Most fishing methods catch target and non-target (unwanted) species, and unwanted catch may be returned to the sea in some cases.
Fishers and observers record catches of target and non-target species, and the amount of catch returned to the sea (discards).

Total non-target catch and discards for key species and species groups reported in the hoki, hake, ling, silver warehou, and white warehou (HHLSW) fishery from fishing years 2003 to 2022 were estimated with a statistical model.

Hoki and other target species make up most of the catch in this fishery, and key non-target species inluded javenlinfish, rattails, and sharks.
Gemfish showed a significant increasing trend in the amount of non-target catch reported, and sharks and slickheads showed significant decreasing trends.

The amount of catch that is discarded compared with the target catch is lower for this combined fishery than for other fisheries that are monitored.

Monitoring levels of catch and discards is important for understanding the impact of fishing on the environment.

The trawl footprint describes how much seabed area has been contacted by trawling gear in New Zealand’s territorial sea (TS) and exclusive economic zone (EEZ), but it does not provide a measure of the effect of fishing on seabed communities.

This project used the trawl footprint information, in addition to other sources of information on impacts of contact by trawl gear on seabed fauna, to quantify the potential impacts to seabed communities and habitats.

Fishing gear types were first described and categorised, and footprints for each category of gear were produced. Two published impact assessment methods were applied to the TS and EEZ. The methods had different strengths and weaknesses and the outputs of the two methods were found to be complementary to one another.

The first method applied, the MRSP approach, combines information on gear categories, expert opinion on the vulnerability of seabed fauna to trawl gear, and the bottom contact footprint of trawl fishing. This approach does not consider how the fauna recover over time.

The second method, the relative benthic status (RBS) approach, uses information on the proportion of the seabed area swept by trawls and published information for depletion and recovery rates for seabed fauna considered to be particularly vulnerable to trawling. This method predicts a future state for the seabed fauna assuming no change to fishing effort.

This project provides outputs for both methods that can be used in conjunction with distribution data for seabed fauna to assess impacts of trawling and inform spatial planning processes.

Recognising the shortcomings of the MRSP and RBS approaches, two further approaches were explored and developed using data from the Chatham Rise. One approach aimed to enhance the RBS method by making this more relevant to local seabed fauna by using bycatch data from the Chatham Rise instead of relying on information from international sources. The results were encouraging but indicated that further method development is required.

The second approach expanded a previously applied spatio-temporal modelling approach to assess impacts to fauna thought to be useful indicators of potential trawling effects. It was found that this approach, as with the others, was limited by the available data, and further development is required to improve the utility of this approach in the future.

Snapper are the most important recreational fish species in New Zealand and are often released back to the sea after capture.
Little is known about the survival of fish after they are released.
NIWA conducted a study using volunteer fishers to catch 960 snapper at different depths and with different hook placements.
The captured snapper were kept in holding nets and monitored by NIWA divers over several days.
Fish hooked in the lip had a low chance of dying if caught at shallow depths, but the chance of dying increased as depth increased.
Fish hooked elsewhere on the body had a higher chance of dying, with those hooked deep in the gut having the highest chance of dying.
This study suggests that fishing practices can impact fish survival, but there are ways to potentially reduce post-release mortality.
Understanding how fishing affects fish survival is therefore an important consideration for catch and release fisheries and when setting catch limit regulations.

Research report part of the 'Revitalising calf rearing' project funded under Sustainable Food and Fibre Futures.

With funding from Fisheries New Zealand and support from the Department of Conservation (DOC), we trialled attaching short-term (24 hours) suction-cup recording tags (DTAGs) to Hector’s dolphins in Te Koko-o-Kupe/Cloudy Bay.

We wanted to determine if DTAGs are a possible tool for monitoring this endangered species and could help answer research gaps identified by DOC’s Threat Management Plan and Research Strategy.

We found these suction-cup DTAGs had little to no impact on Hector’s dolphin behaviour.

We tagged 11 dolphins, and their tags stayed attached for 1.5 to 24 hours.

We gathered over 83 hours of data on this species, including the first ever three-dimensional recordings of Hector’s dolphin underwater, their night-time movements, and recordings of the different sounds they make and hear during a typical day.

Overall, such insights about these dolphins can influence how we manage them in relation to their various threats.

This policy statement signals high level policy expectations for the production, manufacture and sale of novel foods cultured from animal cells. It sits alongside the New Zealand Food Safety (NZFS) regulatory statement for any business proposing to import, manufacture or sell an animal cell-cultured food product for human consumption in the New Zealand market under New Zealand food legislation.