Well, last summer a LARGE bumble appeared outside my dining window. The "yard" there is ~5 feet across, bounded on the other side by a wooden fence. It hovered, like a shark in moving water, it seemed, where the breeze came between the house and fence. As ANY bug, bird, etc., flew nearby, it zoomed off AFTER said invader, and then immediately flew back to its position.

Since it flew away whenever I had to go near, I decided to watch and enjoy.

About a month ago, it (or one) appeared in the same spot, same behavior. Then, a week later, a second, which seemed to be an "invader" as the first did NOT like the 2nd and zoomed after it over and over. I figured it got tired, and hence allowed said intruder to hang out sometimes nearby (although I also noticed some perching on the wooden fence by the 2nd).

Now, suddenly, we have 4. Did I say they are LARGE?

What are they? I'll post up some photos, not very clear because I took them from inside (they zoom off when I go out).

Should I be worried? (I read the Canadian LARGE bee post).

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