The main breeding population of New Zealand (NZ) sea lions (Otariidae: Phocarctos hookeri) at the Auckland Islands has declined by about 50% since the late-1990s. This population displays numerous indicators of nutritional stress, but the precise mechanisms of this stress (e.g., essential prey species and changes in their availability to NZ sea lions) remain poorly understood. This precludes a meaningful assessment of the effects of environmental change or indirect fishery effects on NZ sea lion populations.

The accuracy of at-sea identification of six species of deepsea sharks by MPI observers was determined by NIWA using photographs taken at the time of sampling. DNA barcoding analysis was also used to identify specimens that lacked photographs, using muscle tissues taken by the observers from each shark specimen. The six species sampled in the study were:
• Seal shark Dalatias licha, BSH
• Leafscale gulper shark Centrophorus squamosus, CSQ
• Owston’s dogfish Centroscymnus owstonii, CYO
• Longnose velvet dogfish Centroselachus crepidater, CYP
• Baxter’s lantern dogfish Etmopterus granulosus, ETB
• Plunket’s shark Proscymnodon plunketi, PLS

Data from two surveys to characterise biogenic habitats identified through Local Ecological Knowledge interviews are reported. The results demonstrate that New Zealand’s continental shelf supports a diverse range of habitats and species, many of which have not yet been formally described by science. At selected sites, the key habitat-forming species were identified, and the invertebrate species composition and associated fish communities described over localized spatial scales, and depth ranges.

CatchMapper provides heat maps and spatial estimates of catch and effort anywhere in the EEZ for all types of commercial fishing except eel fishing. This report describes the fishing represented in CatchMapper from October 2007 to September 2016 as well as the procedures for building polygons for fishing events, apportioning trip landings to each event polygon, and the range of ways the values of each polygon can be classified, pooled, and cut into spatial catch estimates and maps.

This report summarises bycatch and discards of fish and invertebrates in New Zealand arrow squid and scampi trawl fisheries for 2002–03 to 2015–16, based on analysis of fisheries observer and commercial catch effort data. Barracouta, silver warehou, and spiny dogfish were the main bycatch species in the arrow squid fishery, with total annual bycatch of 9000–40000 t and discards of 1000–16000 t. Javelinfish, other rattails, and sea perch were the main bycatch species in the scampi fishery, with total annual bycatch of 2400–5600 t and discards of 900–4100 t.

Research on black petrel at Little Barrier and Great Barrier Island in the 2016/17 breeding season followed 448 black petrel study burrows; of these 65% were occupied by breeding pairs and breeding success was 68%. Annually adult survival was 95%. Passive acoustic monitoring confirmed black petrels are concentrated within the summit ridges on Little Barrier Island and the Mt Hobson area on Great Barrier Island. Satellite GPS devices tracked 3 fledglings following an eastward migration route.

In New Zealand, captures of seabirds and other protected species are recorded by government observers when they are on-board commercial fishing vessels. This report addresses the question of how many seabirds would be reported caught if every commercial trawl and longline vessel fishing within New Zealand’s Exclusive Economic Zone carried an observer. Statistical models were used to scale up from observed captures, to estimate total captures across all commercial trawl and longline fisheries. Estimates were made for the 2002–03 to 2014–15 fishing years for trawl fisheries, and for the 1998–99 to 2014–15 fishing years for longline fisheries.

The Ministry for Primary Industries (MPI) is developing a risk assessment framework to identify the nature and extent of risks to chondrichthyan populations. This project aims to fill some of the knowledge gaps for some of the high-risk, non-Quota Management System species to reduce the level of uncertainty in the risk assessments of those species, and to provide information on their productivity that can then be used as inputs into future quantitative risk assessments. The species included in this study were seal shark (Dalatias licha), Owston’s dogfish (Centroscymnus owstonii), longnose velvet dogfish (Centroselachus crepidater), and Plunket’s shark (Scymnodon plunketi). Specimens and data were collected aboard commercial fishing vessels and research vessels, and integrated with existing data and specimens held by NIWA.

Age and growth were estimated for carpet shark, common electric ray and blind electric ray from growth increments on their vertebrae and eye lenses. All three species grow moderately fast, and longevity is low to moderate compared with other elasmobranchs. Length and age at maturity, length at birth/hatching, and litter size were estimated. The length of the gestation period, and whether females have a resting period between pregnancies, are poorly known.

Historical information indicates an increasing range of fish and invertebrates were exploited in these regions once commercial fisheries were established in the 1860s. Noticeable declines in abundance of easily exploited species occurred in the late 19th and early 20th centuries prior to the collection of fishery statistics. Until 1935, action to conserve fisheries was greatly impeded by a lack of consistently collected landings data. Similar studies of other regions would be beneficial.

Historical information indicates an increasing range of fish and invertebrates were exploited in these regions once commercial fisheries were established in the 1860s. Noticeable declines in abundance of easily exploited species occurred in the late 19th and early 20th centuries prior to the collection of fishery statistics. Until 1935, action to conserve fisheries was greatly impeded by a lack of consistently collected landings data. Similar studies of other regions would be beneficial.

The bottom-contacting deepwater Tier 1 and Tier 2 target fishstock footprint for 1990–2016 was estimated at 335 812 km2. This represents 8.2% of the Territorial Sea and EEZ seafloor area and 24% of the seafloor open to fishing, down to 1600 m. Tier 1 fisheries accounted for 93%, with hoki effort contributing 50%. The 2016 footprint covered 44 261 km2, 76 km2 of which was not contacted during 1990–2015. The aggregated swept area was 3.07 million km2 for 1990–2016 and 78 372 km2 for 2016.

This report documents the preparation of data on observed protected species captures in New Zealand fisheries during the period between 2002–03 and 2014–15. Recorded captures included captures of seabirds, marine mammals, and turtles. The observer records were linked to fishing effort data, and corrections to capture records and species identifications were made, prompted by expert reviews through necropsies and photograph examinations.

This supplementary information supports the risk assessment of the impact of fishing-related mortalities on seabirds breeding in the New Zealand region. It provides summaries of population and distributional data for the 71 seabird taxa included in the risk assessment. The distributional maps include breeding and non-breeding distributions and also present observer data of incidental captures in commercial fisheries.