I am glad you found him very intertaining and I do know him and his owers very well. He gave me a chase before.
He can be very cross at this time of the year.
The owners are starting to think that there is another one about.
In December of 09 he got stuck in the lake when it froze over.
I just had a look at the properties of your photos and I see you took them about 2 in the day so it would be about his feeding time so that could be why he seems cross