engleski

Preliminary results of the first video-based ecological monitoring in the Croatian Natura 2000 coastal site

Legally prescribed ecological data monitoring has not been established at most of marine Natura 2000 areas in Croatia, and therefore legislation of ecosystems management and protection is not completely fulfilled. For the first time, to the best of our knowledge, a coastal time-lapse imaging survey has been carried out targeting the Šibenik coastal fish community (off Krka River, 5 m depth). Temperature and salinity data were collected concomitantly, both parameters being relevant to fish presence and abundance. One image per hour was collected during daytime continuously from January to March 2018, such collection is still being continued today. A total of 7 311 time-lapse images were analyzed for species classification and 288 Fish Forum Book of abstracts animal counting (epibenthic invertebrates included). Forty-one taxa were detected with fish prevalence, 70.73 percent of all recorded species. The rest being echinoderms (12.25 percent), cephalopods (7.3 percent), crustaceans (2.43 percent), anthozoans (2.43 percent), reptilians (2.43 percent) and birds (2.43 percent). Relevant observations were made of flagship species such as bluefin tuna, Thunnus thynnus (Linnaeus, 1758) and loggerhead sea turtle, Caretta caretta (Linnaeus, 1758). The latter was observed in both hibernation and swimming modes. Species richness, calculation of biodiversity, and degree of coverage of benthic invertebrates were also obtained as proof of concept of the validity of such coastal monitoring actions for large and growing EU infrastructural assets such as the Expandable Seafloor Observatory (OBSEA) and the European Multidisciplinary Seafloor and water column Observatory (EMSO) testing sites. Our data support the need for permanent video-based technical development of the European Strategy Forum on Research Infrastructures (ESFRI) to increment its social projection.

Natura 2000 ; monitoring ; underwater camera ; time-lapse ; Krka ; coastal fish community

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