Recovery of reef shark populations invokes anti-predator behaviours in mesopredatory reef fishes on a coral reef

Natural experiments where populations of large predators have recovered following management initiatives offer insights into the potential for these animals to structure communities via consumptive and non-consumptive effects on their prey. Ashmore Reef, a coral reef off the coast of Western Australia, provides such an opportunity. Here, reef shark populations have increased significantly since the enforcement of a no-take MPA in 2008. This change has been accompanied by an increase in abundance of medium and large mesopredatory teleosts, but a decline in small mesopredatory teleosts.We explored whether these changes in abundance were accompanied by changes in anti-predator (non-consumptive) behaviours of mesopredators due to an increase in both acute and chronic risk of predation. We analysed videos from Baited Remote Underwater Video Systems (BRUVS) collected prior to enforcement of no-take status in 2004 and after enforcement and shark recovery in 2016 to quantify any changes in anti..., Data were provided from a subset of Baited Remote Underwater Video System (BRUVS) video recordings surrounding Ashmore Reef in 2004 (n=24) and 2016 (n=24). We analysed BRUVS videos collected prior to enforcement of no-take status in 2004 and after enforcement and shark recovery in 2016 to quantify any changes in anti-predator behaviours of small (<50 cm TL), medium (50-100 cm TL) and large (>100 cm TL) size classes of mesopredatory reef fishes. The dataset comprises behavioural measurements of the behaviours of these reef fishes. For a full description of the methods please see 'Recovery of Reef Shark Populations Invokes Anti-Predator Behaviours in Mesopredatory Reef Fishes on a Coral Reef' (Storm et al., Journal of Animal Ecology, 2025). The dataset has been analysed in R, for the code please see https://github.com/andieich/Ashmore_behaviour, , # Recovery of reef shark populations invokes anti-predator behaviours in mesopredatory reef fishes on a coral reef

[https://doi.org/10.5061/dryad.x95x69pvx](https://doi.org/10.5061/dryad.x95x69pvx)

## Description of the data and file structure

### Files and variables

#### File: clean\_data.csv

**Description:** 

Each row represents the observation (from when a fish entered to when it left the field of view) of one mesopredatory teleost. During each observation, the below variables were recorded:

##### Variables

* genus_species: Genus and species. (*Nominal*)
* size_class: Size class of each mesopredatory fish species. Each mesopredatory fish species was assigned one of three size classes: ‘small’ (≤50 cm TL), ‘medium’ (50–100 cm TL), and ‘large’ (>100 cm TL). (*Nominal*, *small/medium/large*)
* year: Year of BRUVS drop. (*Categorial, year*)
* shark_in_video: Whether a shark was in the video, yes or no. (*Binary, yes/no*)
* sec_investigating_circling: The seconds a fish in an obse...,