Castor sure works well in the North Country, whenever there is open water, a magnet, but a deterrent if they fire a trap at a castor set and get wised up. Castor then becomes a repellant. Usually get one change with castor. The deceased beaver above reminds me of Butch Cassidy when they blew up the train, "think you used enough dynamite there Butch." Think you used a big enough rifle? maybe a 300 Win Mag.?
Did a fair amount of night shooting in the past with very good results, arriving just before dark, with just a .22 with Bull Barrel, very accurate. Great for smart beaver. I used an 8 foot step ladder at times, but a 10 or 12 would be better yet. Still there are at least two kinds of beaver, splashers with no brains that swim in circles until they get shot, and smart ones that just roll under and disappear, never to return, one chance. You should be positioned before the smart ones come out, stay down wind on a calm night and don't make a sound. If one small stick cracks they will often be gone for the night. At least they have no vision.
Don't feel so much like going out at night after trapping all day, like I did when I was younger. But, was hard pressed for time the other day, only a few hours before going to the Nationals and needed to finish the job before leaving for two weeks. Went to the pond with a high bank at 9 p.m. and shot one in two minutes. Got there and noticed him swimming down the channel right at me. Have always used a .22 but this time a .22 mag. After explaining to the Sheriff what I was doing, the second one swam back up stream. Water was high, so I started pulling mud and sticks from inside the 7 foot box culvert, with a 5 foot dam. It had been about 45 minutes since arriving. From inside the culvert I could see some ripples in pitch black with a small headlight. I crawled up on the dam and started pulling more mud and saw the beaver out 25 feet or so, getting closer, not liking the sound of running water. He went down and came up about 12 feet away, then down again and popped up at little more than arms length. Cool, the mist and fog and my own breath made it difficult to see, but I was able to dispatch him with one good shot with the potato hook. In 90 minutes, the job was done. The potato hook as come in handy other times for beaver and once for a rabid fox. Good idea to have a firearm or potato hook close at hand as beaver can get aggressive when they smell castor.