MANOSS - a manually operated suction sampler for hard bottom benthos

1 - The design and construction of MANOSS, a manually operated suction sampler, is described. The sampler is designed for sampling aquatic epibionts on hard substrates and is manually operated by SCUBA divers.2 - Building upon the basic design of a slurp gun, it allows for sequential pump actions to effectively scoop a certain sampling area and incorporates easily interchangeable sample collection pouches. Its simple construction, independent from air supply or motorised pumps, makes it compact, lightweight and easy to handle. A relatively large diameter of the intake nozzle (4.5 cm) permits the collection of large fragments of algae or even small pebbles without blocking the valves.3 - Preliminary tests comparing the new sampler to those hitherto in use indicate efficiency of sampling and satisfactory levels of effort during underwater manipulation. The sampler is inexpensive and easy to rebuild following the detailed description and illustrations provided in the manuscript.