An influx of jail birds has forced Australian police to temporarily close a country police station and courthouse.

The problem has been caused by large numbers of wild pigeons nesting in the town of Murray Bridge, about 100 km east of the South Australian state capital of Adelaide.

"A consequence of the large number of pigeons are parasite infestations which are left through the pigeons nesting in the buildings and air conditioning," state police said in a statement on Wednesday.

The buildings will be fumigated and are expected to re-open by the weekend, but police said they would talk to local authorities to find a way to keep the pigeons out of jail.