Parrots and chickens flap their wings for a couple of seconds when summoned on the ground

Summary:
Parrots and chickens flap their wings for a couple of seconds when summoned on the ground.

Steps to reproduce:

1. Summon a chicken and a parrot on the ground.

Observed results:
The mob flaps its wings for a few seconds after being summoned.

Expected results:
The mob will not flap its wings if summoned on the ground.

Video: