Seagulls pecking at leftover bratwurst rolls in downtown Nuremberg – this sight may surprise some people. Because most people associate seagulls with the sea. According to the umbrella association of German avifaunists, black-headed gulls are widespread in large parts of the Federal Republic. They also breed in colonies on the large lakes in southern Germany.
In winter they move to the cities. You can observe them particularly well in Nuremberg, Landshut or Munich. The biologist Stefan Böger from the government of Middle Franconia is interested in these observations, and he launched the “Participatory Seagulls” project together with his colleague Philipp Herrmann. This encourages people to observe black-headed gulls and report their location and, if possible, the number of the ring on their leg. “The aim of the project is to find out where the seagulls come from,” explained Böger. “This allows you to learn something about the migration routes.”
According to the project homepage, the black-headed gull (Chroicocephalus ridibundus) is the most common seagull in Germany and Europe. The chocolate-brown head and the call, which sounds like laughter, are typical. However, the birds change their plumage twice a year: in winter they wear a simple gray-white dress without any distinctive head coloring.
The black-headed gull was chosen for the project because it is easy to observe, said Böger. Nevertheless, it is still good for surprises: Initial results from the project indicate that the black-headed gulls in Nuremberg, for example, do not come from Lake Altmühl or other nearby ponds, but from Eastern Europe.
As winter tourists, they stay in the city when it is really cold, explained Böger. “At the Christmas market, for example, you will find a richly laid table.” In Landshut, on the other hand, primary schools are particularly popular, explains Herrmann. Secondary schools, on the other hand, are not as attractive because older children no longer drop as much lunch.
Around 400 seagulls regularly fly into Landshut during cold winters. So far there has been evidence of seagulls from the Czech Republic, Poland, Lithuania, Belarus, France, Belgium, Slovakia, Croatia and also from various parts of Germany, said Herrmann.
As soon as it gets warmer, the black-headed gulls leave the city again, said Böger. Where they then move is often unknown. According to Böger, more observations are necessary in order to gather better knowledge about black-headed gulls.