Hirokawa Maru (Bonegi 1), Honiara, Solomon Islands

Site Overview
Site Type: Ship Wreck and Reef
Depth: Top: 5M Bottom: 50M
Location: Off Bonegi Beach near Bonegi Creek, west of Honiara, Solomon Islands

The Hirokawa Maru is known as ‘Bonegi 1’ or even ‘B1’ – being the deeper of two shore-wreck dives close to the  Bonegi Creek – a truck ride from Honiara on Solomons Guadalcanal.

The Hirokawa Maru was one of 11 Japanese transports attacked on their way to Guadalcanal on the 14 November 1942. Four ships made it through the initial attack, but were discovered at dawn on 15 November by the Americans close to the beach north of Henderson Field and they were then bombarded from land and sea.

The 156m long Hirokawa Maru was originally stranded upright ashore, but over time, weathering various storms, quakes and the actions of salvagers, the ship now lies on her port side with the remains of her bow in about 5 m and her stern in 60 m.

Silhouette with seafan and diver at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

There is plenty to explore, and you would be wise to do at least one orientation dive with an experienced guide. Much of the superstructure and the kingposts that remain are covered in hard corals, which continue down well below the 20m mark.

Hard corals growing all the way down at Bonegi 1 diving Honiara in the Solomon Islands by Diveplanit

Sections of the deck are open in parts and (with an experienced guide) you can swim through some of these. There are numerous large gorgonian sea fans which grow out from the side of the wreck – some filling the space once closed by solid metal plate.

Seafan fills a gap in the hull at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

Though the wreck is impressive in size, it’s ‘shape’ is more confusing. Apart from what is obviously a large (now flat) hull, and kingposts, much of the wreck is now so encrusted with coral it’s hard to see what might have been what.

Divers on the wreck at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

From my perspective, a wreck evolving into an artificial reef is not a bad thing as it attracts a wealth of marine life. You’ll find snapper, butterflies, sweetlips, batfish and lionfish to name but a few, as well as the usually basslets and fusiliers.

Coral landscape with small reef fish at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

Most of the coral is actually in very good condition, and like on many of the wrecks in the Solomons, some of the corals have grown to quite large sizes.

Single cabbage coral at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

It’s the kind of wreck you can dive a number of times focussing on different aspects each time.

Stoney coral on wreck with diver at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

My dive profile has me descending steadily to 34m over the first 15 minutes, then back up to 15m over the next 15 minutes – the rest of the hour dive was spent between 9 and 5m.

Brain coral on the end of a beam at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

I was lucky enough to spot this little cleaning station in the 5 m shallows which seemed to be reserved exclusively for Damsels and Pullers. I must have spent 10 minutes in just that spot; as eventually the fish grew accustomed to my presence and carried on with their grooming rituals.

Yellow Puller being cleaned around the eye at Bonegi 1 diving Guadalcanal. Scuba holiday travel planning for Solomon Islands - where, who and how

The Hirokawa Maru is known as ‘Bonegi 1’ or even ‘B1’ – being the deeper of two shore-wreck dives from the same stretch of beach.