 1966-1968 to 54,500 birds in 1976. In 1976, geese nested on islands that were used in the late 1960's and on an island and mainland sites that were previously unoccupied. Average nest density in 1976 was three-fold greater than in the late 1960's. Consequently, the average distance to nearest neighbors of Ross' Geese in 1976 was half the average distance determined 10 yr earlier. The mean clutch size of Ross' Geese was greater in island habitats where nest densities were high than in less populated island or mainland habitats. The average size of Snow Goose clutches did not differ significantly among island habitats but was larger at island than at mainland sites. Large clutches were most likely attributable to older and/or earlier nesting females. Habitat preferences apparently differed between species. Small clutches presumably indicated that young geese nested in areas where nest densities were low. The establishment of mainland nesting at Karrak Lake probably began with young Snow Geese using peripheral areas of the colony. Young Ross' Geese nested in sparsely populated habitats on islands to a greater extent than did Snow Geese. Ross' Geese also nested on the mainland but in lower densities than Ross' Geese nesting in similar island habitats. Successful nests with the larger clutches had closer conspecific neighbors than did successful nests with smaller clutches. The species composition of nearest neighbors changed significantly with distance from Snow Goose nests but not Ross' Goose nests. Nesting success was not affected by the species of nearest neighbor, however. Because they have complementary antipredator adaptations, Ross' and Snow geese may benefit by nesting together.

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.

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 Resource selection by Javan Slow Loris Nycticebus javanicus E. Geoffroy, 1812 (Mammalia: Primates: Lorisidae) in a lowland fragmented forest in Central Java, Indonesia

2019 ◽  
Vol 11 (6) ◽  
pp. 13667-13679 ◽  
Author(s):  
Mahfut Sodik ◽  
Satyawan Pudyatmoko ◽  
Pujo Semedi Hargo Yuwono ◽  
Muhammad Ali Imron
Keyword(s):  
Resource Selection ◽  
Small Sample Size ◽  
Canopy Cover ◽  
Small Sample ◽  
Habitat Characteristics ◽  
Ratio Test ◽  
Natural Habitats ◽  
Slow Loris ◽  
Central Java ◽  
Habitat Variables

Habitat loss and forest fragmentation have negative impacts on Javan Slow Loris Nycticebus javanicus, a Critically Endangered nocturnal primate endemic to Java.  Reports confirmed that less than 9% of forest area remains on Java Island.  One of the remaining natural habitats of the Javan Slow Loris is the fragment of Kemuning Forest in Temanggung Regency, Central Java.  The purpose of this study was to determine resource selection and habitat variables that determine the presence of Javan Slow Loris.  Habitat variables measured were basal area, tree connectivity, crown coverage on tree stage, slope, elevation, and distance to river.  Data analysis performed was logistic regression, likelihood ratio test, and Akaike’s Information Criterion with a backward elimination procedure.  We also used direct observation and interviews with locals to collect data on environment and anthropogenic features of this forest.  The results showed that the Javan Slow Loris uses resources selectively on a microhabitat scale.  The habitat factors that influence the probability of resource selection by the species are canopy cover and slope.  Habitat characteristics preferred by the Javan Slow Loris in Kemuning Forest are secondary lowland tropical rainforest with dense canopy cover located on a steep slope with low level of habitat disturbances.  Although this study uses a small sample size, the expectation is that the results can be used as preliminary information for the habitat and population management of Javan Slow Loris in Kemuning Forest to guide conservation efforts and design management strategies.

scholarly journals The habitat characteristics of Sumatran Elephant (Elephas maximus sumatranus) in the forest of Serbajadi sub-district Aceh Province

2021 ◽  
Vol 922 (1) ◽  
pp. 012055
Author(s):  
Abdullah ◽  
Supriadi ◽  
D Syafrianti ◽  
Khairil ◽  
A M Daud ◽  
...  
Keyword(s):  
Secondary Forest ◽  
Vegetation Type ◽  
Canopy Cover ◽  
Habitat Characteristics ◽  
Elephas Maximus ◽  
Primary Forest ◽  
Tabular Form ◽  
Aceh Province ◽  
Feeding Activities ◽  
Forest Vegetation Type

Abstract The purpose of this study was to determine the habitat characteristics of the Sumatran Elephant in the Serbajadi District Forest. Data collection by looking at the use of habitat which is characterized by the distribution of faeces found in various habitat units in the home range of the Sumatran Elephant. The method used is observation with a track with a size of 3,600 m which is divided into 20 observation plots with a distance between plots of 100 m. The data obtained in the field were analyzed descriptively and presented in tabular form. The results of this study indicate that the Habitat Characteristics of the Sumatran Elephant in the Serbajadi District Forest chose habitat units with very dense canopy cover (>75%), moderate feed availability (26-50%), rare mineral source trees availability (< 3 trees/plot). availability of sparse scrubbing trees (<3 trees/plot), close to primary forest (0-500 m), low land elevation (0- 400 masl), gentle slope (0-20°), close to water sources (0-250m). Secondary forest/vegetation type and frequency of habitat use based on the findings of faeces that the Sumatran elephant most frequently visited was secondary forest than primary forest because the secondary forest was for feeding activities while the primary forest was used for resting and reproduction.

Zoogeomorphosite: A concept for, and example of, linking geoheritage and biodiversity heritage

2021 ◽  
Author(s):  
François Bétard
Keyword(s):  
Mixed Forest ◽  
Slope Aspect ◽  
Major Influence ◽  
Termite Mounds ◽  
Morphometric Measurements ◽  
Small Surface ◽  
Formica Rufa ◽  
Wide Range ◽  
First Results ◽  
Ant Mounds

&lt;p&gt;Zoogeomorphosites can be defined as geomorphological sites of special interest for animal biodiversity and conservation. They appear as ideal places for linking geoheritage and biodiversity heritage because of the reciprocal effects and interactions between landforms and animals. On one hand, geomorphodiversity exerts an influence on animal biodiversity at alpha, beta and gamma levels, and many landforms constitute valuable habitats for a wide range of animal species. On the other hand, animals can have direct and indirect geomorphic effects by creating specific landforms (e.g., mounds) and by influencing geomorphic processes (e.g, runoff), respectively.&lt;/p&gt;&lt;p&gt;The aim of this presentation is (1) to illustrate a worldwide range of sites fitting the conceptual definition of a zoogeomorphosite, with a proposed typology, and (2) to present an example of zoogeomorphological survey conducted on a site in Northwest France (Bois-des-Jarries, Vend&amp;#233;e), where geoheritage meets with biodiversity heritage. The selected study site is a granitic geomorphosite composed of two hills with small tors and boulders outcropping at 230-260 m a.s.l., and franging a large fluvial paleo-valley of Ypresian age. The land cover is a mosaic of mixed forests and dry heathlands recognized for their high ecological interest, with many valuable species of vascular plants, birds and invertebrates. A major zoogeomorphic interest of the site is that it hosts an important population of mound-building red wood ants (&lt;em&gt;Formica rufa&lt;/em&gt;), a regionally rare and vulnerable species responsible for an impressive collection of biogenic microlandforms (ant mounds) on a small surface (62 ha). A zoogeomorphogical survey carried out in summer 2020 on these ant mounds involved a two-stage methodology: (1) linear surveys along forest paths, in order to calculate mound densities and to proceed with a general inventory of ant mounds; (2) morphometric measurements of mounds using strip transects in 13 representative habitat types, in order to calculate mound volumes and to evaluate their evolution on a 5-years period.&lt;/p&gt;&lt;p&gt;119 mounds of &lt;em&gt;Formica rufa&lt;/em&gt; have been inventoried in summer 2020 along the forest paths, indicating a density of 2-4 mounds ha&lt;sup&gt;&amp;#8211;1&lt;/sup&gt;. First results of the morphometric measurements indicate that the highest biovolumes are found in pine or mixed forest habitats, and that the geomorphology of the granitic hills (slope, aspect, height above drainage, etc.) is of major influence on their distribution and shape. In turn, ant mounds create environmental heterogeneity, or patch-scale geodiversity, highly favourable to biodiversity, notably because they offer microhabitats for various myrmecophilous insects. Finally, ant mounds can be viewed as a remarkable example of biogeomorphological heritage, hybrid and evolutionary in nature, but highly sensitive to environmental and human-induced changes (e.g., forest clear cuts, tourism pressure). Because ant mounds are an integral component of natural heritage and a key provider of ecosystem services, their inventory and protection as zoogeomorphosites &amp;#8211; just like that of termite mounds &amp;#8211; are of prime relevance in the wider scope of integrating geodiversity and biodiversity in nature conservation policies and strategies.&lt;/p&gt;

scholarly journals Accuracy Assessment of GEDI Terrain Elevation and Canopy Height Estimates in European Temperate Forests: Influence of Environmental and Acquisition Parameters

2020 ◽  
Vol 12 (23) ◽  
pp. 3948
Author(s):  
Markus Adam ◽  
Mikhail Urbazaev ◽  
Clémence Dubois ◽  
Christiane Schmullius
Keyword(s):  
Laser Scanning ◽  
Temperate Forests ◽  
Accuracy Assessment ◽  
Canopy Cover ◽  
Global Scale ◽  
Canopy Height ◽  
Ecosystem Dynamics ◽  
Vegetation Height ◽  
Height Estimates ◽  
Terrain Elevation

Lidar remote sensing has proven to be a powerful tool for estimating ground elevation, canopy height, and additional vegetation parameters, which in turn are valuable information for the investigation of ecosystems. Spaceborne lidar systems, like the Global Ecosystem Dynamics Investigation (GEDI), can deliver these height estimates on a near global scale. This paper analyzes the accuracy of the first version of GEDI ground elevation and canopy height estimates in two study areas with temperate forests in the Free State of Thuringia, central Germany. Digital terrain and canopy height models derived from airborne laser scanning data are used as reference heights. The influence of various environmental and acquisition parameters (e.g., canopy cover, terrain slope, beam type) on GEDI height metrics is assessed. The results show a consistently high accuracy of GEDI ground elevation estimates under most conditions, except for areas with steep slopes. GEDI canopy height estimates are less accurate and show a bigger influence of some of the included parameters, specifically slope, vegetation height, and beam sensitivity. A number of relatively high outliers (around 9–13% of the measurements) is present in both ground elevation and canopy height estimates, reducing the estimation precision. Still, it can be concluded that GEDI height metrics show promising results and have potential to be used as a basis for further investigations.

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.

scholarly journals Exploring copepod distribution patterns at three nested spatial scales in a spring system: habitat partitioning and potential for hydrological bioindication

2015 ◽  
Author(s):  
Fabio Stoch ◽  
Barbara Fiasca ◽  
Tiziana Di Lorenzo ◽  
Silvano Porfirio ◽  
Marco Petitta ◽  
...  
Keyword(s):  
Spatial Scales ◽  
Habitat Preferences ◽  
Distribution Patterns ◽  
Habitat Characteristics ◽  
Relative Role ◽  
Sediment Texture ◽  
Vertical Scale ◽  
Geomorphic Features ◽  
Spring System ◽  
Isotope Analyses

<p>In groundwater-fed springs, habitat characteristics are primarily determined by a complex combination of geomorphic features and physico-chemical parameters, while species assemblages are even more intricate. Springs host species either inhabiting the spring mouth, or colonizing spring habitats from the surface or from the aquifers which feed the springs. Groundwater species living in springs have been claimed as good candidates for identifying dual aquifer flowpaths or changes in groundwater pathways before reaching the spring outlets. However, the reliability of spring species as hydrological biotracers has not been widely investigated so far. Our study was aimed at analysing a large karstic spring system at three nested spatial scales in order: i) to assess, at whole spring system scale, the presence of a groundwater divide separating two aquifers feeding two spring units within a single spring system, by combining isotope analyses, physico-chemistry, and copepod distribution patterns; ii) to test, at vertical spring system scale, the effectiveness of copepods in discriminating surface and subsurface habitat patches within the complex mosaic spring environment; iii) to explore, at local spring unit level, the relative role of hydrochemistry and sediment texture as describers of copepod distribution among microhabitats. The results obtained demonstrated the presence of a hierarchical spatial structure, interestingly reflected in significant differences in assemblage compositions. Copepod assemblages differed between the two contiguous spring units, which were clearly characterized by their hydrochemistry and by significant differences in the groundwater flowpaths and recharge areas, as derived by the isotope analyses. The biological results suggested that stygobiotic species seem to be related to the origin of groundwater, suggesting their potential role as hydrological biotracers. At vertical scale, assemblage composition in surface and subsurface habitats was significantly different, both between spring units and among microhabitats, supporting strong habitat preferences of copepod species. At the smaller local scale, the response to habitat patchiness of subsurface copepod assemblages resulted in distribution patterns primarily defined by sediment texture, while the sensitivity to differences in hydrochemistry was negligible.</p>

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