Tens of thousands of swallows died in South Africa a week before they were due to migrate to Europe, BirdLife South Africa said on Wednesday, blaming unusually cold March weather. ( dpa )
A sudden cold snap coming from in Angola gripped South Africa's northern lowveld (savannah) towards the end of the southern summer in mid-March.
"Due to this the birds could not feed properly as it was too wet and too rainy for them to acquire the food. They became hypothermic and hypoglycaemic," BirdLife director Gerhard Verdoorn was quoted by SAPA news agency as saying.
"The tens of thousands of birds were falling down everywhere and just dying," he said, adding residents in Limpopo province had at first suspected poisoning.
The birds were supposed to migrate on March 23, the day of the equinox. Some birds survived and started their migration on March 28, he said.
"Over the past couple of years it has become a more frequent occurrence and it is not only the swallows that are been affected but several other species of birds."