1 Import data

## [1] 44321
## [1] 7
## 
## no feeding      start    feeding        end 
##      40684        637       2363        637
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   10.20   35.30   36.00   35.67   36.50   38.00
##           ptt               start                 end  nrow        duration
## 1 3962-Eistla 2016-08-24 17:12:00 2016-08-26 16:59:00   759  1.9909722 days
## 7  7925-Thora 2014-08-11 15:33:00 2014-08-16 07:43:00  1971  4.6736111 days
## 2  3965-Frida 2015-08-15 18:33:00 2015-09-11 04:02:00 23084 26.3951389 days
## 4     7617-15 2015-08-14 16:25:00 2015-08-15 07:03:00   339  0.6097222 days
## 5     7618-15 2015-08-14 17:37:00 2015-08-30 11:51:00  5668 15.7597222 days
## 3    3965-TDR 2013-08-13 14:41:00 2013-08-21 13:12:00  7782  7.9381944 days
## 6   7618-Mara 2014-08-11 16:15:00 2014-08-24 21:18:00  4718 13.2104167 days
##   STdrop daily_drop
## 1      7   3.515870
## 7     23   4.921248
## 2    155   5.872293
## 4      4   6.560364
## 5    129   8.185423
## 3     95  11.967457
## 6    224  16.956316

2 ST profile over time

## # A tibble: 7 × 3
##   ptt         counts_start counts_end
##   <fct>              <int>      <int>
## 1 3962-Eistla            7        737
## 2 3965-Frida           155      21499
## 3 3965-TDR              95       7154
## 4 7617-15                4        324
## 5 7618-15              129       5177
## 6 7618-Mara            224       3908
## 7 7925-Thora            23       1885
ST profiles over time. Red dots refer to feeding start.

Figure 2.1: ST profiles over time. Red dots refer to feeding start.

3 STP duration

STP duration (in days) per individual.

Figure 3.1: STP duration (in days) per individual.

4 Number of ST drops per individual

Histogram of the number of ST drops per individual over the entire recording period.

Figure 4.1: Histogram of the number of ST drops per individual over the entire recording period.

5 Number of daily ST drops per individual

Histogram of the number of daily ST drops per individual.

Figure 5.1: Histogram of the number of daily ST drops per individual.

Lots of daily drops for Mara but some might be located close to surface and not associated with feeding.

6 Boxplot of ST during feeding vs. no feeding

## # A tibble: 14 × 4
## # Groups:   ptt [7]
##    ptt         feed        mean    sd
##    <fct>       <fct>      <dbl> <dbl>
##  1 3962-Eistla no feeding  35.2 0.561
##  2 3962-Eistla feeding     34.1 0.434
##  3 3965-Frida  no feeding  35.8 1.49 
##  4 3965-Frida  feeding     32.9 4.50 
##  5 3965-TDR    no feeding  35.9 1.06 
##  6 3965-TDR    feeding     34.6 1.50 
##  7 7617-15     no feeding  35.7 0.949
##  8 7617-15     feeding     28.2 2.18 
##  9 7618-15     no feeding  36.3 0.833
## 10 7618-15     feeding     34.3 3.11 
## 11 7618-Mara   no feeding  35.1 2.59 
## 12 7618-Mara   feeding     27.7 5.69 
## 13 7925-Thora  no feeding  35.6 1.35 
## 14 7925-Thora  feeding     31.6 3.45
## 
##  Kruskal-Wallis rank sum test
## 
## data:  stp$stp and stp$feed
## Kruskal-Wallis chi-squared = 1640.9, df = 1, p-value < 2.2e-16
## [1] 32.00558
## [1] 35.76728

ST is differs significantly between feeding and no feeding events (p<0.001). Average ST during feeding event: 32.0 degrees. Average ST during no feeding event: 35.7 degrees.

Histogram of the number of daily ST drops per individual.

Figure 6.1: Histogram of the number of daily ST drops per individual.

Some remaining outliers for “Frida, Mara and Thora.”no feeding” events, need to clean that.

7 Boxplot of depth during ST drops

## # A tibble: 7 × 5
##   ptt           mean    sd   min   max
##   <fct>        <dbl> <dbl> <dbl> <dbl>
## 1 3962-Eistla 338.   260.    3.5  724 
## 2 3965-Frida  117.   160.    0    544.
## 3 3965-TDR    215.   191.    0    604 
## 4 7617-15       7.75  12.9   0     27 
## 5 7618-15      44.1   95.2   0    546 
## 6 7618-Mara   218.   257.    0   1010 
## 7 7925-Thora  238.   250.    0.5  756.
## [1] 161.2353
## [1] 0.7468544
## [1] 0.5595542
## [1] 0.430947
## [1] 0.1308635
Histogram of the number of daily ST drops per individual.

Figure 7.1: Histogram of the number of daily ST drops per individual.

Few dives up to 1000 m for Mara, is that possible?

8 Duration of ST events (in min)

## # A tibble: 7 × 5
##   ptt         min_dur max_dur mean_dur sd_dur
##   <fct>         <dbl>   <dbl>    <dbl>  <dbl>
## 1 3962-Eistla       3      14     7.14   4.88
## 2 3965-Frida        3     121    19.2   22.9 
## 3 3965-TDR          3      50    14.8    8.67
## 4 7617-15           5      12     7.75   2.99
## 5 7618-15           2     275    22.7   37.1 
## 6 7618-Mara         2     134     6.83  12.8 
## 7 7925-Thora        3     137    32.9   42.9

The max duration is pretty high for some individuals (275 min for #7618-15, more than 5h to recover from feeding), but the average durations are similar to the published paper in 2014. The very short durations might be water ingestion, need to check if the events occur at the surface to confirm that.

Duration of the ST events (in min) per individual.

Figure 8.1: Duration of the ST events (in min) per individual.

9 Inter-event duration (in h)

## # A tibble: 7 × 4
##   ptt         min_dur max_dur mean_dur
##   <fct>         <dbl>   <dbl>    <dbl>
## 1 3962-Eistla  0.117    17.4      5.19
## 2 3965-Frida   0.0167   44.0      3.72
## 3 3965-TDR     0.0167   12.4      1.69
## 4 7617-15      1.07      7.48     4.32
## 5 7618-15      0.0167   24.2      2.57
## 6 7618-Mara    0.0167   12.8      1.30
## 7 7925-Thora   0.0167   10.6      4.43
Duration of the inter-feeding events (in min) per individual.

Figure 9.1: Duration of the inter-feeding events (in min) per individual.