Biodiversity is declining across Europe. Modern agricultural practices, habitat fragmentation, la... more Biodiversity is declining across Europe. Modern agricultural practices, habitat fragmentation, land abandonment and climate change are key factors causing current trends in environmental change. Mobile organisms such as raptors, positioned high in the food chain, are good indicators of negative or positive landscape dynamics, since their response is fast. This assumption was tested by investigating the Scops Owl (Otus scops) population in a traditional Central European cultural landscape (Goričko Nature Park [GNP]) in Slovenia. The negative trend in male calling Scops Owls was correlated with static and dynamic environmental change variables derived from remotely sensed or field-based, multi-temporal data sources. Key geospatial predictors were identified and used for bird calling and breeding (C&B) suitability modelling. All geospatial models developed predicted a decline in C&B suitability (even by 33%) in almost all areas where the bird is currently active. However, the NE part of the GNP could achieve better C&B conditions for theScops Owl in the coming years (a potential 36% increase in suitability). Predictions indicate that more effort and action, to conserve the Scops Owl in the study area should be implemented in the N, NE and E part of the hilly GNP. Our results are thus highly applicable not just for decision makers in this protected area but rather in all areas across the Scops Owl's continental population, since the methodology is easily replicable and transferable.
Land consolidation can negatively affect biodiversity, as it is usually followed by the expansion... more Land consolidation can negatively affect biodiversity, as it is usually followed by the expansion of arable land, a decrease in crop and land cover diversity, and an increase in the application of agrochemicals. The aim of our study was to compare the species' composition and abundance of farmland birds, as well as habitat structure, on consolidated and non-consolidated sites in Goričko, NE Slovenia. Habitat diversity was much lower on consolidated sites compared to non-consolidated ones, with arable fields and associated habitats (e.g. grass field margins, field tracks) prevailing on the former. Non-consolidated sites held higher proportions of different types of meadows, hedgerows, solitary trees, succession and traditional orchards. Farmland bird diversity and the abundance of a majority of farmland bird species were higher on non-consolidated sites. The only two exceptions to this were the Eurasian Skylark and the Common Stonechat, which were more abundant on consolidated sites. Both of the species suffered population declines at Goričko in the period 1997-2016, bringing into question the suitability of intensively managed arable fields as their breeding and foraging habitat. Individual species' regression analysis revealed that the most influential positive explanatory variable for the presence of Redbacked Shrike, Tree Sparrow and Common Whitethroat was non-consolidated, extensively managed mosaic landscape, whereas for the Yellowhammer this explanatory variable was superseded only by forest islands without traditional orchards. Land consolidation, as performed in Slovenia, negatively affects farmland bird diversity and its European conservation value, which is why it should not be performed on Natura 2000 sites, designated for nature conservation.
We studied the effects of different land uses on conservation value and bird diversity in a North... more We studied the effects of different land uses on conservation value and bird diversity in a Northern Adriatic karstic landscape. Our research area was situated in SW Slovenia and was covered with dry pastures and meadows in different stages of forest sucession and with different grazing intensities. We surveyed birds in 2007 and 2012 using the line transect method, with 50.4 km being covered each year. In the analysis we divided the survey transects into 200 m tiles which were used as statistical units in the analysis. We then modelled conservation value, bird diversity and bird abundances with different land uses; we used boosted regression trees as a modelling tool. Canonical correspondence analysis showed that a distinct group of birds occurred on tiles with higher grazing intensity. The species in this group also had significantly higher abundances in 2012 than in 2007. Forest succession was the most important predictor of SPA conservation value (Special Protected Areas according to the Directive on the conservation of wild birds of the European Union) and had negative effect on it; grazing intensity had a unimodal positive influence on conservation value and was most beneficial at low intensity. The model for the European conservation value showed a rather low predictive power. Farmland bird diversity was also negatively affected by forest and positively by grazing intensity. For the four Natura 2000 species-protected species in the SPA Kras (Woodlark Lullula arborea, Red-backed Shrike Lanius collurio, Corn Bunting Emberiza calandra and Skylark Alauda arvensis), forest cover also had a negative effect. Grazing intensity had a positive effect for Woodlark, Red-backed Shrike and Skylark. The highest SPA conservation value and farmland bird diversity could therefore be achieved in a landscape with as low a forest succession as possible and grazing present but at low intensity. We recommend inclusion of Communicated by David Hawksworth.
Twenty years ago, the avifauna of Goričko was poorly known. The first systematic surveys at the e... more Twenty years ago, the avifauna of Goričko was poorly known. The first systematic surveys at the end of the 1990s yielded enough information to designate the site as an Important Bird Area (IBA). This book presents the results of the survey carried out in 2012 within the Upkač project (OP SI-HU 2007-2013), the results of tetrad surveys (2003-2010) and rare bird survey (2001-2014) from the database of the New Ornithological Atlas of Breeding Birds of Slovenia, the results of the common farmland bird survey and data from the monitoring of Natura 2000 Goričko site (2004-2013). The book discusses in detail the ecology of two breeders of traditional orchards, the Hoopoe Upupa epops and Scops Owl Otus scops. The mechanism of modern agriculture's influence on biodiversity is explained and nature conservation measures proposed to halt the population decline of farmland birds.
Due to numerous bird surveys in the past 20 years, the avifauna of Goričko is relatively well kno... more Due to numerous bird surveys in the past 20 years, the avifauna of Goričko is relatively well known. For some species, the very first national ecological researches were conducted in this area. The article summarizes all bird surveys so far. It presents population trends of farmland species which is one of the most threatened bird groups in Europe. Most of the qualifying species of this habitat that are protected within the Natura 2000 network have suffered a decline at Goričko, specifically Quail Coturnix coturnix, Scops Owl Otus scops, Hoopoe Upupa epops, Woodlark Lullula arborea and White Stork Ciconia ciconia. The number of breeding pairs of the latter has not changed, but its fecundity has decreased. Furthermore, populations of other farmland bird species have decreased, for example Skylark Alauda arvensis, Stonechat Saxicola rubicola, Serin Serinus serinus and Common Linnet Linaria cannabina, as well as butterfly populations and tracts of grassland habitat types. National agri...
Denac, K. (2015): Monitoring prepelice Coturnix coturnix na območju Krajinskega parka Goričko v letu 2015. Program finančnega mehanizma EGP 2009-2014, projekt Gorički travniki. DOPPS, Ljubljana
Denac, K. (2015): Monitoring smrdokavre Upupa epops na območju Krajinskega parka Goričko v letu 2015. Program finančnega mehanizma EGP 2009-2014, projekt Gorički travniki. DOPPS, Ljubljana
Denac, K., T. Mihelič, P. Kmecl, D. Denac, D. Bordjan, J. Figelj, L. Božič & T. Jančar (2015): Monitoring populacij izbranih vrst ptic - popisi gnezdilk 2015. Poročilo. Naročnik: Ministrstvo za kmetijstvo, gozdarstvo in prehrano. DOPPS, Ljubljana
BirdMap Data - GPS tracking of Storks, Cranes and birds of prey, breeding in Northern and Eastern Europe
NGO Kotkaklubi (Eagle Club) and 5D Vision Ltd have developed an online portal birdmap.5dvision.ee... more NGO Kotkaklubi (Eagle Club) and 5D Vision Ltd have developed an online portal birdmap.5dvision.ee, to visualize GPS data of migratory birds. Current dataset serves as a copy of source data for this visualization. The portal operates since 2006. Birds of 10 different species have been monitored, total number of individuals has been more than 120. Currently over 400 thousand occurrences (GPS fixes) are stored in the database. The data is managed via web-based backend that enables different methods of importing gps data (Movebank, manual upload for different receiver data formats). As the dataset covers long period of monitoring different species, various types of GPS transmitters have been used. Illustrated data about species and individuals can also be added. To enable publishing of the data to GBIF, synchronization to PlutoF biological data management platform was developed. The aim of the Birdmap portal is to increase awareness, international communication about nature and its prot...
The European population of Scops Owl Otus scops is estimated at approximately 83,000 pairs, with ... more The European population of Scops Owl Otus scops is estimated at approximately 83,000 pairs, with Spain and Croatia holding almost two thirds of all breeding pairs in Europe (Bavoux et al. 1997). In 1995, the number of breeding pairs in Slovenia was estimated at 500 – 800 (Geister 1995), or approximately 0.78% of the entire European population (Vrezec 2000). The greater part of its population in Slovenia breeds in Gori{ka and Primorska regions (SW Slovenia). The species can also be found in the regions of Gori~ko, [tajerska (Slovenske Gorice, Haloze, Kozjansko, Jovsi), Dolenjska (vicinity of Novo mesto and Ko~evje), Gorenjska (Bohinjska Bistrica, Kranj) and in the central part of Slovenia (Ljubljansko barje, Ljubljana; Geister 1995). Data on its population sizes is available only for a few areas within the country. In 1997, a large population of 210 calling males was discovered at Gori~ko ([tumberger 2000). In 1999, the number of breeding pairs in Kozjansko Regional Park was estimate...
Habitat Use of Eurasian Scops Owls Otus scops in an Agricultural Mosaic Landscape
Ardea, 2019
Farmland birds in the European Union have declined by 57% in the past 35 years, raising the need ... more Farmland birds in the European Union have declined by 57% in the past 35 years, raising the need for efficient, large-scale conservation measures to halt and reverse their negative trends. The Eurasian Scops Owl Otus scops is an indicator of extensively managed agricultural landscapes, typical of areas of high biodiversity. Its breeding biology is poorly known, but central to understanding the drivers of its marked decline in different European countries, including Slovenia. We used GPS-loggers to study home range size and habitat use of breeding individuals in NE Slovenia. Kernel home ranges (95%) of three females were estimated and their habitat use was analysed by spatial logistic regression models with Moran's Eigenvectors. Individual home range sizes ranged from 2.2 to 48.2 ha. In general, the females preferred to forage close to their nests. One female had a much larger home range than the other two, because of her exploitation of presumably highly profitable foraging grounds far away from her nest. In a mosaic of different agricultural habitats, the females showed a clear preference for extensively managed areas, such as hedges, meadows, abandoned vineyards and traditional orchards. Based on our findings several conservation measures are proposed, aimed at enhancing insect diversity and abundance as well as prey accessibility.
The paper summarizes current knowledge on the population size, habitat, conservation status and c... more The paper summarizes current knowledge on the population size, habitat, conservation status and conservation measures for the White-backed Woodpecker Dendrocopos leucotos in Slovenia. The species is an extremely rare forest specialist species. It inhabits mostly Dinaric beech Fagus sylvatica forests from Trnovski gozd, Nanos, Javorniki Mts and Mt Snežnik to the Kočevsko region and Gorjanci Mts. The species is also present in the Zasavje region and Mt Boč. The majority of the population (80%) inhabits the altitudinal belt between 700 and 1400 m a.s.l. The size of the Slovenian breeding population is currently estimated at 100-150 breeding pairs. Using the new survey playback method, we expect to find the species at additional sites. The highest densities were recorded on Mt Snežnik (0.7 breeding pairs/km2 in the Zatrep - Planinc forest reserve, 0.6 breeding pairs/km2 at Gomance) and in the Gorjanci Mts (0.6-0.9 breeding pairs/km2 in the Kobile forest reserve). The species inhabits be...
In 2014, 162 bird species were recorded during the bird ringing activities in Slovenia. Of 155 sp... more In 2014, 162 bird species were recorded during the bird ringing activities in Slovenia. Of 155 species, 62,275 birds were ringed, and 107 recoveries of birds ringed in Slovenia and found abroad, 148 foreign recoveries in Slovenia and 1395 local recoveries were recorded. The most frequently ringed species were Blackcap Sylvia atricapilla and Great Tit Parus major. As far as ringed nestlings are concerned, Great Tits and Barn Swalllows Hirundo rustica predominated. Considering the recoveries ringed of found birds abroad, the commonest were Black-headed Gulls Chroicocephalus ridibundus and Mute Swans Cygnus olor. The farthest recovery was a Barn Swallow Hirundo rustica found in the Democratic Republic of Congo (5171 km away). Among the more interesting finds was also the so far southernmost recovery of a Sand Martin Riparia riparia found in Israel. Let us also mention the first recovery of a Corncrake Crex crex, which bred and was ringed in 2013 at Planinsko polje (central Slovenia) an...
Survey of White-backed Woodpecker Dendrocopos leucotos on SPA Gluha loza in year 2014. Final report
In March and April 2014 a survey of White-backed Woodpecker was carried out at Natura 2000 site f... more In March and April 2014 a survey of White-backed Woodpecker was carried out at Natura 2000 site for birds (SPA) Gluha loza at Gorjanci. In total, 5-7 pairs were recorded, all in mature beech forests in Kobile valley with high amounts of dead and dying wood and a high percentage of large-sized trees. Outside this valley the White-backed Woodpecker was not discovered despite intensive search. We attribute this to poor condition of beech forests which are heavily logged. density in Kobile is among the highest so far recorded in Slovenia (0,6-0,9 pairs/km2). The current favourable status of the species in Kobile is a result of non-management. In the long term, this favourable status can only be maintained by excluding the forest from logging. According to our opinion, the following steps should be taken in order to ensure long-term conservation of the species: (1) declaration of the entire Kobile valley as forest and nature reserve, (2) inclusion of White-backed Woodpecker's ecologi...
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