DOI: 10.5061/dryad.9zw3r22tr
title: Data from: Site-level field of view is associated with altered anti-predator responses in farming damselfish

description: The three-dimensional (3D) structure of habitats influences how prey
 detect and respond to predators, but the specific roles of different
 aspects of structural complexity remain poorly understood, particularly in
 coral reef ecosystems. We used 3D models of three Caribbean reef sites to
 quantify three structural metrics at site-level: field of view (the extent
 of observable area), refuge density (density of holes), and rugosity (reef
 surface roughness). We then observed the anti-predator behaviour of
 damselfish, parrotfish, and wrasses at each site. Refuge density was
 similar across sites, likely reflecting long-term regional loss of
 fine-scale complexity in the Caribbean. Territorial damselfish showed
 species-specific responses to habitat structure, especially in relation to
 field of view. Stegastes adustus, for example, exhibited shorter flight
 initiation distances (FIDs) at the site with the highest field of view,
 consistent with expectations from optimal escape theory. In contrast,
 wrasse and parrotfish species showed little variation in behaviour across
 sites, though larger individuals tended to have longer FIDs and flight
 distances. While rugosity is widely used as a proxy for reef complexity,
 our results suggest that field of view may be more strongly associated
 with differences in anti-predator behaviour, particularly in damselfish.
 These findings highlight the need to assess multiple dimensions of habitat
 structure, as even closely related species may exhibit distinct
 behavioural adaptations to their 3D environment.
description: # GENERAL INFORMATION **1. Paper Citation** Boon, J. S., Stratford, J. E.,
 Lynch, J., Yesson, C., Keith, S. A., Exton, D. A., & Field, R. (2025).
 Site-level field of view is associated with altered anti-predator
 responses in farming damselfish. *Behavioral Ecology*   **2. Abstract**
 \[see above]   **3. Originators** James S Boon   **4. Contact
 information** James S Boon Location: School of Geography, University Park,
 University of Nottingham, UK Email:
 [boony9@hotmail.co.uk](mailto:boony9@hotmail.co.uk)   **5. Date of data
 collection** June to August 2022 and 2023   **6. Geographic location of
 data collection** Utila, Bay Islands, Honduras   **7. Funding sources**
 Natural Environment Research Council   ## **ACCESS INFORMATION** 1\.
 Licenses/restrictions placed on the data None   2\. Data derived from
 other sources No   ### **DATA FILES AND VARIABLES** **1.
 anti_predator_data_beh_ecol.csv** This .csv file contains the raw
 anti-predator response data collected in the field. In the file are the
 following columns: •         Site: The dive site where anti-predator
 response data was collected. •         Date: The date the data was
 collected (day/month/year). •         Dive_start_time: The time we entered
 the water and began both the dive for data collection. •         Group:
 Broad taxonomic category of the focal fish used in the anti-predator
 response experiment (e.g., damselfish, parrotfish, wrasse). •        
 Species: The specific species of the focal individual •         Length:
 Estimated total length of the individual (cm). •         Group_size:
 Estimated number of conspecifics present (NA represent "Not
 applicable" due the individual not being in a group). •         SD:
 Starting distance, which is the distance between the model predator and
 the focal individual when the approach began (cm). •         FID: Flight
 initiation distance, which is the distance between the model predator and
 the focal individual when escape behaviour was initiated (cm). •        
 Escape_response: General category of escape behaviour after the model
 predator was presented (e.g., flee, evade, take shelter/refuge). •        
 Distance_refuge: For individuals that took refuge, the distance from the
 initial flight point to the refuge (cm; NA denotes "Not
 applicable" due to the individual not fleeing in to a refuge).
 •         Distance_fled: For individuals that fled into open water, the
 distance travelled before slowing down (cm; NA denotes "Not
 applicable" due to the individual not fleeing in to open water)
 •         Refuge_type: Type of refuge used if the focal individual sought
 one (e.g., live coral, rock, dead coral; NA denotes "Not
 applicable" due to the individual not fleeing in to a refuge).
 •         Investigator: The person who took the measurements for that
 specific experiment.     **2. refuge_data_antipred.csv** This .csv file
 contains the raw data from the refuge analysis. In the file are the
 following columns:] •         Site: Name of the dive site around Utila.
 •         Quadrat_number: The quadrat (replicate) used in the refuge
 analysis. •         Hole_size: The predefined refuge size being counted.
 •         Hole_count: The number of refuges of that size.   **3.
 raw_viewshed_data.csv** This .csv file contains the raw data from the
 field of view/viewshed analysis. In the paper, we report the mean values,
 but here you will find the raw measurements for each field of
 view/viewshed taken on every transect at each site. In the file are the
 following columns: •         Site: Name of the dive site around Utila.
 •         Transect: Name of the individual 3D transect where the cross
 section and measurements were taken. •         Angle: The angle to the
 highest topographical point from a set point. •         minus_90: The
 angle value minus 90°, showing how much of the view is unobstructed.
 •         Proportion_visible: The proportion of the 90° field that is
 visible. This is the value used to determine field of view/viewshed.  
 **4. viewshed_dates.csv** This .csv file contains the mean data from the
 field of view/viewshed analysis. In the file are the following columns:
 •         Site: Name of the dive site around Utila. •         Transect:
 Name of the transect where the field of view/viewshed measurements were
 taken. •         Viewshed_mean: Mean field of view/viewshed value for each
 transect (calculated from the Proportion visible column in the
 raw_viewshed_data.csv file). •         n: Number of individual data points
 used to calculate the mean (verified against the Proportion visible values
 in raw_viewshed_data.csv).   **5. Rugosity_sites.csv** This .csv file
 contains the raw data from the rugosity analysis. In the file are the
 following columns: •         UniqueID: Name of the transect where the
 rugosity measurement was taken. •         Site: Name of the dive site
 around Utila. •         Rugosity: Rugosity value for each transect.    
 #### CODE SCRIPTS **1. Behav_ecol_2025_antipred_code.R** The R script used
 for the paper’s statistical analysis includes comparisons of structural
 metrics between sites and analyses of anti-predator behaviours for each
 taxon across sites.   ##### SOFTWARE VERSIONS R v. 4.2.3   **Loaded
 packages and version:** •         tidyverse: 2.0.0 •         ggpubr: 0.6.0
 •         ggdist: 3.3.2 •         ggpp: 0.5.7 •         grid:base
 •         brms: 2.21.0 •         tidybayes: 3.0.6 •         bayesplot:
 1.11.1 •         brmstools: 0.5.3 •         emmeans: 1.10.2 •        
 ggeffects: 1.6.0 •         DHARMa: 0.4.6 •         car: 3.1-2 •        
 rstatix: 0.7.2 •         report: 0.5.8