The fish are biting along Northland's east coast this summer and so are thieves.
Police are warning visitors at popular beaches and holiday homes at Matapouri, Ngunguru and Tutukaka to be extra vigilant after 14 dishonesty offences have been reported since the start of December.
Acting area prevention manager for Whangarei and Kaipara Sergeant James Calvert called on anyone who noticed suspicious behaviour to contact police immediately.
"Unfortunately, there are a few people who are ruining the good times by breaking into other people's homes and cars. The disruption this simple act of disrespect can cause is huge and can completely ruin a holiday," Mr Calvert said.
"We really want people to come here and be and feel safe. To this end we encourage people to remove all valuables from their vehicles, and report any suspicious activity like people looking into cars or loitering around houses by calling 111."