Farmland bird populations in Europe are shrinking, largely due to modern agriculture practices. In grasslands, the shift to early mowing is believed to be particularly responsible for this decline because it is interwoven with breeding time-a change that birds in general have not adapted to. We studied the post-fledging survival of the Whinchat, an altricial grassland passerine. Based on a sample of 74 radiotagged young Whinchats, we confirmed that they fledge at 13-15 days. Twenty-four fledged birds died, while 18 of them were depredated. The survival probability of young Whinchats, calculated using Kaplan-Meier estimates, was lowest during the first day after fledging, and slowly leveled off later. In total, the probability that a juvenile survived the first month after fledging was 0.52. During the first days after fledging, all chicks were found hiding on the ground among the grass stubble. The generalized linear mixed model predicts that half of the fledglings at 20 days old and 20% at 22 days old (8-10 days after fledging) will not escape but will instead remain still when approached by a threat. Sixteen depredations occurred during this period, all by mammal predators. Afterwards, the fledglings changed their strategy, escaping through flight. After 12 days, more and more of the chicks were found exposed on top of the grass or on the bush instead of hiding on the ground. The transition from sit and hide to escape behavior reduced the predation rate considerably. Only two chicks were depredated later, both by an avian predator. Due to the initial predator avoidance strategy, the current conservation measure (to postpone mowing until the chicks in 80% of all nests have fledged) is not sufficient to halt population decline on improved meadows. We suggest that at least 10 days more, and possibly even 14 days more, are necessary to maintain viable Whinchat populations.Zusammenfassung Die Praktiken in der modernen Landwirtschaft führen in Europa zu einer Abnahme der Vogelpopulationen auf Ackerland. Vor allem der Wechsel hin zu früher Gras-Mahd wird dafür verantwortlich gemacht, weil diese immer häufiger in die Brutzeit fällt-eine Veränderung, an die sich die Vögel nicht anpassen konnten. Wir untersuchten das Ü berleben in der Zeit direkt nach dem Flüggewerden bei Braunkehlchen, einem Nesthocker unter den auf Wiesen lebenden Singvögeln. Anhand von 74 mit Sendern versehenen, jungen Braunkehlchen konnten wir bestätigen, dass sie im Alter von 13 bis 15 Tagen flügge werden. 24 der markierten Vögel fielen aus, weil sie starben; 18 von ihnen wurden erbeutet. Die Ü berlebenswahrscheinlichkeit der jungen Braunkehlchen wurde mit der Kaplan-Meier-Methode eingeschätzt; sie war in den ersten fünf Tagen nach dem Flüggewerden am niedrigsten und pendelte sich danach langsam ein. Insgesamt lag die Ü berlebenswahrscheinlichkeit für den ersten Monat nach Flüggewerden bei 0,52. In den ersten Tagen versteckten sich alle Küken zwischen den Grasstoppeln am Boden. Das generalisierte lineare gemischte Modell (GLMM) sagt voraus, dass 50%...

Population dynamics of the White StorkCiconia ciconiain Slovenia between 1999 and 2010Between 1999 and 2010, an annual census of the White StorkCiconia ciconiabreeding population was carried out in Slovenia using standardised methods. The Stork's population was concentrated in the NE and SE parts of Slovenia. In the 1999-2010 period, the breeding range of its population in Slovenia expanded in NW direction (the Savska ravan region), in SW direction (the Notranjsko podolje and Pivško podolje regions), but the species also colonized a part between Central and SE Slovenia (Dolenjsko podolje). Between 193 and 240 pairs were breeding during the study period, 209 pairs on average (HPa). The largest number of breeding pairs was recorded in 2004, the smallest in 2005. During the study period, breeding pairs (HPa) occupied 350 discrete nests in total. Average number of breeding pairs that raised juveniles (HPm) was 161. The highest fecundity was recorded in 2004, when 534 juveniles (JZG) fledged, the lowest in 2006, with only 219 fledged juveniles. On average, 414 juveniles fledged per year. The breeding pairs' (JZa) average breeding success in these 12 years was 2.02, the highest in 2000 (2.41), the lowest in 2006 (1.09). Average breeding success for the successful breeding pairs (JZm) was 2.57. The highest was in 2007 (2.94), the lowest in 2006 (2.07). The largest number of breeding pairs in 2004 and 2008 can be explained by the favourable fecundity in the population in 2000 and 2004, as juveniles become sexually mature at the age of 3-5 years, and at that age they generally return to the breeding grounds for the first time. The lowest number of breeding pairs and poor breeding success in 2005 and 2006 was caused by late arrival of White Storks to the breeding grounds and by unfavourable weather conditions during the breeding period. The pattern of nests placement did not change generally during the last 12 years. The largest proportion of nests was positioned on various kinds of poles (81%) and on chimneys (18%). In total, 27 area surveyors and 239 assistants helped in census realisation.

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