Survey
The initial survey showed some disturbance to the sea bed caused by the drilling of the 36” section and this will be monitored with additional surveys on the subsequent SERPENT visits. Of most interest was the type of benthic environments in the area. There were very rocky areas and patches of finer sediment. These different habitats should provide interesting contrasts for studying the effects of the drilling on organisms adapted to hard and soft substrata. Examples of the different environments can be seen below:
Ecological highlights
Perhaps the most important outcome from this initial visit to Cashel is the documentation of the different species in the area. This was done by filming examples of the different species using the video camera system on the ROV. This enables us to know more precisely which animals have been seen in the video surveys and gives us an understanding of the ecology of the area in order to plan experimental work for subsequent visits. Video and photographs of the animals seen at Cashel can be viewed in the SERPENT database. Examples of the organisms seen at Cashel are shown below:
Echinoderms, particularly asteroids, were common at Cashel. This one, probably Luidia sp. was one of the larger examples.
Other Asteroids at Cashel included the spectacular sunstar (left) and Porania pulvillus (right) seen here with its body wrapped around a hydroid it is feeding on.
This octopus, hiding behind a rock, was the only example seen at Cashel.
Hermit crabs were abundant on the sea bed at Cashel. They were regularly seen scuttling across the sea floor during the video surveys. Here many of them were observed in one area.
Dogfish were common at Cashel. These small sharks were inquisitive, often coming up to investigate the ROV, perhaps to find morsels of food stirred up from the sea bed by the thrusters on the vehicle.
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