The local rat population is still thriving down at the edge of pond. It’s not as though the place is overrun with them (you do have to look carefully to see them), but they are certainly there.
Generally these rats are very shy and will scurry under cover at the slightest movement. The younger rats are bolder (i.e. they have a less well developed sense of danger), hence this sequence is of a juvenile.
The final shot is simply to prove that the adults are around. It’s much larger than the young rat, and as you can see it has a much squarer head. I’d spotted it several times as it ranged along the bank of the pond, but apart from this one shot it was always to fast for the camera.
Camera note: all shots taken with the Canon 7D and EF 100-400mm f/4.5-5.6L USM IS lens.