Najbli\u017ei srodnik mu je rod Necturus<\/em> iz Sjeverne Amerike, \u0161to nam govori da je \u010dovje\u010dja ribica prisutna na ovom podru\u010dju vi\u0161e od dvjesto milijuna godina. Ta nevjerojatna vrsta svjedo\u010dila je nastanku i nestanku dinosaura.<\/p>\n Pra\u0107enje stanja populacije \u010dovje\u010dje ribice Proteus anguinus<\/em> provodi se metodom linijskog transekta za vrijeme niskog vodostaja, odnosno slabog protoka vode, i optimalne vidljivosti. Istra\u017eiva\u010d, speleoronilac, roni po prethodno definiranoj transektnoj liniji poznate duljine i broji sve jedinke koje vidi ispred sebe i one lijevo i desno od sebe, a podaci se zatim obra\u0111uju u programu DISTANCE 8.0. Analizom podataka dobiva se apsolutna procjena populacije, odnosno broja odraslih jedinki \u010dovje\u010dje ribice po \u010detvornom metru. Kona\u010dni rezultat izra\u010dunava se kao relativna veli\u010dina populacije odraslih, spolno zrelih jedinki za cijeli lokalitet (poznati dio \u0161pilje). Ta metoda dovoljna je za takav tip monitoringa, kojemu je cilj primarno pratiti trend populacije kroz dulje razdoblje.<\/p>\n \u010covje\u010dja ribica ciljna je vrsta podru\u010dja ekolo\u0161ke mre\u017ee Natura 2000 \u0160ire podru\u010dje NP \u201eKrka\u201c (HR2000918). Na podru\u010dju NP \u201eKrka\u201c prisutna je u \u0161piljama na podru\u010dju Miljacka slapa: Miljacki II, Miljacki III, Miljacki IV i Sustavu Miljacka I \u2013 V te u Jami nasuprot Torka na u\u0161\u0107u \u010cikole u Krku. Sustavno pra\u0107enje populacije \u010dovje\u010dje ribice od 2017. godine provodi se u \u0161pilji Miljacka II i Sustavu Miljacka I \u2013 V (prethodno od 2012. godine kroz projekt Proteus), od 2019. godine u \u0161pilji Miljacka III, a ove godine stanje populacije prvi je put pra\u0107eno u \u0161pilji Miljacka IV.<\/p>\n Pra\u0107enje du\u017e definiranih transekata u \u0161piljama na podru\u010dju Miljacka slapa obavljeno je u kolovozu i studenome 2022. godine. Primjerci \u010dovje\u010dje ribice, adultni i subadultni, evidentirani su u svim \u0161piljama. Procijenjena populacija u Sustavu Miljacka I \u2013 V je dvanaest jedinki na 3 600 m2<\/sup>, slijede populacije iz \u0161pilje Miljacka II i Miljacka III s po pet jedinki na 3 600 m2<\/sup>. Procijenjen broj od osamnaest jedinki na 3 600 m2<\/sup> u \u0161pilji Miljacka IV rezultat je malog broja evidentiranih jedinki i malog broja ponavljanja transekata, na \u0161to nam ukazuju granice procjene (velika nepreciznost), pa za taj lokalitet, da bi se dobila preciznija procjena, treba pove\u0107ati napor, odnosno populaciju treba pratiti najmanje dvaput godi\u0161nje.<\/p>\n Analizom populacije obavljenom na temelju podataka dobivenih tijekom pet godina njezina pra\u0107enja u Sustavu Miljacka I \u2013 V i \u0161pilji Miljacka II utvr\u0111en je negativan trend, ali ne i direktni uzroci njezine ugro\u017eenosti. S obzirom da je populacija \u010dovje\u010dje ribice prisutna u gotovo svim dijelovima speleolo\u0161kih objekata, te su oscilacije mogu\u0107e i zbog kretanja jedinki unutar sustava ovisno o vodostaju i dostupnosti hrane. Za \u0161pilje Miljacka III i Miljacka IV broj jedinki i broj pra\u0107enja nije bio dostatan za procjenu trenda. Prema prvim podatcima, izgledno je da je populacija u \u0161pilji Miljacka III sli\u010dnija onoj iz Sustava Miljacka I \u2013 V.<\/p>\n Iako je podru\u010dje NP \u201eKrka\u201c sigurno uto\u010di\u0161te za tu vrstu, voda koja protje\u010de tim podzemnim sustavom mo\u017ee donijeti \u0161tetne tvari koje mogu imati negativan utjecaj na \u010dovje\u010dju ribicu i ostalu \u0161piljsku faunu. S ciljem otkrivanja uzroka toga negativnog trenda provest \u0107e se daljnja istra\u017eivanja i nastaviti pratiti stanje kako bismo pravovremeno reagirali i o\u010duvali stani\u0161ne uvjete i stabilnost populacije \u010dovje\u010dje ribice.<\/p>\n Foto: Petra Kova\u010d Konrad, Du\u0161an Jeli\u0107<\/p>\n <\/p>\n [\/hr]<\/p>\n [en] Its nearest relative is the genus Necturus<\/em> from North America, indicating that the olm has been present in this area for more than 200 million years. This incredible species witnessed both the rise and fall of the dinosaurs.<\/p>\n Monitoring the population of the olm, Proteus anguinus,<\/em> is conducted using the linear transect method during periods of low water levels, when flow is weak and visibility is optimal. The researcher, a cave diver, dives along a previously defined transect line of known length, and counts all the individuals they see underneath and to the left and right of the line. These data are then analysed in the program DISTANCE 8.0 to give an absolute assessment of the population, i.e., the number of adult individuals of olm per square metre. The final result is calculated as the relative size of the adult population and sexually mature individuals for the entire locality (known part of the cave). This method is sufficient for this type of monitoring, in which the primary aim is to track population trends over longer periods of time.<\/p>\n The olm is a target species of the NATURA 2000 ecological network, Krka National Park area (HR2000918). In the part area, this species is present in caves in the Miljacka slap waterfall area: Miljacka II, Miljacka III, Miljacka IV and the system Miljacka I-V, and in the Nasuprot Torku pit (pit opposite of Torak) at the mouth of the \u010cikola into the Krka. Systematic monitoring of the olm population has been ongoing in the Miljacka II cave and cave system Miljacka I-V since 2017 (previously from 2012 through the Proteus project), since 2019 in the cave Miljacka III, and started for the first time this year in the cave Miljacka IV. Monitoring along the defined transect in the caves in the Miljacka slap waterfall areas was conducted during August and November 2022. Specimens of olm, both adult and subadult, were recorded in all caves. The estimated population in the cave system Miljacka I-V is 12 individuals\/3600 m2<\/sup>, followed by the populations in the caves Miljacka II and Miljacka III, each with 5 individuals\/3600 m2<\/sup>. The estimated population size of 18 individuals\/3600m2<\/sup> in the cave Miljacka IV is the result of the small number of recorded individuals and the small number of repeated transects, indicating the assessment limits (and low precision), and therefore for a more precise assessment of this locality, greater efforts are required with a minimum of two monitoring sessions each year.<\/p>\n An analysis of the population trend over a five-year period in the cave system Miljacka I-V and the cave Miljacka II indicated a negative trend, even though no direct causes of threat were identified. Since the olm population is present within all parts of the cave, these oscillations are also possible due to the movement of individuals within the cave system due to water levels and food accessibility. For the caves Miljacka III and Miljacka IV, the number of individuals and number of monitoring sessions was not sufficient to assess trends. Based on the initial data, it appears that the population in the cave Miljacka III is similar to that in the cave system Miljacka I-V. The area of Krka National Park provides a safe haven for this species, however, the water flowing through these underground systems can potentially carry harmful compounds that could have a negative impact on the olm and other cave fauna.<\/p>\n With the aim of finding the potential cause for the observed negative trend, further research and monitoring will be conducted in order to ensure a timely response, and to preserve the habitat conditions and population stability of the olm.<\/p>\n Photo: Petra Kova\u010d Konrad, Du\u0161an Jeli\u0107<\/p>\n <\/p> The olm is the only true stygobiont vertebrate in Europe, and the species is specific because it is the only living representative of the genus Proteus.<\/p>","protected":false},"author":1,"featured_media":6095,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[45],"tags":[],"class_list":["post-9404","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-monitoring"],"_links":{"self":[{"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/posts\/9404","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/comments?post=9404"}],"version-history":[{"count":4,"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/posts\/9404\/revisions"}],"predecessor-version":[{"id":14041,"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/posts\/9404\/revisions\/14041"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/media\/6095"}],"wp:attachment":[{"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/media?parent=9404"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/categories?post=9404"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/npkrka.hr\/en_us\/wp-json\/wp\/v2\/tags?post=9404"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![](\"https:\/\/npkrka.hr\/wp-content\/uploads\/covjecja-ribica-1.jpg\")
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<\/div>
\nMonitoring the olm population in Krka NP<\/strong>
\nThe olm is the only true stygobiont vertebrate in Europe, and the species is specific because it is the only living representative of the genus Proteus<\/em>. <\/strong><\/p>\n<\/div>
\n[\/en]<\/p>\n","protected":false},"excerpt":{"rendered":"