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Table 3 Comparison of dive characteristics during periods when the sonar tag was not pinging (NP) vs. pinging (P)

From: Development of an animal-borne “sonar tag” for quantifying prey availability: test deployments on northern elephant seals

Dive metric

Seal #1

Seal #2

Seal #3

Seal #4

Maximum depth

NS 0.200

NP > P** 0.182

NP > P*** 0.353

NS 0.080

Dive duration

NS 0.242

NP > P*** 0.231

NP > P*** ° 0.338

NS 0.083

Bottom time

P > NP* 0.317

NP > P*** ° 0.334

NP > P*** 0.317

NS 0.056

Descent rate

P > NP* 0.325

NP > P** 0.182

NS 0.129

NP > P** ° 0.123

Ascent rate

NS 0.175

NS 0.123

NP > P*** 0.297

NS 0.047

Post-dive interval

NS 0.133

NS 0.143

NP > P*** 0.228

NS 0.040

# Inflections descent phase

NS 0.033

NS 0.021

NS 0.021

NS 0.010

# Inflections bottom phase

NP > P*** 0.467

NP > P*** 0.299

NS 0.124

NS 0.059

# Inflections ascent phase

NS 0.050

NS 0.042

NS 0.028

NS 0.024

  1. Kolmogorov-Smirnov tests were used to compare the distribution of these metrics comparing all dives made by each seal with the system pinging relative to when it was not. Table entries provide the Kolmogorov-Smirnov test statistics and for comparisons where dive metrics differed significantly indicate whether the metric was greater with the system pinging (P > NP) or not pinging (NP > P) and indicate the significance level. Kolmogorov-Smirnov tests were also conducted on the average of metrics for all dives conducted during a pinging or non-pinging interval. The small number of such intervals limits the power of these tests, which mostly found non-significant differences, other than three tests (denoted via °) where differences were significant at the p < 0.05 level
  2. NS non-significant
  3. *p < 0.05; **p < 0.01; ***p < 0.001