towTracks {PBSmapping}

Data: Tow Track Polylines from Longspine Thornyhead Survey

Description

PolySet of geo-referenced polyline tow track data from a longspine thornyhead survey (2001).

Usage

data(towTracks)

Format

Data frame consisting of 4 columns: PID = primary polygon ID, POS = position of each vertex within a given polyline, X = longitude coordinate, and Y = latitude coordinate. Attributes: projection = "LL", zone = 9.

Note

In R, the data must be loaded using the data function.

Author(s)

Nicholas M. Boers, Staff Software Engineer
Jobber, Edmonton AB
Last modified Rd: 2008-09-03

Source

The longspine thornyhead (Sebastolobus altivelis) tow track spatial coordinates are available at the Pacific Biological Station (Fisheries and Oceans Canada, Nanaimo, BC V9T 6N7). The geo-referenced coordinates of the first 45 tows from the 2001 survey (Starr et al. 2002) are included here. Coordinates are recorded once per minute between winch lock-up and winch release.

References

Starr, P.J., Krishka, B.A. and Choromanski, E.M. (2002) Trawl survey for thornyhead biomass estimation off the west coast of Vancouver Island, September 15 - October 2, 2001. Canadian Technical Report of Fisheries and Aquatic Sciences 2421, 60 pp.

See Also

addLines, calcLength, clipLines, plotLines, PolySet, towData.