CuriousCity: The many duties of Wellington's maritime police
When the call comes in, the Lady Elizabeth IV is out on the water within 15 minutes - but sea rescues are not the only task Wellington's maritime police are called upon to perform.
Whether it's patrolling marine reserves, helping Customs inspect foreign vessels, intercepting immigrants as they swim for shore, or responding to burglaries at beach-side batches, there is plenty to keep the 12-man police maritime unit busy.
Lady Elizabeth IV skipper, Senior Sergeant Dave Houston, has been part of the unit for 20 years. His relationship with the "Lady Liz" began as many others do — with a rescue.
"It was a windsurfing race, from Eastbourne to Petone, and a whole stack of us got all becalmed in the middle of the harbour," he said.
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Houston had been a beat cop for six years and was sold on the Lady Elizabeth IV instantly.
When at home, the Lady Liz can be seen patrolling during big sporting events and fireworks displays, or zipping around the Wellington Harbour at high speed.
The quick pace is not a sign of the crew having fun — 30 knots (55kmh) is the ship's cruising speed.
"That's the most efficient speed ... we are actually saving the taxpayers money," Houston said.
Common duties include handing out speeding tickets to boaties and jet-skiers, as well as the occasional rescue of a swimmer or kayaker.
It was a slightly unusual rescue in the harbour that Houston recalled as one of his favourite days on the job.
"We had a dolphin that was swimming around ... with a fish net embedded into its tail."
When none of the boats could capture the dolphin, Houston jumped in.
"The dolphin was going around and around in circles. He could see me and he was getting closer and closer, and it was like her knew that I was trying to help him or her.
"Eventually the dolphin swam right up to me and I was able to chop the fishing net off his tail," he said.
The Lady Elizabeth IV is a vessel packed with hi-tech gadgets, including infrared and night vision cameras.
It also has a computer that combines wind speeds, tides, and recent sightings to predict the location of a missing swimmer.
Operating as a mobile command centre, the Lady Elizabeth IV regularly has six radios in action at once.
Through these, her crew can organise other vessels to ensure a search area is swept as quickly as possible, with minimal overlap.
Every member of the crew is a sworn police officer, meaning they are trained for the same situations any land-based officer might face.
For this reason, the ship's sick bay comes complete with a hand cuffing point.
Despite popular presumption, the Lady Elizabeth is not named after any monarch.
It actually gets its name from the grandmother of the original Marlborough Sounds-based builder, Fred Musgrove, who had the boat requisitioned by the Government during the Second World War for police duty.
The original boat is long gone, and the impressive silver catamaran Wellingtonians have seen for the past seven years is in fact the fourth.
Three crew have died in the past, two when the Lady Elizabeth II capsized during a training exercise in 1986, while another was swept overboard during a rescue in 1978.
Last year, the Lady Elizabeth IV was absent from Wellington for 35 days. During these trips the launch travelled as far as Kaikoura, Farewell Spit and Nelson.
Facilities include a toilet, shower, kitchenette, and sleeping areas for up to 10 crew.