Fighting at the entrance. Short video, what's up?

[Snow Blind]

https://www.youtube.com/watch?v=XaDZTVBHG_c
Have 4 hives of Italians. They were installed on April 9. Today is May 1. A fight broke out in the front of one entrance. Neighbors messing where they don't belong? What might they be doing?

[Barhopper]

Doing what guards bees do I'd say. Doesn't appear to be an attack just a couple strangers without food wanting in.

[KeyLargoBees]

That's whats called "aggressive inspection" its normal.....tend to see it for a week or so and then it fades....and it seems to go in spurts. Might be related to the genetics of the guard bees where the more defensive ones do it...and as they cycle out of the job and are replaced by different guard bees it gets less. At least thats my theory.....I have seen it in how defensive a hive is as you approach it or mow around them...sometimes no issues others they get defensive and you get buzzed and head butted for a week or so and then things go back to normal.....its the bully cop mentality.....Beekeeper Lives Matter!!!!!