1.Intermittent karst lakes are important for forming wetland habitats in otherwise dry karstic landscapes. With characteristic water regimes they are unable to retain water owing to their underground ...drainage system.
2.Many Dinaric intermittent karst lakes (karst poljes) have gone through severe human disturbances in the past, aimed at fluctuating water levels in karst poljes. These measures had the goal of achieving either permanent dry agricultural land or permanent lakes for various purposes. Usually dams were built for water storage to achieve these goals.
3.This research aimed to determine the population responses of bird species that are important for conservation, to water level changes on Cerknica Lake (Slovenia), a large Dinaric intermittent karst lake, to inform effective conservation for such systems.
4.Water level and vegetation were strong drivers of waterbird diversity and abundance, based on analysis using canonical correspondence analysis and boosted regression trees.
5.Water level was critical for the conservation of important bird species. Water and reed specialists (e.g. water rail Rallus aquaticus) require management of refugia in wetlands to create mosaics of water and reedbeds. The formation of nature reserves, quiet zones and habitat restoration is needed for these specialist species. In these areas, mowing should be limited or not present at all.
6.Measures dealing with land‐use change and connectivity between habitats, for instance agri‐environmental measures, are more appropriate for rare bird species with wider niche breadths (but still narrower than generalists), e.g. skylark (Alauda arvensis) and linnet (Linaria cannabina).
Several bird species utilize artificial structures for communal roosting. Between 26 May and 28 Jun 2012, the selection of buoys and times of departure by Mediterranean Shags Phalacrocorax ...aristotelis desmarestii were studied at three communal roosts within shellfish farms in the Bays of Sv. Jernej (Debeli rtic), Strunjan and Piran (Secovlje). A total of 3,110 buoys were counted and categorized into two groups according to their shape (horizontal and vertical) and colours. The black horizontally floating buoys were of two types (barrelshaped and oval). The Shags chose to utilize the horizontally floating buoys only, most often black and white in colour. Owing to their poorer stability and smaller standing surface, the vertically floating buoys are clearly unsuitable for them. The highest share of Shags with regard to the number of buoys of separate types was registered on black barrel-shaped buoys. As the percentage of occupied buoys was similar at all roost sites (36-39%), it was deduced that Shags distribute evenly among roosts, regardless of the number of individuals present in the Slovenian sea. At the larger roost at Debeli rtic, the percentage of adult individuals (73.5%) was greater than at Strunjan (42.5%). This could be due to the competition for better places, given that competitively stronger individuals select safer larger roosts. Between 5.42 and 9.00 hrs, 53.3% and 69.1% of Shags departed from the roost sites at Debeli rtic and Strunjan, respectively, with the majority of departures recorded between 7.50 and 8.30 hrs. They left their roosts mostly individually (48.7%) or in pairs (23.3%), at Debeli rtic predominantly in the SW (58.9%) and W (16.9%) directions, and at Strunjan in the NE (42.3%) and N (38.5%) directions.
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