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Horvathova T.,Comenius University | Horvathova T.,University of Oxford | Horvathova T.,Jagiellonian University | Cooney C.R.,University of Oxford | And 9 more authors.
Ecology and Evolution

Understanding the factors that drive geographic variation in life history is an important challenge in evolutionary ecology. Here, we analyze what predicts geographic variation in life-history traits of the common lizard, Zootoca vivipara, which has the globally largest distribution range of all terrestrial reptile species. Variation in body size was predicted by differences in the length of activity season, while we found no effects of environmental temperature per se. Females experiencing relatively short activity season mature at a larger size and remain larger on average than females in populations with relatively long activity seasons. Interpopulation variation in fecundity was largely explained by mean body size of females and reproductive mode, with viviparous populations having larger clutch size than oviparous populations. Finally, body size-fecundity relationship differs between viviparous and oviparous populations, with relatively lower reproductive investment for a given body size in oviparous populations. While the phylogenetic signal was weak overall, the patterns of variation showed spatial effects, perhaps reflecting genetic divergence or geographic variation in additional biotic and abiotic factors. Our findings emphasize that time constraints imposed by the environment rather than ambient temperature play a major role in shaping life histories in the common lizard. This might be attributed to the fact that lizards can attain their preferred body temperature via behavioral thermoregulation across different thermal environments. Length of activity season, defining the maximum time available for lizards to maintain optimal performance, is thus the main environmental factor constraining growth rate and annual rates of mortality. Our results suggest that this factor may partly explain variation in the extent to which different taxa follow ecogeographic rules. © 2013 The Authors. Source

Jelic D.,Croatian Institute for Biodiversity | Ajtic R.,Institute for Nature Conservation of Serbia | Sterijovski B.,Macedonian Ecological Society | Crnobrnja-Isailovic J.,University of Nis | And 3 more authors.
Herpetological Conservation and Biology

Vipers display high specific and sub-specific diversity in the Balkans, but available atlases and red data books provide no precise data about legal status and conservation threats. the three viper species in the Balkans share several conservation problems: lack of systematic study and public interest, "historical and political burdens," lack of knowledge, superstitions and fear among people, increasing urbanization, habitat destruction, illegal collection, as well as lack of adequate (or no) legislation at the country level. here we present an overview of legal status of vipers across five countries (Croatia, Serbia, Bosnia and herzegovina, montenegro, and the former Yugoslav republic of macedonia) and present precise information about particular conservation problems. moreover, we propose conservation priorities and measures for each viper species in each country based on already standardized analyses. We calculated an overall index of relative environmental sensitivity. vipera ursinii was indicated as a species in serious threat of decline (mean score value of 1.9) and v. berus as species possibly vulnerable to decline (score 1.2). vipera ammodytes was indicated as species with low risk of decline (0.7). Based on these scores and previously published distribution data, we made an analysis of important viper areas to indicate areas of special concern. © 2013. Dušan Jelić. All Rights Reserved. Source

Jelic D.,Croatian Institute for Biodiversity | Jelic D.,Institute for Research | Spelic I.,Croatian Institute for Biodiversity | Zutinic P.,University of Zagreb
Acta Zoologica Academiae Scientiarum Hungaricae

108 years after Trgovčić (1908) authors made a revised list of fish species found in rivers and streams of the Lika region. Throughout the 8 years of investigation a total of 31 species of freshwater fish were recorded, of which only eight are indigenous for this area, for two species the origin is not known, and the remaining 21 species are introduced by anthropogenic activity over the last 100 years. This represents the over-domination of introduced species by the astonishing 300%. All of this increase in numbers causes significant increase in biomass and changes the naturally oligotrophic ecosystem, which might lead to rapid eutrophication and increase of water temperature. Furthermore, induced changes in the system make the habitat more suitable for introduced cyprinid fish, which again causes the increase of biomass production. Endemic fish species are retreating into upper parts of small tributaries and underground cave systems. The present research indicates species Delminichthys jadovensis, D. krbavensis, Telestes fontinalis and T. croaticus as real stygophiles, which makes them unique on the European continent. Source

Turic N.,Josip Juraj Strossmayer University of Osijek | Temunovic M.,University of Zagreb | Temunovic M.,Croatian Institute for Biodiversity | Radovic A.,Czech University of Life Sciences | And 3 more authors.
Freshwater Biology

Lowland riverine floodplains are among the most dynamic and heterogeneous of ecosystems, but many have been extensively modified. Their provision of important habitats provides a key motivation for restoring natural flow regimes (in terms of magnitude, frequency, duration, timing and rate of change of hydrological conditions). Despite general recognition that aquatic insects respond to changes in water availability, there is little agreement about the influence of flow regime components on community structure in floodplains. We analysed a 6-year (2005 and 2007-2011) data set of aquatic insects (Heteroptera and Coleoptera) in a large Danubian floodplain characterised by pronounced hydrological variability. We hypothesised that abundance and assemblage structure would depend on flow regime components. In particular, we predicted that high-flow events in the mainstream and concurrent high-magnitude floods of prolonged duration would have a positive effect on diversity and abundance and that insect assemblages would differ between phases of hydrological connectivity. In addition, we assessed whether the survival of two threatened aquatic insects, Graphoderus bilineatus and Berosus geminus, depends on hydrological connectivity. Abundance and species richness of Heteroptera and Coleoptera increased during years with frequent extremely high flood pulses and prolonged flooding. Multivariate ordination showed subtle relationships between hydrological conditions, hydrological connectivity and insect assemblages with number of days in flood providing the best fit. Spring floods had a more pronounced effect on the assemblages than autumn floods. The time lag between flood occurrence and its apparent effect on aquatic insects was 17-31 days, reflecting insect life cycles. The abundance of G. bilineatus (Coleoptera: Dytiscidae) was affected by mean water level during the month preceding sampling, whereas the abundance of B. geminus (Coleoptera: Hydrophilidae) was related to the occurrence of prolonged high-magnitude floods. The current water regime of the Danube River favours generalist species with high dispersal capacities and broad niches and food resources. Changes in flow management practices could remove the positive influence of floods on aquatic insect communities and lead to losses of threatened species that depend on these river-floodplain habitats. Our results contribute to the understanding necessary for appropriate evaluation and prioritisation of international floodplain conservation efforts. © 2015 John Wiley & Sons Ltd. Source

Landeka N.,Public Health Institute of the Istrian | Podnar M.,Croatian Natural History Museum | Jelic D.,Croatian Institute for Biodiversity
Periodicum Biologorum

Background and Purpose: In the early 20th century, two native North American poeciliid species Gambusia holbrooki and Gambusia affinis were introduced to Europe as a mosquito control agent. The first introduction to Istria from Italy in 1924 was followed by several independent introductions and massive translocations. Presently, the distribution of these two species in Croatia and Bosnia and Herzegovina (Bosnia and Herzegovina) is still largely unknown and they are often confused. The purpose of this study was to determine the taxonomic status of individual Gambusia populations and to shed more light on the distribution and phylogeographic patterns of these invasive species in Croatia and Bosnia and Herzegovina. Materials and Methods: All new and literature data were plotted together to obtain the overall distribution of Gambusia sp. in Croatia and Bosnia and Herzegovina. The samples collected across this range were analysed meristically and by means of mitochondrial cytochrome b (cytb) gene sequence analysis to ascertain the true taxonomic status of the populations. For phylogeographic analysis, the cytb sequences from this study were combined with previously published data. Results and Conclusions: The methods only confirmed the presence of G. holbrooki. G. holbrooki is continuously distributed across the entire Mediterranean biogeographical region in Croatia and Bosnia and Herzegovina. Two different mitochondrial cytb haplotypes were found: the widely spread Hol1 haplotype and haplotype Hol5 that in Europe was previously found only in France and Greece. This suggests that G. holbrooki populations in the region originated from different stocks. © 2015 Croatian Society of Natural Sciences. All rights reserved. Source

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