Swarm of bees streams past office buildings in Parnell, Auckland

Auckland office workers stopped and stared as a swarm of bees streamed past their window.

The insect horde began winging its way past an office building in Eglon St, Parnell, at about 8.45am today.

"My colleagues noticed it first," said Shirley Bisschoff.

"We have got these really big windows. We are on the first floor."

"There were thousands and thousands of bees. It took about 10 minutes for them to fly past, towards Fraser Park."

Bisschoff said no one had ventured out to see where the bees had settled.

"Safer inside," she said.

The bees swarmed along Eglon St, marked with the red pin, towards Fraser Park in Parnell, Auckland. Map / Google

Westmere beekeeper Chris Mellers said bees in New Zealand usually ceased swarming before the end of December each year, but this summer they were still doing it.

He said this might be because of warm, dry weather or the availability of flowers that bees liked.

"The floral abundance - it has been quite a good season in terms of flora. Pohutukawa has been going really well this year."

Beekeepers collect swarms.

Mellers said it was common for him to be called by people wanting a swarm removed from their property, "but at this time of year it's unusual".

"I've had a few calls in the last few days.

"I had one this morning but it was wasps. They don't swarm like bees. It's more 50 or 60 wasps rather than 50,000-plus bees."

He referred the person to a pest controller to deal with the wasps.

Mellers said swarming bees didn't usually sting people because they were "drunk" on honey.

The website beeswarm.co.nz, run by a group of beekeepers, says swarming occurs in spring and is a natural event in the life of a bee colony.

"It occurs when food sources are readily available and the bee numbers are rapidly increasing.

"Bees swarm to multiply the number of hives. A trigger for this is that the numbers in the hive increase and things get crowded.

"The hive is aware of the seasonal change and that spring is the best time to swarm, so a new hive has time to become established over spring and summer.

"Bees typically swarm in New Zealand between October and December."