A total of six shoals were surveyed, with a total of 12 sites and 34 transects. The shoals surveyed were:

• Evans Shoal (2 sites, 6 transects);
• Blackwood Shoal (1 site, 1 long transect);
• Franklin Shoal (1 site 3 transects);
• Flinders Shoal (1 site 3 transects);
• Shoal 9.2 (2 sites, 6 transects) and;
• Tassie Shoal (5 sites, 15 transects).

General Biological Characteristics
The overall impression of the biological assemblages at the shoals was that they were generally similar. There were extensive areas of sand and rubble interspersed with small coral heads and coral bommies. The coral bommie outcrops were generally 1 to 2 m high. There was a range of hard corals with Porites and Acropora being the predominant large forms. Most of the visible macroinvertebrates, fish, seasnakes and many of the seaweeds (algae) were associated with the coral outcrops. The seaweeds Halimeda and Caulerpa were also relatively abundant on coral rubble.

Results of Survey
The results of the transect surveys for each shoal were averaged and are summarised in the attached bar charts. The shoals in the first chart have been sorted from highest coral cover at Blackwood Shoal to lowest coral cover at Evans Shoal.

Comparison of the Six Shoals
Although data for Blackwood Shoal was derived using a remote camera rather than direct measurement by diver at the other shoals, the hard coral cover at Blackwood of almost 35 percent was substantially higher than the 20 percent at Franklin and less than 10 percent at Evans. All other animal groups (soft corals, sponges other invertebrates) and turfs were more abundant at Blackwood than the other shoals. Algal cover was low at Blackwood, but appeared to be dominated by Halimeda like the other shoals. Hence there is a strong indication that the marine biological assemblages on Blackwood Shoal were substantially richer than the other five shoals.

The remaining five shoals were relatively similar. Differences in the number or size of coral outcrops along the transects at each site were the main reason for the variation in the animals groups between the shoals. The data indicate that Franklin and Flinders were the second and third biologically richest of the six shoals examined. Shoal 9.2 and Tassie Shoal were very similar, and Evans Shoal appeared to be the least rich of the six shoals examined.

The amount of algae varied substantially between the shoals. The predominant alga was the calcified green alga Halimeda, with a range of other green and red algae but no obvious brown algae. Halimeda was recorded growing over coral rubble, coral outcrops and, to a lesser extent, on sand at all shoals. Halimeda is an important component of the shoal's ecosystem as it contributes substantial volumes of calcium carbonate to the sediments. The white calcareous segments of dead Halimeda are clearly visible in the sediments at the shoals. Interestingly, the predominant alga at Shoal 9.2 was Caulerpa racemosa, although the abundance of Halimeda remains in the sediments indicated that Halimeda must be abundant at times at this shoal. Studies by AIMS and BHP indicates that the amount of Halimeda present at the Big Banks Shoals is highly variable in time. The AIMS/BHP conclusion was that cyclonic storms can virtually clear the shoals of Halimeda.

Comparison of Five Sites at Tassie Shoal
The marine biological community components at the five sites surveyed at Tassie Shoal were the same as those at the other shoals. There was a small degree of variation between the sites at Tassie Shoal, with most variation due to the amount of hard coral. This variation indicates slightly higher number of coral outcrops along some transects or at some sites. The amount of algae was quite consistent between the five sites at Tassie Shoal.

Conclusion
The data processing and analysis so far support the following general observations of the shoals:

• The sites at the shoals in the vicinity of Tassie Shoal all have generally similar marine biological communities. There are large areas of sand and coral rubble interspersed with coral outcrops and seaweeds.
• Blackwood Shoal appears to have the richest marine biological assemblages of the six shoals due to the high abundance of hard corals and coral outcrops, which provide habitat for a wide range of other marine biota.
• The remaining five shoals are relatively similar to each other, although small differences in the data indicate that Tassie Shoal and Shoal 9.2 are intermediate between the richer shoals of Flinders and Franklin and the less diverse Evans Shoal.
• Compared with the shoals of the Big Banks Study, the six shoals surveyed around Tassie Shoal have less coral cover than the Big Banks "coral" category and much less Halimeda than the "Halimeda" category.
• The marine biological assemblages at the five sites on Tassie Shoal are relatively similar. Together with drop camera observations at other sites on Tassie Shoal, the data indicate that the habitats over the northern top half of Tassie shoal are homogeneous with small, sporadic differences in the density of coral outcrops.
• The marine biological habitats at the proposed location of Methanol Australia's plant on the eastern side of Tassie Shoal appear to be typical of those represented elsewhere on Tassie Shoal and at other shoals in the region.