Published in Divelog Australasia April 2024

by Nigel Marsh and Helen Rose

There is a sign on the coast of Ambon that reads – AMBON CITY OF MUSIC. This large Indonesian city is more than likely home to some amazing musical talent, but we were quite surprised that some enterprising diver hasn’t modified this sign to read – AMBON CITY OF MUCK – as the city is home to some of the most amazing muck diving sites in Asia.

Ambon is located in the Maluku Islands in eastern Indonesia, a group of islands that are still commonly called the Spice Islands. Ambon is quite a large city and spreads around both sides of the sheltered waters of Amboyna Bay. The black sand beaches of this bay are not very picturesque, as most are littered with rubbish, rusty old ships and other debris. However, the black sand continues underwater, forming the perfect habitat for weird and wonderful critters and some of the best muck diving sites in Indonesia.

Only a handful of dive operators are found at Ambon, with Spice Island Divers one of the best dive resorts in the area. Located on the coast, only minutes from the airport, they offer accommodation in either seafront villas or garden rooms. Facilities include a large restaurant and bar, a camera setup room and a well laid-out dive centre with plenty of washing and drying areas. They operate four dive boats and offer four daily dives to the best muck sites in the area.

Arriving at the resort at noon gave us time to settle into our room, sort out the camera and dive gear before the afternoon dive at 3pm, and also enjoy the very filling three-course lunch without having to rush. A package deal with Spice Island Divers includes all meals, and these are a great mix of Asian and western dishes.

In the afternoon we strolled down to the dive centre, met our local guide Haris and boarded our dive boat. Spice Island Divers have around 50 muck diving sites they visit in Amboyna Bay, and occasionally venture outside the bay to explore reef sites. With our stay only being for five nights we were happy to concentrate on the muck sites that have made this area famous.


Our first muck site was only minutes from the resort, the wonderful Laha 2. This site is typical of the area, with a sandy/rubble slope dotted with patches of seaweed and coral. Going no deeper than 24m, in the 12m visibility we fanned out to look for critters.

We quickly spotted snowflake, white-eyed and fimbriated morays, lots of compressed and blackspot tobies, lionfish, porcupinefish, small cuttlefish, mantis shrimps, flasher wrasse, razorfish and stonefish. Haris showed us the resident pair of harlequin shrimps munching on a blue seastar and quite a few Coleman shrimps and zebra crabs on their fire urchin homes. We also found jawfish, nudibranchs, fingered dragonets, demon stingers and several sawblade shrimps clinging to algae.

It was a great first dive, however, we were saddened by the amount of rubbish, it was everywhere. There were plastic bags and other rubbish on the bottom, in mid water and on the surface. This rubbish was evident on every dive. The Indonesian Government really needs to get its act together and clean up the environment and ban single use plastic bags, as other countries like the Philippines have started to do.

After sunset we jumped on the dive boat once again for a night dive at nearby Air Manus Jetty. This sandy slope was completely covered in nocturnal critters. We encountered several longarm octopus and a small coconut octopus, and were very happy to find several starry night octopus on the prowl, as these are a rarely seen species. There were plenty of other cephalopods, including broadclub and flamboyant cuttlefish and several tiny bobtail squid.


Our torches spotlighted sawblade shrimps, robust and ornate ghostpipefish, hunting morays, scorpionfish, crabs, shrimps, prawns, flatworms, squat lobsters, porcelain crabs and a baby warty frogfish. There were actually a few juvenile fish to be seen, with a big highlight being a baby thornback cowfish only 1cm long! There were also nudibranchs and sea slugs everywhere, including a few species we had never seen before.

The next morning we crossed Amboyna Bay to dive Batu Labang. This side of the bay is the best location to find one of Ambon’s most famous critters – the psychedelic frogfish. This strangely patterned frogfish was one of the main critters that lured us to Ambon. Unfortunately, encounters are unpredictable, and the dive crew informed us that it had been three months since they had last seen one.

Batu Labang was another sandy slope with patches of seaweed that had no shortage of critters. We encountered Napolean snake eels, Pegasus sea moths, a dozen robust and ornate ghostpipefish, numerous small broadclub cuttlefish and a very photogenic longhorn cowfish. Haris also pointed out xeno crabs, orangutan crabs, bristle worms, mantis shrimps and a variety of nudibranchs.

After morning tea, we dived the nearby Tirta Point. This slope was even more packed with critters with us photographing common and thorny seahorses, painted and hairy frogfish, a pygmy pipehorse, bentstick pipefish and ghostpipefish. The main highlights from this site were two cute Ambon scorpionfish and three mimic octopus.

After lunch we dived Ambon’s most famous muck site – Twilight Zone. This site could be called the scrap yard, as derelict boats line the shore and there is a huge pile of rubbish at the end of the bay. Even with all this debris it hosts an amazing array of critters.


We started our dive under the stern of a derelict ship, in only 1m of water. Here Haris searched the soft corals, hydroids and sponges that grow on its hull searching for frogfish. This search proved very rewarding as he found four resident freckled frogfish, each a different colour. We then explored the sand and rubble, finding Napoleon snake eels, reptilian snake eels, morays, sea snakes, stonefish, cowfish, tobies and a pretty pair of harlequin shrimps. A surprising highlight was a group of female bigfin reef squid laying their eggs on the bottom debris.

The next morning, we did our first dive at Kampung Baru. The morning conditions were usually the best, with 15m visibility and calm seas. The dive got off to a great start with a banded snake eel out in the open just below the boat. We then explored the sand and rubble slope, seeing morays, painted frogfish, cowfish, leaf scorpionfish, ghostpipefish, seahorses, squid and cuttlefish. Under one ledge we found a group of three Morrison dragonets and were delighted by the number of boxfish, including black, spotted and a rare rhino boxfish. However, the stars of this site were two weedy scorpionfish, a purple one and an orange and pink paddle-flap variety.

With the great visibility we did a return to Twilight Zone after some morning tea. Considering we had only dived the site the day before, we didn’t expect to see much different. But day-to-day muck sites critters can completely change. Searching the slope, we found whitefaced waspfish, box crabs, elbow crabs, sea moths, seahorses, mantis shrimps, snake eels and hairy frogfish. Haris also found a very rare algae octopus. We had seen a number of these strange octopus in the Philippines seven years ago, but hadn’t seen one since. Haris then topped this by finding two boxer crabs with their sea anemone boxing gloves hiding under the rubble. A close inspection of both crabs revealed they were carrying eggs attached to their legs. We made sure these delicate little crabs were safely put back into hiding before a hungry fish made a meal out of them!

Our afternoon dive at Rhino City was also excellent with more frogfish, ghostpipefish, jawfish, mantis shrimps, cowfish, cuttlefish and sea moths. A highlight of this site were two solar-powered nudibranchs crawling over the sand. We ended the day with another night dive at the Air Manus Jetty seeing pretty much the same species we had seen on the last night dive, and also found a rare nago snakemoray, a first for us.


The next morning, we explored a different section of Kampung Baru. This site was overloaded with morays that squeeze into every available hole, sometimes five or more crammed in together. We noted white-eyed, bartailed, highfin, drab, snowflake and fimbriated. We also saw a yellow-lipped sea krait and its mimic, the banded snake eel. Haris pointed out juvenile warty and painted frogfish, a cute common seahorse, nudibranchs, longarm octopus and cuttlefish.

Our mid-morning dive saw us return to Laha 2 to explore more of the sand and seaweed at this site. Boxfish, cowfish, tobies, nudies, mantis shrimps were everywhere. We also found several juvenile black-coloured ribbon eels and two very rare banded mud morays out on patrol. There was even a group of bluespotted maskrays in one sand patch. The highlight of this dive were two spectacular Honshu pipefish under a ledge. These lovely blue and yellow striped fish were wonderful to watch as they slowly danced around each other.

That afternoon we planned to do Air Manus Tower, but when we pulled up the water was brown, from what looked like runoff from the nearby river. We turned the boat around and instead redid Twilight Zone.

That night we signed up for the blackwater dive. The deep water in Amboyna Bay is a good site for blackwater dives, but with it also a very busy waterway, the crew have to be very careful where they do this. We headed several kilometres into the bay then dropped ropes and lights. Hanging under the boat we saw small fish, sea jellies and comb jellies, and plenty of plastic bags. Unfortunately, the unusual critters eluded us this night.

The next morning we did our last dive at Kampung Baru. This was another great muck dive, we saw the purple weedy scorpionfish again and a school of feeding mouth mackerel. Other highlight from this dive included a wonderpus, an oriental flying gurnard and many cute black-patch triggerfish.

We had a great time at Ambon with Spice Island Divers and only scratched the surface of the great muck dives in the area. We know we will be back as there are many more muck sites to explore and many more muck critters to be seen, including the very elusive psychedelic frogfish.