Using species inventories to guide the selection of optimal locations for marine reserves

Abstract

Globally, there is a trend of decreasing marine biodiversity. To mitigate biodiversity loss due to anthropogenic impacts establishing marine reserves is considered an effective way to safeguard ecosystems. This aligns with global conservation goals based on the 2010 Aichi Targets which aim to have marine protected areas covering 10% of coastal waters by 2020. Currently, New Zealand has 44 Marine Reserves established throughout the territorial sea. To meet the Aichi Targets, New Zealand must expand the current Marine Reserve network to locations that represent nation-wide biodiversity. Determining locations for conservation priority requires having an understanding of the biodiversity currently protected within the network, and then identifying areas that would increase this protection. A database of species protected within current Marine Reserve boundaries was created based on species presence data. This database of species assemblages was analysed to investigate biodiversity facets and patterns within the network. Areas of conservation interest were assessed in the context of the entire network to determine whether they would complement the current Marine Reserves by offering an increase in biodiversity protection. From this analysis, two candidate reserves at the Mokohinau Islands and Doubtful Sound (Bauza Island) were shown to offer complementary species assemblages. The method used in this analysis can provide stakeholders with a tool for investigating candidate locations for future reserves based on ecological data. To identify other areas for conservation prioritization, a gap analysis of current Marine Reserve coverage of nationwide biodiversity was conducted. The results revealed that many species present in the Exclusive Economic Zone (EEZ) are not currently represented in the Marine Reserve network, which appears to be associated with the lack of open ocean reserves in New Zealand. Biodiversity patterns within the EEZ were investigated to provide environmental context to species assemblage discrepancies. The addition of this information to the MPA planning process could provide conclusive results as to whether implementing a new reserve at any location will assist New Zealand in achieving our Aichi biodiversity targets by 2020. In turn, this could increase the sustainability of New Zealand's marine management.