My two main pests are pigeons and pheasants. Either one can totally eradicate a fresh planting of brassicas, even before I’ve put the trowel away.
Having tried numerous overly complicated and technical methods of protection, (like the one on the left) I’ve actually found that the most basic of netting systems works just as well and suits my way of growing better.
As I have 1.2 meter wide raised beds, or grow on the same sized strip beds, I use 2 meter square pieces of pond/crop protection netting. Each piece has a 1 meter length of wood stapled to opposite ends, and is draped over supports, to give something like the image on the left.
The nets width gives coverage over the bed with some height for growth. The length could be any size, but my preference for ease of use is 2 meters.
A short length of cane, topped with a tennis ball gives a cost affective, long lasting and snag free method of support.
I have pegged down the sides of the net in the past, but small birds after the bugs and grubs, insisted on getting under and becoming trapped, panicking and unintentionally damaging the crops. I now leave the sides loose to ease their escape, with very little loss of the protections effectiveness.
On plants such as Cabbage and Cauliflowers I leave the net on until Harvest, but on taller plants i.e Brussels Sprouts it’s removed before it restricts their growth.
I don’t think crop protection gets any simpler, unless you know different?