The glowing waters around Auckland are a spectacular and elusive sight.
It's hard to believe the 'Aurora of the Sea' exists until you've viewed the blue lights of the phytoplankton, lapping on the shores after dark.
Fortunately a pair of photographers have made a guide to help you see the phenomenon in the waters around Tamaki Makaurau.
Grant Birley and Matthew Davison have been working for the past two years on a way to find the microscopic animals which cause the glow, after dark. While it's difficult to reliably do, they have some helpful pointers for phytoplankton hunters.
On Sunday night they used it to track down a display at Manly Bay, Northshore.
"We heard so many people say it's the first time they've seen it," said Grant.
While normally he says it is important to manage expectations and that displays are more vibrant through the use of photography, Sunday's show was particularly bright.
This was helped by bystanders who splashed about in the water, aiding the glow which is triggered by movement.
"When the next concentrated bloom heads our way, I hope to spot it and provide some advance warning and enable more people to witness the blue gold," Matthew writes.
NIWA reports into rising sea temperatures and phytoplankton have already mapped the phenomenon over prevailing temperatures, with Auckland and the Hauraki Gulf being a particular hot spot for sightings.
Although the phenomenon can be seen across the country.
"I've seen bio as far North as Cape Reinga and Tutukaka," says Grant.
Patience is key
The displays can be triggered at any time after dark, so patience and realistic expectations are vital.
"Unless you're very lucky the visual experience will be a lot more muted than a photographic one," he says.
The glow is the plankton's defence mechanism and will only be triggered by movement, so unless there is some current, fish or people in the water - you might never know it was there.
However even a dull flicker of light in the water tends to excite photographers and nature watchers, which is why Grant and Matthew began their guide to glowing waters.
"It's still very much in its infancy but a work in progress nonetheless"
Best glowing beaches in Auckland
Matakatia Bay
Tindalls Bay
Little Manly
Big Manly
Arkles Bay
Stanmore Bay
Red Beach
Mahurangi Regional Park
Muriwai
Piha
Anawhata Beach
Bethells
Te Arai
Manguwhai
Ruakaka
Oceans Beach
Matapouri
For more photos and tips on where to see phytoplankton visit @chasing_horizonz_ on instagram