Table 2 Comparison of mean dive parameters from two periods winter (March and April, whales BW1 to BW4) and spring (May, whales BW5 to BW9) from this study and from earlier data collected from bowhead whales in Disko Bay between 2001-2006, also reported in [2]

Data from this study:

Mean depth of U-dives >60 m (m)

Number of U-dives

143

77

**

Mean depth U-dives <60 m (m)

Number of U-dives

31

30

Max depth of U-dives (m)

Number of U-dives

342

184

**

Max depth of V-dives (m)

Number of V-dives

381

248

*

Vertical speed of U-dives; descent rate (ms^-1)

Number of U-dives

0.65

1.28

*

Vertical speed of U-dives; ascent rate (ms-1)

Number of U-dives

-0.68

-0.72

Vertical speed of V-dives; descent rate (ms-1)

Number of V-dives

0.45

0.30

Vertical speed of V-dives; ascent rate (ms-1)

Number of V-dives

-0.41

-0.27

Distance to seabed of V-dives (m)

Number of V-dives

106

230

Distance to seabed of U-dives (m)

Number of U-dives

127

77

*

Overall dive rate (dives hr-1)

Deployment duration

2.07

4.76

***

Dive rate of V-dives (dives hr-1)

Deployment duration

1.15

0.95

Dive rate of U-dives (dives hr-1)

Deployment duration

1.86

4.75

***

Bottom time of U-dives (dives hr-1)

Number of U-dives

1092

499

***

Proportion of time spent in the bottom of U-dives (%)

Number of U-dives

38

33

Duration of all dives below 20 m (min)

Number of U-dives

19.7

9.5

***

Data from [2], n = 6 in winter (April) and 8 in spring (May):

April

May

Mean depth of all dives below 12 m (m)

Deployment duration

81

68

Max depth of all dives below 12 m (m)

Deployment duration

238

233

Maximum duration of all dives below 12 m (min)

Deployment duration

39.0

21.6

***

Duration of all dives below 12 m (min)

Deployment duration

15.1

9.7

**