Hi. I am running the as.ltraj () function in adehabitat (v 1.4 under R 2.2.1)
but can't seem to correctly specify the burst argument. i.e., the ltraj
object returned consists of only one component, when in fact my data consist
of more than one burst of reloctions per animal. i've set up the data (xy,
date, id, burst) in list form following the example given in ?as.ltraj. to
simplify, following is a section of the data for the 65th animal in my list
dataset:

       x          y                       loctime      burst
  479347  5515636 2005-07-07 21:05:20 bird498
  479405  5515729 2005-07-07 21:12:00 bird498
  479397  5515740 2005-07-07 21:12:20 bird498
  479388  5515740 2005-07-07 21:13:15 bird498
  479398  5515724 2005-07-07 21:16:20 bird498
  479416  5515717 2005-07-07 21:20:00 bird498
  479387  5515670 2005-07-07 21:34:00 bird498
  479225  5515689 2005-07-08 10:04:25 bird499
  479251  5515692 2005-07-08 10:06:33 bird499
  479290  5515705 2005-07-08 10:08:31 bird499
  479327  5515701 2005-07-08 10:09:29 bird499
  479390  5515744 2005-07-08 10:20:03 bird499
  479363  5515734 2005-07-09 09:18:24 bird500
  479373  5515746 2005-07-09 09:20:00 bird500
  479372  5515745 2005-07-09 09:20:30 bird500
  479373  5515746 2005-07-09 09:20:50 bird500
  479391  5515715 2005-07-09 09:22:40 bird500
  479356  5515761 2005-07-09 09:28:11 bird500
  479270  5515806 2005-07-11 13:50:10 bird501
  479295  5515780 2005-07-11 13:55:15 bird501
  479311  5515770 2005-07-11 13:57:30 bird501
  479391  5515791 2005-07-11 14:05:10 bird501
  479403  5515784 2005-07-11 14:08:25 bird501

and the code i input for this animal is:

(mytr1 <- as.ltraj(myxy[[65]][1:2], date = myxy[[65]][3], id="animal65",
burst=myxy[[65]][4]))

i'm returned a list of class traj with only one component which identifies
the animal, concatenates all unique burst character strings, and gives the
total number of relocations.

the burst data in my dataset are of the form is.character. Does anyone know
what I'm doing incorrectly to be returned a list of only one component per
animal (where number of relocations is total number of relocations per
animal)? instead of the desired list with x components per animal (x =
number bursts) with associated number of relocations per burst?

Thanks in advance.

Tina Leonard
M.Sc. candidate
Department of Biology
Acadia University
Wolfville, NS
CANADA

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