The Kona Coast: Diving Hawaii’s Big Island

The big island Hawaiian is somewhat of a contradiction. Although it is the largest island in the Hawaiian island chain it still comes across as far from the maddening crowd. For diving, I discovered the leeward side of the island along Kailua-Kona coast offers a wealth of diving opportunities from coral reefs sprinkled with an array of colorful tropical fish to dramatic lava tubes and big animal encounters with dolphins and giant manta rays.
Large pod of spinner dolphins at Garden Eel Cove
Large pod of spinner dolphins at Garden Eel Cove.

For example, our third day on the Kona Aggressor II shaped up like this: “O.K., you go ahead and dive with the mantas, I still want to work on a few more images of the dolphins!”

It’s not often one is faced with such choices, especially when you are just a football field length offshore of a major tourism destination, and literally within sight of Hawaii’s Keahole Airport. Instead of the sound of surf breaking on the rocks on some far island in the Galapagos, we could hear the roar of a passenger jet taxiing down the runway.

Choosing between mantas and dolphins was the pleasant dilemma my wife Karen and I faced during our week aboard the Kona Aggressor II. When the boat first pulled into Garden Eel Cove, we were greeted by a large pod of spinner dolphins.

As in many of the large bays and coves dotting the Kona Coast, the calm waters provide spinner dolphins with a protected place for playing, rest, and, for the mothers, nursing their calves before returning to the open sea at night to hunt pelagic squid.

Reef manta ray, (Manta alfredi)
Reef manta ray, (Manta alfredi)

This same cove is also the site for one of Kona’s renowned manta night dive encounters. Not long after we got in the water, we found some of the big rays cruising back and forth, feeding along the edge of the reef, and occasionally making a break to get a closer view of us less-than-graceful snorkelers.

By the days end, I was bushed, and we still had a night dive with the mantas we were scheduled to do.

The Big island

I consider myself very fortunate to have enjoyed the opportunity to dive several of the Pacific and Indo-Pacific’s best venues: Coco’s, Galapagos, Socorro, Fiji, Vanuatu, PNG, Komodo, Truk, and more. But though I’d made many a connection through Oahu, until recently, I’d never devoted much time to discovering Hawaii’s underwater landscape. I had often heard fellow divers describe the diving as “O.K., but not in the same class as lots of other places in the Pacific.”

Now, I was learning otherwise. Granted, the waters of Hawaii don’t have the same high energy level of big animal encounters as the Eastern Pacific, or extensive soft corals, or the diversity of invertebrates and fish you would see further west in the Tropical Pacific. And yet, the elements of the diving experience here off the Kona Coast were a bit reminiscent of those more distant destinations.

Entrance to a large lava tube at Bob's Reef off the Kona Coast of Hawaii's Big Island
Entrance to a large lava tube at Bob’s Reef off the Kona Coast.

In geological terms, Hawaii’s Big Island is the youngest of the lot, and still growing, due the continuing volcanic activity of Kilauea on the island’s southernmost point. Below the jagged coastline of the island’s western coast, the underwater terrain typically follows a sloping profile that is broken up by an impressive number of pinnacles, lava tubes and arch formations that create a diver’s wonderland of sorts.

Dive site Stoney Masas, Big Island of Hawaii's Kona Coast
Dive site Stoney Masas, Big Island of Hawaii’s Kona Coast.

The best example of just how captivating some of these pinnacle formations can get is Stoney Mesas. The Mesas part of the name was quite fitting, as the site’s four giant flattop formations reminded me of red rock escarpments I had visited in Sedona, Arizona. Rather than red, these 40-ft/ 12 m-plus “mesas” are dark grey and adorned with hard corals and small fish. The tallest pinnacle, which has been named the Hive, towers 50 ft / 43 m off the bottom, and takes its name from the many small tropical reef fish such as triggerfish, butterflyfish and damselfish that swarm about its top like bees.

Green turtles along the Kona Coast are both plentiful and well accustomed to divers.
Green turtles along the Kona Coast are both plentiful and well accustomed to divers.

Another site that impresses on a grand scale is Au’au Crater. The underwater topography is quite dramatic—less of a round submerged crater and more like a v-shaped canyon, with vertical relief ranging 30 to 70 ft/ 9 to 21 m on one side, and 50 to 200 ft /15 to 60 m on the other as it funnels up and inward towards shore. The guidebooks describe it as a “good spot for pelagics such as oceanic white-tip sharks, hammerhead sharks, and large jacks.” Although I watched the drop-off for something large, a sleeping sea turtle was as good as it got. But even without the big critters, Au’au was still immensely enjoyable, with plenty of small Technicolor denizens to eat up a gig or two of my camera’s flashcard.

Another interesting site that’s usually on the diving itinerary is Aquarium in Miloli’I Bay. We arrived by boat, but this is also a popular shore diving site. I felt the name Aquarium was a little misleading, as the fish life was just average. What I did find special about the place was the underwater topography.

Dive site Aqauruim off the Kona Coast of Hawaii’s Big Island.

In addition to fields of coral-covered basalt rock, the shallower zone from a max depth 40 ft / 20 m to surface features some extensive grottoes and caverns created from collapsed lava tubes, many with openings in their ceilings that allowed sunlight to spill through.

The list of dive sites visited while on board the Kona Aggressor II were many and varied, with names like Catacombs, Oz, Rainbow Reef, Pohoe Bay, The Maze and Turtle Pinnacle to name a few. Of this roster, the only site that failed to impress was Turtle Pinnacle. Located at the north end of Kona coast, this site is highly publicized for green turtles that apparently gather atop a pinnacle to be cleaned by mobs of yellow tangs. Unfortunately And because the site lies right outside the entrance to the largest and most active marina on this coast, the visibility was less than on most Kona sites, dropping to a mere 50 – 75 feet. By contrast, we were thrilled by sites like Meadows, Mantaville and Garden Eel Cove near Keahole Point. Another favorite site called Manta Theater provided encounters with large reef manta rays and spinner dolphins.

Dive site Turtle Pinnacle, Kona Coast, Big Island of Hawaii
Coral reef at the dive site Turtle Pinnacle on the Big Island of Hawaii.

In general, at all of these sites, the underwater terrain sloped gently from the surface, where the waves would break on the rocks, down over lava formations comprised of rubble and boulder fields before rolling off more steeply around 80 to 100 ft /24 to 30 m. Beyond that point, the bottom contours dropped much steeper away, and for the most part not all that interesting as the amount of marine life grew far a few between. Perhaps it gets more interesting below the 200 ft / 60 m mark. I had neither the time or the right equipment to see for my self, so I was content to stay in the shallows where conditions were superb, with underwater visibility averaging between 75 and 125 ft / 22 to 36 m. it was also where most of the life was, including an abundance of stony hard corals, which appeared to be almost the sole variety found here around the Big Island.

As mentioned earlier, the island is still relatively young, geologically speaking. Then there is water temp, which can get a bit cool averaging 70 -75 F / 21 – 24 C from November to April, warming slightly to 76 – 79 F / 24 to 27 C during the months of June through September. In addition to the coolish waters, the Hawaiian Islands only have a tenth of the species of coral found in the Tropical Western Pacific. Given this combination, you might think there would be hardly any coral at all. Yet at most of sites visited, what corals there were appeared to be healthy and surprisingly pristine (a word I don’t use lightly) with heads showing uniform coral polyp coverage and coloration.

Peacock Grouper (Cephalopholis argus) - Hawaii
Peacock Grouper (Cephalopholis argus)

I was also impressed with the variety of macro subjects, from football-sized peacock grouper to butterfly fish, tangs, nudibranchs, and flatworms, as well as my favorite: the pygmy angels.

Potter's Angelfish (Centropyge potteri), Kona Hawaii
Potter’s Angelfish (Centropyge potteri)

The region’s most common species of endemic pygmy angelfish is the Potter’s angelfish (Centropyge potteri). Like most species of pygmy angelfish, it is smaller than a child’s palm, and features a highly distinguishing color pattern comprised of reticulating lines over the body and fins starting with bright orange on top ending with brilliant royal blue around the lower fins and tail.

Bicolor Anthias (Pseudanthias bicolor), Hawaiian Islands
Bicolor Anthias (Pseudanthias bicolor), Hawaiian Islands

Among the more colorful species is the bicolor anthias (Pseudanthias bicolor). The Hawaiian Islands in general have a very limited variety of anthias, through Kona has more than the other islands. Those you do find typically favor ledges and wrecks deeper than 60 feet, and finding one become a special treat.

Moray eels are highly abundant in the Hawaiian Islands, but just like the region’s angles, nearly all – from the more common white mouth moray (above) to the more flamboyant dragon moray – are predominantly small species, seldom longer than 2 feet in length.

If you want the chance to do some whale-watching, November to March is your best bet for seeing humpbacks and pilot whales, although the seas can be a little rough as you move offshore and out of the lee of the island. There is one more relatively large creature divers might encounter, the Hawaiian monk seal. What makes this marine mammal special is that they are exclusively endemic to the Hawaiian Islands and found nowhere else in the world.

When I was last in Kona, sightings of this critically endangered animal were more rumor than event around the Big Island, but lately, divers have been graced with the presence during some night manta dives. Talk about your surprise encounters in the dark. But, if it should happen to you, consider yourself extremely lucky! Because most divers that visit the Hawaiian Islands are more likely to ever see one.

You can learn more about these animals, as well as how you can help protect them, by visiting www.monksealfoundation.org.

Considering all that this area has to offer, I was not surprised to learn that many divers return to Kona repeatedly. I hope to do the same some day soon.

Stay to Savor the Coffee and Macadamia Nuts

Top Left - Polynesian Petroglyph at the petroglyph fields at Puako historic site. Top Right – waterfall on the windward side of the island.
Top Left – Polynesian Petroglyph at the petroglyph fields at Puako historic site. Top Right – waterfall on the windward side of the island.

Before or after a tip on the Kona Aggressor II, I highly recommend reserving a few days to rent a car and explore the Big Island. There is a whole lot more to this island to see and experience than some cheesy luau at a big resort.

The Big Island of Hawaii is a place of multiple personalities. Nowhere else will you find both tropical black sand beaches and snow-topped mountains within sight of each other. The island’s highest summit is Mauna Kea at 13,796 ft /4345 m above sea level. Along with her sister summit Mauna Loa with an elevation of 13,678 ft/4208m, they are the highest mountains in the Hawaiian island chain.

Lava tube on the southern end of the Big Hawaii.
Lava tube on the southern end of the Big Hawaii.

The eastern side of the island is a verdant rainforest that gets 200 inches of rainfall a year, creating spectacular waterfalls, while parts of the western Kailua-Kona (leeward) coast is almost as dry as a desert. At the southern end of the island is Kilauea, one the world’s most active volcanoes.

Downtown waterfront district of Kailua-Kona.
Downtown waterfront district of Kailua-Kona.

The one significant settlement on the Kona Coast would be a bit of a stretch to call a city. The downtown waterfront district of Kailua-Kona sees tourist activity on the days when a cruise ship docks, but it otherwise has a small-town feel. The shore is not lined with high-rise hotels like Oahu, and many of the nearby beaches are still only sparsely populated.

The true Hawaiian’s legacy is still represented through ancient Polynesian Petroglyph fields at Puako or Pu’uhonua o Honaunau, the royal Place of Refuge, which also features a fantastic shore dive with a chance for snorkeling or diving with sea turtles and spinner dolphins.