Technical Papers

Below you'll find a listing of MAF Biosecurity New Zealand's technical papers.


Mapping the Values of New Zealand's Coastal Waters. 2. Economic Values

Introduced species are recognised as one of the greatest threats to natural environments worldwide. New Zealand’s ability to assess and manage these risks is significantly hampered by a lack of detailed information on the resources that should be protected: Which species are of greatest concern? What values are at risk? Where should surveillance monies be concentrated? Which incursion can or should be responded to?

To help address these questions and thereby improve risk management in the marine environment, MAF Biosecurity New Zealand (MAFBNZ) commissioned research to map the economic, environmental, social and cultural values associated with New Zealand’s coastal and marine environments.


Reproductive behaviour of the Clubbed Tunicate, Styela clava, in northern New Zealand waters

December 2008

The reproductive behaviour of the invasive ascidian, Styela clava, was investigated in Auckland from May 2006 until April 2007. Results indicate that fertilised ova were present from late September 2006 through to April 2007. A spawning event appeared to occur in early spring, but indications for spawning were also found in mid-February and mid-March. Overall, the fluctuations observed in the spawning periods are indicative of a species that is able to reproduce at different times throughout the year. There does, however, appear to be a "lull" in reproductive potential over winter and in mid spring, with peaks in early spring and late summer.


Trial of a Control Programme for Non-Indigenous Crustaceans using Charybdis japonica as a case study

October 2008

The development of methods by which to control and, ultimately, eradicate marine pest species is necessary to safeguard the biodiversity within New Zealand's marine environment. This requires the development of control measures that are suitable for use in a range of different aquatic environments, which do not adversely affect the surrounding natural environment and native species nor disrupt human use of marine resources.

The non-indigenous Japanese swimming crab, Charybdis japonica was first detected in New Zealand waters in 2000 and has since become widespread throughout the Waitemata Harbour, Auckland. The presence of species provided an opportunity to develop and test an integrated pest management (IPM) strategy aimed at managing marine crustaceans.


Change in the benthic assemblages of the Waitemata Harbour

The Waitemata Harbour is a large tidal estuary adjacent to New Zealand’s largest and fastest growing city. The harbour is highly valued and is used for numerous recreational and commercial purposes. A potentially important stressor in the Waitemata Harbour has been the establishment and spread of non-indigenous species (NIS); with more than 66 marine NIS having been recorded. However, the ecological consequences of NIS invasions in the Waitemata Harbour have not been fully explored. It is important to investigate the role of native biodiversity in promoting invasion resistance, and the likelihood of “invasional meltdown” in the Waitemata Harbour.

The purpose of this investigation was to determine whether invasions in soft-sediment habitats of the Waitemata Harbour have affected key ecosystem functions to the extent that (1) resistance to new invasions has been compromised, and (2) ecosystem services have been affected.


Assessment of population management options for Styela clava

This report describes population management options for the non-indigenous clubbed tunicate Styela clava (Styela). The broad aim of this report is to evaluate options for the management of established Styela populations in Tutukaka Marina, Lyttelton Port and Magazine Bay Marina. The report aims to identify ways of reducing the chances of Styela spreading from these three vessel movement hubs to nominated high value coastal environments around New Zealand, and to provide information on control methods and the feasibility of implementing them at various scales.


Mapping the Values of New Zealand’s Coastal Waters. 1. Environmental Values

This project is the first systematic attempt to quantify measures of perceived environmental value of New Zealand’s coastal marine ecosystem through the creation of a series of spatially explicit data layers derived from existing data sources (including museum and scientific cruise records). It is anticipated that this unique project will have additional conservation and management benefits outside the biosecurity perspective.


Milford Sound: First baseline survey for non-indigenous marine species

May 2008

This report describes the results of the first port baseline survey of Milford Sound, undertaken in June 2006. The survey provides an inventory of native, non indigenous and cryptogenic marine species within the fiord and surrounding coastal area and compares the biota with existing marine species records from the area.


Second baseline Surveys for Non-indigenous marine species

May 2008

  • Port of Lyttleton Link to PDF document (1969 KB) - This report describes the results of a repeat port baseline survey of the Port of Lyttelton undertaken in November 2004.
  • Port of Nelson Link to PDF document (1416 KB) - This report describes the results of a repeat port baseline survey of the Port of Nelson undertaken in December 2004.
  • Port of Picton Link to PDF document (1268 KB) - This report describes the results of a repeat port baseline survey of the Port of Picton undertaken in January 2005.
  • Port of Taranaki Link to PDF document (1444 KB) - This report describes the results of a repeat port baseline survey of the Port of Taranaki undertaken in March 2005.
  • Port of Tauranga Link to PDF document (1322 KB) - This report describes the results of a repeat port baseline survey of the Port of Tauranga undertaken in April 2005.
  • Port of Timaru Link to PDF document (1648 KB) - This report describes the results of a repeat port baseline survey of the Port of Timaru undertaken in November 2004.
  • Port of Wellington Link to PDF document (1476 KB) - This report describes the results of a repeat port baseline survey of the Port of Wellington undertaken in February 2005.

No Frontiers in the Sea for Marine Invaders and their Parasites?

May 2008

This report describes the results of a study investigating the geographic distribution of two non-indigenous crabs, Romaleon gibbosulum and Glebocarcinus amphioetus (Decapoda: Cancridae), in the North and South Island of New Zealand. In addition, we investigated their size distribution, habitats and parasite fauna in their Japanese native range. The parasite fauna of the New Zealand native crab Metacarcinus novaezelandiae (Decapoda: Cancridae) was also investigated to assess whether they have parasites that might potentially infect the two non-indigenous cancrid crabs and therefore could be used for controlling invader populations. Finally, we reviewed the diversity and occurrence of non-indigenous crabs (Brachyura) worldwide to identify patterns in their invasion biology.


Surveillance for early detection of unwanted exotic marine organisms in New Zealand

December 2007

This report describes the results of the continuation of a targeted surveillance programme for marine pests that are currently listed on the New Zealand register of Unwanted Organisms under the Biosecurity Act 1993. Surveillance began in summer 2002/2003 and continued at six-monthly intervals until winter 2004. The results of these first four surveys were reported previously (Inglis et al. 2005a). This report presents the results of the fifth survey conducted in summer 2005-2006.


Development of standards for hull cleaning facilities

Hull fouling is an important pathway or vector for the introduction and spread of marine non-indigenous species (NIS) in New Zealand. This project (ZBS2005-22, summer) sought to determine the seasonal risk to marine biosecurity of vessel hull cleaning (defouling) and assess the efficacy of hull cleaning methods and effluent treatments in reducing this risk, by comparison with an initial examination of the efficacy of various hull cleaning techniques and facilities carried out in the winter of 2003 (ZBS2002-04) (Floerl et al. 2003). The five facilities assessed in ZBS2002-04 were revisited during the 2005/06 summer season. These facilities were: Lyttelton Port, Orams Marine Maintenance, Westpark Marina, Tauranga Marina and Gulf Harbour Marina.


Genetic diversity and possible origins of New Zealand populations of Ulva

May 2007

The genetic diversity of the green algal genus Ulva sensu lato in New Zealand was surveyed to identify the species present, and to assess their status as native or potentially introduced entities. Data were obtained for 581 samples collected from within the New Zealand EEZ, ranging from the Kermadec Islands to the Auckland and Antipodes Islands. Both pristine and human-modified environments were represented in the sampling sites visited.

This document is available in two versions. The high resolution copy has better quality images. Please be aware that both have a large file size.


Surveillance design for early detection of unwanted exotic marine organisms in New Zealand

April 2006

This report describes the design and trial of a targeted surveillance programme for seven marine pests that are currently listed on the New Zealand register of Unwanted Organisms under the Biosecurity Act 1993. These are the Asian kelp Undaria pinnatifida, the Mediterranean aquarium weed Caulerpa taxifolia, the Northern Pacific seastar Asterias amurensis, the Mediterranean fanworm Sabells spallanzanii, the European green crab Carcinus maenas, the Chinese mitten crab Eriocheir sinensis, and the Asian clam Potamocorbula amurensis. The Asian kelp U. pinnatifida is already present in New Zealand.


Baseline Surveys for Non-indigenous marine species

March 2006

  • Port of Lyttleton Link to PDF document (2834 KB) - This report describes the results of a March 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Lyttleton.
  • Port of Nelson Link to PDF document (1634 KB) - This report describes the results of a January 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Nelson.
  • Port of Picton Link to PDF document (894 KB) - This report describes the results of a December 2001 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Picton
  • Port of Taranaki Link to PDF document (1992 KB) - This report describes the results of a April 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Taranaki.
  • Port of Tauranga Link to PDF document (2421 KB) - This report describes the results of a March 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Tauranga.
  • Port of Timaru Link to PDF document (2138 KB) - This report describes the results of a February 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Timaru.
  • Port of Bluff Link to PDF document (2522 KB) - This report describes the results of a March 2003 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Bluff.
  • Port of Auckland Link to PDF document (2857 KB) - This report describes the results of a April 2003 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Auckland.
  • Port of Wellington Link to PDF document (3250 KB) - This report describes the results of a December 2001 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Wellington.
  • Port of Dunedin Harbour (Port of Otago and Port Chalmers) Link to PDF document (3657 KB) - This report describes the results of a February 2003 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Dunedin (this includes Port Otage, located near the city of Dunedin, and Port Chalmers facility).
  • Port of Gisborne Link to PDF document (2453 KB) - This report describes the results of a January 2003 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Gisborne.
  • Gulf Harbour Marina Link to PDF document (2649 KB) - This report describes the results of a April 2003 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Gulf Harbour Marina.
  • Port of Napier Link to PDF document (2324 KB) - This report describes the results of a January 2003 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Napier.
  • Opua Marina Link to PDF document (2442 KB) - This report describes the results of a November 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Opua Marina.
  • Whangarei Marina Link to PDF document (2154 KB) - This report describes the results of a November 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Whangarei Town Basin Marina.
  • Whangarei Harbour (Whangarei Port and Marsden Point) Link to PDF document (3391 KB) -This report describes the results of a November 2002 survey to provide a baseline inventory of native, non-indigenous and cryptogenic marines species within the Port of Whangarei, located near the city of Whangarei, and shipping terminals at Marsden Point operated by Northport and the New Zealand Refining Company.

Didymo research reports

The overall objective of the science and technical programme is to determine validated information regarding identification, detection, distribution, containment, impact and control/eradication of Didymosphenia geminata (didymo). All reports can be found at the link below:


A Diagnostic Guide to Tortricidae

The purpose of this guide is to facilitate reliable and practical determinations of tortricid specimens collected in the execution of biosecurity functions in New Zealand. The guide is also useful to agencies and individuals outside of New Zealand who seek the identification of New Zealand leaf-rollers.

The guide consists of a series of integrated morphological and molecular diagnostic keys, including keys to later instar larvae, male and female adults; a table of diagnostic characters for early instar larvae; and notes for all the species. There are 374 images, most of them in colour. The images are reproduced on a CD to allow closer examination, especially of the genitalia and improved search capacity.

The list of species covered in this guide is restricted to 50 or so economically important Tortricidae species. These include taxa from New Zealand, as well as exotic Tortricidae species most likely to be introduced here.

Page last updated: 30 June 2009