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juvenile snapper with the aim of releasing them into the Tasman Bay fishery. During this period there was also strong commercial focus and commercial interest in the other research projects, which included the rearing of rock lobsters, Bluff oysters and surf clams, as well as feeding trials with phyllosoma and juvenile lobsters and with two species of abalone. There was also a focus on technology transfer by such means as the renowned paua farming and hatchery technology courses (run regularly from 1992-1998) and the publication of Aquaculture Update (in 29 issues from 1992-2001). The algal culture unit was always a key component of the work at Mahanga Bay and under Sarah Allen's control the unit also housed, in a biosecure situation, the country's main collection of microalgal species. During the 1990s the algal unit was running at full capacity to supply the very considerable food requirements of the oyster, mussel, paua, lobster and snapper projects, including microalgae for production of rotifer and brine shrimp which in turn were food for juvenile snapper. Reassessment of research directions during the 1990s decade saw the rock lobster work focussed both on rearing juveniles through to market size - initially in a land-based farm, but subsequently and more successfully in seacages and on the potential for rearing the second commercially important lobster species, the packhorse lobster Jasus verreauxi. Finfish research shifted from snapper to turbot and seahorse, with flatfish seen as having potential for land-based farming (during a moratorium on new marine licences) and seahorses being a high value product, extensively over-exploited in overseas fisheries. Before the end of the decade a fourth finfish species was studied at Mahanga Bay, when juvenile yellowtail kingfish Seriola lalandi were shown to have a growth rate sufficiently rapid to indicate that a harvestable product would be possible after six months or that after one year the average weight could be three kilogrammes. Philip Heath became the Manager of the NIWA Mahanga Bay Aquaculture Research Facility in early 2002, following the retirement of Len Tong in 1999. By this time the seahorse research under Chris Woods, was into its third generation of juveniles. The work aimed to explore culture techniques and practices that will increase the economic feasibility of culturing seahorses in New Zealand, principally by determining ways to wean them off live foods. Phil James' project using waste mussels for feeding rock lobsters had indicated that sea-based culture could greatly increase the profitability of lobster farming as well as diversify existing mussel farming operations, whilst Graeme Moss had shown that, with its shorter larval life and faster juvenile growth, the packhorse species is a more viable candidate for lobster farming than the red rock lobster. Paua research at Mahanga Bay was headed in two new directions. One was the development of a selective breeding programme, requiring the on-growing of some 20 "families" of seed at paua farms around the country. The other was the establishment of a seed production unit to supply new paua farmers, which required the construction of the prominently sited 15m by 9m plastic-covered greenhouse to accommodate the seed rearing tanks. Phil Heath brought his experience and interest in recirculation technology to bear on several of the projects, but most notably on paua, such that within three years technology transfer had enabled Mahanga Bay experience and skills to assist in the development of a commercial paua farm based fully on recirculation technology. The last few years at Mahanga Bay typify the range and Mahanga Bay Shellfish Hatchery, Miramar, Wellington variety of work that has been undertaken at NIWA's cool water aquaculture research facility, with ongoing studies on paua using recirculation technology, investigation of potential new aquaculture species such as butterfish, groper, sea urchins, sea cucumbers and seaweed, and related projects such as diet development for these potential new species. Activities not specifically aimed at aquaculture which have also been conducted at Mahanga Bay over the years, most notable perhaps being work on giant squid in the late 1990s, have continued in the projects on anti-fouling materials, which make use of the rafts in the bay, and on the impact of climate change on shellfish, which uses the controlled temperature rooms to study Antarctic clams held at -1 degree Celsius. Together with the uniqueness of its somewhat remote location and the consistently high quality of its seawater supply, Mahanga Bay has had the advantage of an extraordinary range of people who have worked, studied and visited the facility over its almost 40 years of operation. There was only ever a small number of permanent staff but they benefitted from frequent injections of skill, expertise and even personality from the many people who worked alongside the staff. These included scientists from the same and other organisations, staff and students from universities, employees of companies using the facilities, and numerous visitors from around New Zealand and overseas. A list compiled for the definitive publication on Mahanga Bay is the source of many quotations in this article and gives the names of 113 people who worked at Mahanga Bay from 1974 to 2008. There is also a list comprising 14 finfish, four crustacean shellfish, 27 molluscan shellfish, three echinoderms, four sponges and eight seaweeds, as well as maybe 50 different species of microalgae that were worked on during the same period. Mahanga Bay has arguably the best, the most functional and the most reliable cool water seawater system operational in New Zealand. It remains to be seen whether it has a further role to play as an aquaculture or aquarium facility or whether its closure brings to an end this chapter in the history of aquaculture in New Zealand. Bob Hickman is a retired MAF and NIWA aquaculture research scientist and author of "Mahanga Bay. The life history of an aquaculture research centre." NIWA Information Series No 71., 2009, ISSN 1174-264X MAY/JUNE 2013 ■ NZ AQUACULTURE ■ 7