New England Wadeable Streams (NEWS)

Electro-Fishing

General Description

The electro-fishing equipment described below is utilized in assessing the overall biological integrity and associated water quality of stream ecosystems. By collecting information regarding species and numbers of fish in streams, the information can help determine whether streams are maintaining healthy habitats and can support other aquatic life. Electro-fishing involves field collection and identification of fish species and enumeration and analysis of biological characteristics.

Equipment

The following is a list of equipment needed to perform electro-fishing:

• Battery or gas powered portable backpack shocking unit with safety kill switch, anode ring, and rat tail cathode
• Elbow length rubber lineman’s gloves, chest waders, polarized sunglasses for each team member
• Large and small dip nets
• Holding bucket with an opening mesh and an aerator
• Large holding bin to place all the fish in when taking the data
• Data sheets and writing utensils

Significance to Biological Integrity of Stream Ecosystem

Electro-fishing equipment is used for collecting different fish species and recording their relative abundances, and making cursory determinations of their health based on external observations. Collecting and recording fish data reveals what species are surviving and inhabiting a particular stream system and to what extent the aquatic ecosystem is maintaining that population. Depending on the type of stream visited and the field chemistry and habitat measurements taken, biologists have certain expectations of what type of species they should expect to find. When this ends up not being the case, as where warm water pollutant tolerant species are found in what would be considered cold water species habitat, then the biologists look closer into possible causes for the ecological imbalance. When combined with water chemistry, habitat, and stream invertebrate information, a clear picture of the ecological system is brought in to focus from which sound management decisions can be made.