A scientist who has just overseen a sprawling nationwide bird count is keen to find out exactly why a chilly early winter has brought more feathered visitors into our back gardens.
This year's week-long annual garden bird survey wraps up this the weekend, and organiser Dr Eric Spurr, of Landcare Research, said it was clear the colder weather had attracted a much higher number of birds to gardens than usual.
But why that was remained somewhat of a mystery, and more research was needed to establish the link, he said.
"I think what it implies is that food out in the wild is a bit limited, if you like, but our gardens are still a rich source of food."
NIWA figures showed that although temperatures were near average across much of the country in June, the mercury dropped sharply around the time the survey kicked off at the end of the month.