Birds chasing our Goldfish

Here’s a great blue heron sitting on a bush that looks too frail to support it. It is lurking at the edge of the marsh hoping to have another go at our goldfish. We seem to spend our time recently shooing large birds out of the pond. First the egrets, now this. I hope the pond still has the goldfish shelters that I built into it in the first place: hideyholes under large stones propped up on bricks. I know stones and debris have fallen into the pond. I just hope they haven’t blocked the hiding places, but it is much too cold and wet at the moment for me to get into the pond to find out.