Invasive species

The presence of non-native species that compete, displace or prey on native ones is a serious conservation problem in island environments. The Galician Atlantic Islands National Park is taking actions on this front.

There is a plan to control the American mink and the domestic cat, which are a serious threat to seabirds, one of the most important assets of the Park.

As for the invasive terrestrial flora, the maximum effort was directed to the cat's claw, black acacia, eucalyptus, arum lily, African daisy and stinking everlasting. Other species such as the St. Augustine grass, the vinca, the false acacia, the New Zealand spinach, the cassava and the black nightshade were also subject to control. Very different working protocols were established from those carried out so far for controlling the arum lily and the cat's claw, achieving highly satisfactory results and substantial economic savings.

In the marine environment, the action was focussed on the invasive algae Sargassum muticum.

RECOVERY OF INDIGENOUS ISLAND ECOSYSTEMS IN THE PARK

Actions carried out so far were aimed at restoring the indigenous island ecosystems of the Galician Atlantic Islands National Park by eliminating invasive alien species that negatively affect conservation of habitats and autochthonous populations of wild species, and alter the rich biodiversity of flora and fauna.

Invasive alien species are the second factor that cause the greatest impact on biodiversity loss and reduction of natural ecosystem supply services. These introduced species displace native species, which in space-time fulfil the different balanced ecosystem functions. These functions include soil retention, protection of the water regime, intervention in pollination, formation of natural ecosystems in this geography together with other species, and all of the above shapes our landscape, as we know it today.

The lack of control of these invasive alien species led to an imbalance in ecosystems due to the loss of natural control of pathogenic species, and affected other native species leading to their displacement or choking, causing a loss of species diversity in vascular plants, fungi, lichens, invertebrates, amphibians, reptiles, birds and mammals. Therefore, the prevention and control of invasive alien species must be carried out in accordance with EU mandates.

The National Park's terrestrial island ecosystem and some of its peculiar environmental characteristics gave rise to a differentiated flora and fauna scenario that we must protect. Human action on island systems, especially in the last 300 years, negatively affected the islands' biodiversity components. This caused remarkable disruptive action due to the direct or indirect introduction of exotic species that managed to establish and expand with the consequent transformation in the different islands worldwide, as well as in the islands that make up the National Park.

Even though the species census in Galicia is not yet complete and final, the estimate is that there are more than 10,000 species present in the marine and terrestrial environments, of which around 450 have legal protection status derived from European, state and regional regulations. The number of species protected in the Galician Atlantic Islands Marine-Terrestrial National Park is 191, and corresponds to 12 plants and algae, 16 invertebrates, 7 fish, 3 amphibians, 13 reptiles, 123 birds and 17 mammals.

A rational and effective response to this serious environmental problem will not be possible without a joint response from the Administration and society.