Figure 1.
Map of the Gulf of Mexico depicting the location of the Flower Garden Banks and their nearest neighboring major natural reefs, e.g., the Lobos-Tuxpan reef system, Campeche Bank reefs, Alacran, and the Florida Keys.
Figure 2.
Map of the oil and gas platforms in the northern Gulf of Mexico.
Four cross-shelf transects (I – IV, west to east) were used to examine scleractinian corals on a sub-set of oil/gas production platforms along each transect. Small squaresrepresent platforms. Large dots represent study platforms sampled for corals; see Table 1 for specific names, latitudes, longitudes, and lease area names of platforms. The transects ran generally SE from Matagorda Island, Texas; S from Port Arthur/Lake Sabine, LA; S from Timbalier Island, LA; and SW from Mobile, Alabama. The oval represents a region encompassing the Flower Garden Banks and 13 platforms sampled in an earlier study for coral community development and population genetics [25].
Table 1.
Details of the oil and gas platforms studied in the northern Gulf of Mexico along four cross-continental shelf transects from Matagorda Island, Texas to Mobile, Alabama.
Table 2.
A list of platforms sampled and number of coral colonies sampled per platform in each transect/sector across the northern Gulf of Mexico.
Table 3.
Sequences of the adapters and primers used in the AFLP protocol.
Figure 3.
Genetic affinity in Madracis decactis coral populations on oil and gas platforms across the continental shelf in the northern Gulf of Mexico.
Genetic affinity value (degree of relatedness) determined by the population genetics analytical software STRUCTURE. The reference population was the West Flower Garden Bank; i.e., the population against which all other members of all other populations were compared The peak in the west implies that corals on platforms in that region were most likely derived from the Flower Garden Banks. Population differentiation is evident in the east, on either side of the Mississippi River mouth. The point-depression south of Terrebonne Bay, LA may represent a population drawn from outside of the northern Gulf of Mexico. Note: The orientation of the map has been reversed to east-to-west in order to facilitate viewing of the topography of the three-dimensional pattern generated by the data. This reveals fine-scale structure that would otherwise be hidden using a southerly view. The reader is viewing the region from the north, with east being on the left and west on the right.
Table 4.
Genetic affinities in populations of the coral Madracis decactis.
Figure 4.
Genetic affinity in Tubastraea coccinea coral populations on oil and gas platforms across the continental shelf in the northern Gulf of Mexico.
Genetic affinity value (degree of relatedness) determined by the population genetic analytical software STRUCTURE. The reference population was the West Flower Garden Bank; i.e., the population against which all other members of all other populations were compared. The relative flatness of the curve indicates no major local larval source; i.e., it is unlikely that the FGB are a source of larvae for the region for this species. The steep decline in genetic affinity in the east indicates major population differences between the two sides of the Mississippi River. The point depression south of Terrebonne Bay indicates a population from a very different source than the rest of the western populations. Note: The orientation of the map has been reversed to east-to-west in order to facilitate viewing of the topography of the three-dimensional pattern generated by the data. This reveals fine-scale structure that would otherwise be hidden using a southerly view. The reader is viewing the region from the north, with east being on the left and west on the right.
Table 5.
Genetic affinities in populations of the coral Tubastraea coccinea.
Figure 5.
Map of the Gulf of Mexico, depicting examples of general known currents.
Note the general westerly current along the edge of the continental shelf in the vicinity of the Flower Garden Banks.