The celebration of World Environment Day in Krka National Park

The celebration of World Environment Day in Krka National Park
The Minister of Environmental Protection and Green Transition Marija Vučković and her colleagues visited the Krka National Park on the occasion of World Environment Day

This year's World Environment Day, which is celebrated under the slogan “Our Land. Our Future. We are #Generation Restoration”, is aimed at habitat restoration projects, a key pillar of the UN's Decade of Ecosystem Restoration (2021-2030).

Habitat restoration projects are a focus of the Krka National Park. The LIFE project to remove the invasive species of tree-of-heaven (Ailanthus altissima), the management of macrovegetation, and the selective fishing of invasive species of pike, are all projects that have resulted in the activation of old water courses, the return of species that had not been recorded in this area for one hundred and thirty years, and the restoration of the fish stock, showing the importance of long-term sustainable management of habitats and management decisions made in order to protect and restore the environment.

"The Krka National Park is an excellent example of an institution that has implemented a program to combat certain invasive species in accordance with the Strategy and Action Plan for the Protection of Nature of the Republic of Croatia for the period from 2017 to 2025, the fundamental document for the protection of nature, which determines long-term conservation goals and sets guidelines for the preservation of biodiversity and geodiversity and the manner of its implementation. One of the special goals of the Strategy is the establishment of a management system for non-native species and the implementation of measures to prevent the introduction and spread of invasive alien species, and their suppression", stated the Minister of Environmental Protection and Green Transition, Marija Vučković and added: "Data collection and database maintenance, as well as education and raising public awareness, are important segments of invasive alien species management. Climate change further promotes the spread of invasive species, and in the future, increasing pressure from these species on native habitats and species is expected, so projects like this are extremely important for their restoration and protection."

In order to preserve habitats and autochthonous plant species and to prevent the spread of tree-of-heaven, an invasive foreign species, the Krka National Park is participating as a partner in the "LIFE CONTRA Ailanthus" project of the above ministry. On the occasion of the World Environment Day, examples of trees-of-heaven were removed from a plateau at the Skradinski buk waterfall.

"The project is planned to establish control over the invasive species tree-of-heaven in the Mediterranean region of Croatia. The project is being implemented at eight locations in the Krka National Park. As part of the field activities, in addition to the removal of the invasive plants, experts collect and analyze data and assess the impact of the project on various habitats, pollinators, and soil biodiversity, while last year they were joined by volunteers. The main expected results of the 'LIFE CONTRA Ailanthus' project are the improvement in the conservation status of Natura 2000 habitat types, the preservation of the cultural heritage, the prevention of the further spread of invasive non-native species, but also the very important development of a national protocol," said Gordana Goreta, expert advisor at the Krka National Park.

Even before entering into this project, the Krka National Park carried out activities to remove the tree-of-heaven species from test plots in the Park. After their removal, old streams were reactivated, where parallel monitoring continued of travertine growth, the dynamics of the formation of new plant and animal communities necessary for this growth, and the physical-chemical parameters of the water.

"In addition to the activation of former water courses, in the Krka National Park we have noted another important indicator of habitat regeneration as a direct result of management decisions. Trentepohlia aurea, the only terrestrial alga, was recorded again along the Krka River after one hundred and thirty years. This algae was recorded in the first scientific investigations of algae back in 1890, and it was found again only now on blocks of old travertine at the Skradinski buk waterfall, next to the place where swimming was permitted between the end of the waterfall and the wooden pedestrian bridge. The specific conditions necessary for the growth and development of this terrestrial algae and its sensitivity to human activities make it a special biological phenomenon, which, after more than a century, is again being researched," stated the director of the Krka National Park, Nella Slavica, and added: "This is a shining example of the importance of habitat regeneration, which confirms how important it is to persist in management decisions aimed at protecting and restoring the environment, especially when it comes to travertine, our unique habitat type, which is also included in the European Habitats Directive."

The 2020 Regulations for the Protection and Preservation of the Krka National Park restricted swimming at the Skradinski buk waterfall. This measure led to the restoration of plant and animal life and the revival of tufa formation, the fundamental phenomenon of the Park.

The removal of pike from the Krka River, which is not its natural habitat, is also a long-term process in the fight against invasive species, on which the Krka National Park is intensively working. A project is being implemented to monitor the state of non-native and invasive species in the Krka River, and in cooperation with the Institute for the Protection of the Environment and Nature, a pilot project for the removal of invasive species from the Krka River was adopted, with an emphasis on pike. The local population is exceptionally allowed to catch pike along the entire Krka River. On this occasion, Minister Vučković presented the most successful pike fishermen with packages of fishing equipment. In cooperation with the Faculty of Natural Sciences and Mathematics of the University of Zagreb, an action plan for the further fishing of invasive species and the possibility of reintroducing native species is being developed, and a new LIFE project is being prepared "The improved state of conservation of target freshwater species and habitats in the regions of the Natura 2000 ecological network".