Double-dog dare you to swim with these giants in Hawaii

It may seem like your worst nightmare: a primeval underwater monster swimming straight toward you, its huge, ugly mouth wide open.

But the manta rays are gentle giants. That’s just one of the things you’ll learn on the Big Island of Hawaii during an on-land lecture or, yes, even a swim alongside the massive creatures.

The Manta Learning Center at the Sheraton Kona is celebrating its first anniversary this month. The hotel partnered with the Manta Pacific Research Foundation to create the center, not suprising because the resort is beside Keauhou Bay, one of the world’s prime viewing spots for the rays.

Exhibits and a video tell you about the marine animals whose massive wings, which propel them through the water, can span 20 feet. They can be amazing acrobats, doing somersaults. Because of their size, they sometimes are feared, but they generally are docile creatures who don't mind humans.

You can hear more during educational talks at the center at 6 p.m. Mondays through Saturdays.

If you’re there Aug. 16-22, you can also can help raise money for the nonprofit foundation.

From 8 a.m.-2 p.m. Aug. 16, nature artist Patrick Ching will begin work on three paintings depicting manta rays. You can watch him work along the hotel’s inner pool deck. The paintings will be sold during a fundraiser from 6-8 p.m. Aug. 18.

An open house from 5:30-7 p.m. on Aug. 20 will feature the foundation’s Keller and Wendy Laros speaking about the local manta ray population. The event is free.

A complete list of the anniversary week activities can be found online.

The rays are best viewed after dark, when they swim gracefully through the bay, gathering plankton in their otherworldly mouths. They’re regularly spotted from the deck of the hotel’s Rays on the Bay restaurant and lounge.

Much closer encounters are offered by Eka Canoe Adventures, which offers swims among the bay’s rays nightly at 7:30 and 9 p.m. The experience costs $89 for children and $99 for adults and includes snorkel gear. The company offers a guarantee: guests who don’t see a ray can come back another night at no extra charge.

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