AFSC/NMML: Southeast Alaska Cetacean Vessel Surveys, 1991 - 2012

In 1991, NMML initiated cetacean studies with vessel coverage throughout inland waters of Southeast Alaska. Between 1991 and 1993, line-transect methodology was used to: 1) obtain population estimates of both harbor porpoise and Dalls porpoise, 2) establish a baseline for detecting trends in porpoise abundance, and 3) define porpoise distributional patterns and seasonality. Three line-transect surveys were carried out each year spanning spring, summer, and fall. To update abundance and trends for both harbor porpoise and Dalls porpoise, NMML once again initiated line-transect surveys in 2006 (spring and summer), 2007 (spring, summer and fall), 2010 (summer and fall), 2011 (summer and fall), and 2012 (summer) using methods comparable to those used in the early 1990s.

Assess cetacean distribution, group size, seasonal occurrence, abundance and population trends.

Loaded by FGDC Metadata Uploader, batch 8489, 04-06-2016 15:37

The following FGDC sections are not currently supported in InPort, but were preserved and will be included in the FGDC export:

- Taxonomy (FGDC:taxonomy)

The user is responsible for the results of any application of this data for other than its intended purpose.

NOAA denies liability if the data are misused.

Data is available at http://data.nodc.noaa.gov/cgi-bin/iso?id=gov.noaa.nodc:0140931

There are no legal restrictions on access to the data. They reside in public domain and can be freely distributed.

User must read and fully comprehend the metadata prior to use. Applications or inferences derived from the data should be carefully considered for accuracy. Acknowledgement of NOAA/NMFS/AFSC, as the source from which these data were obtained in any publications and/or other representations of these, data is suggested.

Excel

This data includes surveys conducted in the years 1991 - 1993, 2006, 2007, 2010, 2011 and 2012. The surveys conducted in 1991-1993 used a computer program developed by Jim Cubbage. In the 2000's, survey data was collected with Wincruz (Windows Real Time Sighting-Effort Event Logger developed by Robert Holland at Southwest Fisheries Science Center). Most years used the NOAA ship John N. Cobb, but after it was no longer available in 2008, four different charter vessels were used to conduct our surveys: the F/V Steller (commercial fishing vessel) in July 2010; the F/V Northwest Explorer in September 2010; the R/V Medeia (patrol vessel operated by the Alaska Department of Fish and Game) in June and September 2011; and the R/V Aquila in July 2012. In the early 1990's, six observers were used to collect the data. For the 2006 and 2007 surveys, four observers were used, in 2010, 5 observers were used, and in 2011 and 2012, 6 observers were used. Because of the differences in the number of observers, the rotation schedule (time spent at each station) changed over the years.

Accuracy was ensured by reviewing and editing the data in the field on a daily basis. For the surveys in the 2000's, post cruise processing included data extraction and error checking using customized software (writen by Paul Wade, National Marine Mammal Laboratory). Tracklines and sightings were plotted in ArcMap to check for accuracy.

Accuracy was ensured by reviewing and editing the data in the field on a daily basis. For the surveys in the 2000's, post cruise processing included data extraction and error checking using customized software (writen by Paul Wade, National Marine Mammal Laboratory). Tracklines and sightings were plotted in ArcMap to check for accuracy.

IT Security and Contingency Plan for the system establishes procedures and applies to the functions, operations, and resources necessary to recover and restore data as hosted in the Western Regional Support Center in Seattle, Washington, following a disruption.

Methods are described in http://fishbull.noaa.gov/1133/dahlheim.pdf.