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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.

This is the final report describing the results from the second and third years of a three-year programme to determine the costs and benefits of aerial 1080 possum control operations to North Island robins (Petroica australis longipes) and moreporks (Ninox novaeseelandiae) in Pureora Forest Park, North Island, New Zealand. During this study robins were individually colour-banded, and moreporks radio-tagged in both treatment and non-treatment study areas. A poison operation using carrot baits in August 1997 covered 8577 ha and incorporated the 300 ha Waimanoa study area. A poison operation using cereal baits in August 1998 covered just the 200 ha Long Ridge study area. After the 1997 operation, very few possums remained alive and rat foot-print tracking indices remained very low during the robin nesting season (September 1997 February 1998). Similarly, possum and rat population indices were much reduced after the 1998 operation, but rats and possums were found in a small portion of the study area, presumably because it did not receive baits. Following both the 1997 and 1998 poison operations, there was no significant difference in the proportion of banded robins that disappeared from the non-treatment and treatment study areas. During the 1997/98 nesting season, the nesting success of robins was significantly better in the treatment area than in the non-treatment area. One year after the poison operation (spring 1998), the robin population in the treatment area had increased by 37% on the number present just prior to the poison operation, compared with 16.3% in the non-treatment area. No radio-tagged moreporks were available in the treatment area during the 1997 poison operation, and all three radio-tagged in each of treatment and non-treatment areas were still alive two months after the poison operation in 1998.

In the report by Moore & Blezard· the object was to standardise mollymawk census methods by outlining reliable and repeatable count methods. This was intended to make it easier for future workers to repeat and/or interpret the counts of 1995-1997, and thus allow the monitoring of future population trends. The tabulated data from the counting were not essential to the method, and so were not included in Moore & Blezard (1999). The Data Supplements are presented here for the record, and for those who may wish to consult the tables for the counts conducted by Peter Moore (in 1990), Alastair Mclean (in 1993), and Reg Blezard (in 1997-1998).

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