This report describes relationships, patterns and contrasts in benthic species composition, assemblages and habitats, both within and between sites and initial sampling strata across the Challenger Plateau and Chatham Rise. Data used came from four different fauna collection methods: DTIS video; seamount sled; still images taken along the DTIS video; and beam trawls.
A 2013 workshop Future proofing New Zealand’s shellfish aquaculture: Monitoring and adaptation to ocean acidification, brought together experts from government, the aquaculture industry and science organizations from the US and NZ to raise awareness of ocean acidification within the NZ aquaculture community, identify ways to protect the aquaculture industry and develop US-NZ scientific cooperation to address OA. Papers presented at the workshop and points raised during discussion are summarised.
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 report provides results for the 20th summer trawl survey of hoki, hake, ling, and associated species in the Sub-Antarctic carried out from 23 November to 23 December 2022. Seventy-four of the 80 planned phase one stations were completed; there was no time to carry out phase two.
When compared with the previous survey in 2020, biomass estimates in core strata (200–800 m depths) were up by 31% for hoki, up by 10% for ling, and down by 25% for hake. The precision target (coefficient of variation) of 15% was met for hoki and ling but slightly exceeded for hake.
The hoki length and age distributions were mainly adult fish with few 1+ fish (2021 year class, fish less than 45 cm) and few 2+ fish (2020 year class, 45–55 cm). The hake and ling length and age distributions were broad, with few juvenile fish.
The acoustic estimate of midwater fish abundance was lower than that in 2020 but still above the average of the time series.
A total of 188 species or species groups were caught, of which 88 different species of fish and squid (29 560 fish) were measured, and 12 320 fish were individually weighed during the survey.
This report presents a description of the distribution of the ling (Genypterus blacodes) trawl and longline fisheries on the west coast of the South Island (LIN 7WC), from 1989–90 up to the 2018–19 fishing year. Catch-per-unit-effort analyses of standardised for commercial line fisheries targeting ling and as bycatch in observed trawl fisheries on the west coast of the South Island (LIN 7WC) are also presented
This report presents available New Zealand commercial fishery catch-at-age data for hake (Merluccius australis) caught by trawl, and ling (Genypterus blacodes) caught by trawl and longline, up to the 2018–19 fishing year, and bottom trawl survey catch-at-age data sets for both species up to the summer of 2020.
This report summarises the stock assessment of hake off the west coast South Island (WCSI) in HAK 7 for the 2021–22 fishing year. The index of abundance was the WCSI trawl survey. Initial spawning stock biomass was estimated as 78 870 t (95% CIs 74 140–84 810) with current status of 39% B0 (95% CIs 30–52% B0). Five-year projections showed that biomass would increase under average recruitment but would remain flat if future recruitments were low and catches were the same as the TACC.
The Marine Ecology Research Group used detailed field surveys to assess the recovery of the inshore coastal ecosystem affected by the cataclysmic 2016 Kaikōura earthquake.
The earthquake caused seismic uplift from 0.5 to 6.4 m along 130 km of coastline and resulted in widespread die-offs of important flora and fauna and permanent losses to critical habitats.
There was much concern for the fate of diverse intertidal and subtidal communities, which include culturally and commercially important fisheries, such as pāua, and other habitat-forming species like bull kelp.
Shore-based and dive surveys tracked the abundance of over 120 marine species at 16 sites for more than six years. Findings depict major physical and ecological changes over time across sites.
The complex dynamics of recovery are described in detail in this report and clearly show that the effects from this disturbance to the Kaikōura coastal ecosystem are both significant and ongoing.
This long-term study is the first of its kind and provides a detailed data set and quantitative baselines that will help inform future coastal management decisions.
This report describes catch-at-age distributions for hake (Merluccius australis) and ling (Genypterus blacodes) from commercial fisheries for the 2021–22 (2022) fishing year, to update an ongoing time series.
These distributions are based on length data and otoliths (ear bones for ageing fish) collected by observers from commercial fishing and research trawl data.
Catch-at-age data are important for the assessment of fish stocks because they provide information on the year class strength of age classes caught and are used in analyses of trawl surveys and commercial fisheries.
The precision target (coefficient of variation) was met for analyses of hake commercial trawl Sub-Antarctic and west coast South Island fisheries but not for the Sub-Antarctic trawl survey. The target precision was met for the Chatham Rise and Sub-Antarctic ling commercial trawl fisheries, and the Sub-Antarctic trawl survey, but not for the west coast South Island commercial trawl fishery. The target precision was met for the west coast South Island and Sub-Antarctic ling longline fisheries analysed.
Further observer data collection in certain areas and months are recommended to improve the precision of the hake and ling time series in future analyses.
This report summarises potential impacts of climate change on pests, weeds and
diseases of relevance to New Zealand’s biosecurity systems. It represents the best
current information from experts in the Crown Research Institutes and Lincoln University.
This report aims to develop a predictive lifetime feed intake model for sheep to enable sensitivity testing of different on-farm genetic and management technologies for methane mitigation.