The Lion Singer is one of the bird species that goes from Sweden to Africa before winter. Stock Photography.
Researchers at Lund University have investigated how small birds act when they are sick on their way to the winter in the south.
After two studies of migratory birds in Skåne Falsterbo, the researchers found that birds deal with diseases differently depending on their location and how strong their immune system is.
The birds have been vaccinated by researchers to get a feeling of fever and cold.
"Birds that are sick but who fly to Africa do not live as long as they go to southwestern Europe," said Arne Hegemann, a biologist and responsible researcher, to SVT Nyheter Skåne.
Birds infected with malaria have also been studied. Whatever the purpose, the birds continued their journey after several days of rest before they were fully recovered.
"The next step in this research is to see what happens when they leave Falsterbo, if sick birds arrive in the winter area or if they wake up," Arne Hegemann told SVT.