Locating the Wanderer with NZ Developed Tool

By Julia Mahony

Pulsing beeps are a sweet sound for Ray Harkness.

Ray is the Wellington region’s volunteer contact for WandaTrak, an electronic device used to locate missing people with disabilities such as autism, dementia, and Alzheimer’s. An active member of LandSAR/AREC since his retirement from the media industry and now Wellington Wander Search Charitable Trust, Ray was shoulder-tapped by police to assist with WandaTrak searches. Through the Trust Ray co-ordinates distribution of the tracking pendants worn by those susceptible to wandering and becoming lost.

WandaTrak pendant and watch

WandaTrak pendant and watch

Developed by Canterbury’s Ian Trethowen, WandaTrak tracking units are held at Police stations or by trained AREC members. About 15 pendants are in use around the greater Wellington region. They emit pulses every 1.5 seconds on specific frequencies, at a range of between 1km in urban areas and up to 5km in elevated positions.

For Ray, WandaTrak is a voice for those who cannot call out in response to searchers. “For instance, autistic kids love the bush – perhaps it has a calming effect. Sometimes they don’t vocalise, so if they go missing, you can’t call their name and expect an answer.’’

Searches using WandaTrak are narrowed down by triangulation, starting with a vehicle search temporary roof mounted antenna. “You start hearing beeps and if you continue driving you stop hearing beeps,’’ Ray explains. “You localise the area, then search on foot with a directional aerial. The pulses get louder, then fade away and you pinpoint the signal. With a bit of luck or in favourable terrain, it can be very quick. If the weather’s bad, or it’s an area with lots of bush, tracks or paths, it may be as well to bring in two tracking teams to work towards each other.’’

Ray knows to be prepared for anything. During a recent search for a dementia sufferer in Canons Creek, Porirua, Ray and a member of Police found their task quickly move from an urban search into bush and when found the subject was still heading away from civilisation, towards swamps and ponds.

Pendants are totally sealed and wearers wash and swim in them, until Ray cuts them off every six months. “The pendants go back to the manufacturer in Waipara, the case is changed, a new battery installed and they come back with a new neck cord, which forms the transmitter’s antenna.’’

Ray says there are other excellent devices from overseas that use GPS positioning. However, this technology currently needs recharging every two or three days. Because they depend on a cellular phone network, determined wanderers can often end up out of range of a cell tower.

Hearing the WandaTrak beeps is always a relief for Ray “They signal the missing person is still local. They haven’t hitchhiked, used their Gold Card to travel away, or used a bicycle to cover a great distance.’’

He describes a WandaTrak search as like an extension of a radio “fox hunt’’ or direction finding (DF) exercise.

Head of Wellington police search and rescue, Sergeant Anthony Harmer, says WandaTrak can shave hours off a land search. “They can now be as quick as 15 minutes with two people searching. WandaTrak is one of the finest tools with which to help mentally impaired people who wander. Ray Harkness is invaluable to police, who could not operate without community-minded volunteers like AREC. It’s a partnership.’’

For more information on WandaTrak the Wellington Wander Search Charitable Trust go to http://arec.info/wanda-search/