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The remaining five Coenocorypha snipes are restricted to remote islands in the New Zealand archipelago, so their ecology is difficult to study directly. To ascertain habitat types and ecological interactions across the different taxa and locations, we measured the Δ13C and Δ15N of feathers from known individual Auckland Island snipe C. aucklandica aucklandica (Adams I., n = 12; Enderby I., n = 4; Rose I., n = 8), Chatham Island snipe C. pusilla (Rangatira, n = 10), and Campbell Island snipe (Coenocorypha undescribed sp.; n = 1). Data for Snares snipe C. a. huegeli (North East I., n = 1) came from the literature. Developmental stage (nestling, juvenile, adult) and sex were statistically indistinguishable. Although significant differences in Δ13C occurred between islands, the overall range was small (mean ± standard deviation, -22.7 ± 0.9‰). The restricted Δ13C show that the snipe we sampled occupied a consistent habitat regardless of taxa, island size, and disturbance history. Conversely, the range in Δ15N was large at c. 18.5‰ and implied occupation of sites with a wide range of nutrient status. The δ15N from Adams I. (mean 5.9 ± 1.7‰) was much lower than the other islands (mean 19.2 ± 2.0‰) and could only be explained by including a 15N-depleted site not affected by seabirds or seals. Auckland Island snipe therefore integrate seabird breeding and nonbreeding areas as well as inhabiting locations with seals and high seabird densities. Consequently, Coenocorypha snipes provide connectances between marine animals on land and the wider terrestrial environment and so may be considered for (re)-introduction to predator-proof mainland New Zealand restoration sites. [ABSTRACT FROM AUTHOR]

Marine nitrogen (N) has been traced into terrestrial and freshwater food chains at petrel (Aves: Procellariiformes) colonies on the South Island of New Zealand, but the effects of N or other marine-derived nutrients on the productivity of mainland forests are unknown. Mean ring widths in matai (Prumnopitys taxifolia; n = 3) and rimu (Dacrydium cupressinum; n = 2) trees growing in a Westland petrel (Procellaria westlandica) colony were 0.9-1.4 mm yr-1, similar to ring widths reported elsewhere. However, series of much wider rings in cores showed that trees in a petrel colony can experience periods of accelerated growth. δ15N values of whole wood were, at 3.2-11.1‰, significantly enriched in comparison to other temperate forest trees. The highest δ15N values were at the cambial and pith ends of different cores, so isotopic fractionation during N remobilisation is unlikely to have been significant. The radial extent of 15N enrichment suggests that petrels have bred at the site since at least the mid 18th century. [ABSTRACT FROM AUTHOR]