The bridges are very large and bulky, with a thick grey top side and a black underside. They grow out from canyon walls and continue growing, twisting and turning as they go until they meet another wall which they then attach to. The undersides of the bridges are always entirely covered by Blue Barnacles, which appear to be a separate species taking advantage of the bridges.
Some specimens can grow to be extremely large, as shown by one particular bridge found in the Deep Twisty Bridges that measures well-over 250 meters in length.
Data Bank Entry
Coral bridges are formed by rapidly growing coral polyps that exhibit thigmotropism, which causes growth in response to stimuli or when touching a solid object. Coral bridges grow in thick twisted patterns that anchor onto rocks or other coral. The underside is covered in colonies of blue barnacles.
|Source: Scan Coral Bridge|