Isla de la Plata is a small island located ~25 km from mainland Ecuador within the Pacific Central-American Coastal Large Marine Ecosystem. It is situated within the Parque Nacional Machalilla (Machalilla National Park) and overlaps with an Ecologically or Biologically Significant Marine Area, the Carnegie Ridge-Equatorial Front. The area is located on the continental shelf, approximately 5 km from the shelf-edge, where the depth (around 200 m) drops sharply. The surrounding waters are characterised by sandy benthos with coral and rocky reef patches to around 30 m depth. The island is fringed with shallow rocky reefs between 5 and 15 m depth with inter-dispersed sandy areas.

The area encompasses the north and west sides of the island, where the bathymetry rapidly descends to >100 m (Harty et al. 2022). It is influenced by the Humboldt Current System, where the merger of coastal and equatorial currents generates upwelling, resulting in high productivity, especially during June–September when the Equatorial Front (the transition zone between water-masses characterised by a large temperature gradient) is at its strongest (Flachier et al. 1997). The increased productivity leads to high zooplankton abundance, which supports a large and diverse food web (Pennington et al., 2006). Inter-annual variability is driven primarily by the El Niño–Southern Oscillation (Burgess et al. 2017).

This Important Shark and Ray Area is delineated from inshore surface waters to a depth of 109 m based on the maximum depth range of the habitat used by the Qualifying Species in the area.