Greylag goose

We spotted these large geese across the other side of the river and they appeared just to be feeding so I went to the rivers edge to get a better shot and the next thing I knew they were coming up at the side of me as fast as they could with their necks held high trying to chase me off so I was trying to take pictures of them chasing me whilst walking backwards to get out of their way as they can can be quite vicious geese if they catch you. I'm not sure if they had young/eggs that they were protecting or they just didnt like me being on their patch of river.