Interview ~ Our warming Moana-nui-a-Kiwa
Earlier in the month Sue Fitchett interviewed Lindsay Jeffs - here’s their story
As swimmers and experts confirm, this summer has seen increasing, sustained and in some places record warm temperatures in the ocean. Dire predictions are being made about e.g. krill population decline in the Southern Ocean and its impact on our larger marine species.
The ‘whys’, ‘wherefores’ and local ‘consequences’ of this phenomenon are explored by Sue Fitchett in an interview with Lindsay Jeffs (Carbon Neutral Waiheke and WMP Steering group).
SF Why do you think the sea is significantly warmer than normal this summer?
LJ The primary driver is climate change with its associated increasing acidification of the ocean coupled with other ‘land to sea’ pollution.
SF What are the consequences and long term impacts of sustained and increasing warming of the ocean on the flora and fauna within Tikapa Moana?
LJ Biomass and species diversity will reduce. More invasive species will appear. Very worryingly will be the reduced ability of all oceans to absorb carbon. Oceans have acted historically as carbon sinks for the planet. Scientists are still trying to quantify this effect entirely. A tipping point will be reached when this whole process will speed up.
SF Food sources for species such as korora are already under threat in Tīkapa Moana (Hauraki Gulf) and other coastal areas, particularly the Nth Island. How will some of these consequences affect future food sources?
LJ Some food sources will disappear or move into colder parts of the oceans for their survival. As you know kororā are not only inshore feeders but their diet includes small crustaceans which will suffer from shell loss due to increasing ocean acidification.
SF What actions can the motu and the Waiheke Marine Project take to mitigate climate change instigated temperature changes in Tīkapa moana and the seas around Aotearoa?
LJ We, including, Waiheke Marine Project, need to do more to put the importance of the carbon sequestering role of the ocean onto people’s, agencies and the Governments radar. NGO’s like WRT have been doing great work in relation to land based wetlands but examples of other actions and projects include the mapping of existing and potential inter-tidal areas around the island’s coastline (and elsewhere in the Hauraki Gulf). The WMP aligned Kelp regeneration project is a good start in terms of mitigation actions. Other carbon sequestering opportunities would include increasing the percentage of coastal salt-marsh and mangroves. Mangroves make up only 1% of Waiheke’s coastal habitats and saltmarsh and seagrass make up even less. Such projects would increase biomass as well as adding to carbon sequestering. Dr Jo Russell, who analysed the role of Northland mangroves, salt marshes and seagrass in sequestering carbon, found that around 11% of the estimated 1,100,000-1,300.000 tonnes of carbon emitted by Northlanders each year was sequestered by these inter-tidal habitats. This is higher than carbon sink rates oceans are, generally, considered to have. Such habitats absorb 3 or 4 times more carbon than tropical rain forests. All future wetland and mangrove reclamation should be banned throughout Tīkapa Moana. WMP could be an advocate and lobbyist to e.g. the Climate Commission and Auckland Council to consider and include in recommendations and strategic plans the importance of ‘blue carbon’ assessments and initiatives (in reference to mangroves, algae, salt marshes and seagrasses restoration, protection and enhancement). Australia is ahead of Aotearoa with their ‘blue carbon’ initiatives including letting the sea ‘back in’ to increase coastal swampy areas.
By Sue Fitchett ~ 2021