Unique North American bird may have nested in Sweden

A ring-billed gull native to North America may have bred with a herring gull in Sweden.

For the first time ever in Sweden, a ring-billed gull has nested, and this time with a common herring gull, says ornithologist Andréas Forsman to the radio.

According to Forsman, there is much evidence that the ring-billed gull has nested, as it behaves like a parent.

But since a third bird has been seen at the nest, a DNA analysis will determine the chicks' origins.

The chicks are out practicing their flight. It's very spectacular to study them in this way, says Forsman.

He points out that a ring-billed gull has only been documented breeding in Europe once before. That was in Northern Ireland in 2004.

Last year and earlier this year, the American gull was seen in Stockholm.