New Zealand Spain s Antipodes

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1 Alastair Macfarlane

2 Outline Locating New Zealand the Antipodes of Spain The new-found continent of Zelandia and its oceanic impact Climate dynamics in the South Pacific New Zealand s fisheries Actual and potential temperature changes Resilience and acidification Conclusions for New Zealand fisheries

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4 New Zealand Spain s Antipodes Located/isolated in the mid-latitudes of the Pacific Surrounded by ocean, no moderating Gulf Stream or continental land mass Temperate coastal waters and sub-antarctic deep ocean High biodiversity but relatively low fisheries productivity

5 Zealandia the new continent The NZ archipelago is the above sea-level evidence of a sunk continent a Gondwanaland remnant. The sunken continent affects sea currents round NZ, accentuating dynamic mixing of subtropical and sub- Antarctic waters

6 Zelandia the new continent

7 South Pacific Climate Dynamics Interdecadal Pacific Oscillation

8 South Pacific Climate Dynamics

9 New Zealand s Fisheries 11 million sqkm EEZ 5 th largest; Considerable biodiversity but moderate productivity; Quota management system includes 100 species in 680 stocks; 80% of catch is from EEZ sub-antarctic stocks Heavy export reliance NZ$1.8billion (EUR1.2 billion)

10 Actual and Potential Changes NZ s commercial fisheries mostly developed in last 50 years very little historic data to recognise trends Experiencing only second inter-decadal oscillation. Impacts of ENSO cycle are poorly understood Australian east coast climate change experience is not obviously being shared in NZ A gradual warming is likely to favour coastal fisheries, but impact on deeper water species is less clear Sub-Antarctic current may act as a barrier to commercially important orange roughy, hoki and squid moving south

11 Hoki Principal ground fish fishery TACC 150,000 tonnes Population est. 1.2 billion plus 1.2 billion juveniles TACC set to harevest 10% adult population Actual catch in 2015/16 136,719 tonnes Export sales NZ$213.2 million (EUR138 million) Main Markets: EU 36%, Australia 25%, China 22%, Japan 6.4%, Others 11% Significant recruitment decline at turn of century, led to significant TACC cuts and industry rationalisation

12 Squid High TACC Trawl TACC 77,100 tonnes Highly variable catch due to seasonal variances and recent access rules. 2015/16 42,000 tonnes. 2016/17 13,000 tonnes Impossible to estimate population in advance of season Export sales 2016 NZ$117 million (EUR 76 million) Main markets: EU 38%, China 35% Similar north to south fishing pattern through season as in South-west Atlantic Abundance cycles opposite to South-west Atlantic

13 Resilience and Acidification Recent lab study of greenshell mussels demonstrates genetic capacity to adapt to seawater PH change Lower PH may favour phyto-plankton over zoo-plankton

14 Conclusion for NZ Fisheries NZ fisheries have considerable bio-diversity and are adapted to existing decadal and inter-decadal variances; But NZ commercial fisheries experience is mainly in last 50 years little knowledge of previous responses of key species to climate-related stresses; It is likely that NZ s oceanic isolation will mute the impact of climate change, but the effects may carry on longer as the ocean stores and releases heat over much longer periods than land; Genetic diversity in molluscan genomes may cope better than feared as the PH of the ocean becomes less alkaline.

15 Conclusion for NZ Fisheries Resilience to environmental change is enhanced by conservative management settings NZ rights-based Quota Management System operates on conservative harvest control rules. 97% of stock levels are at, or above, limit controls Identifying underlying trends through the chaos of other climate cycles requires time Commercial stakeholders have a direct interest in safeguarding their quota rights through conservative harvest decision making