We had 5 crows last year & now it’s up to 7 ... a family, it appears. Lots of chatter among themselves and interaction - fun to watch if they weren’t getting into trouble. My dad is an old-school farm boy - he has been telling me to shoot one & hang it up & that will take care of the problem. I’m not inclined to do that & even if I were, crows are a federally regulated migratory species so you can only shoot them during certain hunting seasons - “now” is not in season.
I had already seen the article you linked. None of that really helps me so I’m going to fence the crows out. The fencing is close enough they can’t land between the fence/garden & they cannot perch on the fence. They can’t reach the tomatoes & other veggies through the fence.
In searching the internet, I did see where someone live-trapped crows. They were left in the cage for a couple of hours & after that experience, just seeing the cage kept them away. That is an additional option for me - we have a live trap & two years ago, I accidentally caught a young crow in it (baited with corn & cantaloupe for a groundhog). It was very vocal & quite upset & went screaming off looking for family/buddies when I got it released.
I think the easiest thing for you might be the “dead crow” decoy to warn them away and/or maybe trapping them for some ‘aversion therapy’. You could try a fake snake - supposedly that works for a while & it might be enough that they’d stop coming.
Here’s the dead crow link:
http://birdsoff.com.au/dead-crow-decoy-visual-deterrent/
Some people use ‘Halloween’ decorative crows ... cheaper, but probably wouldn’t last long in weather.
Yes it is illegal to kill crows, so the use of an air rifle or bb gun can be effective, especially when underpowered, or in a residential area .
I consider it a 'persuader' to let the crows know that they are unwelcomed; and crows are remarkably intelligent, social, and have a 'memory'.
The local laws prevent discharge of firearms within the village limits, however an air rifle or bb gun does not issue a loud report, so it will not upset the locals.
My crow blind (AKA bedroom window) was used once this spring and the crows have not returned - thanks to their social skills and memory, which works to your advantage.
They don't like sudden unexpected noises, or sudden movement even if you miss either purposely or by accident.
On the other hand , our regional drought may have encouraged the crows to look elsewhere for greener pastures and gardens for bugs and grubs .