New Zealand Aquatic Environment and Biodiversity Report No. 217. 62 p.

This study provides an indicative assessment of vessel traffic and seismic survey related noise. Vessel AIS data for the year of July 2014 to June 2015 was used to determine density and speed grids by vessel category. JASCO’s cumulative vessel noise model was used to model the sound from 15 vessel categories and two marine seismic surveys during representative summer and winter months in 1-minute time steps. Results are presented as maps, animations and plots of sound levels at static locations.

New Zealand Aquatic Environment and Biodiversity Report No. 215. 18 p.

A Bayesian Māui dolphin population model was developed integrating information from genetic “mark-recapture” and population size estimates. Model runs incorporated estimates of historical annual deaths from commercial fisheries and toxoplasmosis obtained from a separate spatial risk assessment. These models were then used to simulate the effects of estimated threat-specific mortality rates on future population growth.

New Zealand Aquatic Environment and Biodiversity Report No. 214. 168 p.
(Manuscript 3334)

A spatial risk assessment of threats was undertaken for Hector’s and Māui dolphins, to inform a revised Threat Management Plan (TMP) for the species. A Bayesian risk model was developed using the spatially-explicit fisheries risk assessment (SEFRA) approach, incorporating revised estimates of Hector’s and Māui dolphin spatial density and intrinsic population growth rate. The risk model was used to estimate spatial overlap, annual deaths and risk for commercial fisheries and lethal non-fishery threats, including toxoplasmosis. Spatial overlap was estimated for other threats.

Francis, M.P.; Hoyle, S.D. (2019). Estimation of fishing effort in the Southern Hemisphere.

New Zealand Aquatic Environment and Biodiversity Report No. 213. 24 p.

This report estimates the high seas fishing effort expended in the Southern Hemisphere by the main methods likely to impact seabirds (surface and bottom longline, and trawl). Data were sourced from 10 Regional Fisheries Management Organisations. Effort totals are biased low (sometimes substantially) in some regions and times, although the degree of under-estimation has probably declined through time. These estimates will be used in a subsequent quantitative risk assessment of seabirds.

978-1-98-859461-3

(Manuscript 3308)

Alestra, T.; Gerrity, S.; Dunmore, R.A.; Marsden, I.; Pirker, J.; Schiel, D.R. (2019). Rocky reef impacts of the Kaikōura earthquake: quantification and monitoring of nearshore habitats and communities.
New Zealand Aquatic Environment and Biodiversity Report No. 212. 120 p.


Surveys along 130 km of coastline in the first sixteen months following the Kaikōura earthquake showed significant damage to intertidal benthic communities at all sites. Subtidal communities were impacted only at sites with uplift greater than 2 m. Taonga species such as paua and bull kelp were still present at most sites and showing signs of post-earthquake recruitment. This information provides a key baseline for management decisions and new research into long-term trajectories of recovery.

Manuscript 3269

This assessment presents bycatch estimates of seabirds in commercial trawl and longline fisheries in New Zealand’s Exclusive Economic Zone. The estimation relied on statistical models that used fishing effort and observer data up to the 2015–16 fishing year. Estimates for the latter fishing year included a total of 4517 (95% credible interval: 3760–5825) seabird captures in trawl and longline fisheries in New Zealand waters.

A reassessment of population size and trends of Hutton’s shearwater following the 2016 Kaikōura earthquake and outlook for the species’ management.

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 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.

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 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.

This study provides an assessment of the impact of fishing-related fatalities on the populations of 35
marine mammal (sub)species that inhabit New Zealand waters. The assessment included mortalities
caused by trawl, longline, set-net and purse-seine fisheries within New Zealand’s Exclusive Economic
Zone (EEZ). The risk assessment was an implementation of the Spatially Explicit Fisheries Risk Assessment
(SEFRA) method. Risk was defined as the ratio of Annual Potential Fatalities (APF; an estimate of
the number of marine mammals killed in fisheries each year) to the Population Sustainability Threshold
(PST; a measure of the population productivity). A risk index higher than one indicates that fisheries
mortalities are at a level that may prevent the population increasing to, or remaining above, half the
carrying capacity in the long term.

The seabird risk assessment provides risk rankings for seabirds in commercial fisheries in New Zealand waters. This study used simulated fishing effort and observer data to test the sensitivity of the seabird risk assessment to a reduction in observed captures. The results indicate that, because of low observer coverage, the government will be unable to demonstrate that seabird risk reduction goals have been met, even if no seabird captures are reported by observers for three years.

Oral histories of 58 Māori and non-Māori individuals indicate the historical importance of daily fishing and gathering to some household economies in the Hauraki Gulf and along the Otago-Catlin coast, especially in the years before widespread refrigeration. Fish and shellfish were formerly very abundant and could be reliably caught with little effort, often from the shore with simple equipment. They tell a story of decreasing availability and size of key kai moana species.

A large multi-disciplinary project was conducted to determine the effects of climate variation and human impact on the structure and functioning of New Zealand marine shelf ecosystems over the timescale of human occupation in New Zealand from about AD 1250 to the present day. This report summarises and synthesises the 18 contributing reports to describe the major changes to New Zealand marine ecosystems over the time period and discuss the overall implications of the results for marine conservation and management.