1,721,108 research outputs found
Does the Ural owl Strix uralensis breed at Ljubljansko barje?
No full textDuring the winter 1993/94 the author observed, in the so-called Kozlerjeva gošča forest reserve at Ljubljansko barje (Ljubljana Marshes), a pair of Ural Owls Strix uralensis macroura. From December to March, 8 records were made. The owls frequented the forest edge, and it was only once that the female was seen flying to the maize field nearby. Although the time of observor the assumption that the owl bred in the forest reserve, the author states three reasons which do not speak in favour of such possibility: 1) Utterly non-breeding disposition of the observed Ural Owls (winter vagrancy), 2) The forest reserve is too small to be a suitable breeding habitat for this bird, 3) Human disturbance. To the Ural Owl observed at Ljubljansko barje the authorattributes the status of a periodic visitor
Evaluation of the response of forest birds to the vocalization of the Eurasian Pygmy Owl (Glaucidium passerinum) as an indication of predator presence
Full text linkV naravi se ptice na svojega plenilca malega skovika (Glaucidium passerinum) burno odzovejo z agresivnim vedenjem, čemur pravimo mobing. Želeli smo ugotoviti, kakšna je specifičnost intenzitete odziva gozdnih ptic na oglašanje malega skovika glede na območja z in brez prisotnosti malega skovika, katere ptice se odzivajo in v kakšnem številu ter kakšne so sezonske spremembe odziva ptic. Poleg tega smo želeli oceniti še zanesljivost ocenjevanja prisotnosti malega skovika z beleženjem odziva ptic. Terensko delo smo opravili na Jelovici, kjer je mali skovik prisoten, in v gozdu pri Brniku, ki je bilo kontrolno območje brez malega skovika. Na več točkah smo v jutranjem času predvajali posnetek oglašanja malega skovika in beležili odziv ptic. Ugotovili smo, da je odziv vrstno in krajevno specifičen, saj se ptice odzivajo le na plenilca, ki ga poznajo (v tem primeru malega skovika) in le na območju, kjer je le-ta prisoten. Večinoma se odzivajo vrste, ki predstavljajo potencialen plen malega skovika, poleg odraslih osebkov so v mobing vključeni tudi mladi osebki. Jeseni je bil odziv ptic intenzivnejši, saj je bila številčnosti ptic, ki so se odzvale precej večja kot spomladi. Zaradi specifičnosti bi odziv ptic lahko uporabljali za ugotavljanje prisotnosti oziroma odsotnosti malega skovika na določenem območju.In the wild, small birds respond to their predator, the Eurasian Pygmy Owl Glaucidium passerinum, with aggressive behaviour, i.e. mobbing. We aimed to determine the specificity of response rate of the forest birds to the broadcast vocalization of the Eurasian Pygmy Owl comparing between areas with and without the owl presence. We compared species structure of mobbing birds taking into account their numbers and seasonal changes in the response rate. In addition, we wanted to assess the reliability of estimating the presence of the Eurasian Pygmy Owl by recording the response of mobbing birds. Filedwork was carried out at Mt. Jelovica, where the Eurasian Pygmy Owl is present, and in the lowland forest near Brnik, which was the control area without the owl. We broadcast the playback of the Eurasian Pygmy Owl male song on multiple sites in the area in the morning and observed the response of the birds. We found that mobbing response is species-specific and locally specific, since birds responded only in the areas with the Eurasian Pygmy Owl being present. Mostly the species that represent the potential prey of the owl responded, in addition to adult specimens, young specimens are also involved in mobbing. In autumn, the response of birds was more intensive, with the birds responding in much higher numbers than in spring. Because of the specificity, the mobbing response of the birds could be used as a reliable indication of the presence of the Eurasian Pygmy Owl in a particular area
Some interesting details from the life of tawny owl Strix aluco
No full textThe author presents his observations and a thorough study of the Tawny Owl Strix aluco in the village of Hrastje near Polčane from 1991 to the beginning of 1994. The observations were made possible with the aid of the owl\u27s recorded songs or calls broadcast there, for with such method the presence andnumber of owls can be quickly ascertained in a certain area. In this way a Tawny Owl male, among other birds, was provoked which, however, reacted ratheraggressively to the recorded song. In May 1991 the author discovered a Tawny Owl\u27s nest in a beech hole, but unfortunately it went to ruin due to a sudden and considerable fall in temperature at that time. In the following years, however, the Tawny Owl bred there successfully In 1992, 4 chicks were fledgedthrough the entire summer they kept together, but in late autumn theysuddenly scattered to the four winds. The author describes the bird\u27s three dif ferent daily resting places: nest hole, man made hatchery, and chimney on the roof in the vicinity of the owl\u27s nest hole. Most interesting was certainly the latter, for the owl was not no ticed there by other birds and thus remained undisturbed. The test, according to which the owl\u27s song wasbroadcast in the immediate neighbourhood of the above mentioned house was interesting as well. There were a number of different birds attracted by it, but did not dis turb the owl perching on top of the chimney The studied owl was a grey variety of this species. In this region it hunts also in different sheds, stables and stalls, where it catches according to the author\u27s belief -mostly dorm ice Glis glis, black rats Rattus rattus and house mice Mus usculus, which together with other small mammals hunted in nearby forests any vineyards represent the greater part of its die in this area.Avtor opisuje triletno opazovanje in preučevanje lesne sove Strix aluco v vasiHrastje pri Poljčanah od leta 1991 do začetka leta 1994. Avtor predstavi opazovanje sov s pomočjo predvajanja posnetka sovjega petja. S takšno metodo opazovanja je mogoče hitro ugotoviti prisotnost in številčnost sov v nekem območju. Tako je avtor izzval samca lesne sove, ki pa se je ob predvajanju posnetka vedel precej agresivno. Maja 1991 je pisec odkril leglo v duplu bukve, ki pa je zaradi podhladitve istega leta žal propadlo. Toda v naslednjihletih je tu sova še uspešno gnezdila. Leta 1992 so bili speljani štirje mladičivse poletje so bili skupaj, jeseni in pozimi pa so se razkropili. Pisec omenja tri različna dnevna počivališča lesne sove: gnezditveno duplo, umetno valilnico in dimnik na strehi hiše blizu gnezditvenega drevesa. Najzanimivejše je prav slednje, saj ptiči sove na dimniku niso opazili in je niso napadali. Zanimiv je bil tudi poizkus, ki ga je avtor izvedel s predvajanjem sovjega oglašanja v neposredni bližini omenjene hiše. Ptiči so sicer prileteli, vendar sove na dimniku niso vznemirjali. Opazovana sova je bila siva različica lesne sove. Lesna sova na tern območju pleni tudi v različnih lopah, hlevih itd., kjer lovi po avtorjevem mnenju predvsem polhe Glis glis, črne podgane Rattus rattus in hišne miši Musmusculus, ki skupaj z drugimi malimi sesalci, ki jih sova pleni v gozdu in vinogradih, sestavljajo glavnino prehrane na tem območju
Influences of interspecific relations on spatial distribution between forest birds of prey and owls
Full text linkResponse of wild birds to feeding of brown bear, wolf and white pelican in ZOO Ljubljana
Full text linkŽivali v ZOO Ljubljana hranijo po določenem urniku s specifično hrano glede na posamezno vrsto živali. Gre za stalen in relativno dostopen vir hrane, ki ga izkoriščajo nekatere prostoživeče ptice. To predstavlja tudi izgubo hrane za oskrbovane živali. V raziskavi smo popisali prostoživeče vrste ptic na območju živalskega vrta ter ugotavljali, katere od njih se hranijo s hrano namenjeno rjavemu medvedu (Ursus arctos), volku (Canis lupus) in rožnatemu pelikanu (Pelecanus onocrotalus). Med aprilom 2015 in januarjem 2016 smo na območju izvedi tri popise ptic. Hranjenje medvedov in volkov smo snemali s kamero in analizirali prisotnost prostoživečih ptic in njihovo vedenje. S poskusom smo ocenili, koliko mesa lahko vrana med hranjenjem poje. Med hranjenjem pelikanov smo popisali število prisotnih sivih čapelj in njihovo vedenje. Z opazovanjem smo določili število osebkov na krmišču in njihov odziv na hrano (kaj in koliko so jedli). Poskušali smo ovrednotiti škodo, ki jo ptice povzročijo živalskemu vrtu. Pri hranjenju opazovanih živali so se pojavljale v glavnem siva vrana, sraka in siva čaplja. Med hranjenjem medvedov so se vrane hranile z briketi, ribjimi glavami in ribami. Med vranami je bilo malo kompeticij, medvedu pa so se izogibale. Med hranjenjem volkov so vrane s kljuvanjem pojedle približno 1,9 % govejega mesa namenjenega volku v poletnem in 3,2 % v zimskem obdobju. V to oceno ni zajeta količina kunčjega mesa, ki so jo odnesle, ki pa je verjetno višja. Domnevamo, da so vrane tudi koristne, saj med brskanjem po tleh pojedo tudi ostanke, ki bi sicer verjetno gnili. Med hranjenjem pelikanov je bila prisotna samo siva čaplja, ki je pojedla 1,7 % rib namenjenih pelikanom.Animals in Ljubljana ZOO are fed with a specific diet to a set schedule. This represents a consistent and relatively accessible food source for some species of wild birds. Consequently there is a loss of food for kept animals. This thesis intends to survey wild birds foraging on feeding grounds of brown bear (Ursus arctos), wolf (Canis lupus) and white pelican (Pelecanus onocrotalus) and survey the size of populations living in ZOO area. Between April 2015 and January 2016 we carried out three surveys of bird populations. Feeding of bear and wolf had been filmed and presence of wild birds, along with their behavior, was monitored. We conducted an experiment to determine the average amount of meat that hooded crow can consume when feeding. During feeding of pelican we documented the number of grey herons and their behavior. By observation, we determined number of specimens in the feeding area and response to food (the type and quantity of consumed food). An attempt was made to evaluate the loss to the ZOO caused by birds. During feeding of observed animals, mainly hooded crow, magpie and grey heron were spotted. During feeding of bear, hooded crows consumed a kibble, fish and fish heads. There was little conflict among crows, but they avoided the bear. During feeding of wolf, hooded crows consumed approximately 1,9 % of meat by pecking in summer observation period and 3,2 % in winter observation period. However, they managed to carry away a significant amount of rabbit carrion that was not included in this estimate. We suspect the presence of crows has also some benefits, since they feed on leftover pieces of food that would otherwise be left to rot. During feeding of pelican, only grey heron was observed. It consumed only 1,7 % of fish dedicated to pelicans
Spatial distribution of the avian predators of small mammals in the Ljubljansko barje in the non-breeding season
Full text linkDispersion and microhabitat selection of Morimus funereus
No full textSaproksilne vrste žuželk so zaradi intenzivnih gozdarskih praks vse bolj ogrožene. Bukov kozliček (Morimus funereus), kot varstveno pomembna in karizmatična neleteča saproksilna vrsta hrošča, predstavlja dober modelni organizem za preučevanje disperzije slabo mobilnih saproksilnih vrst. Prav tako je za učinkovito varovanje njega in njegovega habitata, od katerega so odvisne tudi številne druge saproksilne vrste, potrebno podrobno poznavanje biologije vrste. Z metodo sledenja z radijskimi oddajniki smo želeli ugotoviti disperzijske zmožnosti bukovega kozlička, vpliv temperature in relativne vlažnosti zraka na njegovo aktivnost in preference do hranilnih rastlin. Bukov kozliček je pokazal nižjo disperzijsko zmožnost od letečih saproksilnih vrst, zato je pomembno, da za namene ohranjanja vrste varujemo večje sklenjene gozdove. Pri nizkih temperaturah je bila mobilnost osebkov izrazito nizka, pri višjih temperaturah pa so bile samice bolj mobilne od samcev. Osebki so se zbirali na in v bližini sveže posekanega lesa, zato je metoda monitoringa bukovega kozlička s štetjem in lovom osebkov na enotah svežega lesa bolj primerna od metode štetja osebkov vzdolž transekta. Skladovnice hlodovine populacijam bukovega kozlička predstavljajo pomembno potencialno grožnjo. Osebki so se najpogosteje zbirali na svežem lesu jelke (Abies alba), ki je bila na območju tudi najbolj razpoložljiva. Pri prehranjevanju so pokazali preferenco do listavcev. Bukov kozliček je bil z metodo spremljanja z radijskimi oddajniki preučevan prvič.Saproxylic species of insects are increasingly threatened by intensive forestry practices. Longhorn beetle Morimus funereus is a charismatic flightless saproxylic beetle of conservation importance and as such represents a good model species for studying the dispersion of poorly mobile saproxylic species. Detailed knowledge of the species biology is crucial for the purposes of protecting M. funereus, as well as its habitat and other species that inhabit it. Beetles were tracked with radio transmitters in order to determine the dispersal capabilities of the species, effects of air temperature and relative air humidity on its activity and its preference for host plants. Compared to flying saproxylic species, M. funereus has shown low dispersal capabilities, therefore conservation of large forests is needed for its protection. The mobility of M. funereus was markedly low at low temperatures, whereas at higher temperatures females were more mobile than males. Specimens accumulated on and near freshly cut wood, therefore the method of counting and trapping specimens on units of dead wood is a more appropriate for population monitoring than transect counts. Timber piles represent an important potential threat for the populations of M. funereus. Individials were most commonly found on fresh wood of silver fir (Abies alba), which was also the most available at the study site. For feeding, M. funereus has shown a prefrence for deciduous species. This was the first study of M. funereus by means of radio tracking
Comparison of biodiversity of selected animal groups on breeding territories of tawny and ural owl
Full text linkPreferred body temperature ranges comparison between common wall lizard (Podarcis muralis) and horvath\u27s rock lizard (Iberolacerta horvathi)
Full text linkMorphometry and locomotor performance of the common wall lizard (Podarcis muralis) from natural and urban habitat
Full text linkPozidna kuščarica (Podarcis muralis) naseljuje raznolika življenjska okolja. V različnih okoljih lahko kuščarice razvijejo prilagoditve na lokalno okolje. V naši raziskavi smo primerjali pozidne kuščarice iz naravnega in urbanega okolja. Okolji sta se med seboj razlikovali predvsem po količini in gostoti vegetacije ter naklonu podlage. Opisali smo morfometrične lastnosti in gibalne sposobnosti obeh spolov kuščaric iz obeh okolij in ugotavljali, ali med njimi obstajajo razlike. Na kuščaricah smo izmerili šest morfometričnih meritev in v laboratorijskem poskusu izmerili največjo hitrost teka po ravnem in navkreber. Predvidevali smo, da bodo imele kuščarice iz naravnega okolja, kjer je vegetacija redka in naklon podlage bolj strm, daljše okončine in bodo dosegale večje največje hitrosti kot kuščarice iz urbanega okolja, kjer je vegetacija gostejša, podlaga pa večinoma horizontalna. Nasprotno smo ugotovili, da imajo kuščarice iz urbanega okolja značilno daljše zadnje okončine in dosegajo večje največje hitrosti pri teku po ravnem in navkreber kot kuščarice iz naravnega okolja. Med spoloma smo ugotovili razlike: samci so imeli značilno daljše zadnje okončine in večje glave, samo pri kuščaricah iz naravnega okolja pa smo opazili tudi, da imajo samice značilno daljše trupe kot samci.Common wall lizard (Podarcis muralis) inhabits diverse habitats. In different habitats they can develop adaptations to local environment. In the study we compared lizards from natural and urban habitat, which had different coverage and density of vegetation and different inclination of ground.
We described morphometric characteristics and locomotor performance for both sexes from both habitats and found out weather there are differences among them. We measured six morphometric parameters and in laboratory experiment we have measured the fastest sprint speed on horizontal and vertical surface.We assumed that lizards from natural habitat, where vegetation is scarce and ground is steeper will have longer limbs and will perform faster maximum speed than lizards from urban habitat where vegetation is more dense and ground mostly flat. On the contrary, we have found that urban lizards had longer hind limbs and acquire higher maximum sprint speed on flat and sloped surface than lizards from natural habitat. We have also found that there were differencies between sexes with males having longer hind libms and bigger heads. Only in lizards from natural habitat, females also had longer trunks than males
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