Stream reach electroshocking for invertebrate manipulation (Heptageniidae)

Knowledge graph centered on Stream reach electroshocking for invertebrate manipulation (Heptageniidae) with 32 nodes and 111 connections. Top connected: Rocky Mountain Biological Laboratory, Crested Butte, Diptera, Mayflies, Neothremma.

Method synopsis

Large-scale manipulation technique using backpack electroshocker to reduce invertebrate densities across a 50-meter stream reach through induced drift, with daily treatments maintained for two weeks. This enables testing of grazer effects on primary producers at natural spatial scales.

Synthesized from method descriptions across 1 paper using this protocol.

Procedure as described in the canonical source

Steps below were extracted from the paper that introduces this protocol — Reach-scale Manipulations show invertebrate grazers depress algal resources in streams (2002), Limnology and Oceanography. Implementations in other papers (listed below) may differ.

1. Deploy electroshocking blocknet and equipment setup
   A 280-μm mesh blocknet was placed at the upstream end of the 50-m reach to prevent drift into the treatment area while electroshocking. Generator-powered backpack electroshocker was equipped with a circular 10-cm anode. Electroshocking was performed from the stream bank to minimize physical disturbance of the stream bottom, without disturbing substrate with the anode.
   Quantities: 50-meter reach length, 280-μm mesh blocknet, 10-cm circular anode diameterDuration: Setup before daily electroshocking treatmentsConditions: Electroshocking performed from stream bank to minimize disturbance
   Equipment: 280-μm mesh blocknet, generator-powered backpack electroshocker, circular 10-cm anode (Model 15-C, Smith-Root)
2. Daily electroshocking treatment
   Invertebrate density was reduced by inducing invertebrate drift using electrical current with specific parameters: 500-700 V DC, 6 ms pulse width, 60-80 pulses per second, applied over a large area (42-55 m²). The anode was passed over the stream bottom with electricity off for a similar amount of time to control for drift effects. Treatment was repeated daily for 14 consecutive days.
   Quantities: Treatment area = 42-55 m², electrical parameters: 500-700 V DC, 6 ms pulse width, 60-80 pulses per secondDuration: Daily treatments for 14 consecutive days, each treatment session not specifiedConditions: Daily electroshocking from 31 August through 15 September 1999
   Equipment: backpack electroshocker with specified electrical parameters

Typical Equipment

• generator-powered backpack electroshocker
• circular 10-cm anode (Model 15-C, Smith-Root)
• 280-μm mesh blocknet

Output Measurements

• invertebrate density reduction
• community composition changes

Papers Using This Protocol (1)

Species Studied With This Protocol

Places Where Used