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The Aquatic Warbler Acrocephalus paludicola was once a common breeding bird in mesotrophic fen mires all over Central and Western Europe. In the last century large parts of its habitat have been destroyed by wetland drainage and agricultural intensification. Besides protecting the remaining breeding habitats, it is of great importance to preserve suitable migration stopover habitats and wintering grounds to avert the extinction of the species. We determined home-range size and the use of vegetation associations of Aquatic Warblers on the wintering grounds in a flooded plain north of the Djoudj National Park in Senegal. Individual birds (11) were caught in mist nets and equipped with radio transmitters. Locations were assessed by radiotelemetry and a compositional analysis was conducted to determine which vegetation types were preferred within home ranges. Similar to their behaviour on the breeding grounds, the Aquatic Warblers showed no territorial behaviour in their winter quarters. They used home ranges that averaged 4 ha in size, which they shared with conspecifics and other warblers. The home ranges overlapped 54% on average, with a maximum of 90% in an area used by four individuals. The vegetation structure of the wintering habitat is similar to breeding grounds and stopover sites of the species. Preferential vegetation had 80% to 100% cover and consisted of 60 to 90 cm high stands of Oryza longistaminata, Scirpus maritimus or Eleocharis mutata. Most birds stayed more often near the edge of open water, probably for foraging. A constant inundation seems essential, because Aquatic Warblers never occurred in desiccated parts of the study site.
The research concerned the behaviour of a wild boar population in a large (7,500 ha) contiguous forest complex. The results obtained through telemetry include the size of home ranges, daily home ranges, and movement rates of the individuals observed. The separation of female and male home ranges was revealed. The researchers established that the wild boars were most often to be found in Scots pine stands in fresh mixed broadleaved forest habitats.
The resting site choice of 14 pine martens Marten martes (Linnaeus, 1758) (6 males and 8 females) in Białowieża National Park (BNP), north-eastern Poland, was analysed. The radio-collared martens were located 1,790 times in 877 different resting sites. For both males and females, arboreal resting sites (cavity and nest) constituted over 95% of the resting events. Cavities were used more frequently than nests. Resting site use differed significantly between sexes and seasons. Females rested in nests less often than males (especially in spring), but selected cavities more frequently than did males. Females with young chose only cavities, whereas non-breeding females often rested in nests. Weather conditions influenced the choice of resting sites in various months. For males, temperature was a significant factor from October to May, for females from December to March and in June-July. Martens rested in nests when mean ambient temperatures were higher, in cavities or on the ground when tempera­tures were lower. In summer and winter, when average humidity was high males often rested in cavities or places on the ground. When winds were strong or snow cover was deep, martens chose ground sites. In years of high squirrel density, frequency of nest use by marten increased. During severe winters, frequency of use of ground sites increased. Oak, lime, and spruce trees were frequently used by martens (males - 85.7% and female - 70.6% of all resting sites). Males rested in spruce more often than females, while females used oak and lime more often than males. Martens selected lime and oak, and avoided hornbeam trees. Literature on winter resting sites of pine martens in Europe was reviewed. It was shown that in northern Europe martens rested primarily on the ground. In the temperate zone, martens used cavities in trees (eastern Europe) on nests (western Europe).
Although thermal cover receives attention from managers, variations in data regarding its use by ungulates hinders development of effective cover guidelines. We examined patterns of habitat selection and activity of radio-collared cow moose Alces alces Linnaeus, 1758 to determine if these 2 parameters were influenced by ambient thermal environment. Cow moose used sites with relatively denser forest canopies when conditions of heat stress existed in open areas. Use of open areas did not change with ambient temperature; some sites classed as open on forest cover maps, however, had willow canopies capable of providing thermal cover. An increase in the use of open sites from 11.00 to 24.00 hr corresponded to a simultaneous decrease in the likelihood of thermal stress in such areas; predator-avoidance was deemed unlikely to explain observed behaviour. Moose decreased activity and distance traveled between successive locations during hot periods. Summer thermal cover is a selected, manage­able component of moose habitat in southern British Columbia.
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