Underwater Visual Surveys

Dataset Overview

The uvs/ dataset contains all data collected using Pristine Seas’ SCUBA-based underwater visual survey (UVS) protocols. These methods assess reef fish, benthic cover, mobile invertebrates, and coral recruits at spatially co-located sites using a standardized, depth-stratified design.

Each UVS site typically includes multiple stations across depth strata, with several survey protocols conducted in parallel.

The dataset structure balances:

• Protocol modularity: each sub-method (BLT, LPI, inverts, recruits) has dedicated tables
• Spatial consistency: shared sites and stations tables ensure alignment across protocols

This architecture enables both focused analyses (e.g., fish biomass by depth) and integrated reef assessments across taxa and trophic levels.

uvs/
├── sites                             # Deployment-level metadata for each UVS dive
├── blt_observations                  # Raw fish counts
├── blt_stations                      # Fish transect metadata (BLT)
├── blt_biomass_by_station_taxa       # Biomass summaries by taxa and station
├── lpi_observations                  # Raw point-intercept records
├── lpi_stations                      # Benthic transect metadata
├── lpi_cover_by_station_taxa         # Percent cover by taxa and station
├── inverts_observations              # Raw invertebrate observations
├── inverts_stations                  # Invertebrate transect metadata
├── inverts_density_by_station_taxa   # Invertebrates density by taxa and station
├── recruits_observations             # Raw coral recruit counts
├── recruits_stations                 # Coral recruit transect metadata
├── recruits_density_by_station_taxa  # Coral recruits density by taxa and station

---

Tables

---

Sites (uvs.sites)

This table stores site-level metadata for all UVS dives. Each row represents a unique SCUBA deployment where one or more survey protocols (e.g., fish, benthic, invertebrates) were conducted.

It inherits all core fields fromexpeditions.sites (e.g., site ID, coordinates, date), and adds UVS-specific fields that describe habitat type, exposure, protection status, and others (Table 1).

Table 1: Additional fields in the uvs.sites table, beyond the core site schema.

Field	Type	Required	Description
site_name	STRING	false	Local site name used in previous surveys or by local partners.
habitat	STRING	true	Dominant habitat type (e.g., fore_reef, `patch_reef``).
exposure	STRING	true	Wave and wind exposure (e.g., windward, leeward, lagoon).
in_mpa	BOOLEAN	false	TRUE if the site is located inside a marine protected area.
mpa_notes	STRING	false	A free-text field to specify the MPA name, protection type (e.g., no-take, seasonal closure), and any other notes

Controlled vocabulary

Habitat

• fore_reef — Seaward-facing outer slope of coral reef
  
• back_reef — Lagoon-facing side behind the reef crest
  
• reef_flat — Horizontal shallow zone near the crest
  
• patch_reef — Isolated reef outcrop within lagoon or sand plain
  
• pinnacle_reef — Steep-sided, often isolated coral structures
  
• bank — Flat-topped offshore feature with reef or rocky habitat
• rocky_reef — Non-coral reef formed from rock, with reef biota
  
• reef_pavement — Flat, low-relief hard-bottom reef surface
  
• channel_pass — Channel through reef system with strong flow
  
• wall — Vertical or steep reef drop-off
  
• kelp_forest — Dense canopy-forming macroalgae habitat
  
• seagrass — Dominant seagrass bed habitat

Exposure

• windward — Exposed to prevailing swell or wind; typically high wave energy and surge
  
• leeward — Sheltered side of reef or island protected from prevailing swell
  
• lagoon — Located inside a reef or atoll, generally protected from direct wave action
  
• channel — Within a reef pass or surge channel; often features strong tidal currents
  
• sheltered — Protected from wave energy by a bay or other geomorphic feature
  
• exposed — Generally high energy due to wave or swell exposure; used where windward/leeward doesn’t apply
  
• unknown — Exposure not determined or insufficient data to classify