Okay, she lost a swarm...everyone does, even experienced beekeepers. Tough cookies. If my swarm entered a hollow tree, do I have the right to ask the homeowner to cut down the tree? Losing swarms made me a better beekeeper.
Now she wants it back because she's "a beginner?" She's playing the victim card. So does she want to re-combine the swarm with the original hive or make a second colony? She should still have a viable colony with her original hive, and a brand new queen...if she gets on the stick and cuts out all but one swarm cell. Does she know how to do this? Does she know what to do with a returning swarm?
Plus, she probably wasn't going to make any honey the first year, anyway. She can still build up her colony for next year so she hasn't really lost anything. And 1.5 km is almost one mile away...I doubt your caught bees came from her swarm. I can't off-hand quote Seeley's work, but it's a stretch to think those were her bees (and you can't prove it, anyway).
However, if this were me, I'd take the upper path, be a professional, help her know what her options are, and return the swarm...maybe even install it in her old hive for her, which means you have to deal with queen cells or the old queen. There's more goodwill to be gained in giving back the swarm.
There will be other swarms to catch...probably from her hives. It's called Karma and being greedy with this one swarm will likely bite you in the butt sooner rather than later. Returning this swarm may result in a couple of different swarms in the future. Just keep your mouth shut next time.
Grant
Jackson, MO
I'm hot on swarm trapping
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