Water witch : The dabchick.

Water witch : The stormy petrel.

Example:


Taxonomy
vessel, Liverpool, Water Witch, Northern Ireland, Marine, Rivers Agency, the craft, Workboat, tonnes, keel, waterline, oil spill response, marine debris, aquatic, Dollaghan, debris, weed, waterway cleanup.

Defination from the web:
Water Witch for marine cleanup operations, removal of floating debris and garbage, oil spill response, aquatic weed control, weed harvesting and dredging. ... The Water Witch features ease of handling and excellent manoeuvrability - with the craft capable of turning 360 degrees ...