Table 1.

Variables measured and type of behavioral response (*) during video analysis with corresponding description.

Measurement	Description
FID	Measured at the moment of first reaction, from the most forward point of each treatment (i.e. the middle of the snout in the shark model) to the tail or eye of each fish, depending on which way the fish was facing. In some cases fish became aware and wary of the treatment approaching, known as distance of first alert82, sometimes changing the direction they were facing prior to flight, but FID was always measured the instant the fish began to flee
Total length of prey fish (body length)	The length was measured when the fish was fully extended parallel and as close to the camera as possible
Treatment size	The size of treatment was included as an explanatory variable where: Shark: 170 cm, Snorkeler: 180 cm, Turtle: 65 cm, Pipe: 81 cm and Perspex: 81 cm This variable was included in the model to account for the difference in size between the threat treatments and the controls
No. of fish	Whether the fish was swimming as an individual or within a school. A school was defined as three or more fish swimming closely together and synchronizing movements. To analyze the escape response of a school, three individuals were haphazardly selected for measurement and the average value of these measurements used to represent the behaviour of the school
Vertical height from benthos (VHB)	Measured from the lowest point of the fish to the nearest benthos below the fish. This measurement was taken three times: nine, six, and two seconds prior to FID. If the fish was not within frame for those nine seconds prior to FID the measurements were taken three, two and one second prior to FID. The mean of the three measurements was included in statistical models
Speed of flight	The difference between mean swimming speed of a fish prior to approach of the treatment and speed after the arrival of the treatment. This was calculated by measuring the distance of movement every three seconds (three, six and nine seconds) prior to treatment approach and dividing it by the time (three seconds). The swimming speed of flight was calculated using position coordinates to measure the distance40 from the flight response to the time when the fish was no longer visible or hiding
C-turn*	A 90°–180° turn before swimming away out of the field of view of camera
Flight*	A fish swam away from the treatment and out of the field of view of the camera in the direction it was already facing
Hide*	Swimming into a crevice or hole in the reef
No response*	No change in behaviour during the approach of the treatment