Breeding ecology of three subantarctic snipes (genus Coenocorypha) | Notornis and Birds New Zealand

[摘要] Information on the breeding ecology of Auckland Is snipe (Coenocorypha aucklandica aucklandica), Antipodes Is snipe (C. aucklandica meinertzhagenae) , and Campbell Is snipe (Coenocorypha undescribed sp.) is summarised. Auckland Is snipe laid between Sep and Jan (peak late Nov), whereas Antipodes Is snipe laid from Aug to early Nov, with a 2nd pulse of breeding from late Jan to Mar. The 5 breeding events recorded for Campbell Is snipe were from clutches estimated to have been commenced between 11 Nov and 8 Jan. All 3 taxa laid 2 large eggs (each 19-22% of female body weight) in nests that were well concealed amid dense vegetation. Chicks left the nest soon after hatching, with each chick cared for by a single adult. Exceptions to this were adult Auckland Is snipe seen with 2 or 3 young chicks on 3 occasions. Chicks remained with adults until down-free and capable of flight. The only notable differences from the more thoroughly-studied Snares Is snipe (C.aucklandica huegeli) and Chatham Is snipe (C. pusilla) were the earlier breeding by Antipodes Is snipe, and its bimodal breeding season. Snipe were encountered more frequently on the Auckland Is (0.6 person–h-1 of walking on Adams I) than on Antipodes I (0.2 person–h-1) and this was also reflected in the frequency with which breeding events were recorded. We suggest that the impact of house mice (Mus musculus) on the invertebrate food supply available for snipe is the most plausible explanation for the much lower abundance of snipe on Antipodes I.

[学科分类] 动物科学

[关键词] Antipodes Island;Auckland Island;breeding ecology;Campbell Island;Coenocorypha aucklandica;New Zealand Snipe;Robert Alexander Falla