Selecting a site
The site operators normally allocate us an area away from the main tip face and provide us with a good load of household waste.
The precise alignment of the net is often determined by the profile of the tip surface, but the wind direction and route of any site traffic need to be taken into account.
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Preparing the net
The net is set on a strip of plastic and attached to four projectiles.
Each projectile is seated in a cannon at the base of which is an explosive cartridge containing a fuse, all of which are connected electrically.
The cannons are seated in old car tyres, to absorb the recoil and weighed down with sacks of mud. Getting the correct inclination and direction is important for a clean fire.
Often a "jiggler" - a cord to which are attached pieces of thin white or coloured plastic - is set along and above the net.
The idea of this it to keep the birds away from the net and out of the danger zone close to the net.
It is important to fire the net over the birds and not hit any with the leading edge as the net deploys at speed.
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Spreading the rubbish
The compactor driver then spreads the rubbish out over the catching area, ideally to match the area covered by the fired net, leaving a safety strip of bare mud along the net.
This activity normally attracts the attention of the gulls and they stream in, often quite close to the wheels of the vehicle.
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Attracting the birds
This feeding frenzy, in turn, attracts more birds, and if things go to plan soon the catching area is filled with gulls.
During this time the gulls will occasionally get "spooked" and all lift off from the tip simultaneously. But if they are hungry enough and there is still food in the waste, they gradually come back.
The smaller Black-headed Gulls are often the first to arrive, but they are soon pushed out by the larger Herring, Lesser Black-backed and Great Black-backed Gulls.
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Waiting for safety
With a long cable connecting the fuses in the cannons to a firing box in a vehicle away from the net but with good visibility of the cannons and the catching area, the wait begins.
Sometimes it is a long wait. We need to be sure that no birds are in the danger zone close to the net, or indeed on the net itself, and there cannot be any birds in the air in a "window" through which the net will travel.
This needs two pairs of eyes, one person watching for safety on the ground and one looking for the "window".
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Firing the net
When there are sufficient birds in the catching area, with none in danger, and a "window" appears, then the net is fired.
The fuses detonate simultaneously and the projectiles are expelled from the cannons, taking the leading edge of the net with them.
Those gulls that do not manage to beat the descending net are trapped under it.
The firing box is disconnected and the team moves in to secure the edges of the net to prevent birds walking out.
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