Mapping of Coastal and Benthic Marine Habitats in the Coastal Sea of the Republic of Croatia and Benthic Marine Habitats in the Croatian Epicontinental Belt

Project name: Mapping of Coastal and Benthic Marine Habitats in the Coastal Sea of the Republic of Croatia and Benthic Marine Habitats in the Croatian Epicontinental Belt

Client: Ministry of Economy and Sustainable Development
Period: 09/2021 – 10/2023
Location: Croatia


The main objective of the project entitled “Mapping of Coastal and Benthic Marine Habitats in the Coastal Sea of the Republic of Croatia and Benthic Marine Habitats in the Croatian Epicontinental Belt” is to map coastal and benthic marine habitats within the national territory of the Adriatic Sea, which includes the coastal areas and the areas of the Exclusive Economic Zone (continental shelf). The aim is to produce a comprehensive map of marine habitats in order to improve the availability of data on marine biodiversity, including the distribution of species and habitats.

In line with the Habitats Directive and the Marine Strategy Framework Directive, systematic mapping of coastal and benthic marine habitats will improve our understanding of the distribution and status of marine resources. This includes supplementing data within the Nature Protection Information System (including a spatial database on habitats), monitoring the state of species and habitats, and establishing conservation objectives for the Natura 2000 ecological network in the sea. Furthermore, it will aid in the better development of Natura 2000 and protected areas management measures, evaluation of suitability for the ecological network, marine resource management and planning, spatial planning in marine areas, and contribute to the organization and implementation of scientific research of the sea and reporting according to international obligations.

During the project implementation, mapping activities were carried out to create a map of coastal and benthic marine habitats in the coastal sea of the Republic of Croatia and Exclusive Economic Zone.

Prior to mapping, comprehensive planning was conducted, including the development of a detailed mapping plan, general guidelines, and field protocols for mapping, along with a revision of the existing National Marine Habitat Classification (mNKS). The detailed mapping covered the following areas:

  • coastal and benthic marine habitats up to a depth of 5-10 metres,
  • benthic marine habitats in the coastal sea up to 40 metres deep,
  • benthic marine habitats in the ecological network area up to 100 metres deep,
  • benthic marine habitats in protected areas up to 200 metres deep,
  • benthic marine habitats in isolated areas, ranging from 40 to 100 metres deep,
  • benthic marine habitats of a total of 300 km2 in two separate zones of the Exclusive Economic Zone.

Mapping of marine habitats in areas lacking detailed mapping utilized modeling techniques, followed by data validation, unification, and analysis. This effort resulted in the creation of a spatial database covering 51% of the marine area of the Republic of Croatia. Acoustic methods, along with satellite and aerial remote sensing, were employed in conjunction with field in-situ data collected from over 4000 transects (including dropdown camera, ROV, diving, and granulometry).

The coastal and benthic marine habitat mapping encompassed the coastal sea, territorial sea, and Exclusive Economic Zone. The total area of the map is 30,278 km2. Detailed mapping accounted for 6,661 km2, while the remaining 23,617 km2 was generated through habitat map modeling.

The project has provided guidelines for further product sustainability and has prepared a maintenance plan, as well as a final report with guidelines for further activities of use, dissemination, and maintenance, i.e., base upgrades. A revision of the National Marine Habitat Classification (mNKS) was also undertaken.

Various methodologies and data collection techniques were applied in the project, involving a significant human resource commitment (over 200 members) and equipment deployment (including 5 ships and numerous cameras for recording and other equipment). The detailed mapping phase consumed over 5400 man-days (23 working years), while over 15,000 man-days were allocated to data processing and validation, all aimed at creating a comprehensive map of marine habitats.

The results of the project are publicly available in the form of a database on the GIS WEB portal of the Croatian Ministry of Economy and Sustainable Development (MINGOR).

The project falls under the responsibility of the Ministry of Economy and Sustainable Development and is implemented by a consortium including OIKON Ltd., Institute of Oceanography and Fisheries, Croatian Geological Survey, Faculty of Geodesy of the University of Zagreb, and the Ruđer Bošković Institute. Subcontractors on the project were the Croatian Hydrographic Institute, ECOTECH d.o.o., SCIOM d.o.o., and DVOKUT – ECRO d.o.o.. Oikon’s share in the project was 24.4%.

OIKON Ltd. – Institute of Applied Ecology’s activities within the project included:

  • mapping of coastal habitat types using remote sensing and in-situ field methods,
  • mapping of marine habitats up to the 5th level of the national classification of marine habitats using direct in-situ mapping methods, including the use of drop-down cameras,
  • mapping of benthic habitat types (up to the 5th level of the national classification of marine habitats) based on the extent of visibility using satellite imagery and aerial photogrammetry,
  • integration of mapping data generated through remote sensing and acoustic mapping methods into a comprehensive map of marine habitats,
  • cartographic generalization and the creation of a map of marine habitats, along with an accompanying spatial database,
  • topological quality control of the produced map.
Oikon d.o.o.
Oikon d.o.o.