Beekeepers in the North Island are scratching their heads - and ducking for cover - due to the exceptionally high rate of swarming going on.
Swarming is one of the ways bees reproduce - with the queen bee leaving the hive - along with about half of the bees to establish a new colony, before a new queen bee emerges in the hive.
Plant & Food Research bee scientist Mark Goodwin said swarms were annoying for beekeepers as they lost half their bees and honey production dropped but the environmental conditions this year had been perfect for it.
"Some years we get virtually no swarms and years like this year, we get very large numbers of swarms," Dr Goodwin said.
"The thing that stimulates it is just getting a light nectar flow, just at the right period in the spring, and that encourages the bees to thing 'well spring's here, it's time to reproduce'.
"If that nectar flow is delayed then they quite often won't swarm or, if it's a very heavy nectar flow, they won't swarm either."
The hives on Plant & Food Research's Ruakura campus had produced 10 -15 swarms in a two-day period, Dr Goodwin said.