Sponge Heaven, Milne Bay: Wall Diving and Nudibranch Encounters

Sponge Heaven presents itself as a dramatic vertical drop-off, a geological marvel that begins an astonishing two feet below the surface. As you fin away from the boat, the wall plunges relentlessly, disappearing into the blue abyss, reported to reach depths well beyond 200 feet. This immediate descent into the deep creates an impactful opening to the dive, allowing a sense of scale and adventure to set in almost instantly as you begin your controlled drop along its face.

The topography of Sponge Heaven is characterized by numerous small caverns and overhangs that punctuate the wall's sheer face. These natural alcoves provide intriguing points of exploration, offering a chance to peer into the darkness and discover what creatures might be sheltering within. Each indentation in the rock face casts its own unique shadow play, adding to the visual richness as you glide slowly downwards, observing the changing light and life that adapt to these varying microhabitats.

True to its name, Sponge Heaven is a veritable gallery of sponge diversity. From massive barrel sponges that dominate sections of the wall to delicate, intricate vase and fan sponges, their forms and colours create a vibrant tapestry that covers almost every available surface. These filter feeders are the foundation of a complex ecosystem, providing shelter and sustenance, and are a key element that distinguishes this particular wall dive from others in the region.

Amongst this riot of sponges, the site is a haven for nudibranchs. Keep your eyes peeled for these often-tiny, colourful sea slugs as they meticulously graze across the wall. One of the most sought-after sightings here is the Spanish Dancer (Hexabranchus sanguineus), an impressive nudibranch that can grow quite large and, when disturbed, lives up to its name with graceful, undulating movements as it swims through the water column, particularly captivating on a night dive.

Diving Sponge Heaven offers a captivating experience after sundown. The nocturnal shift brings a different cast of characters to the forefront, and the vibrant colours of the sponges and nudibranchs truly pop under the beam of your dive light. Encountering a Spanish Dancer in full display during a night dive against the backdrop of the darkened wall is an experience that lingers long after you surface, adding another dimension to this already rich dive site.