Activity sensor data:
With an enabled activity logging option, the collar is able to log the activity in one or two axis. Activity loggers determine the
acceleration of the collar whereby the activity of the tracked wildlife is monitored. Stored are counts per unit. So the activity is seized by a relativ value data to accelaration in X and Y direction.
8 times per second the acceleration of the collar will be measured. After every 5 minutes this value will be normed to a value between 0 and 255 and stored. 0 means no
activity during the 5 minute interval, 255 means maximum activity. The time stamp has an resolution of one minute absolute. In order to class the measured activity value to the kind of activity of the tracked
animal, the relation of both has to to be figgered out befor or after the study by live watching.
Wildlife activity data examples:
In figure 1 the activity data (two axis logging) and the ambient air temperature (red line) of a tracking study on a wolf from March to October 2002 in Finland are
presented. Alltogether 39539 datasets are taken. The graph is plotted by the GPS-Plus software. For further evaluation it is easy to zoom to the region of interest (figure 2).
Fig. 1: Activity (blue and green symbols) and temperature (red line) data taken by sensors in the GPS-GSM collar from March to October 2002 (n=39539 data sets-values each)
In order to learn about the daily actions of the wolf, in figure 0 his activity is plotted from 8 -
13 September. The red line shows the daily temperature developement, with maximum at midday and minimum at neight. The wolfs activity shows a clearly pattern: relative hight
activity at neight and less activity at daylight.
In figure 2 a detail view of the figure 1 is presented.
Fig. 2: Activity of the wolf in x (blue symbols) and y-axis (green symbols) and ambient air temperature (red line), from 8-13 September 2002
The activity of the bear â€śBlomeâ€ť from a continous study in Sweden, has been monitored by a
two axis activity logger. At least 47520 data sets have been stored on the collar in 2003 (fig.3).
Fig. 3: Activity data of Blome in x- and y direction (blue and green symbols) and temperature data (red line), April 13 to September 25, 2003 (n=47520 data sets each)
Figure 4 shows a cut of figure 3, the bearâ€™s activity from the July 21 to 24. The red line
shows the progress of the daily temperature with no big differences between midday and night, because of the midnigth sun. The bearâ€™s activity shows a strict pattern: high activity
at the evening and wheras the morning and lower activity at the hours around midday.
Fig. 4: Detail of Blomes activity in x (blue symbols) and y-axis (green symbols) and ambient air temperature (red line), from July 21 - 24, 2003