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The report comprises four Parts. Part 1 presents an overview of risk analysis and its general application to the management of New Zealand's indigenous fauna and sets out a framework for risk analysis for indigenous fauna with reference to the example analysis for indigenous parrots in Part 3 of the report. Part 2 lists the indigenous vertebrate fauna populations of interest and considers, in general terms, the range of disease agents that need to be covered. A semi-quantitative method for prioritising each population of interest so as to allow an orderly progression of successive risk analyses based on each population's priority ranking is presented. Part 3 is an example evaluation of risk analysis for managing the threat of exotic disease to indigenous parrots (psittacines). Part 4 recommends the use of risk analysis as a standard and appropriate tool for the management of risk of exotic disease to indigenous fauna in New Zealand. The report recommends a number of actions that the Department of Conservation could make to reduce risk of exotic disease to indigenous psittacines in particular and indigenous fauna in general.

The Tahiti flycatcher (Pomarea nigra) is one of several monarch flycatcher species in the Polynesian genus Pomarea, all of which are threatened. The Tahiti flycatcher is currently known from only the western side of Tahiti where, during the 1998-99 season, at least 24 individuals, including 10 pairs, were located in four valleys (Blanvillain 1999). Although ten nests were protected from rats in 1998-99, only three were successful in fledging young. Two of these young apparently disappeared one week after fledging and the third, two months after fledging (Blanvillain 1999). Concern was raised about the possible predation by common myna (Acridotheres tristis), and/or red-vented bulbul (Pycnonotus cafer) on juveniles. In 1999-2000 the Societe d'Ornithologie de Polynesie (MANU) was granted funding for Tahiti flycatcher conservation by the South Pacific Regional Environment Programme (SPREP). During 13-26 September 1999, RP visited Tahiti to advise and help CB with aspects of the programme. This advisory work was funded by the N.Z. Ornithological Congress Trust Board (ICBP). It builds on work by Gaze & Blanvillain (1998) funded by the Pacific Development and Conservation Trust.

The Department of Conservation has assisted the Cook Islands Conservation/Environment Service, and more recently the Takitumu Conservation Area Project, to plan and implement a recovery programme for the endangered endemic forest bird, the kakerori.

Northern royal albatross (Diomedea sanfordi) eggs and chicks were collected at Taiaroa Head from 1995 to 1998 by Department of Conservation staff. Frozen whole eggs and chicks were submitted to ESR for chemical analysis. The analysis quantified the levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and a range of persistent organochlorine pesticides, including dichlorodiphenyltrichloroethane (DDT) group compounds. The total international dioxin equivalents (I-TEQ) ranged from 3.2 to 15.4 pg/g wet weight, while PCB concentrations (sum of 32 congeners) ranged from 15.7 to 89.2 ng/g wet weight. These values are very similar to the levels reported in northern royal albatross eggs collected from the Chatham Islands over the 1995 - 1996 period. Certain organochlorine pesticide residues were detected in all samples. The most prevalent were tachlor epoxide, which had mean concentrations in eggs of 58 ng/g, 6.2 ng/g, 5.0 ng/g and 1.2 ng/g wet weight, respectively. The profile of PCDD/F and PCB congeners was consistent with previous analysis conducted on northern royal albatross eggs from the Chatham Island. The profiles were also similar to those reported in albatross species from the North Pacific ocean. There was no apparent effect on the measured levels of sampling season (95/ 96 versus 97/98) or whether analysis was on eggs or chicks. The mean (range) I-TEQ values for eggs 1995/96, eggs 1997/98 and chicks 1997/98 were 8.14 (4.79 - 12.88), 9.91 (6.57-13.79) and 9.91 (3.20-15.37) pg/g wet weight, respectively. As all egg samples were from females of known age, the relationship between the age of females and the concentration of organochlorine residues in eggs was examined. No significant relationships were established. As an example, the regression between female age and egg concentration p,p'-DDE (y= -1.98x + 112.57) had a very weak r2 value of 0.155. The mean value and range for egg shell thickness was 0.57 min (0.53 - 0.63) indicating no egg shell thinning in the samples collected. The lack of egg shell effects and the similarity between residues in this study and samples previously collected from the Chatham Islands, suggests apparent reproductive impairment in Chatham Island albatross is not caused by the analysed organochlorine contaminants. The similarity of the organochlorine levels between Taiaroa Head and Chatham Island albatross suggests that previous conclusions regarding risk still apply: namely, that while the greatest risk of adverse effects to albatross are attributable to the I-TEQ, the residues are below the exposure levels where adverse effects would be expected to occur.

This is my report from the Scientific Committee meeting of the International Whaling Commission (IWC) held in Grenada from 3 May to 15 May 1999. An earlier draft was prepared for Jim McClay, NZ Commissioner to the IWC, for briefing on the issues discussed in the Scientific Committee. In this report I outline the important discussions that occurred in the Scientific Committee, particularly those issues that directly affect New Zealand. I attended three of the seven sessions, while Scott Baker, Steve Dawson and Mike Donoghue attended various parts of these three plus the other four sessions that I was unable to cover. New Zealand was very well represented at the meeting, which allowed coverage of all sessions even when three or four were running concurrently.

There are five toxicants (brodifacoum, bromadialone, coumatetralyl, diphacinone, and flocoumafen) registered for rodent control in New Zealand. They are all anticoagulants and are available in water-resistant bait formulations (i.e. wax coating, wax block, or egg). Several new rodenticide products, which are currently in the process of being developed or registered, including a new anticoagulant difethialone, have also been identified. There are no published data on the relative effectiveness, palatability, or durability of the existing rodenticides for field use under New Zealand conditions. However, relevant published information on laboratory and wild rodents is reviewed. It is concluded that the highest priority should be to assess the four weather resistant, second-generation anticoagulant products (Pestoff® Rodent block, Talon® 50WB, Contrac®, and Baraki®) for palatability, durability, and effectiveness for an island protection situation. Improvements could then be made to the existing products if required with additives to improve palatability or durability, lures to attract rodents, and repellents for non-target insect, lizard and bird species. Trials of an alternative (e.g. cholecalciferol) to the persistent anticoagulants should also be considered for island protection. The most rodent-attractive bait station which also eliminates bird access needs to be determined for the complete island protection system.

The number of humpback sightings and the number of whales recorded in this study suggest a slow increase over the last 10 years, particularly in the last 4 years. The results of this study may have been influenced by a variety of factors, the most important of which may be inconsistent effort. The results presented in this report are broadly consistent with that described by Dawbin (1956). As reported by Dawbin (1956), and found in this study, the northern migration occurs between May and August while the southern occurs from September to December. There is little evidence of a change in migration patterns past the New Zealand coast. The inability to quantify effort is a major limitation with the data and does not make it possible to draw clear conclusions on population size or trends in migration. However, the results are useful in determining the locality and seasonality of humpback whales as they migrate along New Zealand coasts.