Yellow Jackets.

[Keith Petrosky]

Do yellow jackets attack Monarchs, because by me, yellow jackets are everwhere, and in great numbers.

[Megathymus ursus]

Larvae, yes. Here in SoCal where I am, there is some sort of recently-introduced red hornet that preys heavily on gulf fritillary larvae.

[Caterfly]

I was thinking the lack of monarch sitings was due to the freeze the fall before while they were migrating. I probably only saw 6 monarchs last summer and strangely enough, most of them were flying in roadways where they could get hit by cars. I hope the numbers come up this summer, I am looking forward to seeing their beautiful site once more!