Kimbe Bay, Papua New Guinea

Kimbe Bay pulses with life: its coral reefs hold more than half of all species on Earth, a rainbow jungle that more than 900 reef fish species call home.  Kimbe Bay is located in the Bismarck Sea, a key area in the global center of marine biodiversity.  The Coral Triangle and Kimbe Bay lie almost centrally within this.  Its marine life is remarkable: Kimbe Bay possesses 4 critically endangered, 11 endangered and 173 vulnerable species.  These include the Largetooth Sawfish (Pristis pristis), Pondicherry Shark (Carcharhinus hemiodon), Olive Ridley (Lepidochelys olivacea) and Leatherback Turtles (Dermochelys coriacea), Scalloped Hammerhead (Sphyrna lewini) and Sei Whale (Balaenoptera borealis). 

Kimbe Bay’s secret to its rich healthy marine ecosystem is its complex and diverse bathymetry (the measurement of depth of water in oceans, seas or lakes).  A narrow coastal shelf fringes the coastline of the bay, descending to oceanic depths of over 1,000m.  Along this coastline, fringing nearshore emergent reefs are neighbors to seagrass beds, mangroves and river estuaries forming multiple land-sea interfaces.  

Coral reefs in Kimbe Bay are as striking as they are fortunate.  Its reefs have been assessed as high diversity and high coral cover sites –  amazingly with relatively low human impact.  Of the 173 IUCN Redlist vulnerable species, 159 of these are scleractinian corals.  The endangered coral Cantharellus noumeae is also found in the Bay.  In 2018, researchers from James Cook University undertook upper mesophotic surveys in Kimbe Bay, which resulted in reporting a species of Black Coral (Antipatharia) that had not been previously described to science, let alone the Bay itself. 

The occasional sightings of orca, pilot whales, whale sharks and other large marine life passing through Kimbe Bay often with young are also an indicator of the importance of Kimbe Bay as a habitat for these animals. 

The combination of a rich and varied fish fauna, well developed coral reefs, and a spectacular, relatively pristine environment, is ample justification for the establishment of a special conservation status for Kimbe Bay.

The reef flat of the main reef at Agu is only 1-2m (3-6ft), with a very narrow ridge dropping away to the south.  Just under the boat, the mooring is situated at a depth of 5m (16ft), with a gradual ridge sloping down to 20m (65ft) with a ledge at 35m (115ft) before dropping away into the deep.  It is a narrow ridge, so you can either choose to swim along the ridge or along the wall, and either offers a great dive.  If there is a good current, hop over to the current side of the ridge and you will see schools of barracuda, batfish, rainbow-runner, big-eye trevally, even a couple of gray reef sharks or dogtooth tuna.

The ridge is covered with hard coral, with many sea anemones with pink anemone fish.  In the shallows, hard corals and damselfish make a nice combination and good place to do a safety stop.  If you come back from the ridge and still have some spare air, you can explore the wall on the main reef where you should find a good selection of nudibranchs.

Anne Sophie’s Reef is one of Kimbe Bay’s most diverse reefs.  Situated at the northern tip of the bay, it is just over an hour’s boat ride from Walindi.  The main dive site is at the end of the reef structure running south away from one of the coastal islands.  The top of the reef is in about 5m (16ft) of water, it slopes down onto a sand bottom consisting of small coral bommies covered in a variety of soft coral.  The maximum depth onto the sand is 23m (75ft). The reef is made up of a vast amount of varying corals, from hard brain coral and tubastea branching corals to elegant sea fans, black coral trees and barrel sponges.

Along the sand bottom garden eels and goby shrimp can be seen.  On the top and along the sides, crabs, scorpion fish, nudibranchs, flatworms and dart fish can be found.  The water column surrounding the reef is abound with fish life such as barracuda, trevally, bat fish, unicorn fish, Moorish idols, parrot fish and damsel fish.  On most dives grey reef sharks and turtles have been seen.  The dive site can vary with the water movement, from calm, still water to a moving current across the top.

Bradford Shoals is a dive site of the sea mount type, an isolated reef that rises from considerable depths to within sixty-five feet (20 meters) of the surface.  The reef structure is predominantly flat plates of hard corals, and adaptation allowing maximum utilization of the reduced sunlight at that depth.  There are also many colonies of Leather Coral, Sarcophyton.  The reef slopes downward from its twin summits to a lip at about ninety feet (27 meters), after which the drop is almost sheer vertical.

Among the corals are a number of the smaller species of reef fish such as fairy basslets, butterfly fish, and damselfish, and quite a number of pink anemone fish.  Interesting as these are, the main reason for visiting Bradford Shoals is big fish, especially pelagics.  The reef seems to act as a magnet for these fish and on any dive one is almost certain to see large schools of Barracudas, Pinjaro, Big Eye Trevally, Dog Tooth Tuna, Unicorn Fish, Fusiliers and Sharks, either Grey reef sharks or on rare occasions a Hammerhead.

Christine’s Reef begins as a submerged saddle between a large reef and two much smaller detached reefs.  While it is quite possible to swim down the saddle, around the first of the detached reefs, and then back up the saddle, the

saddle itself is the most interesting.

Starting at the main reef a diver descends down across a thick growth of staghorn corals and quickly reaches the saddle proper to find a beautiful combination of large gorgonian fans, red whip gorgonians, and a few barrel sponges, many of which are adorned with colourful crinoids.  The larger of the two dark red sea fans at the southern end of the saddle is a particularly good place to observe longnose hawkfish.  The red sea fans also make an excellent backdrop for photographing the hawkfish or any other fish willing to pose in front of them.  At the northern end of the saddle, just past the gorgonian fans and barrel sponge, are several sea anemones occupied by families of clown anemone fish.

North Ema Reef has as its main feature a deep bommie attached to the main reef by an even deeper saddle.  The bommie is covered with gorgonian sea fans whose white feeding polyps contrast with their red skeletal structure. Beneath the sea fans is an under story of leather coral.  There are also a few colonies of burning bush soft coral. 

Because one can remain on the deep bommie only briefly, making a shallow circumnavigation of the main reef is a pleasant way to finish the tank of air and gain an extra measure of decompression.  The east side of the reef is an almost sheer wall along which sea anemones occupied by pink anemone fish occur at almost regular intervals in the ten to thirty foot (3-9 meter) depth range.  The south end of the reef has a more gradual hard coral slope with typical reef fish and an occasional passing school of barracuda.  Returning along the west side wall, look for the large sea anemone with orange anemone fish, one of the less common species of Kimbe Bay.

South Ema Reef – if any dive site in Kimbe Bay can be said to have it all, it would have to be South Ema.  Huge barrel sponges, red whip gorgonians, colourful soft coral, and a deep swim through are just a few of the attractions. 

Descending along the saddle from the main reef a diver passes a few gorgonians and plate corals at just below thirty metres (100ft).  Just off the west end of the shoulder, where it begins to rise again, is the entrance to the swim through cave.  Entering through the smaller opening on the north side allows one to better appreciate the gorgonians and sponges that frame the much larger opening at the southern end.  Ascending upward from the shoulder onto the large attached bommie one passes a stand of Dendronephthya soft coral, thickets of red whip gorgonians, and into a cluster of barrel sponges, the largest of them almost two meters (6ft) tall.

The crest of the bommie is covered in hard corals with occasional sea anemones.  Fusiliers, trevally, and sometimes barracuda cruise the waters above the bommie.  Leafy scorpion fish can also occasionally be found on South Ema.

This site is Walindi's House Reef and is a 2 minute boat ride from the jetty.  Hanging Gardens is a dive site situated along a sheer vertical wall starting from just below the surface and descending to a depth of about ninety feet/thirty meters where the wall meets a sand and rubble bottom.  Along the wall are numerous ledges and overhangs, as well as several large cut backs into the cliff.

The site is named for the many tangles of rope sponge hanging down along the face of the cliff, some up to ten feet/three meters in length and with crinoids clinging to them.  In the shaded areas beneath overhangs and within the cuts are prolific encrusting communities dominated by sponges and sea squirts.  These encrusting communities are excellent habitats to search for many small macro subjects like nudibranchs, feather duster worms, and living shells. 

Hanging Gardens is also an excellent choice for a night dive when many of the nocturnal animals that hide in the caves and crevices come out to forage.

Inglis Shoal is another of Kimbe Bay’s sea mount type of dive site.  The isolated reef rises from considerable depths to forty-five feet (14 meters) below the surface.  As with Bradford Shoals, the basic reef structure is primarily composed of flat plates and mounds of non-staghorn corals.  In addition there are also large stands of a greyish soft coral, probably Nephthya, and numerous sea anemones, several of them with brilliantly coloured columns.  The different sea anemones are inhabited by at least three species of anemone fish- Clarks, Pink, and Spine-cheek.

From the bare patch at its crest, the reef slopes downward on all sides to a lip at about eighty-ninety feet (24-28 meters), after which it falls away in sheer vertical walls.  Like Bradford Shoals, the main appeal of Inglis Shoals is fish action in the waters above the reef.  Schools of barracuda, batfish, trevally, fusiliers, or unicorn fish are there on virtually every dive. Grey reef sharks and hammerheads show up with regularity, and there are also numerous cleaning stations and moray eels.

Kirsty Jayne’s Reef is a long extending reef, lying north to south.  There are two moorings for this reef, and most of the time diving will start from the Christine’s side.  The ridge is narrow and starts descending from 5m/16ft and gradually goes down to 25m/82ft, both sides are fringing walls.  The top of the reef is covered with hard corals, barrel sponges and damselfish.  A short saddle meets with the end of the other ridge.  This then ascends to 17m/55ft.  On the other side are numerous red sea whips that line up in two lines.  At 17m/55ft there are a couple of gorgonian fans and olive whips surrounded by schools of purple anthias – it is a spectacular view.

Coming back to the Christine side, just beside the boat, there is a boundless coral garden.  It is possibly the most attractive point of Kirsty Jayne’s Reef.  It is between 5-15m/16-49ft in depth, and is a very nice area for your safety stop.

The top of Joelle’s Reef sits in approximately 16 meters (52 feet) of water, and the surface of the reef gently slopes down to 25-30 meters (82-100 feet) before it reaches a vertical drop off, except the southern side of the reef that reaches a depth of around 40 meters (130 feet).

Joelle’s is great for those who love big fish, most of the time you can see schools of Barracuda, Big Eye Trevally, Red Pinjalo, Dog Tooth Tuna and Surgeonfish, and on occasion Hawksbill turtles.  For the shark lovers, you can also catch a glimpse of either Grey Reef Sharks or White Tip Sharks.  You will generally see fantastic fish action at Joelle’s when there is at least a small current running.  Around the mooring you can also find three types of anemone fish, Pink, Clarks and Spine-cheek.

Otto’s Point is the steeply descending corner at the north-eastern end of Otto’s Reef.  As the point descends it passes through large numbers of disc shaped mushroom corals at about forty feet/12m, and there is a number of brown bladelike sponges at seventy to eighty feet/20-25m.  There are also sea anemones with pink anemone fish at several depths along the wall.  

Unquestionably, the biggest attraction of the dive is the fish life.  Schools of barracuda, trevally, sea perch, fusiliers, and unicornfish feed in the currents just beyond the reef, joined on occasions by sharks and tuna.  As they round the point they sometimes come so close to the reef that a diver sitting quietly can almost touch them.

Also of interest is the wall south of the point where, at depths of twenty to fifty feet/6-15m, there are numerous ledges, overhangs, and small caves.  The area has a rich growth of many kinds of sponges as well as black corals, reef clams, and ascidians.  Within this encrusting community you can find spider crabs, gobies, and sponge-eating dorid nudibranchs.

Restorf Island offers more diversity within a short distance from the resort than almost any other Walindi dive site. From the sandy beach a diver almost immediately enters the sand flats in which there are large colonies of garden eels, at least four species of shrimp gobies, burrowing gobies, sand anemones, occasional flatheads and flounders, and (in season) the large excavated nests of yellow margin triggerfish.

A little farther to the northeast is a hard coral reef which has some sea anemones occupied by clown anemone fish near the boat mooring and a dense growth of black coral trees and gorgonians and barrel spongers on its deeper side.

Swimming around to the west side of Restorf Island brings a dive where the reef slopes downward in a patchwork of loosely connected bommies, many serving as anchors for gorgonian fans, black coral trees, sea whips, barrel sponges, and elephant ear sponges.  Among these live many species of smaller nudibranchs, shrimp, feather duster worms, and an occasional octopus.

Dense stands of Red Whip Gorgonians, Ellisella sp., give Susan’s Reef a unique aesthetic quality that sets it apart from other Walindi reefs, a feeling which is heightened by clinging tangles of colourful crinoids.  The sea whips are most numerous at the reef’s southern end between seventy-five feet (22m) and fifty-five feet (15m) as it rises up from a saddle that connects the dive site to the much larger Vanessa’s Reef.  Susan’s Reef extends in a northerly direction with a sheer wall on its east side and a sloping garden of hard corals on the west.  At the crest of the connecting saddle, at about eighty feet (25m), are some pale sea fans, and when the current is right a few small sea pens push up through the sand to feed.  

Continuing upward past the sea whips a diver comes upon three large red sea fans.  The deepest, at forty-six feet (14m), is a good place to find the long-nose hawk fish.  Above the thirty-foot (10m) depth, the reef is almost exclusively composed of dense staghorn corals among which are a few sea anemones, which serve as hosts to three different kinds of anemone fish.

Vanessa’s Reef is a submerged shoulder that extends westward from a much larger reef at a depth of fifty to sixty feet/fifteen to eighteen meters.  Its primary attractions are a multitude of large dark red gorgonian sea fans, and farther out on the shoulder, a sponge garden.  Many of the sea fans are eight to ten feet/two to three meters across, or more, and make picturesque backdrops for diver shots.  The fans are also a good place to look for hawk fish, commensal shrimp, and other macro subjects.

The sponge garden includes many bright orange sponge mounds.  Many of the sponges have heaps of crinoids clinging to them, affording the crinoids and elevated position from which to feed in the current.  Near the end of the sponge zone, in 60 feet/18 meters of water, is the boat mooring, beyond which there is a sparser mixture of sponges and sea fans.  On both sides of the shoulder the reef slopes downward to a sandy bottom.  To the north there are additional ridges and ravines, and more sea fans.

Early in the year 2000 a local fisherman found what looked like a man-made object buried in the sand while freediving. He asked the team here at Walindi if we might know what it was, and when we investigated we uncovered the intact

wreck of a Zero fighter.  The wreck of The Zero rests on a sandy bottom in 14 meters (45ft) of water in the shelter of Wangore Bay, north of Walindi.  This World War II Japanese fighter is well presented and almost completely intact, and has been brought to life again by the shrimp, nudibranchs and pipefish that have made this wreck their home – there’s even an anemone populated with pink anemone fish sitting just behind the cockpit.

The plane is believed to have been ditched, as it is perfectly lined up as if coming in to try and find a flat landing spot on it’s return, and the pilot is believed to have survived.  If the Zero is not enough for you, the surrounding bommies are home to yet more critters and nudi’s, a mandarin fish, and a large school of red bass.