§ 226.231 Critical habitat for the Nassau grouper. Critical habitat is designated in the following state and territories as depicted in the maps below and described in paragraphs (a) through (d) of this section. The maps as clarified by the textual descriptions in this section are the definitive sources for determining the critical habitat boundaries. ( a ) *Critical habitat boundaries.* Except as noted in paragraph (c) of this section, critical habitat is defined as: ( 1 ) Navassa Island—All waters surrounding Navassa Island, from the shoreline to the 30 m isobath.
( 2 ) Puerto Rico Unit 1—Isla de Mona and Monito—All waters surrounding the islands of Mona and Monito from the shoreline to the 50 m isobath.
( 3 ) Puerto Rico Unit 2—Desecheo Island—All waters surrounding the island of Desecheo from the shoreline to the 50 m isobath.
( 4 ) Puerto Rico Unit 3—Southwest—All waters from the southwestern shoreline of Puerto Rico, between Playa Tres Tubos just south Mayaguez and Punta Ballena in Guanica, extending offshore to depths of about 10 m and, near La Parguera, to depths of about 15 m.
( 5 ) Puerto Rico Unit 4—Northeast—All waters from the northeastern shoreline of Puerto Rico out to depths of about 10 m between Cabeza Chiquita and Punta Lima.
( 6 ) Puerto Rico Unit 5—Vieques Island—There are two areas that make up this unit. First, all waters from the southwestern shoreline out to the inner reef in depths of about 2 m between Punta Boca Quebrada and Punta Vaca. Second, all waters from the southeastern and northeastern shorelines out to the inner reef in depths of about 2 m between Punta Mulas and Ensenada Honda near Cayo Jalovita.
( 7 ) Puerto Rico Unit 6—Isla de Culebra—There are two areas that make up this unit. First, all waters from the southeastern shoreline of Isla de Culebra out to the reef ledge in depths of about 15 m between Punta del Soldado and Cabeza de Perro, excluding the bays of Puerto del Manglar and Ensenada Honda. Second, all waters from the southern shoreline of Isla Culebrita out to the nearshore reef in depths of about 5 m between the western point of the island and Punta del Este.
( 8 ) United State Virgin Islands Unit 1—St. Thomas—There are two areas that make up this unit. First, all waters off the southeast end of St. Thomas between Stalley Bay and Cabrita Point out to the reef ledge in depths of about 15 m and surrounding Great St. James, Little St. James, and Dog Islands. Second, all waters on the south side of Water Island from the shoreline out to the coral reef in depths of about 5 m between Druif Point and the south end of Sand Bay.
( 9 ) United States Virgin Islands Unit 2—St. John—All waters on the east end of St. John from the shoreline out to the inner coral reef in depths of about 2 m between White Point on the south coast and Leinster Point on the north coast.
( 10 ) United States Virgin Islands Unit 3—St. Croix—There are two areas that make up this unit. First, all waters on the east end of St. Croix from the shoreline to the outer coral reef edge in depths of about 10 m on the north coast and 15 m on the eastern point and south coast between Batiste Point and Pelican Cove Beach, excluding the Christiansted navigation channel. Second, all waters on the north side of Buck Island between the shoreline and the coral reef in depths of about 5 m.
( 11 ) Florida Unit 1—Biscayne Bay/Key Largo—All waters of Biscayne Bay (bounded on the north by the Rickenbacker Causeway), Card Sound (bounded on the south by Card Sound Road), and the Atlantic Ocean out to the coral reef and hardbottom in depths of about 20 m between Stiltsville, south of Cape Florida, and Harry Harris Beach Park near the south end of Key Largo, excluding the Intracoastal Waterway; unit overlaps areas of Miami-Dade and Monroe County.
( 12 ) Florida Unit 2—Marathon—All waters from the southern shoreline of the City of Marathon in Monroe County out to the 15 m isobath between Knights Key and Grassy Key, excluding the Boot Key navigation channel.
( 13 ) Florida Unit 3—Big Pine Key to Geiger Key—All waters south of U.S. Highway 1 out to the 15 m isobath between the eastern point of Big Pine Key and Geiger Key in Monroe County.
( 14 ) Florida Unit 4—Key West—All shoal waters south of Woman Key between 5 and 30 m depth that contain coral reef and hardbottom and seagrass habitat in Monroe County.
( 15 ) Florida Unit 5—New Ground Shoal—All New Ground Shoal waters shown in the map below for this unit in Monroe County.
( 16 ) Florida Unit 6—Halfmoon Shoal—All Halfmoon Shoal Waters shown in the map below for this unit in Monroe County.
( 17 ) Florida Unit 7—Dry Tortugas—There are three areas which make up this unit located in Monroe County. First, all waters surrounding Loggerhead Key to depths of about 2 m. Second, all waters surrounding Garden Key to depths out to about 3.5 m. Third, all waters surrounding Bush Key to depths out to about 5.5 m.
( 18 ) Spawning Site Unit 1—Bajo de Sico—All waters encompassed by the 100 m isobath in the Bajo de Sico area.
( 19 ) Spawning Site Unit 2—Grammanik Bank/Hind Bank—All waters which make up the Hind Bank and the Grammanik Bank, interconnecting waters between these banks, and waters extending out to the 200 fathom line directly south from Grammanik Bank.
( 20 ) Spawning Site Unit 3—Riley's Hump—All waters encompassing Riley's Hump located southwest of the Dry Tortugas out to the 35 m isobath on the north, west, and east side of the hump and out to the 50 m isobath on the south side of the hump.
( b ) *Essential features.* The features essential to the conservation of Nassau grouper are: ( 1 ) *Recruitment and developmental habitat.* Areas from nearshore to offshore necessary for recruitment, development, and growth of Nassau grouper containing a variety of benthic types that provide cover from predators and habitat for prey, consisting of the following: ( i ) *Nearshore shallow subtidal marine nursery areas* with substrate that consists of unconsolidated calcareous medium to very coarse sediments (not fine sand) and shell and coral fragments and may also include cobble, boulders, whole corals and shells, or rubble mounds, to support larval settlement and provide shelter from predators during growth and habitat for prey.
( ii ) *Intermediate hardbottom and seagrass areas* in close proximity to the nearshore shallow subtidal marine nursery areas that protect growing fish from predation as they move from nearshore nursery areas into deeper waters and provide habitat for prey. The areas include seagrass interspersed with areas of rubble, boulders, shell fragments, or other forms of cover; inshore patch and fore reefs that provide crevices and holes; or substrates interspersed with scattered sponges, octocorals, rock and macroalgal patches, or stony corals.
( iii ) *Offshore linear and patch reefs* in close proximity to intermediate hardbottom and seagrass areas that contain multiple benthic types, for example, coral reef, colonized hardbottom, sponge habitat, coral rubble, rocky outcrops, or ledges, to provide shelter from predation during maturation and habitat for prey.
( iv ) *Structures* between the subtidal nearshore area and the intermediate hardbottom and seagrass area and the offshore reef area including overhangs, crevices, depressions, blowout ledges, holes, and other types of formations of varying sizes and complexity to support juveniles and adults as movement corridors that include temporary refuge that reduce predation risk as Nassau grouper move from nearshore to offshore habitats.
( 2 ) *Spawning habitat.* Marine sites used for spawning and adjacent waters that support movement and staging associated with spawning.
( c ) *Areas not included in critical habitat.* Critical habitat does not include: ( 1 ) Managed areas where the substrate is continually disturbed by planned management activities authorized by local, state, or Federal governmental entities at the time of critical habitat designation, and that will continue to be disturbed by such management. Examples include, but are not necessarily limited to, dredged navigation channels, shipping basins, vessel berths, and active anchorages.
( 2 ) Pursuant to ESA section 4(a)(3)(B), all area subject to the Naval Air Station Key West Integrated Natural Resources Management Plan.
( d ) *Maps of Nassau grouper critical habitat.* ( 1 ) Spatial data for these critical habitats and mapping tools are maintained on our website and are available for public use (*www.fisheries.noaa.gov/national/endangered-species-conservation/critical-habitat*).
( 2 ) Overview maps of each final critical habitat unit follow.
[89 FR 155, Jan. 2, 2024]