A combination of factors have combined to create a shortage in military personnel. 

In the 21 months to April this year, the New Zealand Defence Force lost almost a third of uniformed staff.  

It leaves gaps which mean three Navy patrol vessels and the Navy's main transport vessel can't be at sea because of safety issues.  

Auckland University Associate Professor of International Relations Stephen Hoadley told Tim Dower that this has been building gradually as the tempo of exercises has increased. 

He says then came Covid, which reduced training time and meant upgrading that should have happened, didn't. 

Hoadley says pay disparities between the public and private sector also play into it. 

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