Jaroslav Červený

Increasing Incidence of Geomyces destructans Fungus in Bats from the Czech Republic and Slovakia

Background White-nose syndrome is a disease of hibernating insectivorous bats associated with the fungus Geomyces destructans. It first appeared in North America in 2006, where over a million bats died since then. In Europe, G. destructans was first identified in France in 2009. Its distribution, infection dynamics, and effects on hibernating bats in Europe are largely unknown. Methodology/Principal Findings We screened hibernacula in the Czech Republic and Slovakia for the presence of the fungus during the winter seasons of 2008/2009 and 2009/2010. In winter 2009/2010, we found infected bats in 76 out of 98 surveyed sites, in which the majority had been previously negative. A photographic record of over 6000 hibernating bats, taken since 1994, revealed bats with fungal growths since 1995; however, the incidence of such bats increased in Myotis myotis from 2% in 2007 to 14% by 2010. Microscopic, cultivation and molecular genetic evaluations confirmed the identity of the recently sampled fungus as G. destructans, and demonstrated its continuous distribution in the studied area. At the end of the hibernation season we recorded pathologic changes in the skin of the affected bats, from which the fungus was isolated. We registered no mass mortality caused by the fungus, and the recorded population decline in the last two years of the most affected species, M. myotis, is within the population trend prediction interval. Conclusions/Significance G. destructans was found to be widespread in the Czech Republic and Slovakia, with an epizootic incidence in bats during the most recent years. Further development of the situation urgently requires a detailed pan-European monitoring scheme.

Extremely low-frequency electromagnetic fields disrupt magnetic alignment of ruminants

Resting and grazing cattle and deer tend to align their body axes in the geomagnetic North-South direction. The mechanism(s) that underlie this behavior remain unknown. Here, we show that extremely low-frequency magnetic fields (ELFMFs) generated by high-voltage power lines disrupt alignment of the bodies of these animals with the geomagnetic field. Body orientation of cattle and roe deer was random on pastures under or near power lines. Moreover, cattle exposed to various magnetic fields directly beneath or in the vicinity of power lines trending in various magnetic directions exhibited distinct patterns of alignment. The disturbing effect of the ELFMFs on body alignment diminished with the distance from conductors. These findings constitute evidence for magnetic sensation in large mammals as well as evidence of an overt behavioral reaction to weak ELFMFs in vertebrates. The demonstrated reaction to weak ELFMFs implies effects at the cellular and molecular levels.

Directional preference may enhance hunting accuracy in foraging foxes

Red foxes hunting small animals show a specific behaviour known as ‘mousing’. The fox jumps high, so that it surprises its prey from above. Hearing seems to be the primary sense for precise prey location in high vegetation or under snow where it cannot be detected with visual cues. A fox preparing for the jump displays a high degree of auditory attention. Foxes on the prowl tend to direct their jumps in a roughly north-eastern compass direction. When foxes are hunting in high vegetation and under snow cover, successful attacks are tightly clustered to the north, while attacks in other directions are largely unsuccessful. The direction of attacks was independent of time of day, season of the year, cloud cover and wind direction. We suggest that this directional preference represents a case of magnetic alignment and enhances the precision of hunting attacks.

Distribution and status of lynx in the border region between Czech Republic, Germany and Austria

This paper summarizes available information concerning the presence of the Eurasian lynxLynx lynx Linneaus, 1758 in the Šumava Mountains and adjacent areas along the common border of Czech Republic, Germany and Austria. Our data give an overview of the lynx population occupying the border region between the three countries from 1990 to 1999. We estimated population size using radiotracking data. From 1990 to 1998, population increased from under 20 to nearly 70 resident animals. During this time, reproduction increased as well, with a maximum of 55 kittens observed in the rearing period of 1998 to 1999. Mortality data indicated that illegal hunting was widespread. Our paper discusses possible links with other lynx populations and describes the legal status of lynx in the three different countries. Current management approaches are outlined and steps toward a long-term conservation plan for the population are proposed.

Dogs are sensitive to small variations of the Earth’s magnetic field

IntroductionSeveral mammalian species spontaneously align their body axis with respect to the Earth’s magnetic field (MF) lines in diverse behavioral contexts. Magnetic alignment is a suitable paradigm to scan for the occurrence of magnetosensitivity across animal taxa with the heuristic potential to contribute to the understanding of the mechanism of magnetoreception and identify further functions of magnetosensation apart from navigation. With this in mind we searched for signs of magnetic alignment in dogs. We measured the direction of the body axis in 70 dogs of 37 breeds during defecation (1,893 observations) and urination (5,582 observations) over a two-year period. After complete sampling, we sorted the data according to the geomagnetic conditions prevailing during the respective sampling periods. Relative declination and intensity changes of the MF during the respective dog walks were calculated from daily magnetograms. Directional preferences of dogs under different MF conditions were analyzed and tested by means of circular statistics.ResultsDogs preferred to excrete with the body being aligned along the North–South axis under calm MF conditions. This directional behavior was abolished under unstable MF. The best predictor of the behavioral switch was the rate of change in declination, i.e., polar orientation of the MF.ConclusionsIt is for the first time that (a) magnetic sensitivity was proved in dogs, (b) a measurable, predictable behavioral reaction upon natural MF fluctuations could be unambiguously proven in a mammal, and (c) high sensitivity to small changes in polarity, rather than in intensity, of MF was identified as biologically meaningful. Our findings open new horizons in magnetoreception research. Since the MF is calm in only about 20% of the daylight period, our findings might provide an explanation why many magnetoreception experiments were hardly replicable and why directional values of records in diverse observations are frequently compromised by scatter.

Magnetic Alignment in Carps: Evidence from the Czech Christmas Fish Market

While magnetoreception in birds has been studied intensively, the literature on magnetoreception in bony fish, and particularly in non-migratory fish, is quite scarce. We examined alignment of common carps (Cyprinus carpio) at traditional Christmas sale in the Czech Republic. The sample comprised measurements of the directional bearings in 14,537 individual fish, distributed among 80 large circular plastic tubs, at 25 localities in the Czech Republic, during 817 sampling sessions, on seven subsequent days in December 2011. We found that carps displayed a statistically highly significant spontaneous preference to align their bodies along the North-South axis. In the absence of any other common orientation cues which could explain this directional preference, we attribute the alignment of the fish to the geomagnetic field lines. It is apparent that the display of magnetic alignment is a simple experimental paradigm of great heuristic potential.

New insight into the role of a base in the mechanism of imine transfer hydrogenation on a Ru(II) half-sandwich complex

Asymmetric transfer hydrogenation (ATH) of cyclic imines using [RuCl(η(6)-p-cymene)TsDPEN] (TsDPEN = N-tosyl-1,2-diphenylethylenediamine) was tested with various aliphatic (secondary, tertiary) and aromatic amines employed in the HCOOH-base hydrogen donor mixture. Significant differences in reaction rates and stereoselectivity were observed, which pointed to the fact that the role of the base in the overall mechanism could be more significant than generally accepted. The hydrogenation mixture was studied by nuclear magnetic resonance (NMR), Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and vibrational circular dichroism (VCD) with infrared spectroscopy. The results suggested that the protonated base formed an associate with the active ruthenium-hydride species, most probably via a hydrogen bond with the sulfonyl group of the complex. It is assumed that the steric and electronic differences among the bases were responsible for the results of the initial ATH experiments.

Eurasian Lynx (Lynx Lynx) and its Chance for Survival in Central Europe: The Case of the Czech Republic

4,873 records of Eurasian lynx occurrence in the Czech Republic (CR) were obtained from 1990. During 1990–1994, the occurrence was recorded in 21.7% of the territory of the CR, during 1995–1999 in 35.6% and during 2000–2001 in 20.5%. The Eurasian lynx population was at its peak in 1997.1998 with abundance 100–150 individuals. The current estimate shows only 80–100 animals. Four of the nine radio-telemetrically monitored Eurasian lynx have probably been illegally shot. Hunters. attitude to the Eurasian lynx was examined on the basis of anonymous questionnaires in the areas of Eurasian lynx occurrence. Only 19.2% of the polled hunters believed the Eurasian lynx to play a positive role in ecosystems, 36.9% of them were aware of concrete cases of illegal hunting and 10.3% of them admitted to killing the Eurasian lynx illegally. Poaching turns out to be the most serious cause of the decrease of Eurasian lynx population in the CR. The attitude of students of game management to the Eurasian lynx was more positive.

Directional compass preference for landing in water birds

IntroductionLanding flight in birds is demanding on visual control of velocity, distance to target, and slope of descent. Birds flying in flocks must also keep a common course of landing in order to avoid collisions. Whereas the wind direction may provide a cue for landing, the nature of the landing direction indicator under windless conditions has been unknown. We recorded and analysed landing directions of 3,338 flocks in 14 species of water birds in eight countries.ResultsWe show that the preferred landing direction, independently of the direction from which the birds have arrived, is along the north-south axis. We analysed the effect of the time of the year, time of the day (and thus sun position), weather (sunny versus overcast), light breeze, locality, latitude, and magnetic declination in 2,431 flocks of mallards (Anas platyrhynchos) and found no systematic effect of these factors upon the preferred direction of landing. We found that magnetic North was a better predictor for landing direction than geographic North.ConclusionsIn absence of any other common denominator determining the landing direction, the alignment with the magnetic field lines seems to be the most plausible if not the only explanation for the directional landing preference under windless and overcast conditions and we suggest that the magnetic field thus provides a landing direction indicator.

Morphologically Uniform Bats Hipposideros aff. Ruber (Hipposideridae) Exhibit High Mitochondrial Genetic Diversity in Southeastern Senegal

Two mitochondrial lineages of bats that are morphologically attributed to Hipposideros ruber have been shown to occur sympatrically in southeastern Senegal. We studied genetic diversity in these bats in the Niokolo Koba National Park using sequences of mitochondrial cytochrome b gene to determine the taxonomic status of the two genetic forms, and included skull morphology for comparison. Detailed multidimensional analysis of skull measurements indicated slight morphological differences between the two genetic forms. Exploration of peak frequency of the constant-frequency echolocation signals in a local population of Hipposideros aff. ruber was not available for both groups. Phylogenetic comparison with other available West African representatives of H. aff. ruber revealed paraphyletic relationship of the two Senegalese forms, with the less abundant form from Senegal forming a monophyletic group with that from Benin. Based on genetic divergence and sympatric occurrence, the two forms from Senegal might represent cryptic species. However, absence of nuclear gene flow between them is yet to be investigated to demonstrate their reproductive isolation.