Love Rimurimu - Kākāriki (Worser Bay)

Restoration Project

Love Rimurimu - Kākāriki (Worser Bay)

Restoration Objective:

By improving conditions and restoring sites in the harbour with juvenile and adult seaweeds, we hope to set up the right environment for regeneration- helping nature to be a self-sustaining and healthy ecosystem again. These sites will take up carbon, restore habitat and strengthen our marine ecosystem - making it more resilient into the future. Our journey starts with collaboration, learning and innovating.

Site Selection Criteria:

The Kākāriki (Worser Bay) site has been visited regularly by community and school groups as part of the Love Rimurimu project and is closely connected to local community groups. Similar to other sites around Motu Kairangi, Macrocystis pyrifera typically grows at Kākāriki with Ecklonia radiata, Carpophyllum flexuosum, Carpophyllum maschalocarpum and *Undaria pinnatifida* (invasive kelp). The substrate is a mix of boulders and bedrock, intermixed with patches of sand and cobbles. Macrocystis is patchy but once grew at this site in much more abundance.

Cause Of Decline:

Cause of decline: a combination of sedimentation in the harbour, global sea temperatures rising, and overfishing of top predators which has led to an ecosystem imbalance and overabundance of Kina (Sea urchins- which graze heavily on Macrocystis pyrifera).

Key Reasons For Decline:

Climate Change

Imbalance

Sedimentation

Overgrazing

Increased turbidity

Ocean warming

Site Observations:

Observation Date

7th Sep 2023 – 16th Feb 2024

Action Summary:

Trial plant out area was 0.07Ha approx. Methods to come

Lessons Learned:

  1. Observations indicated that several factors may lead to a better start for Kelplings initially:

         - Weather on PO day (UV exposure)
         - Time in transit 
         - Cluster location (those in less UV exposed areas seemed to do better)
  2. Grazing is the main threat to kelpling survivorship initially (however, this has not necessarily been kina (sea urchin) grazing)
  3. High percentage of kelpling loss intially which stabilises after about a month.
  4. Kelplings that were attached to larger rocks (cobbles) when planted out fared better than those attached to smaller ones (pebbles).
  • Note that our sporophytes were grown in a laboratory, and planted out attached to rocks by freedivers.

Project Outcomes:

This project has had constant community involvement and been a collaboration between many different groups leading to positive social outcomes and more publicity for our kelp forests.

Nature of Disturbance:

Data to come
We observed

Key Reasons For Decline:

Unspecified

Indicator Data:

Transplant Info:
Life Stage:Juveniles
Source:Culture