Is it a rat?

Towards dusk I glanced towards the bird feeder and saw this furry creature eating bird food. I grabbed my camera but had not adjusted for the light so just got this darkish picture. I was adjusting the settings and creeping closer as it scurried back into the bushes. At first glance it looked like a rat as it seemed too big for a mouse. But I recall last year occasionally noticing a small animal coming from the bushes to the feeder. I never got a picture and haven’t been observing closely. If it’s the same animal it is clearly well fed and has grown a lot. Any other explanations gratefully received.