According to this story from The Press (30 May 2007). The Coastguard is struggling to find $17 million to pay for 25 life-saving boats to such an extent it is slashing its own administration.
As with the volunteer fire service and ambulance New Zealanders lives depend on charity rather than Government spending. The Coastguard operates 75 boats on no more than $5 million a year - not counting of course the volunteered time of the crews. For Government $17 million is not a lot of money but for a struggling charity it is a fortune to raise.
The current defence force does provide some degree of coastguard support work. Without the Orions search capability long distance rescues would be impossible. The Navy also has four coastal patrol vessels and 8 NH-90 helicopters on order than could contribute to emergencies if they are needed. But while the Navy can assist with search and rescue it is not part of its core mission which is to defend New Zealand's sealanes.
The whole point of the reorganised force proposed on my website is to bring more civilian duties into the role of the military. Thus the force proposed on the website includes four inshore surveillance aircraft(DHC-6 Twin Otter), four EH-101 response SAR helicopters, and four inshore patrol vessels. These are located in Auckland, the Chathams, Nelson and Invercargill.
This is not to mention a training EH101 plus eight A109M ambulance helicopters and three Falcon &x MPA aircraft based at Ohakea.
While this is not the same as the Coastguard's fleet of smaller vessels it should be pointed out that at 160 knots the EH101 helicopters in Nelson could attend life-threatening situations 40 nautical miles off the coast of Kaikoura just as quickly as a 30-knot coastguard boat based in Kaikoura could - and do so regardless of sea-state. The only problem with a single resource is if there are multiple rescues.
This is not to say that the Coastguard should not continue as a voluntary organisation, just that it should be the first line of security for New Zealand mariners not the only line of defence.