Shaken, Stirred and Moved by Manta Rays
If I am ever abducted by aliens, I hope they are as gentle and peaceful as manta rays.
I have long wanted to dive with the manta rays off the coast of Big Island. In Hawaii, dive operators claim the experience is the number one night dive in the world, and I have heard many stories about it. How the manta ray gatherings started when a hotel discovered that the spotlights it beamed into the ocean at night attracted the behemoth creatures. How manta rays fly through the water as graceful as ballerinas. How the week before my dive a humpback whale joined the dance, followed by a small school of spinner dolphins.
Other stories make my skin shiver. Like the one about Frankie. With his ever-gaping maw revealing rows of jagged teeth, Frankie is a moray eel. He lives at Garden Eel Cove, our dive site. Frankie feeds at night, weaving himself through legs and wending his way around divers as they sit stationery on the ocean’s bottom and shine dive lights to attract plankton—the food of manta rays.
Scuba Diving in Hawaii
In order not to think about Frankie, I focused on something equally unpleasant to me but not nearly as toothy: The cold.
I turned to Danny, our dive master with BottomTime Hawaii, “You’re going to have to talk me into this,” I said, shivering in my very wet wetsuit. We had already completed one dive—a one-hour excursion at a max depth of 91 feet, and with the sun tucked securely below a voggy horizon, I was chilled. It’s hard to stop shaking once you start, no matter how much you remind yourself that you’re in tropical Hawai'i and the water temperature is 79 degrees.
For his part, Danny was diving in a short-sleeve rash guard and swim trunks. He looked more like a surfer than a diver. “Aren’t you going to put on a wetsuit?” I had asked him earlier.
“No need,” he said.
Our captain—his name is Mike but on the boat, he goes by Vinny, because, as he says, everyone is named Mike—shook his head. “Danny doesn’t need a wetsuit,” he said. “He already has an extra layer.” It’s true. Danny may dress like a surfer, but he is built more like a heavyweight wrestler.
Exploring Hawaii’s Reefs
As editor of OutriggerHawaii, I had assigned myself the task of learning more about Hawaii’s reefs. That meant, of course, I had to get wet. I had to don mask and snorkel, and I had to explore the undersea world of Hawaii. And not just on my home island of Kauai, but around the archipelago, too. Oh, darn.
But first, I headed to the bookstore, because the fish ID guides that I already owned dedicated very few pages to one of the main reef-building organisms in the ocean: coral. There, I discovered two invaluable books: The textbook-like Hawaiian Coral Reef Ecology by David Gulko and the Cliff Notes version, Corals of Hawaii by Douglas Fenner. I learned there are only five common corals in Hawaii, all belonging to the phylum cnidaria, which means corals are related to Portuguese man-of-war and various jellies. All contain unique stinging structures called cnidae, which are the defining feature of this phylum and usually used for the capture of such foods as small, planktonic organisms and dissolved organic matter. (Hmm, plankton. That’s just what the manta rays were after.)
After the bookstore visit, I signed up with Reef Check, a non-profit, volunteer coral reef monitoring organization, and I discovered it gave me a good reason to go snorkeling or diving at least once a month. “It’s for the reef,” I would tell my husband as I headed out the door to survey the marine life living at some of Kauai’s most popular beaches.
Then, I visited with volunteers from the ReefTeach project at the popular Kahaluu Bay in Kona. The program educates beachgoers on the precious corals growing there and how best to care for them and the ever-present green sea turtles that like to nosh on the limu growing in the bay. (Here’s a tip: Use mineral-based sunscreen and put it on at least 15 minutes before hitting the water. Better yet, skip the sunscreen and wear a rash guard.)
After studying the reef’s smallest creatures—coral polyps—I decided it was time to explore the other end of the spectrum. With a wing span up to 30 feet, manta rays are some of the largest marine animals to frequent the reef. Too, I wanted to compare my experience diving off Kauai with that on the other end of the archipelago, Big Island.
A Bounty of Coral off Big Island
I first learned to snorkel years ago in Acapulco, Mexico. In addition to forgetting to breathe, I kept lifting my head out of the water and sputtering to my husband, “Did you see that?” I’d suddenly reverted to a child at Christmas. Each colorful fish was an exciting, new present.
When I plunged into the ocean off Kona for my pre-manta ray dive, I was that child again. I popped above the surface and squealed to Danny, “Look at all that coral.”
On Kauai, I was used to a more monochromatic reefscape with scattered mounds of coral. Here, a carpet of coral, of all colors and kind, blanketed the ocean floor. Yellow-green lobe coral. Thickets of blue finger coral. Bushes of creamy cauliflower coral. Sheets of rice coral. It was a cornucopia of coral.
The more I looked, the more I saw. A red pencil urchin tucked among blue octocoral. A yellow frogfish draped on yellow lobe coral—Danny had to point out that one. A whitemouth eel entwined in cauliflower coral. And, peering out from the branches of antler coral, two arc-eye hawkfish.
Manta Ray Anatomy Lesson
It’s not only the smaller marine creatures that live in and around the condominiums of corals; even the big guys cruise the reef. Yes, there are sharks on the reef; some who even live there. Dolphins sometimes swim by. Monk seals visit. And, occasionally, manta rays.
Did you know manta rays are considered cousins to sharks? It’s because, like sharks, their skeletons are made of cartilage, and they have gill slits instead of gill covers. But manta rays look nothing like sharks. Rays have flattened, triangular-shaped bodies with fins as wings. In my opinion, manta rays resemble what alien spaceships are supposed to look like.
Unlike sharks and other rays, mantas are filter-feeding plankton eaters. Plankton are minute organisms that drift with the ocean’s currents. Weighing upwards of 5,000 pounds, manta rays have to eat a ton of plankton.
While most mantas have solid black backs, their white bellies are often speckled. Some have just a few black dots; others have big, black, Rorschach blotches on their bellies. Like a thumbprint or even a whale’s tail, the white underside of a manta ray is quite unique to that manta. Captain Vinny said he could easily identify 20 out of the 100+ manta rays that call on Garden Eel Cove.
And while we’re on topic of anatomy, manta rays are not the same as stingrays. Mantas do not have poisonous barbs. Nor do they have teeth—except for a few vestigial remains on their lower jaw.
Abducted by Manta Rays
It was time to take the plunge. Danny astutely reminded me that I would actually be warmer in the water than standing on the boat in my damp wetsuit. I stepped into the water in a giant stride and discovered he was right.
Before I could get situated—mask snug, air in my BCD, regulator in my mouth, gauges hanging off my body and dive light and camera strapped to each wrist—I heard someone say, “There’s one.”
Thirty-five feet below, I tried to kneel, but my big fins got in the way, so I sat reclined on my air tank and watched the ballet above me. To keep me securely on the bottom, Danny plopped a rock in my lap. My dive group of seven formed a circle and pointed our dive lights straight up. This attracted the plankton, which, in turn, attracted the manta rays. Four mantas wove and dove above us. They were easily wider that the beam of our dive boat and, with their tails, about as long.
They passed so closely over our heads that, even though Captain Vinny said the mantas wouldn’t hit us, I instinctively ducked a couple times.
The mantas moved about as fast as high, cumulus clouds on a bright, sunny day and that put me in a meditative mood. As I stared down their wide, open mouths, I wondered if mantas started drooling when they saw divers slip into the sea, like Pavlov’s dogs. I wondered if they really are from another planet. If that’s why they looked like spaceships.
As a manta made another pass over my head, I wondered if the surge of water that rocked me to and fro was caused by the movement of the gentle giants—they surely displaced quite a bit of water—or if the moving tide was caused by the full moon glowing on the surface of the water.
Soon, I was shaken from my reverie, literally. I was cold again. This time, though, there was no question about my actions. I wasn’t about to leave this spot until my air ran out.
Thankfully, Frankie waited until we dispersed to come out of his lair.