It depends on what your goal is...as a record shot it's perfectly acceptable, and for many people that is ok.
At that distance and in those lighting conditions, you already know that you aren't going to be getting any "great" shots of the bird, and really that applies whatever gear you are using, so if you are looking to get a better shot I would say there are four main things that would need to be addressed...the distance to the subject, the angle that the shot is taken from, the cluttered and distracting background and the poor light.