Pegasus Bay, earlier known as Cook's Mistake, is a bay on the east coast of the South Island of New Zealand, to the north of Banks Peninsula. Toponymy Pegasus Bay takes its name from the brig Pegasus, a sealing ship that was sailing from Hobart to London via the sealing islands and was surveying this part of the South Island in 1809. Attempting to sail into Gore's Bay shown on Captain Cook's map between the supposed Island that Cook had named after Banks, the crew discovered a mistake in Cook's chart and found the island was a peninsula connected to the rest of the South Island mainland by a low-lying isthmus. Fortunately they discovered this before trying to pass between the supposed island and the mainland before dark while approaching from the north and were still in about of water. Captain Chace (or Chase) and his first officer William Stewart, who had also surveyed Stewart Island on the same journey, were reported in the Oriental Navigator in 1816. Charts made of this part of New Zealand from the 1809 survey give the names Cook's Mistake or Pegasus Bay to this large bay. Maori do not divide this part of the coast in the same way, so there is no equivalent Maori name. However, the sandy beach on the shoreline between the Ashley River and Avon/Heathcote Estuary is known as Kairaki (which is an ancient name of unknown meaning for the Pacific). While a fishing ground to the east of Pegasus Bay is known as Komaka a Te KaiKai a Waro meaning the foodstore belonging to KaiKai a Waro. Geography Pegasus Bay lies on the east coast of the South Island of New Zealand, between the Motunau River and Motunau Island in the north and Banks Peninsula in the south. The bay is nearly across and deep, with of water that gradually shoals to about or about from shore. The northern part of the coast are mostly cliffs, with stony or sandy beaches at low tide. The bay has a sandy beach that runs for about from about the Waipara River mouth to the Christchurch suburbs of Sumner and Scarborough on Banks Peninsula. Rivers Rivers flowing into Pegasus Bay, from north to south, are: Motunau River Waipara River Ashley River / Rakahuri Waimakariri River Avon River and Heathcote River via the Avon Heathcote Estuary Fauna Other than dolphins including the endemic,