https://doi.org/10.82144/e0b19e8e https://seamap.env.duke.edu/dataset/115 https://www.gbif.org/dataset/cb6a64b7-d290-4b7c-a23c-052882c96d83 https://obis.org/dataset/2c2569fd-7290-4b3d-8b56-7fe9902a2084 Roderick Hobbs National Marine Mammal Laboratory Primary contact Rod.Hobbs@noaa.gov OBIS-SEAMAP Marine Geospatial Ecology Lab, Duke University

A328 LSRC building Durham NC 27708 US

seamap-contact@duke.edu https://seamap.env.duke.edu OBIS-SEAMAP Marine Geospatial Ecology Lab, Duke University

A328 LSRC building Durham NC 27708 US

seamap-contact@duke.edu https://seamap.env.duke.edu distributor Roderick Hobbs National Marine Mammal Laboratory Primary contact Rod.Hobbs@noaa.gov owner 2025-07-31 eng Original provider: National Marine Mammal Laboratory Dataset credits: National Marine Mammal Laboratory Abstract: Aerial surveys was conducted in 1997 progressing from east to west, to estimate abundance of the Southeast Alaska (SEA, 9,844 km survey effort), Gulf of Alaska (GOA, 10,127 km survey effort), and Bering Sea (BS, 7849 km survey effort) harbor porpoise stocks. In addition, 1355 km of survey effort during a Cook Inlet beluga survey were analyzed to add to the coverage for the GOA stock. Data from an independent observer concentrating on the trackline was used to estimate perception bias. Significant differences in g(0) and effective strip width (ESW) were found between the survey conducted in 1997 and the 1998 and 1999 surveys, therefore 1997 was treated separately. In both analyses, g(0) was dependent on visibility reported by observers, and in the 1997 data ESW was dependent as well. The 1997 survey included the inland waters of southeastern Alaska and the eastern Gulf of Alaska from Dixon Entrance to Cape Suckling Occurrence GBIF Dataset Type Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_type.xml Observation GBIF Dataset Subtype Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_subtype.xml Marine Biology Visual sighting Aircraft Sightings harbor porpoise survey aerial survey cetacean N/A Although the previous harbor porpoise surveys (1991- 1993) used a vessel platform for the inside waters of Southeast Alaska (Dahlheim et al. 1992, 1993, 1994), the current survey was conducted entirely from aircraft. This work is licensed under a Creative Commons Attribution Non Commercial (CC-BY-NC) 4.0 License. https://seamap.env.duke.edu/dataset/115 Oceans,Alaska,Eastern Alaska,Gulf of Alaska,Dixon Entrance,Cape Suckling -143.9533 -131.0048 60.133 54.4542 1997-05-28 1997-07-28 Scientific names are based on the Integrated Taxonomic Information System (ITIS). species Balaenoptera physalus Fin whale order Cetacea Cetaceans species Eschrichtius robustus Gray whale species Eumetopias jubatus Steller sea lion species Lagenorhynchus obliquidens Pacific white-sided dolphin species Megaptera novaeangliae Humpback whale genus Mesoplodon Beaked whales species Orcinus orca Killer whale species Phoca vitulina Harbor seal species Phocoena phocoena Harbor porpoise species Phocoenoides dalli Dall's porpoise species Physeter macrocephalus Sperm whale A 3-year survey began in 1997 to complete a new abundance estimate by 1999. This survey will also include an abundance estimate for Dall’s porpoise (Phocoenoides dalli). Once the 3 years of surveys are completed, the data will be used to estimate annual abundance of harbor porpoise and Dall’s porpoise, which is one of the key pieces of information needed to manage marine mammal-fishery interactions, as required under the Marine Mammal Protection Act. notPlanned Roderick Hobbs National Marine Mammal Laboratory Primary contact Rod.Hobbs@noaa.gov NA NA NA Roderick Hobbs owner NA zd_115 2025-07-31T14:05:23-04:00 dataset Hobbs, R. 2004. NMML Small Cetacean Aerial Survey 1997. Version 1.0.0. Dataset published in OBIS-SEAMAP. https://doi.org/10.82144/e0b19e8e. OBIS-SEAMAP Dataset Page UTF-8 Interactive map https://seamap.env.duke.edu/dataset/115 FGDC Metadata UTF-8 XML https://seamap.env.duke.edu/dataset/115/fgdc EML Metadata UTF-8 XML https://seamap.env.duke.edu/dataset/115/eml OBIS-SEAMAP zd_115 zd_115