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The blue penguins (genus Eudyptula) have been subjected to extensive taxonomic revision. In 1976, the genus was reduced from 2 species to a single species (Eudyptula minor) with 6 subspecies, based on a morphometric analysis. Despite the later proposed rejection of the differentiation of subspecies in Eudyptula minor, following analysis of allozymes in some populations, the 6 subspecies have continued to be recognised in some popular and scientific literature. We compared the sequences of 3 mitochondrial gene regions (small ribosomal subunit, cytochrome oxidase b and the control region) from the 6 hypothesised subspecies to examine relationships within Eudyptula. We found evidence for 2 unexpected clades: the 1st consisting of Otago and Australian populations, the 2nd consisting of north- ern, Cook Strait, Chatham Island, and Banks Peninsula populations. Some support for these 2 clades was also found from a re-analysis of morphometric data and from a preliminary examination of vocalisations.

The population of Providence petrels (Pterodroma solandri) that nested on Norfolk Island at the time of 1st European settlement of that island in 1788 was probably >1 million pairs. Available evidence indicates that Europeans harvested many more Providence petrels in the years immediately after settlement than previously believed. About 1,000,000 Providence petrels, adults and young, were harvested in the 4 breeding seasons from 1790 to 1793 alone. Despite these enormous losses, many Providence petrels were apparently still nesting on Norfolk Island in 1795 when they are last mentioned in documents from the island. However, any breeding population that may have survived there until 1814 when Norfolk Island was abandoned temporarily was probably exterminated by the combined activities of introduced cats and pigs which had become very numerous by the time the island was re-occupied in 1825.

We investigated whether breeding frequency and breeding success of southern Buller’s mollymawks (Thalassarche bulleri bulleri) were influenced by breeding experience and pair bond duration, using data from annual checks at 3 study colonies at The Snares from 1992 to 2001. Most pairs bred annually irrespective of the experience and length of the pair bond, although the proportions that did so varied with pair type. Thus, breeding frequency (% breeding in consecutive years) was lowest among pairs of 1st-time breeders (77%). Breeding frequency of those pairs after their 2nd attempt (89%) became similar to that of established pairs together for at least 1 previous breeding attempt (88%), or newly formed pairs in which one or both birds had previous breeding experience (91%). Overall breeding success was 71% and, in established pairs, breeding failure (loss of egg or chick) was associated with reduced breeding frequency (83% compared to 91% when successful). Lowest breeding success (58%) was associated with the attempts of 1st-time breeders. Performance of these pairs improved until the 3rd attempt (81%), when it became similar to that of established pairs (73%) and newly formed pairs in which one or both birds had previous breeding experience (77%). Divorce was rare (1.1-3.5% annually). First-time and former breeders mated more frequently with birds of similar status (85% and 58% respectively) than expected assuming random pairings. When changing partner, as a result of divorce or death, the average interval before breeding again was 2.1 years for males and 2.6 years for females, and so, on average, each change of partner resulted in the loss of 1 breeding attempt. Thus, the time taken to obtain a new partner has a lifetime reproductive cost.

We studied the breeding biology of a colony of Caspian terns (Sterna caspia) near Invercargill, New Zealand, during 1992 and 1993. The mean clutch size did not differ between years and averaged 2.04. Measurements of 147 eggs averaged 64.5 x 44.6 mm; there was no difference in size of A-eggs (1st-laid in a clutch) and B-eggs (2nd-laid) in either year, but the few C-eggs laid were significantly smaller. The incubation period averaged 27.2 days (range 26-29 days); some earlier published values of 20-22 days appear to be in error. In 1992, growth rates of A-chicks were significantly higher than those of B-chicks. Growth rates of A-chicks were significantly higher in 1992 than in 1993. Fledging occurred at 33-39 days at an estimated average mass of 527 g in 1992 and 501 g in 1993. Minimum productivity was 1.04 and 0.62 chicks fledged per pair in 1992 and 1993, respectively. Weather during the period of chick growth was much wetter and windier in 1993 and we suggest that this reduced the ability of parents to feed chicks. Investigator disturbance, which has been implicated in lower reproductive success in some studies of Caspian terns, did not appear to have a major impact in our study. We believe this was partly because the birds were habituated to our activities and partly because of our methodology.

We investigated the annual survival of Finsch’s oystercatchers (Haematopus finschi) breeding on farmland in mid-Canterbury, New Zealand. Annual survival from 1987 to 2000 averaged 0.892, with evidence of a small amount of variation in survival rates through time (estimated SD = 0.034). We found no indication that survival rates differed between males and females. However, recapture probabilities showed that males had stronger fidelity to breeding territories than did females. These results are similar to those reported from populations of H. ostralegus in Europe. Because oystercatchers are long-lived, the survival rate of adults is the key component in determining population size. Intensification of agriculture on the breeding grounds and disruption to coastal feeding grounds may reverse the trend for population increase in this species. Consequently, the survival rate presented here provides a basis for predicting future population trends.

The night-time activity of grey-faced petrels (Pterodroma macroptera gouldi) was measured at a colony on Tiritiri Matangi Island between 27 April and 10 December 1998. Considerable seasonal variation was observed (0 to >120 birds/night). A decline in numbers of birds at the colony in early June was likely resulted from the departure of both breeding (pre-laying stage) and non-breeding birds. Another decline at the end of September was most likely a consequence of the departure of non-breeding birds only. In general, as the season progressed there were fewer petrels per night, and they arrived later. The number of birds returning to the colony increased with increasing wind speeds and birds arrived earlier when winds were stronger. High wind speeds facilitate movement between breeding and foraging grounds for this pelagic species. A sampling period of 1 h from the arrival of the 1st bird provides sufficient information to discern definite patterns in numbers throughout the year.