Table 1 Descriptive statistics of clusters. Delaunay distances between clusters’ centroids correspond to the length of edges obtained by Delaunay triangulation on synchronous clusters’ centroids.

From: Seabird distribution patterns observed with fishing vessel’s radar reveal previously undescribed sub-meso-scale clusters

Variable

Median

Mean

Min

Max

Mean of coefficients of variation

Sd. of coefficients of variation

Maximum possible given the radar range of 30 km

Delaunay distances between clusters’ centroids (km)

12.9

14.3

2.0

50.8

—

—

60 km

Clusters’ area (km2)

21.9

43.2

0.02

505.2

0.8

0.4

2,827 km2

Equivalent diameter of clusters (km)

4.8

5.8

0.2

24.5

0.4

0.2

60 km

Maximum extent of clusters (km)

9.2

10.6

0.9

39.5

0.4

0.2

60 km

Delaunay distances between echoes in clusters (km)

2.1

2.3

0.4

8.5

0.5

0.1

60 km

Distance to the boat at starting point (km)

12.0

13.0

0.3

29.5

—

—

30 km

Distance to the boat at ending point (km)

11.9

12.9

0.1

29.5

—

—

30 km

Translation of clusters’ centroids (km)

3.2

3.8

0.03

36.9

—

—

60 km

Duration of clusters (h:min:s)

00:03:30

00:05:09

00:00:30

01:20:04

—

—

—

  1. Clusters’ areas, equivalent diameters, maximum extents and Delaunay distances between echoes were averaged for each cluster during its lifetime. Coefficients of variation of the four previous metrics (along clusters’ tracks) were calculated for each cluster. The mean and standard deviation of all coefficients of variation are reported for the four metrics (columns 6 and 7). Distances to the boat at starting and ending points refer to the distance of clusters’ centroids to the boat at the beginning and at the end of clusters’ tracks. Translations of clusters correspond to the distance between their starting and ending centroids’ locations.
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