Table 1 Summary of control and seismic model results.

From: Seismic surveys reduce cetacean sightings across a large marine ecosystem

 

Survey Activity

Month

Depth

Slope

SST

Chl-a

Spatial

Interaction

Inactive

Active

(1)

Control

Baleen Whale

↓ (87)

↓ (88)

+

+

+

+

+

+

 

(2)

Control

Toothed Whale

↓ (29)

↓ (53)

+

 

+

 

+

+

 

(3)

Seismic

Baleen Whale

ns

NA

+

 

+

  

+

+*

(4)

Seismic

Toothed Whale

↑ (35)

NA

+

+

  

+

+

 
  1. For the ‘survey activity’ covariate, a ↓ symbol indicates a significant negative model coefficient (P < 0.05), i.e. a significant decrease in cetacean sightings, a ↑ symbol indicates a significant positive model coefficient (P < 0.05) i.e. a significant increase in cetacean sightings, and ‘ns’ indicates a non-significant result. Reduction in sighting density (compared to the baseline) are presented in brackets. All other covariates retained in the best GEE-CReSS control and seismic models are indicated with a plus sign (+), and their effect on cetacean sightings densities are presented as partial residual plots in Supplementary Figs. S2 and S3. Control baleen whale model (1), control toothed whale model (2), seismic baleen whale model (3), seismic toothed whale model (4). For the control models, ‘survey activity’ included three levels; active, inactive, and control (no airgun activity on a non-seismic vessel), the level ‘control’ was used as the baseline. For the seismic models, the factor covariate ‘survey activity’ included two levels: active (airguns on operating on full-power on a seismic survey vessel), inactive (no airgun activity on a seismic survey vessel), the level ‘active’ was used as the baseline. The covariate ‘spatial’ denotes the spatial component consisting of x and y coordinates, the covariate ‘interaction’ indicates an interaction of the spatial component and survey activity (an asterisk * indicates a significant interaction variable).
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