Grey seals and harbour seals who live in the Wadden Sea are using social distancing to prevent virus infections from spreading among the group, scientists have found.

By taking aerial photographs the scientists could measure the distance the seals kept from each other while on the beach. The data showed that a harbour seal would keep an average of 1 metre and 66 centimetres away from its neighbour while grey seals would typically be at less than a metre’s distance.

The researchers think the difference in distance is due to a greater vulnerability to viruses in harbour seals.

Unlike the social distancing practised by people during the coronavirus crisis, the distancing in seals is probably an evolutionary response, researcher Jeroen Hoekendijk told local broadcaster NH Nieuws.

“Between 1988 and 2002, half of the harbour seal population died from the phocine distemper virus but hardly any deaths occurred among the grey seals,” Hoekendijk said.

“We had a hunch harbour seals kept their distance from their fellow seals but that they are actually socially distancing still came as a bit of a surprise,” he said.

The research was carried out by at the Royal Netherlands Institute for Sea Research (NIOZ), Wageningen University and the Swiss Federal Institute of Technology in Lausanne.