MARIN COUNTY, Calif. (KRON) — The search for 77-year-old Carol Kiparsky and her husband, 72-year-old Ian Irwin, continues Thursday with a few changes.

The couple went missing on Valentine’s Day after renting out a cottage on Via de la Vista in Inverness.

Searchers have looked on foot, on horseback and in the water. But the case remains a mystery.

The Marin county Sheriff’s Office said it has received four independent alerts from Cadaver K9 teams near Shell Beach.

But officers say will all of the efforts and resources used in the search, Carol and Ian would have been found by now if they were responsive or on land.

Therefore, the search went from a rescue mission to a recovery mission on day six since their disappearance.

“We’ve worked tirelessly combing through all leads and areas surrounding the cottage they were vacationing at and are now calling this a recovery mission. We have been in close contact with family and will continue to search for Carol and Ian. Our thoughts are with the Kiparsky and Irwin family during this difficult time.”

The Marin County Sheriff’s Office

The sheriff’s office has laid out the following plan for the next couple of days.

The plan goes as follows:

Thursday, Feb. 20 – An airplane, US Coast Guard helicopter and a boat will be used to search the area from the air, Tomales Bay and the shoreline.

Friday, Feb. 21 – Jet skis, National Park Service boats, an airplane and drones will be used to search Tomales Bay and the shoreline.

Saturday, Feb. 22 – Another search will be planned out using ground searches, K9 teams, NPS boats, an airplane and drones.

Sunday, Feb. 23 – NPS boats and an airplane will be used to search Tomales Bay.

Monday, Feb. 24 – Jet skis will be used in the search.

Officials ask the community to observe their surroundings in the Inverness area and to report anything out of the ordinary or suspicious to the Marin County Sheriff’s Office.

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