Trotlines are used in commercial angling and can be set up across a channel, river, or stream to cover an entire span of water.
There are many ways to set a trotline, with most methods involving weights at the end of snoods to keep them neatly below the water surface.
Webster's dictionary defines a setline as being "a long heavy fishing line to which several hooks are attached in series."
The Virginia Department of Game & Fisheries defines a trotline as "a line without a rod or reel attached that need not be held in the hand or closely attended."
As used for crabbing, a trotline is nothing more than a long line, resting on the bottom and anchored at both ends, to which a series of baits are attached at intervals of two to six feet.
Before constructing the trotline, it is a good idea to measure the span of the body of water being fished in order to give the main line an appropriate length.
It is also typical to avoid setting lines directly over stumps, branches or other obstacles that might cause the fish to get tangled.
It is important to make sure that the area where the line is to be set is free of swimmers, boaters, or other people on or near the water as it is difficult to detect where a trotline is while it is underwater.
Care is needed when checking or setting the line to make sure that no one is accidentally hooked in any part of the process.