Ornis Fennica https://ornisfennica.journal.fi/ <p>Ornis Fennica is a peer-reviewed international ornithological journal published by BirdLife Finland.</p> BirdLife Finland en-US Ornis Fennica 0030-5685 Spring migration phenology of Eurasian Woodcocks tagged with GPS-Argos transmitters in Central Europe https://ornisfennica.journal.fi/article/view/121933 <p>Eurasian Woodcock (<em>Scolopax rusticola</em>) plays a special role in the cultural heritage of most nations in Europe. In the last decade, ringing revealed the main migratory patterns of some well studied and intensively harvested Woodcock populations wintering in Western and Southern Europe. The same study sites and populations were in focus when the recently revolutionized satellite tracking technologies allowed the study of individual migrations. In contribution to these efforts, we present here the pre-nuptial migration data of Woodcocks captured and tagged with GPS-Argos transmitters in Central Europe, in 2020. Woodcocks migrated from the tagging site in Hungary to Ukraine, European Russia and Central Siberia by an average of 2,678 km (range 677–5,002 km). The duration of the migration ranged between 1–52 days, the overall migration speed was 382 km/day, the absolute maximum distance covered in a day was 866 km. The individual number of stopovers varied during the migration from 0 to 5. The average time spent at each stopover site was 5.6 days. Within the stopover sites, the daily displacements ranged between 11–3,329 m. The Carpathian Basin may be more important in the wintering of Woodcocks than previously assumed, as tagged birds stayed significantly longer compared to any later en route migratory stopover. In accordance with the results of previous DNA analysis, identified breeding grounds of tagged individuals represented a large part of the distribution area.</p> Gergely Schally Sándor Csányi Péter Palatitz Copyright (c) 2022 Gergely Schally, Sándor Csányi, Péter Palatitz https://creativecommons.org/licenses/by/4.0 2022-12-30 2022-12-30 99 4 104 116 10.51812/of.121933 Age and sex ratios in the declining West Siberian/North European population of Long-tailed Duck wintering in the Baltic Sea https://ornisfennica.journal.fi/article/view/113681 <p>The West Siberian/North European population of Long-tailed Duck (<em>Clangula hyemalis</em>), which breeds in the Russian Arctic and northern Fennoscandia and winters in the Baltic Sea, has declined rapidly since the 1990s. To identify the causes of the decline and initiate effective conservation measures information on basic demographic parameters is needed. A photo survey method was used to estimate female age ratios and the proportion of males among adults in wintering Long-tailed Ducks at coastal and off-shore areas in the Baltic Sea. Female age ratios were defined as the number of first winter males, assumed equal to the number of first winter females, per adult female. Several thousand individuals were sampled each winter from 2008 to 2021. Female age ratios fluctuated between years and were consistently lower in the southern than in the central Baltic Sea. The proportion of males among wintering adults birds was male-biased, more so in the southern Baltic Sea than in other regions. A population model was used to analyse if low female age ratios between 2008 and 2021 has constrained population growth. Given that the estimated weighted mean female age ratio of 0.153 was representative at the population scale, an extremely high adult female mean annual survival rate of 0.872 would have been needed to maintain a stable population. Considering known sources of anthropogenic mortality in the Baltic Sea, and instead assuming a more realistic survival rate of <em>ca.</em> 0.80, a population decline of <em>ca.</em> 7.7% per year should have occurred during the study period.</p> Kjell Larsson Copyright (c) 2022 Kjell Larsson https://creativecommons.org/licenses/by/4.0 2022-12-30 2022-12-30 99 4 117 131 10.51812/of.113681 Influence of habitat quality and diversity on two populations of Eurasian curlew (Numenius arquata) with contrasting dynamics in Western France https://ornisfennica.journal.fi/article/view/124713 <p>Like most shorebirds in Europe, breeding populations of Eurasian curlew (<em>Numenius arquata</em>) are suffering from habitat loss and degradation mainly caused by changes in agricultural practices. In Deux-Sèvres (France), the number of pairs has gradually declined since the early 2000s in the main, historical breeding site, while a new breeding site has appeared recently 80 kilometres further north with increasing number of pairs through the survey period. Many wheat fields and rare dry grasslands are found in the north, whereas the landscape in the south is mainly composed of tillage plots, hay meadows, and pastures. This study aims to highlight differences in food availability and quality between the two areas. Sample series of ground-dwelling and vegetation-dwelling invertebrates were carried out during three key stages of the species breeding cycle with pitfall traps and sweep nets. Dry grasslands in the north were found to be the most favourable habitat in terms of prey availability for adults and for chicks during the brood-rearing period. Moreover, hay meadows and pastures in the south seemed to be resource-abundant feeding habitats. Therefore, the habitats of the northern site seem to offer a greater abundance of invertebrates and thus a potentially larger food resource than the southern one. It follows that the northern site likely offers better breeding conditions, especially for the growth of chicks. An increase in the area of dry grasslands in the north and the establishment of adapted agricultural management in the south would be favourable for the conservation of local curlew populations.</p> Raphaël Leprince Etienne Debenest Christophe Lartigau Victor Turpaud-Fizzala Cyrille Poirel Nicolas Lachaussée Marie Donnez Pierrick Bocher Copyright (c) 2022 Raphaël Leprince, Etienne Debenest, Christophe Lartigau, Victor Turpaud-Fizzala, Cyrille Poirel, Nicolas Lachaussée, Marie Donnez, Pierrick Bocher https://creativecommons.org/licenses/by/4.0 2022-12-30 2022-12-30 99 4 132 149 10.51812/of.124713 Spatial ecology of the Red Kite (Milvus milvus) during the breeding period in Spain https://ornisfennica.journal.fi/article/view/124714 <p>Studies focusing on the spatial ecology of the Red Kite (<em>Milvus milvus</em>) during the breeding season are scarce, despite this season having major importance in its conservation. Spain has one of the largest breeding populations of this species, but it is very threatened in this country. Here, 28 Red Kites were tagged in Spain with GPS satellite transmitters to study the movements of breeding adults during the breeding season (March-June), evaluating the differences according to sex, and investigating the habitat selection. The area used by females was smaller than the used by males (95% KDE = 4.48 vs. 3.30 km<sup>2</sup>). Females also traveled less distance per hour and remained closer to the nest. Thus, females had a higher frequency of locations at distances &lt;250 m from the nest, while males had a higher frequency at distances &gt;1 km. Distances recorded at &gt;5 km were scarce for both sexes, and maximum distances reached were usually (61% of seasons) less than 15 km. Both sexes increased the frequency of movements between 1–3 km during the central hours of the day. Red Kites mainly used areas occupied by non-irrigated arable land, forests, scrubs, and herbaceous vegetation. The selection of certain types of crops highlights the importance of the agroforestry landscape for the conservation of the species. On the other hand, we documented for the first time how part of the Spanish breeding population is a short-distance migrant within the Iberian Peninsula while other part of the population makes post-breeding movements during summer.</p> Jorge García-Macía Javier Vidal-Mateo Javier de la Puente Ana Bermejo Vicente Urios Copyright (c) 2022 Jorge García-Macía, Javier Vidal-Mateo, Javier de la Puente, Ana Bermejo, Vicente Urios https://creativecommons.org/licenses/by/4.0 2022-12-30 2022-12-30 99 4 150 162 10.51812/of.124714 Diet and grit characteristics in young Eurasian Bullfinches (Pyrrhula pyrrhula) inhabiting Iberian hedgerows https://ornisfennica.journal.fi/article/view/124715 <p>For the first time, the diet of young Iberian Bullfinches (<em>Pyrrhula pyrrhula iberiae</em>) is studied, specifically in a hedgerow habitat in northwestern Spain, through stomach (younger nestlings up to 8 d of age, which died without researcher intervention) and faecal sac (older nestlings) analysis, and secondarily direct observation (nestlings and dependent juveniles). Also, for the first time, grit use by bullfinch nestlings is described in some detail. Bullfinches fed their young with a mixture of seeds and invertebrates, with greater quantitative importance of the former. The identity of the seeds varied considerably between spring and summer, and animal fraction gradually decreased from May to July for older nestlings, in both cases presumably because of the seasonal changes in food availability. Caterpillars and spiders were the most important arthropod prey in the diet. Apparently, the young were not fed non-arthropod invertebrates. The relative importance of invertebrates, which are very rich in proteins, was greater for younger nestlings than for older ones. Difficult to digest hard-bodied prey, such as beetles, were not present in the stomachs of the youngest nestlings. The frequency of occurrence and amount of grit in stomachs increased with nestling age, along with the need to grind food. There were no remarkable differences in number of units, size, or number of colour types of gastroliths between months. The high floristic diversity in the study area, which has great overall conservation value, provides a wide range of resources for bullfinches, including plenty of food for their young.</p> Ángel Hernández Copyright (c) 2022 Ángel Hernández https://creativecommons.org/licenses/by/4.0 2022-12-30 2022-12-30 99 4 163 183 10.51812/of.124715