Credit: Eudes Emilio Sanchez (Colombia)
The top structures seen over the fish ponds are lines of thread, which are used as a network to prevent fish poaching by birds. These lines of thread are made of weather-resistant materials, and must be placed at a height of 1.8 meters above pond dikes to act against birds and in the same time to allow pond workers to perform their duties. The lines are normally tied to a thick steel wire, this is located in parallel at each end of the pond, and the ropes are performed every 8 feet away from the other a line. The use of such non-lethal, environmentally safe methods of bird exclusion methods has increased in compliance with the protective wildlife legislations.