Yesterday we made a trip to Mt. Vernon. It was perhaps a mistake at this time of year as the heat and humidity kicked our ass. On the way to and from Mt. Vernon is the George Washington Memorial parkway, a park maintained by the National Park Service. It has great places to picnic along side the Potomac River. It also has a very active biking and walking path.
We also found these fresh water snail shells. The river bank was covered in them. They are about three to four inches large.
It turns out the snails are a recent inhabitant of the river. They are called a Mystery Snail and were bought from Asia in the 1890's first to California and by the 1960's they finally made it to the Potomac. The shell is not very colorful as it is a dull olive color. Asians consider them a food source but I saw no one trying to harvest them yesterday. They are considered an invasive species.