Summary
1.A central question in ecology is to separate the relative contribution of density dependence and stochastic influences to annual fluctuations in population size. Here we estimate the deterministic and stochastic components of the dynamics of different European populations of white stork Ciconia ciconia . We then examined whether annual changes in population size was related to the climate during the breeding period (the 'tap hypothesis' sensu Saether, Sutherland & Engen (2004, Advances in Ecological Research , 35 , 185-209) or during the nonbreeding period, especially in the winter areas in Africa (the 'tube hypothesis'). 2. A general characteristic of the population dynamics of this long-distance migrant is small environmental stochasticity and strong density regulation around the carrying capacity with short return times to equilibrium. 3. Annual changes in the size of the eastern European populations were correlated by rainfall in the wintering areas in Africa as well as local weather in the breeding areas just before arrival and in the later part of the breeding season and regional climate variation (North Atlantic Oscillation). This indicates that weather influences the population fluctuations of white storks through losses of sexually mature individuals as well as through an effect on the number of individuals that manages to establish themselves in the breeding population. Thus, both the tap and tube hypothesis explains climate influences on white stork population dynamics. 4. The spatial scale of environmental noise after accounting for the local dynamics was 67 km, suggesting that the strong density dependence reduces the synchronizing effects of climate variation on the population dynamics of white stork. 5. Several climate variables reduced the synchrony of the residual variation in population size after accounting for density dependence and demographic stochasticity, indicating that these climate variables had a synchronizing effect on the population fluctuations. In contrast, other climatic variables acted as desynchronizing agents. 6. Our results illustrate that evaluating the effects of common environmental variables on the spatio-temporal variation in population dynamics require estimates and modelling of their influence on the local dynamics.
Summary1. The timing of bird migration has shifted in response to climate change. However, few studies have linked the potential consequences of any phenological shift on individual fitness and even fewer have disentangled the role of plasticity and microevolution in the observed shifts. 2. The arrival date and breeding success of white storks (Ciconia ciconia) have been recorded since the 1880s in Slovakia. We used data for two periods (1895-1913 and 1977-2007), which were considered, respectively, as populations before and after the start of climate warming. About 4000 male and 2500 female arrival dates along with 3000 breeding attempts were studied. 3. Mean arrival dates did not differ between the two periods. During 1977-2007, males tended towards a slight delay for most fractions of arrival distribution. Protandry was reduced by 30% (1Á44 days). 4. In both sexes, the early percentiles of the arrival distribution arrived later those years with warmer temperatures at the African wintering grounds, while late percentiles advanced their arrival when temperatures were higher in the European areas flown over during migration. 5. Mean breeding success of the Slovakian population has not changed since 1977. However, fecundity selection for arrival date reduced over the years: at the end of 1970s and 1980s, early breeders had more success than late breeders, but this seasonal trend disappeared towards the end of the study period. An early arrival and territory acquisition may have become less of an advantage due to the enhancement of feeding opportunities during the breeding season in recent decades. 6. A century ago, stork arrival varied spatially, with earlier arrivals at low altitudes, southern slopes and warmer and drier regions. This spatial variation mostly vanished, and at present, we found little correlations with topographical and climatic gradients. 7. We showed that long-term temporal changes in the timing of biological events may be complex because each fraction of a population and sex may show different temporal trends in their arrival dates. In addition, the effect of biotic and abiotic factors may change consistently in space and time, and thereby phenotypes' value depends on the circumstances that are expressed due to its variable fitness consequences.
Changes in the spring arrival dates of migrant birds have been reported from a range of locations and many authors have focused on long-term trends and their relationship to temperature and other climatic events. Perhaps more importantly, changed arrival dates may have consequences for the breeding dates of birds which strongly influence breeding success. In this paper we take the opportunity provided by a monitoring scheme of the white stork (Ciconia ciconia) to examine several features of the timing of arrival and breeding in relation to chick production in Slovakia during the period 1978-2002. First arrival dates ranged from 5 th March to 30 th April, and hatching dates varied between 26 th April and 8 th July. Generally, early arriving pairs started breeding earlier and a shorter interval between the arrival of the first partner and breeding, expressed here as hatching date, resulted in higher breeding success.
The available keys for European Hippoboscidae are outdated and do not cover all species currently known from Europe. Therefore, identification keys to the eleven genera and 31 species of the European hippoboscids are provided here. Ornithomya comosa (Austen, 1930) (Diptera: Hippoboscidae) is recorded for the first time from the territory of Slovakia based on one female found on a sand martin, Riparia riparia (Linnaeus, 1758). The list of keds and louse flies recorded from the territory of Slovakia is increased to 20 species. New host records for Slovakia are presented.
Hniezdne spoločenstvá vtákov vo vzťahu k štruktúre urbánneho prostredia malého mesta (Sabinov, východné Slovensko) Breeding bird communities in relation to structure of urban environment of a small town (Sabinov, E Slovakia
We detected occurrence and nesting of Eurasian Craig Martin (Ptyonoprogne rupestris) for the first time in Slovakia. One nesting pair with four juveniles was detected during the 2022 nesting season in the Malá Fatra mountains. This finding is urging for more detailed research in other mountain areas taking into consideration the expansion of its population in Europe.
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