NMML Harbor Porpoise Vessel Survey, SE Alaska, Spring 1991

Original provider:
National Marine Mammal Laboratory

Dataset credits:
National Marine Mammal Laboratory

Abstract:
In spring 1991, Southeast Alaska, Cook Inlet, and Bristol Bay, was surveyed for harbor porpoise (<i>Phocoena phocoena</i>) 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.