It all started with a chat while kayaking. Last year my wife and I went on a kayak trip at a local Nature Conservancy (TNC) property. There were about 15 of us, including a few TNC staff, in addition to our guide. During the three hour trip, I had the chance to chat with most of the participants. One of the TNC staff told me about a trip she had just taken to another TNC property in the far western corner of Virginia to see elk and said if we were interested, to let her know and she would get us included in next year’s trip. It sounded really interesting, so my wife and I put it on our fall trip-list and, after a few coordination emails, we were headed to Abingdon, VA to see elk this fall.
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Monday, October 12, 2026
Monday, September 28, 2026
[Field Notes] Grafton Ponds Walk
Recently I had a chance to take a guided walk with Zach from the Virginia Department of Conservation and Recreation's Natural Heritage Program at Grafton Ponds Natural Area Preserve (NAP). I've talked about Grafton Ponds several times in the past, most recently this past spring when I did a bird walk with some friends.
The walk was in celebration of the 40th anniversary of the Natural Heritage Program and one of several they are doing around the state. Grafton Ponds is special because it has a large number of sinkhole depressions that collect water and then dry out annually. Sometimes called vernal pools or ephemeral ponds, this cycle of wet and dry throughout the year provides good places for amphibian to lay eggs. Fish are one of the main predators on tadpoles and eggs. Since the ponds dry out, the fish can't survive so there are fewer predators for the young amphibians to deal with. There are approximately 200 such ponds in Grafton Ponds complex with about 70 or so in the Natural Area Preserve proper. Depending on the water level, there may be three nearby ponds or a single, larger pond, making it hard to get a precise count.
The ponds form when water collects and slowly seeps through bedrock that is dissolvable. Often that is limestone. Here on the coast, the bedrock is fossilized shells from a few million years ago, part of the Yorktown formation. Appropriate since the preserve is just outside Yorktown. The ponds continually form as the bedrock is removed and fill in as more sediment fills in the ponds. Zach told us that some of these ponds have been dated to 40,000 year ago while younger ones are around 350 years old. The older ones have a lot of spruce pollen in the sediment dating from the last ice age when spruce could live here. The younger ones formed around the end of a dry era that coincided with the arrival of European settlers. The settlers at Jamestown and other early colonies had trouble finding sufficient fresh water and that is attributed to salt-water intrusion to aquafers due to the extended dry period. As the rains returned, ponds started forming again. The Europeans also removed a lot of trees. The trees pulled up a lot of rain water. Fewer trees means more water to dissolve the shells and make sinkholes.
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| Some fossilized shells found along a stream bed |
Thursday, September 24, 2026
Rising With The Tides
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| Tides from Sept 24. Data from https://water.noaa.gov/gauges/FTMV2#hg=official |
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| Usually there is a narrow creek here and lots of marsh grass |
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| Not the type of watering you want for your garden |
My usual first stop is a boat ramp near home. Even though the city recently redid the parking lot, the entrance was flooded. After finding a dry place to park, I walk along the edge of the water occasionally recording the precise location in an app. I can record a point without really breaking stride making data collection about as easy as taking a walk. And in many places, I can do it without even getting my feet wet.




