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Seabirds vector selenium (Se) into terrestrial ecosystems in Antarctica and on tropical coral islands, but factors controlling distribution within affected soils are unknown, especially in temperate regions. At a Westland petrel (Procellaria westlandica) breeding colony on mainland New Zealand, the concentration of Se in petrel guano (3.6mg [kg.sup.-1]) exceeded soil parent material (0.8mg[kg.sup.-1]) and in all but two soil samples (range 1.2-4.2mg[kg.sup.-1]; n=52). External Se (Se not derived from parent material) accounted for 645 ± 9% (mean ± s.d.) of soil Se. Measurements were also made at a former seabird breeding site, and at a site with no Holocene seabird breeding. Median surface-soil Se concentrations (mg [kg.sup.-1]) were in the order burrow soil (2.6)> adjacent forest floor (2.2)> former breeding site (1.0) > control site (0.2), with significant differences between burrow soil and (1) the former breeding site and (2) the control site. In a linear regression model, soil pH, and [δ.sup.15]N were the only significant predictors of external Se in colony soil. The correlations are consistent with seabird input driving both the Se supply and increased sorptive uptake in an environment acidified by seabird guano. Despite the enhanced Se in colony soil, median foliage concentrations (tree fern 0.05 mg[kg.sup.-1], nikau 0.08 mg[kg.sup.-1]) were close to the accepted minimum for herbivore nutrition. Seabirds therefore contribute significant Se to breeding colony soils in temperate areas, but this is not necessarily transferred to plant foliage. Additional keywords: allochthonous, burrowing seabird, nutrient subsidy, seabird soil, trace element., Introduction Selenium (Se) is a trace element with an unusually narrow boundary between deficiency and toxicity (Fordyce 2007). It is often deficient in soils, but can be found at toxic [...]

Guano from breeding seabirds provides a large external source of nutrients to the soils of breeding colonies. However, little is known of guano P retention relative to N or the relative importance of guano and soil parent material as P sources. Soil profile N and P inventories (0-0.60 m, n = 4; 0-.36m, n = 1) and guano N and P concentrations were measured at a Westland petrel colony, and the parent material contributions of P were calculated using Ca, Al, Fe, Ti, and Zr as reference elements. Median inventories (0-0.60 m) were 1.49 kg N/[m.sup.2] and 332 x [10.sup.-3] kg P/[m.sup.2], the N result being similar to that from a seabird colony on peat soil where N retention was very low. Calculated parent material contributions were smallest (32-66% of soil P) when based on Ca and largest (47-102% of soil P) when based on Zr. Contributions were similar for Al, Fe, and Ti; Al (41-87% soil P) was selected for subsequent calculations. Regardless of the reference element, parent material therefore contributed a large part of soil P. Phosphorus in excess of parent material supply ([P.sub.excess]) was significantly correlated with soil C, implying that guano P is held primarily in organic form. The median soil N : P molar ratios were 9.6:1 based on total P and 11.2:1 based on [P.sub.excess], compared with ratios for Westland petrel guano of 4.1:1 (when birds were consuming fisheries waste) and 16.4:1 (when fisheries waste was replaced by fish). The similarity between soil and guano N : P ratios implies that both N and P are lost from soil at similar rates, although volatilisation of N would enrich soil drainage water in P. Calculations using guano deposition rates from the literature yielded P residence times of 4-15 years ([P.sub.excess]) and 11-41 years (total P), consistent with a highly dynamic soil system. Additional keywords: ecological stoichiometry, nutrient cycles, New Zealand, nutrient limitation, stable isotope, Westland petrel., Introduction Nitrogen (N) and phosphorus (P) are essential plant nutrients with contrasting biogeochemical behaviours. Although N can be fixed from the atmosphere, P comes mostly from soil parent material. Consequently, [...]

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]