NMML Harbor Porpoise Aerial Survey, Cook Inlet, 1991 ...

• Main Authors: Goetz, Kimberly, Waite, Janice
• Format: Dataset
• Language: English
• Published: OBIS-SEAMAP 2021
• Subjects: Occurrence,Aircraft,Sightings,harbor porpoise,Phocoena phocoena,abundance,aerial survey,marine mammal survey,survey,marine mammal,cetacean; Observation; Occurrence; Phocoena phocoena; Alaska
• Online Access: https://dx.doi.org/10.15468/q42tgf; https://www.gbif.org/dataset/491a8670-4d9a-4266-a18c-8102042a1d2a

Original provider: National Marine Mammal Laboratory Dataset credits: National Marine Mammal Laboratory Abstract: On 1 and 2 August 1991, as part of a larger study, Alaska harbor porpoise ( Phocoena phocoena ) abundance was investigated during an aerial survey throughout the coastal waters of Cook Inlet. A Twin Otter was used to fly a single sawtooth trackline across Cook Inlet at an altitude of 152.2 m (500 ft) and at an airspeed of 185 km/h. Line-transect methodology was used, and only those observations made during optimal conditions were analyzed. Density of harbor porpoises was calculated using line transect estimates based on perpendicular distances of sightings to the cruise track of the airplane. On average, porpoise group size and density for Cook Inlet was 1.33 (SE = 0.33) and 0.54 groups/100 km2 (SE = 0.31). Purpose: Although harbor porpoises, Phocoena phocoena , are known to occur throughout Alaska waters, few estimates of abundance exist. In 1991, the National Marine Mammal Laboratory initiated ...