Four-year satellite tracking of a White Stork Ciconia ciconia since independence : description of an odyssey

Ein nestjunger Weißstorch aus der Gegend von Kaliningrad, Russland, wurde im Juli 2000 in der Biologischen Station Rybatschij aufgezogen und im September verspätet freigelassen. Im Rahmen eines Projektes zur Untersuchung des Orientierungsvermögens wurde er mit einem Satellitensender (14554) ausgestattet. Obwohl die Weißstörche aus dem Kaliningrader Gebiet normalerweise nach SO ziehen, wanderte der besenderte Vogel nach SW ab, überquerte das Mittelmeer von Frankreich nach Tunesien, verbrachte seinen ersten Winter und zweiten Sommer in Nordafrika und seinen zweiten Winter im Tschad-See-Gebiet im Norden von Nigeria und Kamerun. Im Sommer 2002 hielt er sich auf der Iberischen Halbinsel auf, im Winter 2002/2003 im äußersten Süden Spaniens. Im Sommer 2003 kehrte der Storch im Alter von 3 Jahren in das Verbreitungsgebiet osteuropäischer Weißstörche zurück – nach Nordpolen, nur 220 km südwestlich von seinem Geburtsort, wo er möglicherweise brütete. Der Wegzug 2003 verlief über die für osteuropäische Weißstörche typische Ostroute. In Afrika zog der Storch weit nach Westen – bis in den West-Tschad – sodass sich sein Winterquartier nur 175 km von dem Gebiet entfernt befand, das er 2002 über die Westroute erreicht hatte.A White Stork from the Kaliningrad region of Russia was taken into captivity as a nestling in 2000, raised at the Biological Station Rybachy and released after a retention experiment in September. The bird was tagged with a satellite transmitter 14554 as part of an investigation of the orientation abilities of juvenile White Storks. In the first autumn, the bird moved towards the SW, even though the normal migratory direction for the storks from Kaliningrad is SE. The bird crossed the Mediterranean from France to Tunisia, and spent its first winter and second summer in North Africa. It spent its second winter in the Lake Chad area, in northern Nigeria and Cameroon. In summer 2002 it was in the Iberian peninsula, in winter 2002/2003 in the southernmost part of Spain. At the age of 3 years this bird returned to the distribution area of East European White Storks. It spent the summer (possibly bred) in northern Poland, 220 km SSW of its natal site. Autumn migration 2003 followed the eastern flyway typical of East European White Storks. When in Africa, the bird moved far to the W, to western Chad, so that its wintering area 2003 was only 175 km away from the area that had been reached in 2002 via the western flyway

Modeling of trawl doors with account of the currents

Mathematical model of trawl doors is presented and methods of their modeling with account of the water currents are described. The model could be used for optimal tooling of trawl systems for real environments

Experience of socio-philosophical research of post-Soviet religiosity: specificity and methodological basis

The article provides a methodological basis for socio-philosophical research through the acceptance of freedom. The aim of the research is to develop an algorithm for analyzing religious and metaphysical views, which allows to formulate a holistic and meaningful idea of the spiritual sphere of life in a post-secular society, including the Russian society of the post-Soviet period. The review of the main approaches to the description of the religiosity of the population, which were used by Russian authors in the study of the post-Soviet period, is given in the article. The disadvantages of these methods are pointed out: the formality of the separation on confessional grounds, attempts to unambiguously associate a person with any religious organization, the intention to reduce the description to quantitative indicators, the ability for interested parties to interpret the results in their benefit. It makes impossible for researchers to fix many essential characteristics of religiosity, such as the degree of influence of faith on social behavior, the moral development of an individual, his attitude to bearer of other views, denominations and cultures. Thus, the relevance of problem of finding new approaches to the study of religiosity is demonstrated. As an alternative, a qualitative comprehensive analysis of religious and metaphysical ideas is proposed. It based on the socio-philosophical concept of 10 degrees of freedom-independence, developed by the Doctor of Philosophical Sciences A. G. Myasnikov. The hierarchy of freedom’s degrees, where moral and religious freedom-independence occupies the 8th level, is described. The main aspects of the concept are given. The research direction of the religiosity of the population is outlined. The aspects that should be considered during the analysis are considered in detail, including the complexity and internal consistency of religious and metaphysical ideas, the area of their practical application, etc. From the viewpoint of analyzing the society’s structure, it is proposed to consider a person as a carrier of a certain type of religiosity. This term denotes a collective characteristic that includes self-identification, dogmatic, cult, moral, behavioral and other aspects of a person’s spiritual life. In conclusion, some estimates, which are based on the results of the analysis of post-Soviet religiosity based on the concept of 10 degrees of freedom-independence, are given. It is indicated that this approach allows to consider the essential aspects of a person’s religiosity, the mechanisms of its formation, and provide to determine to what extent the conditions of society and the state contribute to the comprehensive development of the individual. The conclusion is made about the high heuristic potential of the proposed methodology. It is noted that in the course of further research additional factors may be identified, the analysis of which will allow to form a more accurate and meaningful vision of religious and metaphysical ideas

Migratory Eurasian reed warblers can use magnetic declination to solve the longitude problem

The longitude problem (determining east-west position) is a classical problem in human sea navigation. Prior to the use of GPS satellites, extraordinarily accurate clocks measuring the difference between local time and a fixed reference (e.g., GMT) [1] were needed to determine longitude. Birds do not appear to possess a time-difference clock sense [2]. Nevertheless, experienced night-migratory songbirds can correct for east-west displacements to unknown locations [3-9]. Consequently, migratory birds must solve the longitude problem in a different way, but how they do so has remained a scientific mystery [10]. We suggest that experienced adult Eurasian reed warblers (Acrocephalus scirpaceus) can use magnetic declination to solve the longitude problem at least under some circumstances under clear skies. Experienced migrants tested during autumn migration in Rybachy, Russia, were exposed to an 8.5° change in declination while all other cues remained unchanged. This corresponds to a virtual magnetic displacement to Scotland if and only if magnetic declination is a part of their map. The adult migrants responded by changing their heading by 151° from WSW to ESE, consistent with compensation for the virtual magnetic displacement. Juvenile migrants that had not yet established a navigational map also oriented WSW at the capture site but became randomly oriented when the magnetic declination was shifted 8.5°. In combination with latitudinal cues, which birds are known to detect and use [10-12], magnetic declination could provide the mostly east-west component for a true bi-coordinate navigation system under clear skies for experienced migratory birds in some areas of the globe

Spatial distribution of breeding Pied Flycatchers Ficedula hypoleuca in respect to their natal sites

Study of philopatry and dispersal of pied flycatchers Ficedula hypoleuca was launched on the Courish Spit (SE Baltic) in 1981. Since then, ca. 9,000 nestlings were ringed at different sites in the Russian part of the Courish Spit. A total of 557 individuals ringed as pulli were recaptured in subsequent seasons in the study area. Both males and females are more often recaptured in the plots where they were ringed than in other plots. These results were interpreted in the framework of the hypothesis forwarded by Löhrl (1959) and supported by Berndt & Winkel (1979). These authors suggested that cavity nesters (pied flycatchers and collared flycatchers F. albicollis) imprint their future local breeding area during the period of postfledging exploration. Birds that survive until the next spring, return to these imprinted areas to breed. A similar study done by Sokolov et al. (1984) on the Courish Spit in an open nesting species, the chaffinch Fringilla coelebs, confirmed this finding. We assumed that juvenile pied flycatchers disperse for varying distances during their postfledging movements and imprint a local area, some 1–5 kilometres in diameter. This area is the goal of their migration next spring. It is suggested that in spring, yearlings are non–randomly distributed in respect to the area they have imprinted as juveniles. Recently, Vysotsky (2000, 2001) re–analysed the same data on philopatry of pied flycatchers on the Courish Spit and forwarded an alternative hypothesis. He suggests that juveniles, both males and females, do not imprint any local area during the postfledging period, but are distributed randomly across the area of several dozens of kilometres in spring. Vysotsky was able to show that distribution of distances of natal dispersal did not differ from the random pattern the study plot which was an 8.5 km long line of nest boxes along the Courish Spit. The aim of this study was to test these two alternative hypotheses. To do so, we set up nine new study plots in 2000. Over 800 nest–boxes were made available for the birds (in addition to the old 400) in the 44 km long area. We recaptured pied flycatchers returning for breeding during four years, 2000–2003. The distribution of natal dispersal distances was compared with the null model which assumes that pied flycatchers settle randomly in the study area. We took all nest boxes from which pied flycatchers successfully fledged in a particular year and all next boxes where we were able to capture either a male or a female in the subsequent year, and calculated the distances between each pair of such nest boxes. Simulations were run separately for each sex. Theoretical distributions already include control efficiency. If some nest boxes were not checked in some year, or if we failed to capture one or both members of a breeding pair, we did not include this nest box in the model. Some birds could settle outside the study plot. Therefore, the theoretical distribution may underestimate the actual range of natal dispersal, but is unlikely to overestimate it. The number of females ringed as nestlings and recaptured as one–year–old birds was 43. The distribution of their natal distances (mean 6,8 km, SE = 0,81; median 5,4 km) was not significantly different from the pattern predicted by the null model (Wilcoxon matched pairs test: z = 1,25; p = 0,21). Conversely, males settled significantly closer to their natal nest box (n = 83; mean 4,3 km, SE = 0,57; median 2,5 km) than predicted by the model (Wilcoxon matched pairs test: z = 2,45; p = 0,014). For example, 24% of males settle within one km from their natal site, as compared with 7% predicted by the model. Males are found with a greater than chance probability within the 7 km zone around their natal site. The hypothesis by Vysotsky (2000) can thus be rejected for pied flycatcher males. Pied flycatcher females are known to settle at larger distances from their natal nest box. The very fact that were controlled 83 males and only 43 females suggests, assumed that sex ratio at fledging is close to being equal and that true survival rates during the first year of life do not differ greatly between the sexes, that many females emigrated from of our study plot. This does not mean that juvenile females do not imprint a home area during the postfledging period, as suggested by Vysotsky (2000). We think that the reason for this is not the inadequate navigational ability of the females but the fact that they were attracted by a prospecting male at some distance from their migratory destination and settle there. Such intercepting was suggested by Fedorov (1996) for Acrocephalus warblers, and it may exist in other migratory passerines. This is supported by the data on natal site fidelity from Spain which show that in Spanish pied flycatcher populations, recruitment rate did not differ between female and male juveniles (Potti & Montalvo, 1991). Females from these southern populations have a limited chance to be attracted by prospecting males in even more southern areas

Navigation by extrapolation of geomagnetic cues in a migratory songbird

Displacement experiments have demonstrated that experienced migratory birds translocated thousands of kilometers away from their migratory corridor to unfamiliar areas can orient towards and ultimately reach their intended destinations. This implies that they are capable of “true navigation”, commonly defined as the ability to return to a known goal after displacement to a completely unknown location without relying on familiar surroundings, cues that emanate from the destination, or information collected during the outward journey. In birds, true navigation appears to require previous migratory experience, and it is generally assumed that, to correct for displacements outside the familiar area, birds initially have to gather information within their year-round distribution range, learn predictable spatial gradients of some environmental cues within it and extrapolate from those to cues of unfamiliar magnitude ̶ the gradient hypothesis. However, the nature of the cues used, and evidence for actual extrapolation remains elusive. Geomagnetic cues (inclination, declination and total intensity) provide predictable spatial gradients across large parts of the globe and could serve for navigation. We tested the orientation of long-distance migrants, Eurasian reed warblers (Acrocephalus scirpaceus), exposing them to geomagnetic cues of unfamiliar magnitude only encountered beyond their natural distribution range. The birds demonstrated re-orientation towards their natural migratory corridor as if they were translocated to the corresponding geographic location but only when all naturally occurring magnetic cues were presented, not when declination was changed alone. This result represents direct evidence for migratory birds’ ability to navigate using geomagnetic cues extrapolated beyond the range of magnitude they previously experienced

Migratory Reed Warblers Need Intact Trigeminal Nerves to Correct for a 1,000 km Eastward Displacement

Several studies have shown that experienced night-migratory songbirds can determine their position, but it has remained a mystery which cues and sensory mechanisms they use, in particular, those used to determine longitude (east-west position). One potential solution would be to use a magnetic map or signpost mechanism like the one documented in sea turtles. Night-migratory songbirds have a magnetic compass in their eyes and a second magnetic sense with unknown biological function involving the ophthalmic branch of the trigeminal nerve (V1). Could V1 be involved in determining east-west position? We displaced 57 Eurasian reed warblers (Acrocephalus scirpaceus) with or without sectioned V1. Sham operated birds corrected their orientation towards the breeding area after displacement like the untreated controls did. In contrast, V1-sectioned birds did not correct for the displacement. They oriented in the same direction after the displacement as they had done at the capture site. Thus, an intact ophthalmic branch of the trigeminal nerve is necessary for detecting the 1,000 km eastward displacement in this night-migratory songbird. Our results suggest that V1 carries map-related information used in a large-scale map or signpost sense that the reed warblers needed to determine their approximate geographical position and/or an east-west coordinate

Habitat use by Siberian warbler species at a stopover site in Far Eastern Russia

Knowledge of the routes and habitat use of Siberian songbird species during migration is very limited. The goal of our study was to describe the autumnal habitat use of seven Siberian warbler species in the genera Phylloscopus, Acrocephalus, Iduna and Locustella in Far Eastern Russia. A total of 2283 individuals were trapped in mist nets placed within different habitat types between 2012 and 2014 as part of the Amur Bird Project at Muraviovka Park in Far Eastern Russia. We studied the effect of habitat type and vegetation height on the occurrence of each species, and compared our results to published information on habitat use on the breeding grounds. Our results demonstrate that most species exhibit species-specific preferences for habitat type, and that these stopover habitats were similar to habitats used on the breeding grounds. © 2018 British Trust for Ornitholog