Sebastian Menderski from the Polish Society for the Protection of Birds told PAP that birds started to nest on each artificial island.

"We are observing the largest movement on the island in Piecki, where there are more than 300 nests, including gull and tern nests. According to our observations, terns have also returned to Kwiecewo and Sątopy. We will know the exact number of nests soon, after we finish counting, but even without that we are very happy" - said Menderski in an interview with PAP and emphasised that success was all the greater because terns would not nests in Mazury for years, because they did not have appropriate conditions.

Tern nests on sandy islands, at their edges, where there is no high vegetation. For many years, birds had these ideal conditions on islands on Mazury lakes, because farmers were leaving cattle on the islands in the spring and taking it back in the autumn. Cattle fed on grass and created a perfect environment for the terns. Unfortunately, now the custom of carrying cows to the island has disappeared, and Mazury island have overgrown with forests. Therefore, ornithologists decided to build artificial islands for birds, for which they received EU support, since the cost of raising a single island would reach about PLN 200 thousand.

The project of ornithologists from Olsztyn was a novel idea, previously in Poland and in Europe floating islands were created for terns - rafts or floating platforms, recently even an old barge has been adapted for this purpose. Artificial islands for these birds have been built in the U.S., and the idea has proven successful.

Ornithologists from the Polish Society for the Protection of Birds have been monitoring river terns in Warmia and Mazury for three years. According to their observations before building the islands, these birds lived in the seven colonies, and their total number was estimated at 420-450 pairs.

River terns are a strictly protected species in Poland. (PAP)

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