A raphidophyte-dominated phytoplankton bloom extended discontinuously along the northeastern coastline of New Zealand, from Bream Tail, north of Leigh, to the western coast of the Coromandel Peninsula from late August until December 1992. The bloom was associated with an "El-Niño" phase of the Southern Oscillation, resulting in unusually cold sea temperatures. The dominant bloom species in the north was Fibrocapsa japonica and in the south Heterosigma akashiwo. Associated species included the coccolithophorid Gephyrocapsa oceanica and the naked form of the silicoflagellate Dictyocha speculum. By December, numbers of the armoured form of D. speculum had increased, as those of raphidophytes and coccolithophorids declined. Bioassays to test for shellfish biotoxins were negative and Artemia salina bioassays, indicators of ichthyotoxicity, were negative except for Heterosigma akashiwo cultures, isolated from Coromandel water samples. M93035

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New Zealand established its first no-take marine reserve more than 25 years ago. Twenty notake marine reserves have now been created, although few of these are considered comparable. We considered whether existing conceptual models of population and community structure based only on data from exploited systems lack the baseline information of natural states necessary to make accurate predictions for new reserves. Three of the oldest and best-studied reserves are situated on the northeastern coast of New Zealand. These reserves are considered broadly comparable replicates, and research has shown the recovery of previously exploited predator populations and the reestablishment of trophic controls over community structure and productivity. None of the major changes was predicted when the reserves were created. All the observations from and experimental tests of hypotheses in these three ecologically comparable reserves have provided predictive models for future reserves. Recent surveys in newly created reserves, however, suggest that these models are bioregion and habitat specific. In these new reserves the recovery of previously exploited predators was predicted but did not always occur. Where trends were correctly predicted, the speed and amplitude of the changes were not accurately predicted. Research in New Zealand suggests that it is not yet possible to predict explicit outcomes for newly created reserves and less possible to predict detailed results for systems of reserves. Results from a representative system of reserves, including all major habitats within all bioregions and broadly comparable reserves, are needed. Such a system will enable the range and variety of natural ecosystem dynamics to be investigated and provide the controls necessary to measure the effects of exploitation. Key Words: ecosystem change, effects of fishing, trophic cascade Investigación Ecológica Marina en Nueva Zelanda: Desarrollo de Modelos Predictivos a través del Estudio de Reservas Marinas sin CapturaResumen: Nueva Zelanda estableció su primera reserve marina sin captura hace más de 25 años. A la fecha se han creado 21 reservas marinas sin captura, aunque algunas cuantas son consideradas comparables. Consideramos si los actuales modelos conceptuales de la estructura de poblaciones y comunidades basados sólo en datos de sistemas explotados carecen de la información básica de sistemas naturales necesaria para hacer predicciones precisas para reservas nuevas. Tres de las reservas más antiguas y mejor estudiadas están situadas en la costa nororiental de Nueva Zelanda. Estas reservas son consideradas réplicas ampliamente comparables, e investigaciones han mostrado la recuperación de poblaciones de depredadores explotadas previamente y el restablecimiento de controles tróficos sobre la estructura y productividad de la comunidad. Ninguno de los cambios mayores fue pronosticado cuando las reservas fueron creadas. Todas las pruebas experimentales de hipótesis en estas tres reservas ecológicamente comparables han proporcionado modelos pre...

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