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Assessing the suitability of non-invasive methods to monitor interspecific interactions and breeding biology of the South Georgian diving petrel (Pelecanoides georgicus)

Notornis, 64 (1), 13-20

J.H. Fischer; I. Debski; G.A. Taylor; H.U. Wittmer (2017)

Article Type: Paper

We assessed the impact of interspecific interactions on the breeding success of the South Georgian diving petrel (Pelecanoides georgicus; SGDP), a Nationally Critical seabird species, by monitoring 20 burrows at Codfish Island (Whenua Hou), with remote cameras. Additionally, we tested the utility of remote cameras to study the breeding biology and activity patterns of the SGDP by pairing 5 remote cameras with RFID readers. We recorded 7 different species at SGDP burrow entrances. The common diving petrel (P. urinatrix) likely caused two monitored burrows to fail. These results suggest that remote cameras are useful tools to study such interactions. However, the cameras had extremely low SGDP detection rates (mean = 10.86%; se = 7.62%) when compared to RFID readers. These low detection rates may be explained by the small body size and the speed at which SGDPs enter/leave burrows. Therefore, remote cameras, or at least the model and setup we used, appear unsuitable to study breeding biology and activity patterns in this seabird species.

Vagrant and extra-limital bird records accepted by the Birds New Zealand Records Appraisal Committee 2015-2016

Notornis, 64 (2), 57-67

C.M. Miskelly; A.C. Crossland; P.M. Sagar; I. Saville; A.J.D. Tennyson; E.A. Bell (2017)

Article Type: Paper

We report Records Appraisal Committee (RAC) decisions regarding Unusual Bird Reports received between 1 January 2015 and 31 December 2016. Among the 113 submissions accepted by the RAC were the first New Zealand records of northern fulmar (Fulmarus glacialis), Herald petrel (Pterodroma heraldica), red-footed booby (Sula sula), laughing gull (Larus atricilla) and magpie-lark (Grallina cyanoleuca), the first breeding records for Australian wood duck (Chenonetta jubata) and glossy ibis (Plegadis falcinellus), and the second accepted records of shy mollymawk (Thalassarche cauta cauta), great shearwater (Puffinus gravis) and Cape gannet (Morus capensis). Other notable records included a pair of white-winged black terns (Chlidonias leucopterus) breeding in the Mackenzie basin, and the first record of pukeko (Porphyrio melanotus) from the Snares Islands. In addition, notable influxes of brown booby (Sula leucogaster) and great frigatebird (Fregata minor) occurred during 2015-16.

Bill trait variation in kākāpō, Strigops habroptilus (Gray): differences between contemporary and historical birds

Notornis, 64 (1), 1-12

L.J. Gray; A. Digby; D.K. Eason (2017)

Article Type: Paper

Museum study-skins are an important though under-utilised resource for studying the biology of endangered birds. This study compares the bill and cere morphology of female and male kākāpō (Strigops habroptilus) from three provenances: 1) “historical wild-origin” museum specimens collected from the North and South islands of New Zealand over 100 years ago; 2) the “modern wild-origin”, predominantly ex-Stewart Island Kākāpō Recovery Programme (KRP) founder population; and 3) the “modern non-wild” descendants of the founder population raised and maintained under the conservation management of the KRP. Bill length and gape was found to be smaller in the historical wild-origin birds than in the two contemporary groups. In comparison, historical wild-origin male kākāpō had larger ceres than both contemporary groups. As bird bills can show rapid morphological adjustment to diet over generational time scales, we evaluate whether bill size differences measured could be due to differences in the nutritional environments experienced by the birds either across their life-times or over recent evolutionary time. We also discuss whether regional variation in sexual selection might account for the provenance related variation in cere size.

The changing relative abundance of grey duck (Anas superciliosa) and mallard (A. platyrhynchos) in New Zealand

Notornis, 64 (4), 211-228

M. Williams (2017)

Article Type: Paper

Change in the relative abundance of grey duck (Anas superciliosa) and mallard (A. platyrhynchos) in New Zealand, from 1950 to the present day, is summarised from trapping records, hunters’ kills, and field studies. Mallards achieved numerical ascendency over grey duck throughout most of New Zealand by the late 1970s, merely 20 years after the cessation of mallard releases by historic acclimatisation societies. Post-1990, the relative abundance of mallard in almost all districts, as recorded from hunters’ kills, appears to have stabilised at 90%, or higher. Uncertainty about hunters’ and the public’s ability to discriminate between grey ducks, their hybrids with mallard, and variably-plumaged mallard females is demonstrated and most modern (post-1990) records of relative species abundance must be regarded as quantitatively suspect. Ducks identified as grey ducks by hunters are now a relative rarity throughout New Zealand, except in Northland and West Coast. Post-1990 duck trapping in North Island indicates that grey ducks, where reported, are patchily rather than generally distributed. The absence of genetically-validated criteria for discriminating ducks of grey duck x mallard hybrid ancestry continues to confound field identifications of both species.

A survey of Fiordland crested penguins / tawaki (Eudyptes pachyrhynchus) from Cascade River to Martins Bay, South Westland, New Zealand, 2014

Notornis, 64 (4), 206-210

R. Long (2017)

Article Type: Paper

A survey of Fiordland crested penguin/tawaki, Eudyptes pachyrhynchus, breeding colonies between Cascade River and Martins Bay, South Westland, was undertaken from August to September 2014 to obtain an accurate population estimate for the area. A total of 835 nests was found, making this one of the major breeding locations for the species. This total represents a minimum estimate as tawaki nests are spread through large areas of dense forest and are very difficult to locate, and so count accurately. A total of 150 nests was observed in previous surveys of the same location. This dramatic difference in results (835 vs. 150) is attributed to a difference in survey methods and the surveyor’s familiarity with the breeding area, not a population increase. Given these results and the difficulty involved in locating tawaki, it is likely that the species’ overall population size has been significantly underestimated.

Weights and measurements of Anas superciliosa in New Zealand

Notornis, 64 (3), 162-170

M. Williams (2017)

Article Type: Paper

Weights and body measurements from 258 male and 203 female adult (>1 year) and juvenile (<1 year) grey duck (Anas superciliosa), were collected from freshly-shot specimens in May 1974 and 1975 at sites in North Island, New Zealand. Mean weights of adult (1069 g) and juvenile (1035 g) males were significantly greater than those of adult (967 g) and juvenile (926 g) females. Assessment of body mass relative to skeletal size using a mass-size index (weight/tarsus2 ) did not detect any significant differences between any sex and age categories. Body measurements were of bill length and width, tarsus and middle-toe-and-claw lengths, and wing and tail lengths, and presented for each sex and age class. For every character measured, mean lengths for juvenile males were significantly longer than for juvenile females, and those for adult males significantly longer than for adult females. Within each sex, only mean wing and tail measurements from adults were significantly longer than those from juveniles. Significant differences in field weights and some body measurements between New Zealand and Australian A. superciliosa were identified.

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