Wellington mayor Andy Foster's chief of staff has resigned and will return to the Department of Conservation, the Herald understands.
Sarah Owen has been in the role for less than a year after starting the position in May.
She was previously the executive manager in former Christchurch mayor Sir Bob Parker's office, starting in that role a month before the February 2011 earthquake.
More recently, she was employed as systems design manager at the Department of Conservation, and as a private secretary in the Beehive working on conservation policy.
Owen's last day in the mayor's office will be April 23. She is taking a new job as chief sustainability adviser at the Department of Conservation.
Foster said in a statement that Owen's resignation was "obviously sad news" for him.
"But I recognise the fantastic opportunity that exists within her future role. One that will have national significance and speaks to her passion for the environment."
He said Owen came on board during the Covid-19 pandemic during challenging times for the city and New Zealand.
"She has worked tirelessly to establish a Mayor's Office that manages and engages with the diverse and complicated issues that face a capital city in an era of considerable challenges."
It has previously proven difficult to find staff for Foster's office.
In May last year the Herald reported it appeared the council was having a tough time finding someone to bridge the gap between Foster and the media, for example.
The council first advertised the role of public affairs adviser to the mayor in November 2019, although an experienced contractor filled the position in the meantime before joining the Ministry of Health as a senior adviser.
That role continued to be advertised on more than one occasion and recruitment agencies shoulder-tapped several individuals, only to draw a blank.
John Bullock was eventually hired as a media adviser and remains in the role.