Scientific techniques - Visual surveys
Video surveys have become the second key tool in deep-sea research. After a successful mapping program, video cameras and lights will be lowered to investigate key features or targets identified from the mapping programme.
Cameras come in all shapes and sizes, from those lowered from ships on cables to ones mounted on submersibles and ROVs. They all perform the same function, and that is to beam images back to the waiting observers on the surface or in the submersible.
As the sea is a constantly moving medium, it is difficult for a ship to remain in a single place, so many visual surveys are conducted in the form of transects. The ship is controlled along a specific path and using complex mapping software this track can be overlaid with previous mapping efforts to produce an accurate representation of the area. These data can then be used to focus our attention even further, allowing researchers to select specific areas for sampling and to reduce collateral damage when samples are taken.