[2] The leading edge of the Baixa do Norte reef includes a series of large rocky outcrops, of less than 5 metres (16 ft) in size.

[2] The Baixa is characterized by peaks at the 25 metres (82 ft) depth, with large blocks of rock and a fishery of considerable dimension.

[2] The southern or Baixa do Sul is a meridianal reef situated 2 nautical miles (3.7 km) southeast of the port of Horta.

Due to the importance of these location, various studies by investigators at the regional Department of Oceanography and Fishing (DOP) and University of the Azores (UAç) have delineated these areas by the temporal differences between spring and summer seasons (based on 1997 research), noting a differentiation in marine life during the period, owing to a reduction of anthropological pressures.

[2] The area was designated a ZEC, Zonas Especiais de Conservação (Special Conservation Zone) owing to the important habitats for common terns (Sterna hirundo), loggerhead sea turtle (Caretta caretta) and common bottlenose dolphin (Tursiops truncatus), as well as the Vidália (Azorina vidalii) and Spergularia azorica.