My Dad once told me a story about crows. Dad is an electrician by trade and he was working for a company that installed shearing equipment in Western Queensland in Australia.
Sometimes the work slackened off for one reason or another so the installers would amuse themselves in various ways. No Aussie sheep farmer would ever curse you for killing crows so Dad and his mates used to have a crack at them when they got a chance.
As others have posted, crows can recognize a threat so after you've shot one or two, they figure out what's going on. Dad and two mates were shooting the crows from an out-building that was close to their quarters. They walked up the first time and shot a crow through the window in the shed. No crows came around after that. So they trooped back with the rifle and waited.
Eventually more crows showed up they went up and shot one. No more crows. Given time, the crows came back again but as soon as the three of them started up to the shed with the rifle, the crows flew off. Smart. When the crows came back. They walked up to the shed without the rifle. Crows stuck around. "Hmmm", they thought, "The crows know what a rifle is now"
They thought about it for a while and came up with a plan. One guy walked up to the shed with the rifle and left it there. The crows flew off when they saw the rifle. They waited until the crows came back and then strolled up to the shed with a broom. The decoy fooled the crows and they flew off. Then two of them walked back with the broom. The crows saw this and soon after the two reached the quarters with the broom, the crows laded back in the trees. The one left behind with the rifle popped a crow
They repeated this method over and over. My Dad analyzed the situation this way "Crows might be smart but they can't count!"
Sorry if this was a bit long winded but I always liked that story.
