Browsing by Author "Rychlik, Leszek"
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Item Diets and coexistence in Neomys and Sorex shrews in Białowieża Forest, eastern Poland(2006) Churchfield, Sara; Rychlik, LeszekPrey selection, food niche overlap and resource partitioning were investigated in semi-aquatic Neomys fodiens and N. anomalus and terrestrial Sorex araneus and S. minutus coexisting in marshland in Białowieża Forest, eastern Poland. Evidence of prey selectivity was found but high levels of overlap, particularly in prey size, reflected the abundance of invertebrates in field samples. Despite similarities in diets between all four species, evidence of niche differentiation was found in terms of foraging mode and prey composition. Neomys took predominantly terrestrial prey but 20% of prey of N. fodiens was aquatic (compared with 11% in N. anomalus) with Asellus being the dominant aquatic prey. Sorex shrews were exclusively terrestrial in foraging mode. All species ate predominantly small prey (<5 mm) and these were most abundant in field samples, but small prey were most important for S. minutus. Pair-wise comparisons suggested that the most important promoter of resource partitioning was body size, indicating different foraging modes. Food niche overlap was least between species most dissimilar in size. The tiny S. minutus was predominately an epigeal forager on small Araneae, Opiliones and Coleoptera; the medium-sized S. araneus fed extensively on Lumbricidae and Coleoptera; and the large, semi-aquatic Neomys fed on different amounts of freshwater prey in addition to terrestrial prey. Our results support the prediction that microhabitat selection among these species indicates differentiation in foraging mode.Item Differences in swimming and diving abilities between two sympatric species of water shrews: Neomys anomalus and Neomys fodiens (Soricidae)(2009) Mendes-Soares, Helena; Rychlik, LeszekSwimming and diving abilities of two syntopic species of water shrews, Neomys anomalus and N. fodiens, were tested in aquaria using video-recordings taken from three views (lateral distant, lateral close and dorsal). The frequency and total duration of diving, as well as the mean duration of diving and floating bouts, were significantly higher in N. fodiens than in N. anomalus. Frequency of paddling during surface swimming was lower in N. fodiens than in N. anomalus. N. fodiens dived mainly for long distances at the bottom of the aquarium and performed a wider range of dive profiles than N. anomalus, which preferred rather short and shallow dives. The two species differed also significantly in their Fineness Ratios (describing how streamlined their bodies are) when diving. When swimming, N. fodiens had a relatively wider body and performed narrower movements with its tail than N. anomalus. These results show quantitatively and qualitatively for the first time that N. fodiens is more proficient at swimming and diving than N. anomalus. The results also help to explain the interspecific differences in efficiency of underwater foraging, and support the idea of segregation of ecological niches of these species based on their different foraging modes (diving vs wading).Item Differentiation of flea communities infesting small mammals across selected habitats of the Baltic coast, central lowlands, and southern mountains of Poland(2014-03-13) Kowalski, Krzysztof; Eichert, Urszula; Bogdziewicz, Michał; Rychlik, LeszekOnly a few studies comparing flea composition on the coast and in the mountains have been conducted. We investigated differences in flea communities infesting small mammals in selected habitats in northern, central and southern Poland. We predicted: (1) a greater number of flea species in the southeastern Poland and a lower number in the north; (2) a greater number of flea species in fertile and wet habitats than in poor and arid habitats; (3) a low similarity of flea species between flea communities in western and eastern Poland. We found negative effect of increasing latitude on flea species richness. We suppose that the mountains providing a variety of environments and the limits of the geographic ranges of several flea subspecies in southeastern Poland, result in a higher number of flea species. There was positive effect of increasing wetness of habitat on flea species richness. We found a high diversity in flea species composition between western and eastern Poland (beta diversity = 11) and between central and eastern Poland (beta diversity = 12). Re-colonization of Poland by small mammals and their ectoparasites from different (western and eastern) refugies can affect on this high diversity of flea species.Item First results on the feeding ecology of the Transcaucasian water shrew Neomys teres (Soricomorpha: Soricidae) from Armenia(2006) Churchfield, Sara; Rychlik, Leszek; Yavrouyan, Eduard; Turlejski, KrisMicroscopic examination of alimentary tracts of fourteen Neomys teres (Miller, 1908) from a mountainous region in northern Armenia produced the first data on the diet of this almost unknown species of conservation concern. Twenty-three different prey types were distinguished in summer-caught shrews, all invertebrates (14 terrestrial and 9 aquatic in origin). The dominant dietary items were Coleoptera and Diptera adults, Araneae, Opiliones and Lumbricidae plus freshwater crustaceans and Trichoptera larvae. Prey ranged from <3 to >16 mm in length but those eaten most frequently were 6-10 mm in length. Although it was captured beside streams and rivers, aquatic prey comprised only 27% of dietary composition. Despite its morphological similarity to N. fodiens, its foraging niche more closely resembles that of upland populations of N. anomalus and its reliance on aquatic habitats remains equivocal.Item Interspecific aggression and behavioural domination among four sympatric species of shrews(2006) Rychlik, Leszek; Zwolak, RafałLevel of interspecific aggressiveness should reflect intensity of interference competition, and large-dominant and small-subordinate species should evolve aggressive and passive agonistic behaviours, respectively, to achieve stable co-existence. We tested these ideas investigating interspecific behavioural dominance in a four-species community of shrews differing in body size (Sorex minutus Linnaeus, 1766; Sorex araneus Linnaeus, 1758; Neomys anomalus Cabrera, 1907; Neomys fodiens (Pennant, 1771)), by placing interspecific pairs in a neutral field. The order of dominance (determined on the basis of duration of offensive and defensive behaviours, total time spent in the shelter, and ‘final shelter resident’ index) corresponded to the order of body size: N. fodiens > N. anomalus > S. araneus > S. minutus. The highest number of conflicts and least pronounced dominance of N. anomalus over S. araneus suggest the strongest interference competition between these species. The different social organization of N. anomalus (tolerant and gregarious versus intolerant and solitary in the other three species) did not decrease its aggressiveness and dominance rank. The larger Neomys species were more aggressive and initiated relatively more offensive behaviours, whereas the smaller Sorex species initiated more defensive behaviours. The presence of food and shelter did not intensify conflicts. Nevertheless, dominating species restricted the access of subordinate species to the shelter.Item Natural infections of small mammals with blood parasites on the borderland of boreal and temperate forest zones(2005) Karbowiak, Grzegorz; Rychlik, Leszek; Nowakowski, Wojciech; Wita, IrenaBlood parasites of small mammals living in Białowieża Forest (eastern Poland) were investigated between 1996 and 2002. The following haemoparasite species were found: Trypanosoma (Herpetosoma) evotomys in bank vole Clethrionomys glareolus and root vole Microtus oeconomus; Babesia microti in root vole; Hepatozoon erhardovae in bank vole and Hepatozoon sp. in root vole. Some non-identified Bartonella species were found in bank vole, root vole, field vole Microtus agrestis, yellow-necked mouse Apodemus flavicollis, common shrew Sorex araneus, Eurasian water shrew Neomys fodiens, and Mediterranean water shrew N. anomalus. The prevalence and diversity of blood parasites were lower in shrews than small rodents. Totally, 52.0% of bank voles, 50.0% of root voles, 32.5% of common shrews, and 41.2% of Eurasian water shrews were infected with any of the blood parasites. Mixed infections were seldom observed in bank vole (17.3% of investigated individuals) and root vole (14.7%). No animals were infected with three or four parasites simultaneously. Infection of Białowieża small mammals with haemoparasites seemed to be similar to those described in other temperate forest regions rather than boreal ones. Infection rates of rodent species seem to be higher in their typical habitats: for bank vole it was the highest in mixed forest, whereas for root vole in sedge swamp. The results suggest that Microtidae play a greater role than Muridae or Soricidae in maintenance of Babesia and Hepatozoon foci in natural environments of central Europe.Item Overlap of temporal niches among four sympatric species of shrews(2005) Rychlik, LeszekHypotheses about the dependence of circadian activity from metabolic rate and the segregation of temporal niches among competing species were verified by the study of activity patterns in a shrew community of two semiaquatic species, Neomys anomalus Cabrera, 1907 and N. fodiens (Pennant, 1771), and two terrestrial species, Sorex araneus Linnaeus, 1758 and S. minutus Linnaeus, 1766, co-existing in wet habitats of Białowieża Forest (E Poland). In ten trapping sessions, performed in early summer between 1991 and 2000, traps were open 24 hours continuously and patrolled at 1:00, 5:00, 10:00, 15:00, and 20:00. All the shrew species were most active between 20:00 and 1:00, and least active around mid-day (10:00-15:00). However, activity of the two Sorex species was lower than that of the two Neomys species in the period 20:00-1:00, but higher in the period 15:00-20:00. Both Neomys species displayed clearly nocturnal, unimodal patterns of activity. In contrast, activity of both Sorex species was relatively evenly distributed over 24 hours and they increased their activity earlier (ie after 15:00) than both Neomys species (after 20:00). These results confirm the idea that small shrew species with higher metabolic rate have more frequent and more equally distributed activity bouts than large species. Overlap of temporal niches was the highest within genera (99.29% between both Neomys species and 98.36% between both Sorex species), the lowest between N. fodiens and S. araneus (88.26%) and S. minutus (89.34%), and intermediate between N. anomalus and both Sorex species (91.78 and 93.34%, respectively). Such high interspecific overlaps suggest a joint-action of other mechanisms that separate ecological niches of these species also in other dimensions (eg food, microhabitat).Item Prey size, prey nutrition, and food handling by shrews of different body sizes(2002) Rychlik, Leszek; Jancewicz, ElżbietaSome predictions relating metabolic constraints of foraging behavior and prey selection were tested by comparison of food handling and utilization in four sympatric shrew species: Sorex minutus (mean body mass=3.0 g), S. araneus (8.0 g), Neomys anomalus (10.0 g), and N. fodiens (14.4 g). Live fly larvae, mealworm larvae and aquatic arthropods were offered to shrews as small prey (body mass <0.1 g). Live earthworms, snails and small fish were large prey (>0.3 g). The larvae were the highly nutritious food (>8 kJ/g) and the other prey were the low nutritious food (<4 kJ/g). The smallest S. minutus utilized (ate+hoarded) <30% of offered food, and the other species utilized >48% of food. The larger the shrew, the more prey it ate per capita. However, highly energetic insect larvae composed 75% of food utilized by S. minutus and only >40% by the other species. Thus, inverse relationships appeared between shrew body mass and mass-specific food mass utilization and between shrew body mass and mass-specific food energy utilization: the largest N. fodiens utilized the least food mass and the least energy quantity per 1 g of its body. Also, the proportion of food hoarded by shrews decreased with an increase in size. With the exception of S. araneus, the size of prey hoarded by the shrews was significantly larger than the size of prey eaten. Tiny S. minutus hoarded and ate smaller prey items than the other shrews, and large N. fodiens hoarded larger prey than the other shrews.Item Sex differences in flea infections among rodent hosts: is there a male bias?(2015) Kowalski, Krzysztof; Bogdziewicz, Michał; Eichert, Urszula; Rychlik, LeszekRecognizing patterns of parasite distribution among wildlife hosts is of major importance due to growing risk of transmission of zoonotic diseases to humans. Thus, sex-dependent parasite distribution in higher vertebrates is extensively studied, and males are often found more parasit- ized than females. Male-biased parasitism may be the result of weaker immunocompetence of male hosts owing to the im- munosuppressive effect of androgens. Moreover, larger hosts (males) may demonstrate higher parasite infestation levels than smaller individuals (females), as they constitute a better nutritional resource for parasites and provide them with a greater variety of niches. In the present work, we investigated sex-dependent patterns of flea distribution among three com- mon rodent species (Apodemus agrarius, Apodemus flavicollis, and Myodes glareolus). We hypothesized that males have a higher flea infestation than females. We confirm male-biased parasitism in A. agrarius and M. glareolus, but not in A. flavicollis. Additionally, flea infestation increased with body mass in A. agrarius, but not in A. flavicollis and M. glareolus. The detected differences in parasite distribution among sexes are probably the result of immunosuppressive effects of androgens and spatial behavior of males.Item Trypanosoma (Megatrypanum) ornata sp. n., a Parasite of the Eurasian Water Shrew Neomys fodiens (Pennant, 1771)(2005) Karbowiak, Grzegorz; Wita, Irena; Rychlik, LeszekInfection with the new trypanosome species Trypanosoma ornata sp. n. was detected in water shrews Neomys fodiens examined for presence of blood parasites in September 2003 and 2004 in Białowieża Forest (eastern Poland). The prevalence of infection was about 36.3%. The trypanosomes occurred as trypomastigote forms only, the epimastigote, dividing forms or other developmental stages were not observed. The morphological features of the species (big body size, small kinetoplast located close to the cell margin, the presence of vermiform posterior end, the surface of the cell markedly striated with longitudinal ‘myonemes”, short free flagellum) support its affiliation to Megatrypanum subgenus. The detail morphometric characterization is given.