"LandSAR has selflessly supported the search and rescue effort to return these beautiful souls to their family and friends.
"This doesn't come close to repaying the work being done by LandSAR - along with the police, defence force and fire service - but I hope it can at least convey the immense gratitude of Jessica's family, Dion's family and all their friends," Dominic O'Connor wrote.
Poor weather in the area has hampered search efforts. Police said today's search has been suspended and they are planning to resume once the weather improved.
Yesterday, all but one of the teams searching for the pair had been pulled back due to bad weather. Reports said heavy rain was continuing in the area, which Jess O'Connor was said to be familiar with.
A friend and colleague described her as calm and well liked among kayak guides in the Abel Tasman National Park.
The Marahau-based guide who was also her former flatmate said she borrowed a map from him to explore the Anatori River area where searchers have been looking.
The guide, who declined to be named out of respect for the families, said Jess was a calm, solid-thinking, "very fine person" who was well equipped to handle the outdoors.
He understood her brother, Dominic, was based in the UK.
"Anatori is a bit of a tradition with outdoors folk and locals, driving or walking to the Kahurangi lighthouse, beach walking, fishing and exploring the creeks and rivers inland.
"Jess was making plans to explore more during lockdown, and borrowed a map from me to make loose plans to explore the Anatori River catchment, which is exactly where they've been searching."
He said what might have happened to the pair was a "blank canvas" and that anything was possible.
Dominic O'Connor said the families were taking solace in the commitment and hard work of the emergency response efforts, and they knew they were doing everything they could to bring Jess and Dion home.
"New Zealand's caring, never-give-up attitude is encapsulated within LandSAR - an organisation of volunteers who give up their time and put themselves in harm's way to undertake rescue efforts throughout New Zealand.
"We hope and pray for the safe return of Jess and Dion."
