Part of your answer is correct, FR: It's a female that has just laid eggs. She's actually nest guarding and has consequently been hanging out a couple of metres away from the nest for the past while.

We've been inundated with rain lately and there is standing water everywhere. The drying puddle in which her footprints were found was right in front of her nest (a puddle always forms there whenever it rains), so water access is not an issue.