Mexican Navy Patrol Ship Becomes San Carlos’ Newest Artificial Reef

Mexico’s Navy has deliberately sunk the former ocean patrol vessel ARM Ángel Ortiz Monasterio (PO-26) near San Carlos, Sonora, adding another large ship to the Sistema Arrecifal Artificial Sonorense in the Gulf of California.

The Mexican Secretariat of the Navy said its Second Naval Region conducted the controlled sinking near San Carlos Bay on August 21, 2026. The operation followed the July 10 sinking of the former patrol craft Mariscal (PC-211), continuing a project that combines retired naval ships, aircraft, artillery and an amphibious vehicle in a planned underwater reef system.

Ángel Ortiz Monasterio was built by Empresa Nacional Bazán in San Fernando, Spain, during 1981 and 1982. It entered Mexican naval service on February 24, 1983, originally as the Halcón-class coastguard vessel GH-06, and later served as the ocean patrol ship PO-26. Its duties included maritime patrol, surveillance and security in Mexico’s territorial sea and exclusive economic zone.

Authorities say the hull was technically prepared and that the sinking complied with applicable environmental, maritime-safety and navigation requirements. The project is intended to create hard-substrate habitat for fish and invertebrates while supporting scientific research, conservation and dive tourism.

Sonora officials have separately reported more than 52,000 fish recorded across the developing system, representing 37 species and 30 genera. Those figures are encouraging but need accompanying survey methods, dates, locations and effort before they can be interpreted as evidence of ecological improvement rather than fish attraction.

For divers, the new vessel could become one of the system’s most substantial wreck-style attractions. A San Carlos dive operator describes it as approximately 220 feet long and resting in about 100 feet of water, but those measurements have not been confirmed in the Navy’s public announcement. Official coordinates, orientation, minimum clearance, mooring arrangements, structural condition and permitted access should be established before the wreck is promoted as a ready-to-dive site.

The deployment moves the Sonoran system closer to its expanded target of 16 naval artifacts. An updated regional guide reports 14 installed by August 2026, including several purpose-sunk vessels in shallower recreational ranges and this latest, deeper addition.

The next useful follow-up will be a hydrographic or diver survey documenting how Ángel Ortiz Monasterio settled and whether the site is open to charter and private-boat diving. Biological monitoring will also be important for distinguishing increased production from the concentration of existing fish around new structure.