“It’s the ones who have never been found that play on my mind,” Spencer said.

“Their families are left without answers and without a body to mourn. It’s incredibly difficult.”

Spencer said he came up with the idea in 2023 when he read an article about shrinking Southern Alps glaciers.

“That kind of flicked a switch in my head. As the ice melts, human remains and property could be uncovered. If that happens, how will we start our investigation to know who it belongs to?”

Police said there have been times when human remains have been found with no clear way to identify them.

For example, it took five years to identify climber Terry Jordan’s property and remains, found on the lower reaches of one of Mt Aspiring’s three major glacial systems, 43 years after his death.

“We have so much knowledge and expertise in our SAR teams across the country, and within the mountaineering community, but a lot of information is held by individuals. People move on, and it’s not acceptable that information goes with them,” Spencer said.

“I thought ‘Wouldn’t it be great if we had a visual record of all the last known points of missing people, so that when we find remains or property, we could see at a glance who they could belong to’.”

Spencer set out to map the lost climbers on Aoraki Mt Cook using geospatial technology, and enlisted the help of the police geospatial team to start the production of his new map idea.

“They were keen to be involved, but only if we did it for the whole country. That absolutely made sense, so that’s what we did.”

Spencer said he gathered all the information held by police on every recorded long-term missing person in New Zealand over the past 50 years, including dental, medical and DNA records and details of clothing, jewellery and property.

This information was entered into an interactive geospatial map, then he carefully plotted the location of each person according to their last known whereabouts.

Spencer said he put the last pin on the map in February, 18 months after he began the project.

He credits the work of former SAR Sergeant Phil Simmonds.

“Phil saw the opportunity a while ago and started collecting information about missing people, but without the technology at the time, it didn’t come to anything more than a pile of files.

“I don’t think it can be underestimated what it means to families to be able to provide some form of closure. Items of clothing or property provide a tangible connection to a loved one in their final moments.”

The Missing Persons Map now sits with SAR co-ordinators across the country to use and keep updated.

The national missing persons co-ordinator, Detective Sergeant Jacinda Clarke, said what Spencer has achieved required “an extraordinary level of diligence and attention to detail”.

“I see it as a game changer for both the Search and Rescue perspective and the Missing Persons Unit, enabling us to return missing people to their loved ones more efficiently.”

Inspector Craig McKay, Canterbury operations and support manager, agrees.

“The enormous amount of work Carlos has put into this means we now have a lasting national resource to ensure the families of missing people know that their loved ones are not forgotten.

“This valuable resource will support the return of long-term missing people and their belongings long after Carlos has left police – what a legacy!”

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