The breeding biology of the Dalmatian Pelican Pelecanus crispus, a vulnerable bird species in the Palaearctic, has been studied for 7 years at Lake Mikri Prespa, a continental wetland and Tsoukalio lagoon, a coastal wetland within the Amvrakikos Gulf. The two colonies showed stability, with fluctuations in the number of breeding attempts each year varying by about 30% over a period of 7 years. The date of arrival at the breeding sites and the date of laying of the first egg varied between mid‐February and mid‐March. The egglaying period (including renesting) varied between 18 and 114 days between years. The annual average clutch size varied between 1.60 and 1.94 eggs per nest. The incubation period averaged 31.4 ± 1.4 days. The overall hatching success varied from 36% to 70%. Egg losses were mainly due to nest abandonment, infertile eggs and eggs rolled from the nests. The Dalmatian Pelican chicks took 11–12 weeks to fledge. Nestling mortality was very low in contrast to other species of pelican. Such a low nestling mortality explains why the breeding success each year is largely explained by the hatching success.
The Dalmatian pelican (DP) Pelecanus crispu s and the great white pelican (GWP) Pelecanus onocrotalus are listed as 'Vulnerable' and 'Least Concern', respectively, in the IUCN Red List. We present an updated estimation of the Black Sea / Mediterranean flyway population status of both species, based on data provided by experts working in all 7 countries of the region where pelicans breed and/or overwinter, who came together at the 1st Workshop on Pelican Research and Conservation in Prespa, Greece. The DP breeding population in the Black Sea and Mediterranean countries increased from 1730−2105 pairs in the years 2000−2010 to 2154−2437 pairs in 2011−2012. Approximately 40% of the Palaearctic breeding population of GWP occurred in Southeast Europe and Turkey. In 2011−2012 the GWP population in this region was estimated to be 4702−5175 pairs, and has remained more or less stable during the last decade. Although all the breeding sites for both species are in protected areas, disturbance at nesting places was considered to be the main threat. Direct persecution and electric power lines still cause occasional problems. In deltaic lagoons, erosion and inundation of nesting sites cause breeding failures in DPs, while in inland wetlands large water level fluctuations are a widespread problem. Decrease of fish stocks is a threat, especially in coastal areas. Many stop-over wetlands along GWP migration routes between Southeast Europe and Africa have been seriously degraded or have disappeared, resulting in serious implications for their populations. Conservation needs are listed, but further research is recommended for both species.
Spatial synchrony in population dynamics has been documented recently across a range of taxa, and a number of hypotheses about the mechanisms driving spatial synchrony and the consequences of this phenomenon for the persistence of populations have emerged. Spatial environmental covariance is one of the principal factors influencing this synchrony on a large scale. However, most studies focus on population abundances, and little evidence exists on the spatial synchrony of demographic parameters. We used a 15-year dataset from two populations of a vulnerable bird species, the Dalmatian Pelican (Pelecanus crispus), to identify local and global environmental factors that cause population synchrony. We show that survival rates were temporally synchronised between the studied populations and that a large part ([50 % for both populations) of this covariation was driven by local environmental conditions. Several components of the North Atlantic Oscillation index were correlated with local climatic conditions, but not all of these components can be used as informative proxies for future variation in survival. We also present evidence that an individual's future survival can be strongly influenced by the conditions occurring during the early period of its life. Environmental factors such as water level and food availability had similar influences on breeding success and juvenile survival. Juvenile survival was lower during dry years and years of low food availability. This finding indicated that intraspecific competition may act as a limiting factor for species demography, especially in large populations. Estimating the strength of synchrony is important and should be considered in population and metapopulation analyses and in relationship to conservation measures.
δυνητικών τόπων διατροφής βάσει των μετακινήσεων και της κατεύθυνσης των πτήσεων 4.3.2.4. Λ ί μνη Καστορ ι ας 86 4.3.2.5. Λίμνες Χειμάδι τη και Ζάζαρη 89 4.3.2.6. Βρωμολίμνη -Μεγάλη Πρέσπα 4.3.3. Χρονοδιάγραμμα χρήσεως των τόπων διατροφής στη δ ι άρκε ι α της αναπαραγωγ ι κής περ ι όδου 93 5. ΣΥΖΗΤΗΣΗ 5.1. Β ι ολογ ί α αναπαραγωγής 97 5.1.1. Αφ ι ξη στην απο ι κ ί α αναπαραγωγής 97 5.1.2. Κατανομή των αναπαραγωγικών υπομονάδων στο χώρο κα ι το χρόνο Χ 5.1.3. Διαστάσεις αυγών και διάρκεια ωοτοκιών 5.1.4. Επωαστική περίοδος 5.1.5. Επιτυχία εκκόλαψης και παράγοντες που επηρέασαν τη θνησιμότητα των αυγών 5.1.6. Αναπαραγωγική επιτυχία και παράγοντες που επηρέασαν τη θνησιμότητα των νεοσσώνXI
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