We made two separate trips for our nature study this week. First we went to the local Pet Shop to look at
rats first hand.
They enjoyed comparing them to mice and were impressed with the difference in size. I have found the Pet Shop a good addition to our nature study on cold winter days.
We also went searching for muskrats and beavers.
We live in an area around the Chesapeake Bay and there are lots of rivers and streams.
We looked around the shores to see if we could see evidence of muskrats, but did not see any. Then we decided to explore an area that someone had told us had beavers. Although we did not actually see any beavers, there was definitely evidence that they had been
there. 
On one
side we saw trees
that had been cut down and stripped and the water was very low, almost swamp-like.
On the other side there was a nice-sized pond.
We could not find a lodge, or a hole in the bank where a beaver (or muskrat, for that matter) could live, but there could have been one there cleverly concealed.