Two Useful Devices for Vertical Plankton and Water Sampling

Abstract

Two devices for taking plankton and water samples are described. One, an inexpensive syringe sampler, will obtain small uncontaminated samples from thin strata in lakes. The other, a self-activating transparent zooplankton trap, combines many of the advantages of both net and trap-type samplers. It is capable of removing the smallest zooplankton and its light weight allows large samples to be taken easily from a small boat. Comparisons with other samplers prove the self-activating trap to be more efficient than other devices which are commonly used.