What the diving is like
Muck diving inside a large harbour, which is exactly what it sounds like. Ambon Bay is a long drowned inlet that almost cuts the island in two, narrowing partway along its length so that the inner bay exchanges its water slowly. That is why the silt stays where it is and why visibility in the bay is rarely good. The Laha sites run along the shore below the airport road on steep grey silt littered with domestic debris. The bottom is soft, and a fin stroke lifts a cloud that takes minutes to settle, so buoyancy matters more here than on the coarser black sand elsewhere. The structure is whatever has been thrown in — bottles, tyres, rope, netting, fallen branches — and it is on and under that structure that the animals are. Most of the productive ground is shallow, the bay is sheltered enough that current is rarely a factor, and dives are correspondingly long. The jetties are dived day and night. The outer coast is a different kind of diving on the same day, weather permitting: walls, arches, caves and pinnacles on harder ground in clearer water, dived when the sea outside the bay is settled.
The shape of a day
Two or three dives, usually all in the bay unless the sea outside is flat. The boat rides are short, and the bay's sites are strung along a few kilometres of the same shore, so a change of plan between dives costs minutes rather than an hour. Ambon is quieter than Lembeh or Anilao and it is normal to have a site to yourself, which changes how long a guide will spend looking. Night diving in the bay is productive and the entries are as sheltered as the day sites.
Getting there
Pattimura airport, on the same side of the bay as the Laha sites, with connections through Jakarta, Makassar and Manado. It is a longer and less frequent route than the Indonesian destinations further west, and flights are worth booking with slack in them.
When to come
October to April is the usual window. Ambon's seasons run against the pattern of much of Indonesia — the wettest months here are June to August — so a trip planned on general Indonesian advice can land in the wrong half of the year.
Fees and what is not included
No park fees inside the bay. The outer-coast and offshore trips are full-day charters and are charged as such.