Both shots are great indeed...
I particularly like the crab shot.. DOF, colors and subject are all great, Not that I have anything against seagulls.. But... Its a seagull
which lens is this? Sigma 150-500? 50-500? 170-500?
I had the 170-500mm a few years back and found that it would produce some seriously sharp images provided I held it very steady... right out at 500mm it was brilliantly sharp..
(my best with the 170-500 posted - A Seagull
!!! Hope you dont mind)