Motukokako Island's wave-carved archway rises 18 metres above the Pacific, wide enough for a catamaran to pass through at high tide. Māori oral tradition names the formation Piercy Island, a navigation landmark used by waka navigators for eight centuries before Captain Cook charted the Bay of Islands in 1769.
The volcanic basalt collapsed inward over millennia, leaving a cathedral vault open to wind and current. Today the passage forms the northern terminus of the bay's 144-island archipelago, a six-nautical-mile voyage from Paihia Wharf.
The bottlenose dolphin population of the inner bay numbers roughly 400 individuals, tracked by the University of Auckland Marine Mammal Research Group since 1989. Pods range between Urupukapuka Island and Cape Brett, feeding on kahawai and yellow-eyed mullet in tidal channels. Sightings peak in austral spring and early summer when juvenile fish school near the surface. Skippers cut engines 50 metres from pods, allowing dolphins to approach on their own terms under Department of Conservation marine mammal protocols established in 1992.
The twin volcanic cones of Waewaetorea Island rise 157 metres to the west, crowned with native pōhutukawa that bloom red each December. Roberton Island holds a protected lagoon where Cook anchored HMS Endeavour for resupply in November 1769. The archipelago's 700 kilometres of coastline host fur seal colonies, little blue penguin nests, and 26 species of seabirds catalogued by Forest & Bird. Gannet diving runs mark schools of pilchard and anchovy from October through March.
Catamarans and mono-hull vessels depart Paihia Wharf eight times daily during peak season, following the western channel past Motumaire Island before turning northeast toward the outer bay. The round voyage spans 60 nautical miles and passes through both sheltered inner waters and open ocean swells beyond Tapeka Point. Skippers narrate Māori history, Treaty of Waitangi context, and marine ecology over VHF commentary. The hole in the rock dolphin cruise from paihia tour remains the bay's most-booked marine excursion, operating year-round with weather-dependent cancellations averaging 12 days per season.
4 hr 30 min
