Really like the color of the lichens matching the birds breast, background, sharpness and exposure.
Wish the head was a bit more our way, and I might try a few cropping variations to downplay the mass of the rock a bit. Toning down the luminosity of the rock somewhat would also reduce its impact a bit.
If I were you, I might try and reduce the left slope of the mound in the frame ... especially the last bits with less 'happening' than the rest of the mound ...