The Regional Council are monitoring the three areas that make up the Motiti Protection Area as well as the wider Motiti Natural Environment Management Area. The objective of this monitoring is to determine if the protections put in place by the court are achieving the desired biodiversity outcomes. Are the Marine Protection Areas working?
The BOPRC Science Plan sets down priority work areas, including Toitū te Takutai moana – Marine and Coastal, which includes a number of priority areas in relation to the Motiti Protection Area:
- Develop cultural health indicators (in conjunction with tangata whenua specialist advisory group) to assist with and work with tangata whenua on effective implementation.
- Understanding present and future threats to coastal ecosystems and biodiversity values with a strong focus on climate change, and development of management options.
- Understanding and monitoring ecosystem and biodiversity values in the marine coastal zone to assess potential adverse impacts by fishing activities.
The science plan also identifies resourcing, capability and relationships as requirements to deliver this work. It sets out the importance of working with research providers, local iwi and to include external specialist expertise when needed for areas such as broadscale habitat mapping.
During the Environment Court hearings (see final decision here) a wide range of scientific and cultural knowledge was shared with the courts showing the decline of environmental and cultural health in the Motiti area. Traditional mātauranga Māori knowledge held by tangata whenua represents a longer timeframe of changes observed in the marine environment, compared to the current day state that our monitoring will provide. Additional monitoring based on mātauranga Māori will be co-developed with tangata whenua. We are also investigating ways for recreational divers to monitor and collect their own information to support the wider monitoring programme.
Some of the questions that we will be asking with our monitoring will include: changes in the various habitat types and extents represented in the protection areas (e.g. kelp forest, sponge gardens, kina barrens) and quantitative data on the biodiversity that the reefs and habitats support (e.g. fish species). Continued monitoring using the same methods over time will allow us to measure changes that may occur because of the protections. For example, the changes in fish numbers or the biodiversity associated with kelp forests. Ultimately, this will tell us if the Motiti Protection Areas are protecting and enhancing biodiversity.
Current monitoring programme
There are three main components to the monitoring programme, which include baited remote video surveys, diver habitat and species surveys, and deep reef surveys with remote operated vehicles (ROV). Additional research work in the Motiti Protection Areas is also being conducted by the University of Waikato.
Baited underwater video
Baited underwater video involves dropping a baited frame and video camera down onto the reef for a set period, to observe fish activity. Baited underwater video is a low impact sampling method which provides information on the number and size estimates of scavenger and carnivorous reef-fish species that often can be difficult to survey using divers. The videos are used to count the fish numbers and species and can also be used for size estimates. This is a standard method used for monitoring marine reserves around New Zealand, ensuring our results are comparable with Department of Conservation marine reserves.
A total of 82 sites are monitored across a number of the reef systems, including Okarapu, Otaiti, Motuhaku, Motunau and Motiti. The monitoring takes place between February – April each summer. This survey is designed to capture the range of habitats within 0 – 40m deep, including shallow mixed algae, kina barrens, kelp forests and sponge gardens.
You can read about the results from the first survey in our report. Future reporting will be conducted after we have gathered a number of years of information to build a picture about trends over time.
We are collaborating with Department of Conservation and Wildlife AI to utilise artificial intelligence and citizen science to help process the videos collected. This will allow members of the public and marine learning institutes to get involved in the monitoring of these special areas. For an example of this or to get involved visit Spyfish Aotearoa.
Scuba Diver Surveys
Scuba diver surveys are being used to monitor the abundance of reef fish, grazing invertebrates (such as sea urchins), and the coverage and health of kelp forests. Monitoring is occurring at Okarapu, Otaiti, Motuhaku and Motiti, with a total of 160 quadrats, 96 fish surveys and 32 video transects being collected each year. Sites were selected to align with historical monitoring locations, and some locations have continuous acoustic monitoring (using sound to monitor biodiversity) run by the University of Waikato. Each reef has two representative monitoring locations, with a shallow (5 -10m) and deep (15 – 20m) site within the location (8 locations, with 2 sites at each location).
Fish monitoring is being undertaken using underwater visual census and video. Random 50m long transect lines are laid out across the seafloor, and all fish observed within a set area of the transect are counted and size estimated and recorded underwater. A permanent record of the transect is also taken using video.
Habitat monitoring is being undertaken using 1m2 quadrats and video surveys. At each site, 10 quadrats are deployed and used to take a representative subsample of the wider monitoring site. In each quadrat the divers are recording: habitat type, urchin number and size (both kina and black long spined sea urchin), kelp number, kelp height and health, cover of other benthic habitat (e.g. sponges, other seaweeds), and number of other invertebrate species (e.g. cooks turban snail, crayfish). Additional surveys are planned to map the size and extent of kina barrens.
Future reporting will be conducted after we have gathered a number of years of information to build a picture about trends over time.
Deep Reef Biodiversity
Deep reefs (>30m depth) are generally outside of recreational scuba diving limits, and therefore to date we have little information about the types of species and habitats that are present on these reefs. A project is underway utilising drop cameras and remote operated vehicles (ROV) to take video footage of a number of deep reefs, ranging from 40 – 80m depth around the Motiti Protection Areas. ROV’s are small underwater robots with a video camera attached, allowing us to collect photos and videos from deep areas outside of the depths that we can safely scuba dive.
The research is a collaboration with DOC and University of Waikato, which aims to increase our understanding of what habitats we have in the area, what species they might support (e.g. special fish, sponges, or rare habitats).
Areas surveyed so far include Nukutai (northern Motiti), Brewis Shoal, and Motuhaku. Early results indicate a very diverse ecosystem including sponges, bryozoans, and soft corals (including black coral).
Completed Research Reports
