[EBB Sightings] Heather Farm, large pond

This morning I took a stroll around Heather Farm's large pond and observed, 
in addition to the usual assortment of common birds (blackbirds, Canada 
Geese, Mallards, etc.), the following noteworthy critters:

2  Black-crowned Night Herons
1  Green Heron
1  Red-Shouldered Hawk (dive-bombed a squirrel in a tree!)
2  Song Sparrows, each singing
2  Titmice
1  Nuttall's Woodpecker
1   large pond turtle(?)

And finally, what looked like a beaver or some other large rodent swimming 
across the pond, very interesting critter.  I have not seen any beaver 
activity though (could have been a wood rat or muskrat).

Bob Hislop
Walnut Creek