A new sampler for collecting invertebrates in submerged vegetation

A new sampler is described that can rapidly enclose a specific volume of water at a given depth, including submerged macrophytes and associated invertebrates. The sampler is a tong-shaped instrument consisting of two metal rods connected by a flexible joint. At the end of each arm is a metal cylinder (diameter 10 cm); one end of the cylinder has a sharpened edge and the other is equipped with a net. Powerful metal springs force the cylinders together at high speed, and macrophytes are enclosed in the nets. The sampler is suitable for studying vertical and horizontal distribution of invertebrates, even fast-moving taxa, within submerged vegetation. The device causes little disturbance of the vegetation, hence it is also suitable for repeated sampling within mesocosms.