IMIS

Dataset credit: Tagging of Pacific Predators (TOPP program) (http://www.topp.org/) Laysan (Phoebastria immutabilis) and black-footed (P. nigripes) albatrosses were studied using Microwave Pico-100 and Wildlife Computers SPOT 4 satellite transmitters. Birds were studied at Tern Island, French Frigate Shoals, Northwest Hawaiian Islands (23.872 N, 166.272 W) from December 2002 to March 2009. The primary tracking period covers the incubation and chick-brooding phases during each year. In nearly all cases, albatrosses were equipped with a tag for a single trip to sea. Trip durations range from 1-32 days in duration and some albatrosses traveled over 15,000 km in a single trip. The purpose of this research was to examine:

1. albatross distribution during breeding and post breeding phases,
2. characterize oceanic habitat of albatross habitat,
3. how both albatross species partition oceanic habitats,
4. commonalities in the distribution or physical features of their environment,
5. overlap and possible interaction with other TOPP organisms (e.g., elephant seals, tuna, sea turtles), and
6. highlight conservation priorities such as overlap with fisheries.

ARGOS points used for the dataset extent, inferred track and population of upstream OBIS archive were filtered according to McConnell et al. (1992), with a maximum velocity of 100 km/hr, or 27.8 m/s using the vmask function in the argosfilter R package (Frietas et al. 2008). This is the recommended method by the TOPP Seabird Research Team and others from the Global Procellariiform Tracking Workshop Report (Taylor 2004).

• Freitas, C., C. Lydersen, M.A. Fedak, and K.M. Kovacs. 2008. A simple new algorithm to filter marine mammal Argos locations. Marine Mammal Science, 24(2): 315-325.
• McConnell, B.J., C. Chambers and M.A. Fedak. 1992. Foraging ecology of southern elephant seals in relation to the bathymetry and productivity of the Southern Ocean. Antarctic Science, 4(04): 393-398.
• Taylor, F. 2004. Methods. In: J.P. Croxall (ed.). Global Procellariiform Tracking Workshop Report. BirdLife International, Cambridge, p. 3.