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A modification of the Sherman trap, intended for live-trapping of shrews (Soricidae), is presented. This trap requires only daily checks, in contrast to the two- to four-hourly checks required by other traps. A population study using the new trap design yielded 711 captures over 7 520 trap-days, with 1% mortality.
Periods of no activity between 02.00 and 10.00 and lasting for up to 7 h 40 min are reported for two captive Crocidura flavescens (I. Geoffroy, 1827). During one of these periods, the weight specific energy requirement of the shrew dropped to 25.1% of the usual, indicating a period of spontaneous torpor. Nest-box temperatures also drop during the periods of prolonged inactivity suggesting a lowered body temperature. Data for a younger animal suggest shorter periods of torpor. The timing of the torpor spans the coldest period of the day when the animal would expend most energy maintaining a constant body temperature.
The successful raising one young of one female Crocidura f. flavescens by another is reported. Attempts at using C. h. hirta and Myosorex varius as foster parents, and as well as at hand rearing of C. f. flavescens were unsuccessful. An attempt is made to explain the significance of this occurrence.
Pelage color variants have been documented in some small mammals, but there is not any reported about coat color variation in shrews. Here, pelage color variants of the two sibling species (Sorex cylindricauda and Sorex bedfordiae) were uncovered in different sampling sites. Our data may initiate new interest to pelage color variants in small mammals. Furthermore, the classification of two striped shrews has been controversial for several decades. We conducted a detailed examination of the morphometric characters for the two sibling shrews. Significant differences between the two species morphologically confirmed the two-species classification status.
The diet of Cryptotis meridensis Thomas, 1898 was studied by analysing stomach contents of 55 shrews collected by pitfall trapping in the cloud forest of Monte Zerpa, Mérida, Venezuela. The aims of the study were to describe the diet of this unknown tropical species and test the prediction that this species should be more of a subterranean feeder according to its morphological adaptations. The diet was composed of 35 different prey taita distributed in six invertebrate classes (Gastropoda, Annelida, Arachnida, Crustacea, Myriapoda and Insecta). The most important components of the diet were hypogeal invertebrates: Oligochaeta, Gastropoda, Theraposidae, Isopoda, Scolopendridae, Phasmatidae, Blatiidae, Lepidoptera larvae and pupae, Diptera larvae, adult Carabidae, Staphilinidae, Elateridae larvae, Passalidae and Scarabaeidae larvae. Their contribution was 69.44% of the overall diet composition. Oligochaeta were the most frequent prey. Ephigeal invertebrates (Lycosidae, Acrididae, Gryllidae, adult Scarabaeidae and Lycosidae) accounted for only 27,24%. The preferences for soil invertebrates found in this study confirmed our prediction that C. meridensis uses mostly a subterranean foraging mode in accord with its morphological adaptations similar to other shrews in temperate habitats.
The rich and well-preserved bone material of six shrew species extracted from the filling of a karstic cavity near the town of Varshets (Prebalkan region, North Bulgaria) is described. The samples of Beremendia fissidens, Asoriculus gibberodon, Sorex cf. minutus and S. runtonensis represent relatively large forms of these species, while Petenyia hungarica does not grately differ from the other European populations. The Varshets record of S. runtonensis extends the stratigraphical range of the species into the Late Pliocene. The skull fragments determined as Mafia aff. csarnotensis show that this species has four upper antemolars; this number has not so far been known and the studied material contributes to the characteristic of this poorly known genus. The position of the Varshets assemblage within the context of the temporal and spatial variation of the species composition and structure of 23 Pliocene and Early Pleistocene shrew associations from Europe is assessed by correspondence analysis. The results point to a mosaic environment under a relatively warm and dry climate. On the basis of this analysis the ecological interpretation of Asoriculus gibberodon as a strict dweller in wet forests is questioned. The comparisons indicate that it tends to occur in shrew associations related to mosaic landscapes dominated by shrubby and open habitat patches.
The common shrew Sorex araneus Linnaeus, 1758 and pygmy shrew S. minutus Linnaeus, 1766 were live-trapped for 10 months in a spruce plantation. Mean home range sizes were 1058 (SD = 381) m2 for the common shrew and 2146 (SD = 147) m2 for the pgymy shrew. The density estimates of S. araneus varied from 4 ind/ha in winter to 26 ind/ha in summer, and these of S. minutus were 2 ind/ha and 7 ind/ha, respectively. Peak densities for both species occurred during August. It appears that maintaining a viable population of these two shrew species in this spruce plantation requires no special precaution.
The successful rearing of young Sorex araneus Linnaeus, 1758 by conspecific foster mothers is reported. Nursing shrews showed no aversion towards the presence of strange young in the nest, irrespective of age and size differences, as well as non­-familiar odours of these young. Two adults put in the same container with their young showed no signs of aggression, even after successive removal of the young. The observed phenomena suggest that either olfactory cues are not effective at this stage of development or that maternal instinct inhibits the contradictory information of these cues.
I investigated geographic variation in the Japanese white-toothed shrew Crocidura dsinezumi (Temminck, 1842) (Insectivora, Soricidae) from the Japanese Archipelago and the northern part of the Ryukyu Archipelago. Univariate and multivariate analyses were conducted based on 11 cranial measurements from 14 sampling localities. Overall size variation seemed to follow clinal changes correlated with latitude and longitude of localities, such that northeastern populations were smaller than southwestern ones. The Hokkaido population and the Kuchinoerabujima population were larger than expected based on estimated values, likely due to changes reflecting environmental factors. In contrast, the Tanegashima population was smaller than its estimated value. The northern Ryukyu populations were divergent from the Kyushu population and from each other. Based on patterns of geographic variation, I suggest that all previously described subspecies of C. dsinezumi are junior synonyms of C. dsinezumi; and that the Kuchinoerabujima population and the Nakanoshima population likely represent un- described subspecies.
The hypothesis, that shrews avoid intra- and interspecific aggression through a reduction of their loco-motor activity, was tested. In 55 neutral arena tests (each of 30-min-duration), 10 subadult individuals of Sorex minutus, 14 of S. araneus, 9 (including 1 adult male) of Neomys anomalus, and 13 of N. fodiens were used. Loco-motor activity and sum of conflicts (attacks, chases, escapes and threats) in 1st-5th minutes of interactions (phase I) and 10th-15th minutes (phase II) were compared. In all the species, both in intra- and interspecific interactions, a reduction of mobility between phases I and II was observed (in 6 out of 16 comparisons the difference was statistically significant, and in the 7th comparison it was fairly significant). The highest reduction of activity was observed in the smallest S. minutus, and the lowest reduction (no difference was significant) in the largest, dominating N. fodiens.
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