If you're looking for a last-minute trip to Cape Cod during the 'busy' season, you might be in luck. Summer rentals are sitting empty.

• It's not too late to book a short-term vacation rental to Cape Cod, Massachusetts, this summer.
• The vacation hot spot has a surplus of rentals, according to local real-estate groups.

There's something fishy going on in Cape Cod, Massachusetts.

Even as the vacation hot spot enters its busy season, locals are seeing the demand for vacation rentals soften. The occupancy rate is down 20% from last year, according to the Cape Cod & Islands Association of Realtors.

The slowdown means it's not too late for visitors to book a summer stay. Airbnb still has more than 1,000 listings available for a week in July or August, Insider's search showed. Vrbo also lists several hundred properties, though some may be duplicates across the two sites.

It's a bit of a mystery how the coastal wonderland became so quiet, according to a new report by The Boston Globe. The reporter Beth Teitell wrote, "Have the sharks and the traffic and Airbnb's tyrannical departure instructions finally scared off visitors? Or are there suddenly too many listings?"

Locals say it's all of the above.

Ryan Castle, the CEO of the real-estate association, told the Globe that a popular theory was that people who bought a second home on the Cape during the pandemic were now taking vacations farther away, particularly as a strong dollar made it cheaper to travel overseas.

After listing those homes on sites like Airbnb and Vrbo, the supply of vacation rentals is through the roof. State officials said the number of Cape rentals registered with the state flew to more than 16,000 in April, an increase from 12,100 in March 2021.

Even still, owners are pushing prices higher, which lowers demand, Castle said. The real-estate group said the average daily rate had climbed to $619 from $525 last summer.

Others say the Cape has lost its luster, which would explain the vacancies. A shortage of seasonal workers has created staffing challenges for local businesses, which have warned tourists of longer waits and reduced hours. There's a scourge of scammers setting up fake rental listings to steal from tourists. And sightings of white sharks in the waters around Cape Cod have increased rapidly in recent years as the number of receivers used to detect them has increased.

"Maybe a week on Cape Cod is just not as glamorous or comfortable as it used to seem," Annie Blatz, a sales manager with Kinlin Grover Compass, told the Globe.