A Bay of Islands conservation group is hoping the silence of the lockdown will allow urban tūī to match the more intricate songs of their forest cousins.
Brad Windust, of Bay Bush Action, said since the Covid-19 lockdown started, the group's trustees had noticed a dramatic increase in the number of people inquiring about the birds they were hearing and seeing.
They included rarely seen species such as the long-tailed cuckoo — which by now would normally be on their way back to their winter home in the Solomon Islands — and the "very shy" marshland-dwelling mioweka or banded rail.
People are also reporting lots of tomtits, riroriro (grey warblers), kūkupa (wood pigeons) and tūī.
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"We think it's not necessarily because there's more birds but because the big hum of the machine has come to a grinding halt," Windust said.
"There's just far less noise from industry, from boats, planes, cars and construction. Also, people have slowed down and are enjoying and observing nature more."
Windust's view is backed by experts who told the Advocate last week they were seeing far more birds than usual. They put it down to a combination of people having more free time and birds moving back into area vacated by humans during the lockdown.
Windust said the lockdown could have the added benefit of allowing tūī to rediscover their range of song.
A study by Massey University PhD student Sam Hill had found that urban tūī had more repetitive songs, sometime consisting of just one or two notes, than forest-dwelling birds.
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He suggested city tūī had developed louder, simpler calls so they could be heard by potential mates over man-made noise.
"Birds such as tūī may well be out practising their new tunes since lockdown," Windust
However, the group believed the bird benefiting the most from the absence of human noise was the kororā, or little blue penguin.
Sound carried much better underwater than in the air, making motor boats and jetskis deafeningly loud for nearby penguins.
"It's just another added stress for little blue penguins who have to constantly be aware of where boats are so they don't get hit," Windust said.
Although native birds appeared to be benefiting from the lockdown, they now also relied on humans for their survival.
Without pest control, many chicks were killed on the nest by predators such as stoats and rats, he said.