Dataset
OBIS-SEAMAP Open in mapper Explore occurrences
Original provider: National Marine Mammal Laboratory Dataset credits: National Marine Mammal Laboratory Abstract: On 15 August 1991, as part of a larger study, Alaska harbor porpoise (Phocoena phocoena) abundance was investigated during an aerial survey of waters off southeastern Alaska. A Twin Otter was used to fly a single sawtooth trackline 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.
Citation: Goetz, K. and J. Waite. 2004. NMML Harbor Porpoise Aerial Survey, SE Alaska, 1991 . Version 1.0.0. Dataset published in OBIS-SEAMAP. https://doi.org/10.82144/50bf3146.
Published: October 07, 2025 at 19:01
URL: http://ipt.env.duke.edu/resource?r=zd_142
Kimberly Goetz
Duke University
Janice Waite
National Marine Mammal Laboratory
OBIS-SEAMAP
Marine Geospatial Ecology Lab, Duke University
| Field | Missing | Invalid | |
|---|---|---|---|
| coordinateUncertaintyInMeters | 3 |
|
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| maximumDepthInMeters | 3 |
|
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| minimumDepthInMeters | 3 |
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The OBIS data quality flags are documented at https://github.com/iobis/obis-qc.
| Flag | Dropped | Records | |
|---|---|---|---|
| NO_DEPTH | 3 |
|