One of the fascinating things about the bird strike business is the proliferation of all kinds of tools and techniques that "reduce bird-strikes, guaranteed". Unfortunatley, the vast majority of these claims have zero basis in any scientific study and are hearsay and anecdotal information only. When attending conferences on bird strikes I am amazed at the vendors displays and the wild claims that some of them make. It reminds me of the "snake oil" salesmen from the early part of the 20th century.
This is not say that there aren't good products out there and good techniques, just that careful evaluation of the science (or lack therof) behind the product is important. This must also be coupled with the realization that no single product or technique will solve your bird problems.
Now on to the stringing of cables to discourage birds... Yes, this is an effective technique. You don't need to use steel cables, monofilament line layed out in a grid that is just smaller than the problem bird species landing circling pattern diameter will do the trick. The lines can also be supplemented with mylar strips tied to it. The difficulty can be if you have a large surface area to cover then the construction of the grid can be problematic and may be too easily damaged in high winds.
I am not so sure about the real scientific evidence concerning the effectiveness of the painted pictures of gulls. My research and experience indicates that gulls a wiley and when they figure out that nothing happens when they drop clams near the painted birds they will ignore them. It will work for a short time, but not for any extended period of time. The classic example of this is using propane scare cannons in the same location all the time. the birds habituate to them and ignore them. I personally watched a propane cannon at a major airport where the gull would sit on the cannon and ride the barrel as it swept back an forth. The when it heard the propane valve open it would fly away, wait for the bang and return.
Old Smokey, thanks for information on your experience. As for your comments concerning the early ground radars there may be some element of truth in this, but I can't prove it. Some further things to consider is that bird behaviour when confronted by an aircraft may have created this legend. If a bird is approaching an aircraft with the radar on and then subsequently avoids the aircraft by diving or climbing, then this may be incorrectly interpreted as the bird sensing the radar. The more likely cause is a classic escape maneuver and unless control test were conducted without radar there is no validity to the observation. This is the classic example of establishing a cause and effect relationship where none exists that then becomes "fact".
Richard