Description: The plankton tow procedure is designed to collect zebra and quagga mussel veligers. The plankton tow net must have a mesh pore size of 64-65 µm. Sample locations are based on high risk areas for mussel introductions, such as inlets and boat access areas (e.g. ramps, docks marinas, etc.). Sample areas are also where water is being pulled out of the lake/reservoir, such as near dam outlets, and areas where the usual wind patterns push water to the shoreline (i.e. downstream and downwind). Mussel veligers are commonly pulled toward these areas. Plankton tows are conducted in both open water and near shore in such a way as to represent the entire water body.
Copyright Text: Colorado Parks and Wildlife Invasive Species Program
Description: The goal of shoreline/stream surveys is to examine as much of the waterline as possible. In a given year, it is generally better to try to survey more areas at the waterbody, rather than survey the same location on every visit. Repeat surveys of these locations will be conducted in future years to obtain long-term data.Qualitative surveys of shorelines (lentic systems, e.g. lakes, reservoirs, ponds) and streams (lotic systems, e.g. rivers, creeks, ditches) are used for several purposes:1. To gather baseline data on species presence or absence in aquatic environments.2. To locate populations of ANS including mollusks, crayfish, and plants.3. To monitor known populations of ANS. (Note: Quantitative protocols may also be implemented to monitor specific ANS populations.)
Copyright Text: Colorado Parks and Wildlife Invasive Species Program