R: Data: Tow Track Polylines from Longspine Thornyhead Survey
towTracks
R Documentation
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.
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 Sciences2421, 60 pp.