
Scientific name: |
Odax pullus |
Other names: |
marari, matohe, tarao, kooaea, (Maori), greenbone, Bera-rui (Japan) |
Butterfish is an ok fish to eat but there are some concerns. Where possible we recommend trying to eat only butterfish caught in areas with minimal risk to Hector’s dolphins (east and north coast of the North Island). An alternative is trevally.
Butterfish is an endemic species of kelpfish found in shallow waters around the New Zealand’s coast. They are more abundant south of East Cape, especially around Cook Strait, where they are caught year round in set nets. Butterfish start life as female and about 50% later develop into males.
Butterfish are mainly caught by set nets. Concerns include the unknown status of stocks and population size, unknown sustainability of catch levels, absence of research, the lack of a management plan and the bycatch of non-target fish species. Restrictions on set netting have reduced the risk of catching endangered Hector’s dolphins in some areas. The bycatch of marine mammals and seabirds in set nets is still of concern.
Not certified under any scheme.
Butterfish is sold in New Zealand.
Asssessment output
No regional or fishing method difference.
Score: | D |
Population size: | Unknown. There are no estimates of current and reference biomass available. |
Annual catch limit: | Limit set at 162 tonnes since 2002. |
Recorded catch: | Reported landings of 97.1 tonnes in 2014-15, mainly in the Cook Strait and around Stewart Island. Recreational catch is estimated to be of a similar size. |
Stock trends: | Unknown |
MSY Status: | Unknown. |
The Ministry of Primary Industries assessment plenary report includes: | “No estimates of current and reference biomass are available. It is not known whether recent catch levels will allow the stock to move towards BMSY.” “Butterfish populations are susceptible to localised depletion.” (MPI 2011, p 221). |
Score: | B |
Distribution: | Found in shallow waters in rocky coastal areas of New Zealand and the Chatham Islands. It is most common in areas around Cook Strait. |
Maximum age (years): | 19 |
Age at sexual maturity: | 2-4. Larger fish are males that started life as females. |
Growth rate: | Moderate |
Reproductive output: | Medium to high |
Age exploited: | 2-3 |
Ability to recover: | Moderate |
Score: | C |
Fishing method(s): | Targeted set nets |
Habitat damage: | Low for set netting |
Habitat of particular significance: | hasn’t been defined in New Zealand. |
Bycatch: | Range of non-target fish caught in set nets. |
Ecological effects: | Butterfish are important kelp eating fish, so their depletion could have wider impacts on kelp forest ecosystems. |
Score: | B |
Bycatch: | Set nets pose a significant risk to threatened Hector’s dolphins. Changes made in the upper South Island have added risk to Hector’s dolphin. Commercial set net fishing is the top threat to Maui’s dolphin from the risk assessment, with trawl net fishing ranked second and half the rate of estimated mortalities. Captures of dolphins by both trawlers and in set nets has been documented. Set net targeting a range of non-shark and non-flatfish species are estimated to catch 75 seabirds annually. |
Score: | D |
Management component: | Single species. There is uncertainty over the nature of butterfish stocks: their larval development is short, creating the possibility of many stocks around New Zealand and multi-stock in quota areas. |
Score: | D |
Quota Management Species: | Yes, since 2002. |
Catch limits: | Yes |
Management plan: | There is no approved inshore plan. |
Stock assessment: | No quantitative estimates. |
Research: | There is no current directed research into butterfish. |
Observer coverage: | Unobserved to a maximum of 1.52% over last 5 years but it is not spatially or temporally representative of the fishing effort. |
Fisheries map
Taken from the Ministry for Primary Industries’ Plenary report for fisheries management.

References
Report from the Fishery Assessment Plenary, May 2016: stock assessments and yield estimates. Part 1: Introductory Section to Hoki, Science Group, Ministry for Primary Industries; Ministry for Primary Industries (2016) Aquatic Environment and Biodiversity Annual Review 2015. Compiled by the Fisheries Management Science Team, Ministry for Primary Industries. 682p. The Guidebook to New Zealand Commercial Fish Species, 2007 Revised Edition, The New Zealand Seafood Industry Council Ltd. Seafood New Zealand, 2016. New Zealand Seafood Exports to December 2015. 133p.