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[1] We calibrated SPARROW (Spatially Referenced Regression on Watershed Attributes) surface water-quality models using measurements of total nitrogen and total phosphorus from 37 sites in the 13,900-km 2 Waikato River Basin, the largest watershed on the North Island of New Zealand. This first application of SPARROW outside of the United States included watersheds representative of a wide range of natural and cultural conditions and water-resources data that were well suited for calibrating and validating the models. We applied the spatially distributed model to a drainage network of nearly 5000 stream reaches and 75 lakes and reservoirs to empirically estimate the rates of nutrient delivery (and their levels of uncertainty) from point and diffuse sources to streams, lakes, and watershed outlets. The resulting models displayed relatively small errors; predictions of stream yield (kg ha À1 yr À1 ) were typically within 30% or less of the observed values at the monitoring sites. There was strong evidence of the accuracy of the model estimates of nutrient sources and the natural rates of nutrient attenuation in surface waters. Estimated loss rates for streams, lakes, and reservoirs agreed closely with experimental measurements and empirical models from New Zealand, North America, and Europe as well as with previous U.S. SPARROW models. The results indicate that the SPARROW modeling technique provides a reliable method for relating experimental data and observations from small catchments to the transport of nutrients in the surface waters of large river basins.

The marine habitat exploited by black-browed Diomedea melanophrys and grey-headed albatrosses D. chrysostoma breeding at Campbell Island, New Zealand, was studied using satellite telemetry. Data were analysed in relation to the bathymetry and sea-surface temperature of the foraging zones. Black-browed albatrosses spent 55% of their time on the Campbell Plateau but also carried out long foraging tnps to the Polar Front and Antarctic Zone at a distance of over 2000 km. They relied heavily on juvenile Micrornesistius australis, a schooling fish, during foraging trips to the shelf but over oceanic waters the squid Martialia hyadesi was the main prey taken. Grey-headed albatrosses spent 71 % of their time foraging over the deep waters of the Polar Frontal Zone where M. hyadesicomprised over 90% of the mass of prey taken. No satellite-tracked birds fed over the shelf, but data from the duration of foraging trips and dietary analysis suggests that shelf-feeding is important for this species. Significant inter-species differences in the time spent in neritic and oceanic zones show that blackbrowed albatrosses are reliant primarily on shelf resources while grey-headed albatrosses are primarily oceanic feeders. In addition, the 2 species overlapped little in the zones used over oceanic waters, with black-browed albatrosses feeding in more southerly waters than grey-headed albatrosses. However, both species feed on M. hyadesi when foraging in association with the Polar Front.

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