I’m sure I will catch a lot of shit (pun intended) for this question, however,
Down in the Gulf Of Mexico, I am on a Drillship warmstacked in Grande Isle. Since going on anchor, we have been overridden by seagulls and pelicans, who sit on the helideck and drop presents down on the bow. Was hoping to get some help coming up with non lethal mitigation techniques, (Scarecrow, fake hawk? etc) as the deck crew is spending a lot of time pressure washing the deck. If the deposits are left on deck for more than a few days becomes tough to remove.
Have used this very successfully on small boats, smaller vessels than yours, on the T-head of our dock, and at our community pool.
String some taut 400# monofilament fishing line over the area. Just a few will do. The birds see it as an impediment to taking off, and will not alight. You can attach some reflective streamers, as at the used car lot, to improve the effect.
Do you have a PA system with a speaker near the problem area?
You could try playing ultrasonic audio all the time that will scare them away. The below video has ultrasonic sound which is said to scare birds, if it doesn’t work try different frequencies, you could have it on loop playing through the PA microphone.
But check you wouldn’t be breaking any local animal welfare rules by doing this.
Adopt a border collie and give him the run of the helipad. Airports use such methods and many others including sonic cannons to keep birds away. Don’t waste your time with plastic owls. It doesn’t take long for the birds to realize they are fake.
Getting a ship’s dog could be a good idea, could keep it in a dog house with a caged area where it can run out and bark at the birds to scare them away.
Trouble with birds is that once they select a spot, they don’t give it up easily.
Had a bird problem on a yacht, and someone suggested snakes. What do seagulls know about snakes?
Saw some inflatable quasi-realistic inflatable snakes at some kind of Nat Geo store and bought a couple. Filled them with water to keep them in place and put them on the yacht. Like magic; birds gone. Even the big blue herons.
I moved them around to keep the game going, but I don’t know if it was really necessary.
Set up a strong sprinkler system that can be turned on and off from the bridge. That’s the best non-lethal bird deterrent system that I’ve seen. If you use salt water you may induce some running rust on deck, so be prepared for some additional metal preservation and maintenance. Lasers are fun but not a realistic solution. Also DPO in eagle costume.
DPO in eagle costume WITH laser pointer device. We have seen the laser pointers work very well at getting the flying rats to take wing when it is pointed at them.