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Diet of Peregrine Falcons (Falco peregrinus) in relation to temporal and spatial variation in racing pigeon availability in Wales

Abstract

The relative frequency of Common Pigeons Columba livia in the diet of Peregrine Falcons differed across three areas of south-central Wales in line with racing pigeon availability. Peregrines exhibited a functional response to spatial and temporal availability of racing pigeons. During the pigeon-racing season (April–September), pigeons comprised 63% of kills in South Wales where pigeons were most available, 43% in the Brecon Beacons with intermediate availability and 30% in Central Wales, where availability was lowest. The corresponding values outside the pigeon-racing season were 18%, 6% and 5% respectively. We estimate that 92% of pigeons killed by Peregrines were racing pigeons, 7% were feral pigeons and the remainder were other domestic pigeon varieties.

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Spatial and temporal diversity of the diet of the tawny owl (Strix aluco)

Spatial and temporal diversity of the diet of the tawny owl (Strix aluco)

The author compared diet of eight owl species in Slovakia, out of which four species prey in the non-forest environment (Bubo bubo, Tyto alba, Asio otus and Athene noctua), while the other four species prey mostly in the forest (Glaucidium passerinum, Aegolius funereus, Strix uralensis and Strix aluco). Tawny owl (Strix aluco) has shown the highest degree of adaptability when it comes to various types of environment and broad diversity of prey. Appendix 1 presents material of total 225,441 pieces of diet, which contains 69 species of mammals and at least 147 species of birds. While B. bubo diet is typical especially for high presence of bigger prey species within mammals and birds (66 diagnostic taxa), diet of S. aluco is characterized by as many as 89 taxa with higher share than the average of all eight compared owls (taxa with values 1+ and 2+ in blocks as marked by full line). Based on the analysis of 68,070 pieces of S. aluco diet collected in Slovakia, it is possible to differentiate seven basic diet types: A - from lower mountains, B - from middle montane locations, C - from colder and more humid parts of mountains, D - characterized by high share of bats (Chiroptera), E - characterized by high share of slugs (Limacidae), F - from floodplain forests, and finally G - from environment strongly influenced by humans. Diagnostic species for one or several diet types are characterized by markedly higher share than Slovak average. By the large amount of analyzed samples of S. aluco diet it is possible to gain the knowledge about structure of several animal groups from relatively little disrupted forest ecosystems and those from environment to some degree influenced by humans. Diet types represent simplified models, which are understood in a different sense than plant communities. Individual disposition for specific food preference (e. g. Chiroptera) also plays an important role by some tawny owl's specimens. Some types of prey can be further divided into undertypes (e. g. undertypes G1 and G2 in Table 1). Diet of S. aluco has been examined more in detail and over a longer period of time especially in following national parks: Slovenský kras, Muránska planina and Veľká Fatra Mts. Samples from other parts of Slovakia are also presented here according to their relevance to particular diet types. Pellets of S. aluco were collected over a longer period of time (up to 30 years) in several sites and it is chronological periodicity in presentence of diagnostic species, which stands in focus. Long-term changes in S. aluco diet during Holocene were examined in two parts of Veľká Fatra Mts, which are influenced by climatic changes as well as human activity (deforestation and pasture). The author has occasionally collected pellets of S. aluco in several mountains of Europe between Western Alps and Caucasus and from northern border in S. aluco areal, from Trondheim area in Norway. Furthermore, the author presents hereby his own material from pellets of S. aluco from the Middle East to Himalaya (in particular countries of Jordan, Israel, Lebanon, Syria, Turkey, Iran, Kyrgyzstan and Nepal).

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Spatio-temporal variation of throughfall in a hyrcanian plain forest stand in Northern Iran

., Madramootoo, C.A., 2006. Effect of land management on runoff and soil losses from two small watersheds in St Lucia. Land Degrad. Dev., 17, 1, 55-72. DOI: 10.1002/ldr.694. David, J.S., Bellot, J., Birot, Y., David, T.S., 2011. Water fluxes in forests. In: Birot, Y., Gracia, C., Palahi, M. (Eds.): Water for Forests and People in the Mediterranean Region - A Challenging Balance. What Science Can Tell Us? European Forest Institute, Sarjanr, Finland, pp. 32-36. Davudirad, A.A., Sadeghi, S.H.R., Sadoddin, A., 2015. Monitoring temporal and spatial

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Distributed scheduling of measurements in a sensor network for parameter estimation of spatio-temporal systems

-137. Patan, M. (2006). Optimal activation policies for continuous scanning observations in parameter estimation of distributed systems, International Journal of Systems Science 37(11): 763-775. Patan, M. (2008). A parallel sensor scheduling technique for fault detection in distributed parameter systems, in E. Luque et al. (Eds.), Parallel Processing-Euro Par 2008, Lecture Notes in Computer Science, Vol. 5168, Springer, Berlin/Heidelberg, pp. 833-843. Patan, M. (2012a). Distributed scheduling of sensor networks for identification of spatio-temporal

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The Temporal Perspective in Higher Education Learners: Comparisons between Online and Onsite Learning

. Díaz-Morales, J. F. (2006). Estructura factorial y fiabilidad del Inventario de Perspectiva Temporal de Zimbardo. In Psicothema, 18(3), (pp. 565-571). 25. Eren, A. (2009). Exploring the effects of changes in future time perspective and perceived instrumentality on graded performance. In Electronic Journal of Educational Research, 19(7), (pp. 1217-1248). 26. Evans, T.N. (2009). An investigative study of factors that influence the retention rates in online programs at selected state, state-affiliated, and private universities. PhD

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Sediment geochronology and spatio-temporal and vertical distributions of radionuclides in the Upper Bonny Estuary (South Nigeria)

Abstract

Surface deposits and sediment cores were collected from the Upper Bonny Estuary, located in Southwest Nigeria, and analyzed to determine spatio-temporal and vertical distributions of radio-nuclide activities expressed in Bq·kg−1 dry weight. The results of activities of naturally occurring radionuclides of 226Ra (15 ± 2–34 ± 3 Bq·kg−1), 228Ra (32 ± 5–48 ± 6 Bq·kg−1), 40K (264 ± 29–462 ± 36 Bq·kg−1) were found to be all within the range of typical values reported for coastal regions. Ratios of 226Ra to 228Ra suggested accretion for all samples with low sediment accumulation registered during rainy months. In addition, vertical distributions at the three sampling sites were also studied with the initial aim of establishing chronologies from the decay of excess 210Pb. In two cores, excess 210Pb, estimated by subtracting 226Ra from total 210Pb on a layer-by-layer basis, exhibit relatively constant activity with discrete minima and maxima. Therefore, these cores were excluded from radiometric dating. Only the third core could be dated by the constant rate of supply model, and 137Cs was utilized to validate the 210Pb chronology.

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Spatial and temporal plant phenological niche differentiation in the Wadi Degla desert ecosystem (Egypt)

References ABBAD, A., BENCHAABANE, A., 2004: The phenological study of Atriplex halimus L. African Journal of Ecology 42, 69-73. ÅGREN, J., EHRLEN, J., SOLBRECK, C., 2008: Spatio-temporal variation in fruit production and seed predation in a perennial herb influenced by habitat quality and population size. Journal of Ecology 96, 334-345. AUGSPURGER, C. K., 1983: Phenology, flowering synchrony and fruit set of six neotropical shrubs. Biotropica 15, 257-267. AYYAD, M., ABDEL-RAZIK, M

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Temporal analysis of urban changes and development in Warsaw’s ventilation corridors

References Alanen, AR 1992, ‘MODEL COMMU NITIES: THE GA RDEN CITY MOVEME NT IN AU STRAL IA’, Landscape Journal , vol. 11, no. 2, pp. 188–190. <10.3368/lj.11.2.188>. Amati, M & Yokohari, M 2006, ‘Temporal changes and local variations in the functions of London’s green belt’, Landscape and urban planning , vol. 75, no. 1, pp. 125–142. Available from: < http://www.sciencedirect.com/science/article/pii/S0169204605000101 >. [16 September 2014]. Blaschke, T 2010, ‘Object based image analysis for remote sensing’, ISPRS journal of photogrammetry and

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On The Estimation of Temporal Changes of Snow Water Equivalent by Spaceborne Sar Interferometry: A New Application for the Sentinel-1 Mission

Abstract

In this work we present a methodology for the mapping of Snow Water Equivalent (SWE) temporal variations based on the Synthetic Aperture Radar (SAR) Interferometry technique and Sentinel-1 data. The shift in the interferometric phase caused by the refraction of the microwave signal penetrating the snow layer is isolated and exploited to generate maps of temporal variation of SWE from coherent SAR interferograms. The main advantage of the proposed methodology with respect to those based on the inversion of microwave SAR backscattering models is its simplicity and the reduced number of required in-situ SWE measurements. The maps, updated up to every 6 days, can attain a spatial resolution up to 20 m with sub-centimetre ΔSWE measurement accuracy in any weather and sun illumination condition. We present results obtained using the proposed methodology over a study area in Finland. These results are compared with in-situ measurements of ΔSWE, showing a reasonable match with a mean accuracy of about 6 mm.

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Development of Tourist Traffic in the Regions of the European Union in 2000–2015 – A Spatial and Temporal Analysis

Activity of OECD Countries Using Spatio-Temporal Methods. Dynamic Econometric Models, 9, 91-98. Szromek, A.R. (2013). Wskaźniki funkcji turystycznej i ich współzależność z innymi wskaźnikami ekonomicznymi na przykładzie polskiej gospodarki w latach 2000-2010, Prace Naukowe Uniwersytetu Ekonomicznego we Wrocławiu, 304, 338-345.

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