Trevor, who didn't have his phone with him to capture the moment, enjoyed watching the interactions for about 10 minutes before the white tui flew off with some of the others into the distance.
Each day Trevor walked through the garden, hoping to see the white tui again, before seeing it in similar circumstances two weeks later.
This time he had his phone with him and got some amateurish snaps of the white tui that proved to family and friends "that I was not seeing things".
There were a few more sightings before spring was gone and so was the white tui.
Trevor did some research with Birdsnz and discovered it had been a leucistic tui, which wasn't considered rare or reportable.
And that the whiteness was because of a genetic abnormality possibly caused through inbreeding.
He felt a bit deflated with that information, but it was fleeting because being in the white tui's presence had been special and had left him with "a spiritual feeling of wonder".
Fast forward a year to this spring and Trevor hoped to see the white tui again.
His hope turned to reality when the kowhai trees burst into flower in September and the white tui reappeared.
He was thrilled it had survived the winter, was still in the area, and hadn't been a victim of predation because it stood out from others.
Trevor took an avid interest in the tuis, especially those inhabiting a large kowhai tree.
"It was noticeable that one tui would become the dominant tui and take command of the tree, chasing away any other bird that turned up.
"During the first weekend in October, the white tui staged a coup and took over the role as the dominant tui of the kowhai tree.
"We watched fascinated for the next three days as the white tui fended off all comers, keeping command of the tree.
"Any bird that tried to settle on any branch was at once chased off.
White tui enjoying some nectar and keeping guard. Photo / Emmet Riddle
"Not only tuis, the vanquished included fantails, blackbirds, thrushes, bellbirds, rosellas, sparrows, waxeyes, a multitude of finches, grey warblers and even kereru.
"The white tui was seldom away from the tree for longer than a few minutes at a time during the day.
"At dusk it left, presumably for its nest, then returned at dawn each morning for another round."
One day Trevor's son Emmet, who is a photographer, arrived home, and with a Sony A6600 and an 18-105mm lens, took some quality photos of the white tui.
"I was surprised how the bird wasn't too bothered with me getting up close to it," Emmet said.
"I managed to get a few decent shots of the tui in focus and was absolutely stoked with what I captured.
"I posted one photo of the white tui on social media and was really surprised at the amount of interest it received, with people commenting things like a once-in-a-lifetime sighting and how lucky I was to photograph the rare bird.
"It's pretty amazing to see what my parents have created during their time living in Te Horo with such beautiful gardens, trees and a pond which has been a welcome spot for all sorts of birdlife."
One afternoon the white tui left the garden and has not returned, especially as the kowhai flowers had finished their bloom and were waning.
But the garden's flaxes are producing their flower spikes and the bloom normally creates another influx of tuis.
Trevor said, "I am hopeful the white one will reappear to dazzle us once again."
