It is very simple to deter seagulls with a Green laser, these are easily available from the web – look for 532 green.  The green laser triggers the seagulls flight/fight response and pavlovian conditioning will train the seagulls to go elsewhere.

The best deterant time is dawn or dusk in January to May before they have nested and if they are around from August to December – an area can easily be cleared and the seagulls will go elsewhere.

Some folk may not understand what the DFL’S green light is and to avoid ending up in the local’s Wicker Man or a similar Peter Grime’s fate ensure you use the  laser lawfully and legally :

Don’t point at cars, airplanes, people, animals, into  houses etc.

Don’t use whilst their are chics.

Generally people have an aversion to seagulls because of their scavenging, noise, soiling, attacks, rubbish spilling etc – but remember some folk like them, feed them and make pets of them and so understanding is also called for and care in theIr use.