Pelagic distribution and abundance of seabirds in the PROBES area

The data were gathered in strip transects, generally 300 m wide and recorded in the data base as densities. Over that period, there has been a change in the method for recording flying birds.

Before the year 2000, most, if not all, data on flying birds were recorded continuously, which can result in an inflated number of birds recorded per unit area. After 2000, most flying birds were recorded with the snap-shot method. The data in this dataset were retrieved from the USGS maintained North Pacific Pelagic Seabird Database, version 2, which is expected to be on line by late 2014, which have not been adjusted for the change in recording methods.