U. S. Department of Commerce American Samoa Government
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There were six species of coral recorded in Fagatele Bay in 2007/8 that had not been recorded in the bay previously. The nomenclature used in previous surveys was continued in this survey. Species recorded for the first time in Fagatele Bay in 2007/8 are: Family Acroporidae Acropora formosa Montipora hispida Family Fungiidae Fungia concinna Fungia klunzingeri At the family level, Fagatele Bay coral communities were dominated by Acroporiids (905 colonies). Oculinids (536 colonies), Poritiids (569 colonies), Faviids (112 colonies), and Pocilloporiids (158 colonies) were also an important component of the coral communities. This is the same pattern as in the 2004 survey. The density of corals (number of colonies per square meter) varied across transects and depths (Table 3). We recorded an average of 14.5 colonies/m2 across all transects and depths compared to 15.3 colonies/m2 recorded in 2004 (Green et al, 2005). The highest density (40.8 colonies/m2) was at 6 m depth on transect 3. The lowest density was (4.9 colonies/m2) was at 12 m depth on transect 5. This is the same pattern as in the 2004 survey. Coral cover recorded in Fagatele Bay in 2007/8 ranged from 27.1% at 12 m on Transect 3 to 108.0 at 3 m deep on Transect 4 (Table 4). Note that due to the nature of the calculation of coral cover based on the largest diameter, areas are likely to be somewhat overestimated and total cover can exceed 100%. A full summary of all data from the 2007/8 survey of Fagatele Bay, including the number of colonies in each size class and estimates of percent cover for each species, is presented in Appendix 3. Table 2. Total number of colonies of each coral family recorded in surveys in Fagatele Bay and Pago Pago Harbor in 2007/8.
In general, Fagatele Bay coral communities are dominated by small colonies (<20 cm diameter). Almost one third (32.3%) of corals in Fagatele Bay were in size class 2 (5-10 cm), and less than 1% were over 80 cm diameter (see Table 5). In general, recruitment (gauged as number of colonies <5 cm diameter) was highest in shallow water at all sites. However, a confounding factor is that the most common species, Galaxea fascicularis, only grows to a maximum of about 20 cm in diameter here, and it is most common in shallow water. Alveopora sp. and Porites sp. 2 also are small, rarely growing larger than about 10 cm. Porites rus also frequently produces clusters of many small colonies. Trends in Fagatele Bay coral populations 2004-2007/8 Coral communities on the reef slope showed a decrease in coral cover (Table 4) from 2004 to 2007/8, consistent with the community having largely recovered from previous disturbances and having reached equilibrium. A graph of the change in coral cover since 1985 shows a period of rapid increase in coral cover, and a smaller decrease in the present survey (Figure 3). 
Figure 3. Coral cover change from 1985 to 2007/8 in Fagatele Bay Coral density varied considerably among years and sites. Of the 14 transects surveyed, seven showed increases in density and seven showed decreases. Most of these changes were not dramatic, but Transect 3 at 6 m depth increased from 25.8 to 40.8 colonies/m2 and Transect 5 at 6 m increased from 7.7 to 21.6 colonies/m2. Most of the changes likely represent variation in the exact sampling site between the two years. Coral colony size distributions for 1995, 2004 and 2007/8 are compared in Figure 4. The proportion of corals in the smallest size category (<5 cm) decreased over this period, and the proportion of corals in categories 3-5 increased. This supports the view that corals were growing in size during this period. 
Figure 4. Coral colony size distributions over time from 1995 to 2007/8. Table 3. Density of hermatypic corals (number of colonies per m2) in Fagatele Bay National Marine Sanctuary from surveys conducted in 1984-2008. Data from 1984-2004 are from Green et al (2005).
Table 4. Percent cover of substrata by hermatypic corals in Fagatele Bay National Marine Sanctuary from surveys conducted in 1985-2007/8. Data from 1995, 1998 and 1995 are from Birkeland et al 2003.
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