Hydrology of Hauraki Gulf
- N.Z. Oceanographic Institute, Wellington.
Most of the published data concerning the Hauraki Gulf are confined to surface temperatures (Cassie, 1956; Dellow, 1955; Marine Department, 1938; Skerman, 1958).
The only records of salinity are by Fuller ( 1953) and of subsurface temperature by Cassie (1957). I have collated the published data with unpublished data from various sources and it is possible to present a reasonably representative picture of conditions in the Gulf both for summer and winter. While my interpretation may seem rather a drastic oversimplification to the hydrologist, I feel that some interpretation is better than none, and that it will be quite adequate for the purposes of the ecologist. I will consider only the outer Gulf (north of an east-west line passing through the northern extremity of Waiheke). The inner Gulf, Firth of Thames and Waitemata Harbour will obviously be more heterogeneous in character, depending On the influence of various freshwater sources. In general, salinities will be lower, particularly in winter, and temperatures will be several degrees higher in summer and lower in winter.