_ How do you sneak up on a one-ton manta ray? You don't, it sneaks up on you._

__**Giant manta ray with 12 ft wingspan hovers over cleaning station.**

The trick to successful stalking is understanding the habits of your quarry. If you want to see manta rays up close, consider taking a trip to the Micronesian island of Yap, the manta ray capital of the Pacific.

Yap is a small island in southwestern Micronesia surrounded by a barrier reef that encloses a protected lagoon. This shallow, nutrient-rich lagoon is a key feeding ground for more than 100 mantas that gorge on tiny plankton blooms in the warm shallows.

Since discovering this underwater phenomenon in 1988, Bill Acker has built a business based on the mantas, including a hotel and dive center. Today, Acker is probably one of the world's most knowledgeable experts on manta ray behavior. He has devoted thousands of hours to observing these creatures and learning their wily ways.

DIVE TECHNIQUEGetting close to giant manta rays requires a special technique, and Acker has refined it to almost an art form. Every new visitor is given an orientation seminar on how mantas behave and, in turn, what divers should do to get close to these majestic animals.

The manta ray is an open-water creature that only comes into the shallows for feeding and cleaning. It spends most of its time roaming the deep ocean and avoiding its predators Ð killer whales and large sharks.

If a diver tries to directly approach a manta in open water, it is likely to bolt and swim away as quickly as possible. After observing this behavior on many occasions, Acker has developed a technique for getting near these creatures without alarming or stressing them.

For the most part, Yap's manta diving is conducted in the channels that lead from the open ocean to the confined lagoon. These are the manta highways to the feeding grounds. In addition, the channels are used as cleaning stations where tiny reef fish pluck parasites from the mantas.

Acker's dive boats anchor along the sides of these channels, staying clear of the manta traffic but providing easy access to these undersea freeways. Prior to the dive, every visitor is cautioned to avoid swimming toward the mantas or attempting to touch them. Manta riding is absolutely forbidden.

The best method for successful manta stalking requires divers to swim to the bottom of the channel and remain motionless. So there you are, facing into the current and hugging the bottom of a sandy channel, when a giant manta ray pulls up to check you out. Being observed by a creature that weighs close to a ton with a wingspan of 10 feet is an awesome feeling.

If you remain perfectly still and breathe slowly, the manta will often position itself right above your head and remain stationary. Apparently some mantas enjoy the tickle of a tiny trail of exhaust bubbles on their bodies. However, a loud explosive burst of exhaust bubbles will cause the manta to depart immediately. Slow, relaxed breathing is crucial.

Divers may wonder how manta rays manage to remain perfectly still and so precisely positioned. The manta's body shape is almost a perfect airfoil, allowing it to stay stationary as long as a light current flows over the wings. It is this current that provides the lift needed to keep the manta from settling to the bottom.

The best time to dive with the mantas is during an incoming tide when clear ocean water flows into the lagoon. During these periods, underwater visibility in the channels can approach 80 to 90 feet, presenting an opportunity for underwater photography or videos.