Cattle sometimes enjoy chewing on survey wire; other times they seem to make an effort to leave it alone. Dragging wire is also a problem. Most of this is avoided by laying wire along fencelines, going around occupied fields. With a final 3D inversion grid having a resolution of 1/4 of an electrode spacing (in all directions), field crew know that they can offset electrodes by 1/4 spacing(s) in any direction to avoid obvious cattle problems, without affecting the quality of the survey results. Maps and GPS are both equipped with 1/4 station interval dots so that an on-site decision can be made to offset to an alternate location to avoid a site that appears to be a likely future problem. The nearby alternate dot is selected on the GPS screen, and the wire is laid to the new location with virtually no loss of time.
While most of the offsets in this image are related to smoothing an optimum electrode spacing through difficult brushy cliffs along the river (e.g. 11-Z), electrode 11-Y is a 1/4 spacing southward-offset chosen to avoid a fenced compound that was found to contain a number of particularly stupid young bulls. The original proposed electrode station locations are shown as grey dots. This image is part of the daily "shoot map" that all crew use to guide layout and shooting progress in the field. It is updated between field shifts to reflect actual wire and station locations in the field. The red oval marks an "open" wire circuit between box 11 and electrode 11-X, seen in the morning system check and marked "red" because it is a repeat issue. The pink "X" oval marks a fresh break, not seen before. A crew person will be assigned to check and fix these wires at the pre-day tech meeting, and will leave as soon as his tasks are known.
Deer farming enclosures in New Zealand are often not particularly big (feedlot operations), and usually involve just one or two electrode sites which might be offset outside the fence. They are, however, usually enclosed by high electric fencing. Arriving prepared with enough wire to go around (rather than through) speeds the survey layout and prevents certain discomfort (no need to climb over the fences),- maintaining survey spacing continuity with some minor offset adjustments.
Orchards like this Kiwi plantation have no animal issues, and can be easily managed by laying wire around perimeters or along rows between machinery access routes.
Scheduling and interaction:
By discussing plans with landowners, survey operators can plan to avoid occasional sensitive times such as the month of lambing, or other annual cyclic events in which livestock are either in unusual circumstances or locations, or under stress.
Farmers can sometimes advise which paddocks may stay vacant. When all else fails, animal-caused wire breaks at key electrode stations may have to be repaired or reinstalled once or twice daily until their
involvement in the survey shooting is done, even going so far as to station a crew person right there to guard a wire for a day or two. The benefits of using farm tracks and roads usually far outweighs delays due to livestock-caused wire damage.