Seabed Baited Remote Underwater Video (sBRUV)

Overview

The sbruv/ dataset contains all seabed baited remote underwater video (sBRUV) data collected during Pristine Seas expeditions. sBRUVs are stereo camera systems deployed on the seafloor with standardized bait to attract and record fish assemblages in a non-extractive manner.

The sBRUV protocol involves deploying paired cameras on a frame with bait for a standardized soak time (typically 60-90 minutes). This method is particularly effective for detecting mobile predators, sharks, and other fish that may be attracted to bait, providing complementary data to visual survey methods.

Each sBRUV deployment represents a single sampling unit where both cameras record simultaneously, allowing for stereo analysis and accurate fish length measurements. The dataset structure reflects this approach with deployment-level metadata, individual fish observations, and summary abundance metrics.

sbruv/
├── stations      # Individual sBRUV deployments with metadata
├── detections    # Individual fish observations with timing and size data
└── maxn_by_taxa  # Maximum number of individuals by species per deployment

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Tables

Stations (sbruv.stations)

The sbruv.stations table contains one row per sBRUV deployment. Each deployment represents a distinct point in space and time where a stereo camera system was deployed on the seafloor with bait. Since each sBRUV site has exactly one deployment at one specific depth, there is a 1:1 relationship between sites and stations, eliminating the need for a separate sites table.

This table stores all deployment metadata including spatial information, equipment details, environmental conditions, and deployment parameters. It follows the core site schema shared across methods and adds sBRUV-specific fields for camera equipment, bait type, and bottom conditions.

Table 1: Schema for sbruv.stations: sBRUV deployment metadata

Field	Type	Required	Description
ps_station_id	STRING	true	Unique station ID (ps_site_id_depth), e.g., PNG_2024_sbruv_001_25m
ps_site_id	STRING	true	Site identifier (exp_id_method_###), e.g., PNG_2024_sbruv_001
exp_id	STRING	true	Expedition ID (ISO3_YEAR)
region	STRING	true	Broad geographic or administrative unit
subregion	STRING	true	Intermediate feature within the region
locality	STRING	false	Local named feature such as a village, bay, or reef
date	DATE	true	Date of sBRUV deployment (YYYY-MM-DD)
time	TIME	true	Deployment time (HH:MM:SS)
latitude	FLOAT	true	Deployment latitude (decimal degrees, WGS84)
longitude	FLOAT	true	Deployment longitude (decimal degrees, WGS84)
depth_m	FLOAT	true	Deployment depth (meters)
distance_shore_km	FLOAT	false	Distance from nearest shore (km) - calculated
habitat	STRING	true	Dominant habitat type (e.g., fore_reef, channel, bank)
exposure	STRING	true	Wave/wind exposure (windward, leeward, lagoon, etc.)
bottom_type	STRING	false	Substrate description at deployment site (e.g., sand, coral_rubble, rock)
team_lead	STRING	true	Name of the field lead or technician responsible for deployment
rig_id	STRING	true	ID of the camera rig used (e.g., RIG01, SBRUV_A)
left_cam	STRING	true	Model or serial number of the left camera
right_cam	STRING	true	Model or serial number of the right camera
bait_type	STRING	true	Type of bait used (e.g., sardines, skipjack, local_fish)
uwa_opcode	STRING	false	UWA operation code for this deployment (e.g., PNGS24_001)
highlights	STRING	false	Notable events during deployment (e.g., large predator presence)
video_quality	STRING	false	Assessment of video quality (excellent, good, poor, unusable)
notes	STRING	false	Additional comments or QA annotations

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Detections (sbruv.detections)

This table contains individual fish observations recorded during sBRUV deployments. Each row represents a specific fish or group of fish observed at a particular time during the video analysis, including behavioral and size measurement data from stereo analysis.

This detailed temporal data enables behavioral analysis, arrival time studies, and provides the raw data from which MaxN values are calculated. Key station and spatial metadata are denormalized to enable efficient querying.

Table 2: Schema for sbruv.detections: individual fish observations with timing and measurement data

Field	Type	Required	Description
detection_id	STRING	true	Unique detection ID (auto-generated)
ps_station_id	STRING	true	Foreign key to sbruv.stations
ps_site_id	STRING	true	Site identifier - denormalized for performance
exp_id	STRING	true	Expedition ID - denormalized for performance
time_min	FLOAT	true	Time of observation (minutes from deployment start)
frame	INTEGER	false	Video frame number (if available)
filename	STRING	true	Video filename (e.g., PNG_2024_sbruv_001_L.avi, PNG_2024_sbruv_001_R.avi)
region	STRING	true	Region name - from stations
subregion	STRING	true	Subregion name - from stations
habitat	STRING	true	Habitat type - from stations
depth_m	FLOAT	true	Deployment depth - from stations
distance_shore_km	FLOAT	false	Distance from shore - from stations
date	DATE	true	Deployment date - denormalized for temporal queries
accepted_name	STRING	true	Scientific name (Genus species) of observed taxon
accepted_aphia_id	INTEGER	true	WoRMS AphiaID — foreign key to taxonomy.fish
rank	STRING	true	Taxonomic rank (species, genus, or family)
family	STRING	true	Family of the observed taxon
field_code	STRING	false	Original field identification code (if used)
count	INTEGER	true	Number of individuals observed at this time point
life_stage	STRING	false	Life stage (adult, juvenile, unknown)
activity	STRING	false	Behavioral activity (passing, feeding, investigating, resident)
length_mm	FLOAT	false	Estimated total length (mm) from stereo measurement
precision_mm	FLOAT	false	Measurement precision/error (mm)
length_type	STRING	false	Type of length measured (TL, FL, SL)
notes	STRING	false	Observation-specific comments or notes

Detection vs MaxN Data

Detections Table: Contains all individual observations throughout the deployment - Multiple records per species as fish appear, leave, and return - Enables behavioral and temporal analysis - Raw data for calculating MaxN

MaxN Table: Contains summary statistics per species per deployment
- One record per species showing peak abundance - Derived from detections table - Standard metric for BRUV abundance comparisons

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MaxN by Taxa (sbruv.maxn_by_taxa)

This table contains species-level summaries for each sBRUV deployment using the MaxN metric—the maximum number of individuals of each species observed in a single video frame during the deployment. MaxN is the standard metric for BRUV analysis as it provides a conservative abundance estimate that minimizes double-counting of mobile individuals.

Each row represents a unique combination of deployment (ps_station_id) and species, with taxonomic information standardized using accepted_aphia_id from taxonomy.fish. Key deployment and spatial metadata are denormalized to enable efficient querying without joins.

Table 3: Schema for sbruv.maxn_by_taxa: MaxN abundance by species per deployment

Field	Type	Required	Description
ps_station_id	STRING	true	Foreign key to sbruv.stations
ps_site_id	STRING	true	Site identifier - denormalized for performance
exp_id	STRING	true	Expedition ID - denormalized for performance
region	STRING	true	Region name - from stations
subregion	STRING	true	Subregion name - from stations
locality	STRING	false	Locality name - from stations
habitat	STRING	true	Habitat type - from stations
exposure	STRING	true	Exposure type - from stations
date	DATE	true	Date of deployment - denormalized for temporal queries
depth_m	FLOAT	true	Deployment depth (meters) - from stations
distance_shore_km	FLOAT	false	Distance from shore - from stations
bait_type	STRING	true	Bait type used - from stations
uwa_opcode	STRING	false	UWA operation code - from stations
accepted_name	STRING	true	Scientific name (Genus species) of observed taxon
accepted_aphia_id	INTEGER	true	WoRMS AphiaID — foreign key to taxonomy.fish
rank	STRING	true	Taxonomic rank (species, genus, or family)
family	STRING	true	Family of the observed taxon
trophic_group	STRING	false	Trophic group classification from taxonomy.fish
common_name	STRING	false	Common name from taxonomy.fish
maxn	INTEGER	true	Maximum number of individuals observed in a single frame
maxn_time_min	FLOAT	false	Time (minutes from start) when MaxN was recorded
first_arrival_min	FLOAT	false	Time of first appearance in video (minutes from start)
mean_length_cm	FLOAT	false	Mean estimated length from stereo analysis (cm)
min_length_cm	FLOAT	false	Minimum estimated length (cm)
max_length_cm	FLOAT	false	Maximum estimated length (cm)
n_measured	INTEGER	false	Number of individuals successfully measured
notes	STRING	false	Species-specific observations or notes