Marine Ecological Research in New Zealand: Developing Predictive Models through the Study of No‐Take Marine Reserves

Abstract

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...

Exploited reefs protected from fishing transform over decades into conservation features otherwise absent from seascapes

“…At Leigh, increased populations of lobsters and large fishes reduced sea urchin populations, which ultimately led to major changes in macroalgal cover across the MPA seascape 25 years later. Increased macroalgal cover in turn transformed the regional mosaic of habitat types, which then generated additional responses amongst other grazing invertebrate groups (Shears and Babcock 2003), a fourth order interaction (Langlois and Ballantine 2005). Changing algal cover also likely affects populations of fish and sessile invertebrate species that are closely associated with vegetated habitats (Ling 2008).…”

Fishing industry and related perspectives on the issues raised by no-take marine protected area proposals

“…The evaluations, however, reveal that the biodiversity benefits were limited in their degree and extent, as areas were conferred only partial and/or temporary protection, in that the zonation scheme provides for periodic trawling and, at the most restrictive, zones where only static nets and pots can be deployed. Whilst the direct impacts of static gears on benthic habitats are much less than those of towed gears, such impacts can be significant and there are also trophic and structural cascade effects related to the harvesting of certain species that can indirectly but significantly affect the structure and diversity of benthic habitats, as well as associated pelagic populations [28,34,35]. Proponents of NTMPAs therefore argue that full biodiversity restoration can only be achieved by full and permanent protection [28].…”

Leigh Marine Laboratory contributions to marine conservation

“…Research at LML supplied Bill with a stream of new results with which to argue and promote the advantages of marine reserves as conservation tools. Bill's thinking has in many ways been ahead of its time, and his work has helped not only to promote marine conservation and scientific research and thinking around marine reserves (Ballantine 1989(Ballantine , 1991aLanglois & Ballantine 2005;Ballantine & Langlois 2008) but to raise public awareness of the marine environment in general. Bill was awarded a Goldman Environmental Prize in recognition of his lifetime achievements in this field in 1996.…”