Hummingbird and Butterfly Gardening: my BST cats are all dying, what's wrong?, 1 by thea611

thea611 wrote:
Last week I brought in a bunch of tiny first instar BST cats (and some eggs) on my fennel, and all of a sudden, they're all flopping down and writhing and undulating (their little legs are moving but they can't grip or go anywhere). When they die, they're sort of soft and squishy. It looks so agonizing, it's killing me! We don't use any poisons, and I've already had a successful batch of cats that are either in the chyrsalis now, or have already eclosed and moved on. They grew up on the same fennel. I've just removed 4 more cats that are dying, and one of them had strange whiskery things on both ends. I've seen it on a few others too, but not on all of the dying ones. I'm attaching a photo. Can anyone identify what is happening? I'm about ready to give up on this, after three years of raising BST's. I hate how many are lost to the many birds in my gardens, but this is just as bad!!! Worse, because I feel like I'M killing them.....