Migrating lovebirds who spend winter thousands of miles away from their mates have developed a knack of arriving at their breeding ground at the same time as their partners, researchers found.

Scientists at the University of East Anglia are astonished that Icelandic black-tailed godwits time their reunion with such accuracy despite spending winter alone and often on different continents.

However, if one partner turns up more than a few days late they are replaced by another bird who arrives on time.

Researchers who conducted the study already knew the birds usually mate for life and return to Iceland each year to breed. They assumed that paired birds stayed with each other during the winter.