Whale-watching season arrived Tuesday with the first sighting of a “medium-sized” humpback off Kauai’s northwest coast. In recent years, the North Pacific humpback whale population has been estimated at more than 20,000, with some 12,000 migrating annually to Hawaii waters for breeding, calving and nursing.

The National Oceanic and Atmospheric Administration’s Hawaiian Islands Humpback Whale National Marine Sanctuary — a 1,366-square-mile management zone edging portions of the state’s islands — provides a safe haven for the 45-ton wonders. They’re also protected by federal and state wildlife laws.

Vacation rental blues for investor

Call it karma. An out-of-town investor wants to operate a short-term vacation rental business in Hawaii. He buys a house already being used for that purpose, only to learn that a) the property doesn’t have a license and b) the city is about to clamp down on illegal rentals.

That’s the gist of a lawsuit filed by Carsten Mikkelsen, a Texas man who bought a six-bedroom Portlock home for $2.3 million. He’s suing the seller and the real estate agency, claiming they failed to disclose that he can’t rent the home for periods shorter than 30 days.

The suit encapsulates a chief argument against short-term rentals: the likelihood that speculators will transform residential neighborhoods into tourist-resort zones.