Shark Gutters, also known locally as Grey Nurse Gutters, occupies a sliced channel on the northern side of South Solitary Island between Birdie Island and a neighbouring rock, historically one of the more consistently productive grey nurse shark sites in the whole marine park. A large boulder wedged between the gutter's two walls creates a genuine swim-through adventure at a shallow, forgiving 12 m mooring depth, making this one of the more approachable shark encounters at South Solitary Island for Open Water-certified divers rather than requiring the deeper, more current-exposed profile of Manta Arch. In years past this gutter has held substantial numbers of resting grey nurse sharks, and while population numbers here fluctuate with the wider aggregation patterns tracked across the marine park, it remains one of the go-to spots for divers hoping for an encounter without the stronger current typical of the more exposed north-eastern moorings.

Schooling kingfish, silver trevally, jewfish, pomfreds and bullseyes move through the gutter in numbers, and the walls themselves are decorated with black coral, tarwhine and resident blue groper and wrasse species, giving the site plenty to offer even when the sharks are elsewhere. The swim-through nature of the site means divers need to move through in single file without crowding the gutter, both out of courtesy to other divers on a busy day and to avoid disturbing any sharks resting in the passage. Surge can build through the gutter in a decent swell, since the channel effectively funnels water movement, but on a calm day this is a comfortable, moderate-depth dive that combines genuine swim-through topography with one of the more reliable historical grey nurse shark track records in the park.

Jetty Dive Centre departs from a public floating pontoon wharf on the Coffs Harbour boat harbour, opposite the Attitude Burgers building — check in first at 398 Harbour Drive, Coffs Harbour. It is roughly a 30-40 minute run out to South Solitary Island, 8 km offshore, in the dive centre's RIBs. Private boats launch at the Coffs Harbour public boat ramp inside the breakwall and follow the same course out past the harbour entrance.

South Solitary Island sits in open water 8 km off Coffs Harbour and is exposed to swell from the north-east through south-east; Jetty Dive Centre generally wants under about 1.5-2 m swell to run the outer moorings comfortably, switching to the more sheltered Split Solitary Island (only 20 minutes out) on rougher days. Visibility here is usually the best in the marine park given the distance from any river mouth, and the site's position at the boundary of tropical and temperate water means conditions can change quickly with wind shift. Summer (Nov-Apr) water is warmed by the East Australian Current to up to 26°C, bringing tropical fish, manta rays and, from December, leopard sharks; winter (May-Oct) cools to about 18°C but often gives calmer seas, giant cuttlefish and the peak grey nurse shark season (Jun-Nov, sometimes 30-60+ sharks on Manta Arch).

Humpback whales migrate past between April and November, peaking June-August northbound and September-November southbound. Currents can run strongly on the exposed north-eastern moorings (Manta Arch, Shark Gutters) and are much gentler on the sheltered north-western wall.

Descend the mooring into the gutter mouth at 12 m, move slowly through the swim-through past the wedged boulder without blocking the passage, and work the walls either side for schooling fish and black coral before ascending.

Jetty Dive Centre (Coffs Harbour) runs South Solitary Island most days conditions allow, typically a double boat dive; it is the flagship site for the only major dive operator based in Coffs Harbour.