- 1Institute of Oceanography and Fisheries, Šet. Ivana Meštrovića 63, 21000 Split, Croatia (dzoic@izor.hr)
- 2Croatian Meteorological and Hydrological Service, Ravnice 48, 10000 Zagreb, Croatia
The ichthyoplankton assemblage and its spatial distribution were studied in the eastern Adriatic Sea during two consecutive summers (2019–2020) using morphological identification, DNA barcoding and analysis of larval spatial dispersal. Ichthyoplankton samples were collected in five different areas: the western coast of Istria, Kvarner, the area along the outer coast of the island of Dugi otok, the Pomo Pit and southern Dalmatia. These locations were selected as starting points for the dispersion modelling.
The spatial distribution of ichthyoplankton was analyzed using a coupled modelling system that combined the hydrodynamic ROMS model with the individual-based Ichthyop model. The ROMS model was driven by surface momentum, heat and water fluxes calculated using output fields from the operational weather prediction ALADIN model as well as by Adriatic river inflows and tides. The open boundary conditions were obtained from the operational Mediterranean hydrodynamic model. The ROMS temperature, salinity and current fields were input for the Ichthyop model.
Connectivity matrices were calculated between the individual areas, focusing on local retention, i.e. the proportion of released ichthyoplankton that remained in its place of origin. Dispersal distances were determined by measuring the distance between the initial location where the ichthyoplankton was released and its final location after drift, taking into account environmental factors such as currents. In addition to the influence of ocean currents, environmental factors such as temperature, salinity and chlorophyll-a (Chl-a) concentration played an important role in shaping the composition of ichthyoplankton, as shown by the RDA analysis, which revealed that early life stages of the fish families Sparidae and Serranidae were associated with higher sea temperatures, while those of Scombridae, Engraulidae, and Bothidae were linked to elevated Chl-a levels.
The obtained results provide important basic data for the sustainable management and conservation of the Adriatic ichthyoplankton and its habitats.
How to cite: Džoić, T., Beg Paklar, G., Zorica, B., and Stanešić, A.: Ichthyoplankton dispersion modelling in the Eastern Adriatic During Two Consecutive Summers (2019–2020), EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17343, https://doi.org/10.5194/egusphere-egu25-17343, 2025.
