Safe-Green Laser To Scare/Chase Geese Off Property?

[GSS]

Husker, I would just go with a 520nm green around 100mw+ without a expander if your in a cold climate.
If your talking a distance of 1/2 a football field away the spot should be wide enough not to hurt them but enough to scare them.
Without putting to much money and wanting to test the laser way of bird control, get a 303 style 532nm DPSS for around $12 that comes with a cheap charger and cheap battery. This will give you a idea, and these 303 do around 60mW's to 80mW's..
If you think its a good way to control them then invest in a better one.
Sanwu is also a good company.

 

[Alaskan]

I used a small 100 mw 532 nm laser and pointed at a tree full of birds in Afghanistan once and I was surprised at how fast they scattered. I'm guessing a low powered 20-50 mw 520 nm laser with a 10X beam expander might do the job a couple hundred yards or more away. Not so dangerous at lower power output that far out when expanded either, but you really need to do the math to know for sure. Only thing is, if it is just a dot, the birds might not even see it, too small a spot, try a line laser lens to sweep the line across them at higher power, might be OK because the power is so dispersed when in a line.