NMML Harbor Porpoise Vessel Survey, SE Alaska, Spring 1991

In spring 1991, Southeast Alaska, Cook Inlet, and Bristol Bay, was
surveyed for harbor porpoise (Phocoena phocoena) from the NOAA John N. Cobb
using line transect methodology. The shipboard platform was 28.36 m (93 ft) in
length with a bridge height of 4.27 m (14 ft). To obtain data on seasonal
movements of porpoise, a limited number of transects were made in areas of
known porpoise concentrations. When a sighting was made, the following
variables were recorded: time, angle, number of reticles to the sighting, radar
distance (nm) to the shoreline at the same angle of the sighting, the species,
the count of the porpoise seen (best, high, and low), and the animal(s)
direction of travel. Search effort was recoded by noting the time and location
of the ship at the beginning and end of each transect.