I've never tried trapping them myself, but my husband's uncle's neighbor did out in Golden, Colorado. He had traps out for the jackrabbits. I'm told that jackrabbits are far more difficult to trap than the cottontails. The cottontails will enter a havahart type trap using grated carrots and chopped apples as bait. But the jackrabbits are reluctant to enter small traps. Larger ones need to be used. The fellow used grated cabbage as bait. He said that it took a while before a jackrabbit would become confident enough to enter a trap. He also said that he had to immediately remove the trapped hare from the area otherwise other jackrabbits would learn to avoid the trap. I don't know if that is true or not. I recall he said that the hares and rabbits were both easier to trap during droughts when the grass wasn't so lush and green.
That neighbor only used havahart type live traps. I suppose you could use kill type traps, such as a conibear, but then you'd have to take precautions not to kill/injure dogs, cats, and children.
It's never too late to start! I retired to homestead on the slopes of Mauna Loa, an active volcano. I relate snippets of my endeavor on my blog : www.kaufarmer.blogspot.com
They stay installed full time and the rabbits use the tunnel as a passage way through the fence. When you want to activate the trap they walk through the tunnel and get dropped in the pit beneath. Next morning come along and dispatch them. You can catch multiple rabbits per trap - as many as 20 in one video I saw. They have to be the simplest and lowest intervention type of trap going - once they are setup they will work for years (decades?).
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