The larger stone traps were positioned, using similar principles, occasionally utilizing the natural shoreline of an island to act as one side of the 'V'. Large boulders were built on top of each other, with a core of smaller stones filling the gaps, much in the same way as a dry stone wall is constructed. They reached a height of over 1m.
A wide range of fish would have been trapped, including; Mullet, Plaice, Sea Trout, Mackerel and Herring. The monks of Grey Abbey are credited as being the main builders of these traps, as it would have taken a great degree of man power and organisation to construct, maintain and operate these traps. The amount of fish caught would have been more than enough to feed the monks themselves, and it is thought that much of the fish would have been dried or smoked and then sold. So it really was fishing on an industrial scale.
Today, all that remains of these fish traps are tumbled down lines of stones, only one or two courses high. Many were partially dismantled to use the stones for making Kelp Grids. The best place to see them is in Greyabbey Bay, where it is easy to walk out across the sand at low tide. Once you get your eye in, you realise just how many there are.