A Missed Opportunity

Grey Heron, Lancaster Canal, originally uploaded by Bay Photographic.

If ever there was a need to prove that a long lens and a sunny day does not make a wildlife photograph, I managed to fulfil it this weekend.
I followed this grey heron up the canal in my boat, steering with one hand and holding my S5 with a Sigma 70-300 in the other until he (she?) decided that enough was enough. Realising that catching dinner was going to be on hold until the bloke in the Orkney Longliner whiffled off (I always like to characterise wildlife as if it is written by P.G Wodehouse) , he stood obligingly on a post and posed for me as I drifted past.
I took a total of 18 shots of the heron as he gazed unblinkingly at me. The camera was set to shutter priority, as I was shooting towards the 300 mm end of the zoom, and told me it was metering 1/142 at f5.6. It was set to shoot Jpeg (I usually shoot in RAW) but was at maximum resolution, so I expected sharp results.
And what's more, I realised that this was an unusual opportunity to photograph a heron, an habitually shy and retiring bird.
So, was I successful?
Was I Swedish Exercise.
Even though this was the pick of the 18, it is soft, badly exposed and lacks definition at anything bigger than the size of this post.
I have given it the full treatment. Photoshop, Adjust, Vivacity, you name it. Nothing can rescue me from my own incompetence.
Apart from the limitations of shooting on a compressed format I assume that I have discovered the limits of both my lens (f8 or bust) and hand holding.
I daresay Gussie Fink-Nottle could have done far better.