The bikes, which can be found parked outside various places in and around the city, are activated via a smartphone app and costs 25 cents per 15 minutes to hire.
The bike-sharing company says on its website that its aim is to: "Provide affordable access to bicycles, solving the last kilometres of travel.''
After seeing the bike, Baker checked the company's app site - which shows where every available bike is at any given time - to see if it showed up.
"[I] found it showed on their app,'' she said.
"You need to zoom in a fair amount to spoke the bike.''
At the site this afternoon, a Herald photographer said tourists stopped to point and take photos.
Because of the heavy rain, the area was muddy and slippery and it would have taken a lot of effort to get the bike down there and get back up, the photographer said.
OnzO spokesman Min Kyu Jung said they had had to employ a team of field operators to go out to such incidents.
"Obviously we discourage people from leaving bikes where they shouldn't be.''
This is not the first time an OnzO bike has turned up in a peculiar spot; with bikes being hoisted up on trees and appearing on the app as being out on the water near the Viaduct.
At least one bike has also found its way on Trade Me; with one seller trying to make a profit until the sale was shut down.
Jung said it was expensive for the company; which was now hiring more field operators for this very reason.
In one incident, a field operator was called out to a report of a bike being locked up in a tree. They found that the tree had been secured heavily with ropes.
The company is now due to introduce new moves to limit people's ability to access the bikes because of such behaviour.
