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This is the first study on spatial behaviour of brown hares Lepus europaeus Pallas, 1778 based on radio-telemetry in a natural system, which we contrast with data from agricultural systems. Radio tracking took place in a Dutch salt marsh over a 10-month period, with intensive tracking sessions during April/May and December/January. Six hares could be followed in both periods and in total 1224 fixes were collected. Average home range size was calculated as 28.7 ± 8.5 ha when using Adaptive Kernell method (Mimimum Convex Polygon: 27.3 ± 9.0 ha) on 90% of all fixes. Such values are in the lower end of the range of those obtained for agricultural systems. Home range size did not differ between sexes, day and night, or across seasons. However, the size of the core range (50% of fixes) was twice as large in May compared to the winter period, and thus inversely related to food availability. Unlike in agricultural systems, use of space by hares did not change over the course of the season. This probably reflects the patchy nature of the natural habitat which provides food and shelter throughout the year in a confined area.
The effects of pH, electrical conductivity (EC), soluble cations (Na⁺, K⁺, Ca²⁺, Mg²⁺), and soluble anions (HCO₃⁻, Cl⁻, SO₄²⁻) on vegetation zonation in a salt-marsh community (Black Sea coast) were investigated on two localities at Black Sea Coast differing as to the altitude, community composition and zonation. Three zones (25–80 m wide) – lower, middle and upper were distinguished in each locality along 150 m transect and according to the vegetation types which were analysed with Braun-Blanquet method. The dominant species were following: Juncus acutus L., Salicornia prostrata Pall., Spergularia marina (L.) Gris, Hordeum geniculatum All., Plantago coronopus L. subsp. coronopus, Carex capitellata Boiss. and Bal, Artemisia santonicum L. and Juncus littoralis C. A. Mey. Soil samples were taken down to 50 cm. The results of soil analysis were evaluated by using Canonical Correspondence Analysis (CCA) from winter 1999 to autumn 2000. HCO₃⁻ concentration and inundation depth (2.22–21.44 cm) are the environmental variables that correlate the best with axis 1, whereas K⁺ concentration and inundation depth (2.22–21.44 cm) correlate the best with axis 2 during the study period. During winter 1999, HCO₃⁻ concentration showed the highest correlation with the canonical axis 1 and associated zone was H. geniculatum. In spring, summer and autumn 2000, inundation depth (3.44–19.11 cm) was the most prominent factor correlated with the first and second axes, respectively, with associated zone of C. capitellata. EC, Na⁺ and Cl⁻ concentrations were decreased during autumn in all vegetation zones except for C. capitellata and Artemisia santonicum zones in which Na⁺ and Cl⁻ concentrations and EC, respectively were increased during autumn. The C. capitellata (Cyperaceae) zone was located on the positive site of axis 1 during autumn 2000 and followed the gradient of inundation depth. S. prostrata, S. marina, H. geniculatum and P. coronopus subsp. coronopus seems to be adapted to the most saline soils, whereas C.capitellata indicates the wettest soils in the studied salt marsh. The Juncus littoralis zone followed the gradient of maximum salinity during autumn of the year 2000, but the zone was not related to the measured increase in soil salinity during winter, summer and spring. In both localities EC, Na⁺ and Cl⁻ concentrations were tended to decrease at upper zones. Inundation regime, K⁺ concentration, and HCO₃⁻ concentration are key factors affecting vegetation zonation in studied salt marshes.
A new monotypie genus of flatid planthoppers (Hemiptera: Fulgoromorpha: Flatidae) is described from Socotra island (Yemen): Haloflata gen. nov. for H. arthrocnemi sp. nov. (type species). Habitus, male and female external and internal genital structures of the new species are illustrated and compared with similar taxa. The new species was found in association with Arthrocnemum macrostachyum (Amaranthaceae) in coastal saltmarshes in western Socotra.
Notocotylus fosteri sp. nov. (Trematoda, Notocotylidae) is described from the caecum of the rice rat, Oryzomys palustris, from a salt marsh on Waccasassa Bay, Florida, U.S.A. The new species differs from previously described Notocotylus species principally in the extreme prebifurcal position of the genital pore, which overlies the posterior margin of the oral sucker, but also by the number of ventral papillae (10-13/row), and the length of the metraterm relative to the cirrus sac (89%). This is only the second species of this genus found in North American mammals.
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