The Chatham Rise is a special fishery because its topography and associated currents make it very productive. As such, it has been the subject of detailed study and provides an exemplar of how data can enrich models and enable long-term ecological monitoring – and how resource intensive this data gathering can be.
Fisheries New Zealand contract a survey by NIWA, which has been done annually since January 1992 with RV Tangaroa, and biennially since 2014. The total of 26 surveys have collected data on over 300 species per survey; biomass is well monitored for about 50 species and size frequency data are collected on about 45 species each survey. Consequently, we have more fisheries data available for the Chatham Rise than almost anywhere else in Aotearoa New Zealand. The Fishecoviz portal summarises (30+) key species’ biomass and will summarise size frequency data as well to generate ecological indicators for monitoring (see section ‘An improved data system can help us move from data to information’).
Phytoplankton bloom on the Chatham Rise. Image credit: Norman Kuring, Ocean Color Team/NASA Goddard Space Flight Center.
The rich dataset is used to develop the Atlantis model with a growing number of parameters, in addition to trawl surveys (acoustic surveys, diet studies, benthic and habitat studies, growth and age studies, oceanographic models, nutrient climatological data, commercial fishery catch and effort, and stock assessment models). The Atlantis model is further discussed in ‘Models can support ecosystem approaches to fisheries management’.
The model has been well described in the literature.[1–4]
Chatham Rise survey area showing strata used for trawl surveys.
References and footnotes
[1] McGregor, V. L. et al. (2019a) From data compilation to model validation: A comprehensive analysis of a full deep-sea ecosystem model of the Chatham Rise, PeerJ, 2019(2), pp. 1–42.
[2] McGregor, V. L. et al. (2019b) Spawning stock recruitment creates misleading dynamics under predation release in ecosystem and multi-species models, PeerJ, 2019(7).
[3] McGregor, V. L. (2020) Extending process and understanding for the development of complex ecosystem models, with application to the Chatham Rise Atlantis model. A thesis submitted for the degree of Doctor of Philosophy at Victoria University, Wellington, New Zealand.
[4] McGregor, V. L. et al. (2020) Addressing initialisation uncertainty for end-to-end ecosystem models: Application to the Chatham Rise Atlantis model, PeerJ, 2020(6).