Table 2 Results of fitting a linear mixed-effects model to determine the level of baseline-corrected cortisol in earplug of large baleen whales (1900–1999) given sex, age, sex/age interaction, and number harvested over 5-year intervals

From: Baleen whale cortisol levels reveal a physiological response to 20th century whaling

Variable

Coefficient

SE

Wald z

P-value

Percent cortisol above baseline

Sex (female versus male)

−0.461

12.700

−0.04

0.971

Age category (years)

    

  11–24.9

9.789

3.288

2.98

0.003

  ≥ 25

19.054

5.949

3.20

0.001

Sex/age category interaction

−9.880

3.4424

−2.89

0.004

Number of whales harvested each year

0.005

0.002

3.18

0.001

  1. SE, standard error
  2. Age = <11, 11–24.9, ≥ 25 years. The reference values were sex = male, age category = <11 years. Significant predictors are those with P values ≤ 0.05
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