This sometimes happens; you photograph a bird, you are motionless for a long time and then suddenly, out of nowhere, another bird appears nearby and starts to watch you.
That autumn morning on the Great Salt Lake shore, I was photographing American Pipits. At some point I looked over my shoulder and saw a White-crowned Sparrow perching on the bush and watching me. He was so close that for a few seconds I was afraid to aim at him my lens, what if he would flutter and fly away.
The Sparrow didn't have any intention to fly away, perhaps curiosity was much stronger than caution.
Generally, life is good!