The breeding population of Spoonbill Platalea leucorodia in Croatia, estimated at 154-275 breeding pairs, is classified as Endangered. The main reason for the unfavourable status is loss of ...breeding/feeding habitats. The purpose of the study was to detect changes in the habitat types previously assessed as important for Spoonbill's feeding. The study area was chosen for two reasons: (1) the alluvial wetlands of the central part of the Sava River hold the biggest colony of Spoonbills in Croatia, and (2) availability of data on feeding ecology of Spoonbills along alluvial wetlands of the Sava River. We used the MODIS (Moderate Resolution Imaging Spectroradiometer) Enhanced Vegetation Index (EVI) as the main indicator for the changes in habitat structure along critical habitats for Spoonbills. The analysis identified areas with significant changes in EVI for habitat types important for feeding of the Spoonbills during the 2000-2008 period. Pastures, especially those with high wetness potential, changed in significant percentage despite conservation efforts in this habitat type. Changes in EVI were detected on ca. 9% of the pastures. For that reason we urge for better monitoring of the Spoonbill's feeding habitats 'in situ' and more specified characterisation of the reasons for the detected changes.
U posljednjih dvadesetak godina sve više radova dokumentira utjecaj klimatskih promjena kako na pojedine vrste tako i na cijele ekosustave. U ovome radu dati su rezultati dugogodišnjeg uzorkovanja ...dimenzija jaja (duljina, širina i volumen) populacije poljskog vrapca u odnosu na srednje proljetne temperature (ožujak–travanj) i srednju količinu padalina (ožujak–travanj) tijekom 36–godišnjeg razdoblja. Općenito, o utjecaju okolišnih čimbenika na dimenzije jaja ima malo objavljenih radova. Uzorkovanja u ovome radu obavljena su na području sela Mokrice (sjeverozapadna Hrvatska) u razdoblju od 1980. do 2015. godine. Proljetne su temperature u prosjeku značajno porasle u istraživanom razdoblju
dok u padalina nije bilo promjena. Međutim, nije došlo do odgovora na porast srednje proljetne temperature (ožujak–travanj) u istraživane populacije u smislu povećanja ili smanjenja dimenzija jaja. Rezultati istraživanja u ovom području demografije ptica su
oskudni i u nekim slučajevima kontradiktorni. Neki autori govore o povećanju prosječne veličine jaja, dok drugi govore o smanjenju veličine jaja u nekih vrsta ptica kao odgovor na porast temperature. Očito, veličina jaja u ptica složeno je pitanje budući da je tu uključeno
i niz drugih čimbenika osim sve toplijih proljeća, primjerice stanje ženke, genetička komponenta, obilježja staništa itd.
Veličina jaja koje ptica treba snesti jedan je od prvih „problema“ svake ženke tijekom reprodukcijskog ciklusa. Ovo istraživanje trebalo je dati odgovor na teoretsku pretpostavku prema kojoj bi u ...gnijezdima s porastom broja jaja trebao padati volumen (ili masa) jaja. Međutim, u ovom istraživanju rezultati su suprotni, povećanjem broja jaja raste volumen jaja u svrake Pica pica. To je zabilježeno i kod neki drugih ptičjih vrsta. Tumači se „dobrim godinama“ i/ili „dobrim stanjem“ ženke u razdoblju gniježđenja. Zaključno, rezultati
istraživanja svrake na području sjeverozapadne Hrvatske ne podržavaju „hipotezu ustupka“ (inverzije između veličine jaja i veličine pologa).
In this study, some key aspects of the breeding performance of the pied wagtail are reported for the first time in northwestern Croatian. Only first clutches are included. The average egg length was ...20.04 mm, breadth = 14.96 mm, volume = 2276.41 mm³ and egg shape index = 1.34. Egg dimensions and shape index did not vary significantly among the years in the study period (2006 to 2008). Egg size differences of the pied wagtail in different clutch size classes were also not significant. Egg length and egg breadth had the significant positive correlation. Average full clutch size for three years combined was 5.29, ranged from four to six eggs and modal clutch size was five (63.1 %). There was no significant difference in clutch size across the three years. We did not find any evidence for negative or positive relationships between clutch size and egg size in the researched bird species.
Na području Mokrica (Hrvatsko zagorje) je u razdoblju od 1980. do 2013. godine praćena proljetna selidba čvorka. Statistička je analiza pokazala da nije bilo ranijeg povratka čvoraka sa zimovanja u ...spomenutom razdoblju. Također, srednja mjesečna temperatura
mjeseca veljače i ožujka nije se značajno promijenila od 1980. do 2013. godine. Prosječna temperatura na globalnoj je razini porasla u posljednjih stotinjak godina te su mnogi organizmi, pa tako i ptice, odgovorili na te promjene svojim životnim ciklusima. Mnoge se ptičje vrste vraćaju ranije sa zimovanja, neke su počele ranije s polaganjem jaja, jedne nesu veći broj jaja, druge nesu veća jaja, treće pomiču areal rasprostranjenja itd. Do sada je najviše radova objavljeno iz područja fenologije. Stupanj fenoloških promjena
varira između vrsta, između lokaliteta, ali i unutar iste vrste različitih lokaliteta. Nužna su daljnja istraživanja i traženja još mnogih odgovora na klimatske promjene za razne životne cikluse ptica budući da je ornitofauna važna sastavnica mnogih ekosustava, a
ptice imaju i značajnu ulogu bioindikatora.
The breeding population of Spoonbill Platalea leucorodia in Croatia, estimated at 154-275 breeding pairs, is classified as Endangered. The main reason for the unfavourable status is loss of ...breeding/feeding habitats. The purpose of the study was to detect changes in the habitat types previously assessed as important for Spoonbill’s feeding. The study area was chosen for two reasons: (1) the alluvial wetlands of the central part of the Sava River hold the biggest colony of Spoonbills in Croatia, and (2) availability of data on feeding ecology of Spoonbills along alluvial wetlands of the Sava River. We used the MODIS (Moderate Resolution Imaging Spectroradiometer) Enhanced Vegetation Index (EVI) as the main indicator for the changes in habitat structure along critical habitats for Spoonbills. The analysis identified areas with significant changes in EVI for habitat types important for feeding of the Spoonbills during the 2000-2008 period. Pastures, especially those with high wetness potential, changed in significant percentage despite conservation efforts in this habitat type. Changes in EVI were detected on ca. 9% of the pastures. For that reason we urge for better monitoring of the Spoonbill’s feeding habitats “in situ” and more specified characterisation of the reasons for the detected changes.
An assessment of DNA integrity in erythrocytes using the alkaline comet assay was carried out to estimate the impacts of water pollution on Balkan loaches (Cobitis elongata Heckel et Kner, 1858) ...inhabiting the Sava and Kupa Rivers, rivers of varying different water quality. The amount of DNA damage in cells was estimated from three different parameters: comet tail length as the extent of genetic material migration, tail intensity (% DNA in comet tail) and tail moment. The results suggest a genotoxicity of the aquatic environment in the Sava River and demonstrated significantly lower levels of DNA damage in fish captured from the Kupa River. This study confirmed that the comet assay, applied to fish erythrocytes, is a useful tool in determining potential genotoxicity of water pollutants. Although a good DNA damage pattern for Balkan loach was obtained, due to its global and regional conservation status, only restricted use of a small number of specimens per sampling site could be permitted. PUBLICATION ABSTRACT
A new spined loach species Cobitis jadovaensis is described from the Jadova River in Croatia. This species differs from its congeners in the Croatian Adriatic basin with a unique set of characters: a ...very short dorsal fin base; short anal fin base; narrow head; a single lamina circularis; a single small prominent dark inclined spot on the upper part of the caudal base; all four Gambetta zones well developed and reaching beyond the dorsal base; zones Z1 and Z3 with many irregular spots; zone Z1 narrower than Z2; zone Z2 as wide as Z3; zone Z2 with spots larger than a pupil size fuses with Z3 on caudal peduncle; zone Z4 wider than Z2 and Z3, with 11 - 14 roundish to oval blotches. PUBLICATION ABSTRACT
Izloženi su rezultati opažanja u dolasku lastavica (Hirundo rustica) sa zimovanja iz Afrike južno od Sahare na područje gniježđenja u selo Mokrice (sjeverozapadna Hrvatska, Hrvatsko zagorje) u ...razdoblju od 1980. do 2011. godine. Iako su zabilježene stalne fluktuacije u datumu proljetnog dolaska, utvrđeno je da nije došlo do promjena u trendu vremena dolaska. Oscilacije temperature proljetnih mjeseci (ožujak–travanj) u najbližoj meterološkoj postaji ukazuju na trend porasta prosječne temperature za otprilike 2,2 °C u istom razdoblju.
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