Monday, December 12, 2011
French Creek was up, and a little muddy. It ran bank full and looked more like a flat coastal plane stream in this section rather than the rolling piedmont stream I expected. I didn’t think I would find much living among the unconsolidated sandy bottom. There didn’t seem to be much habitat structure from my stream side perspective, and lack of habitat diversity usually means a lack of aquatic diversity. But still I suited up, zipped my drysuit closed, squeezed into the wetsuit hood, sealed my mask and slid into the smooth water.
French Creek flows through Crow’s Nest Refuge, one of the many preserves managed by the Natural Lands Trust ( www.natlands.org ). The 612 acre Crow’s Nest preserve is adjacent to the Hopewell Big Woods which includes French Creek State Park and the Hopewell Furnace National Historic Site. This preserve complex forms the largest expanse of forest in south eastern Pennsylvania and together they protect, 73,000 acres, which should protect a lot of stream. I expected this section of the French to be dazzling.
The creek is deceiving. It’s not very wide, and while the stream is small in stature, it is great in force. Before I could get my bearings, the current carried me ten feet. I sailed over a sandy bottom with four foot holes carved into clay that edged the stream. Occasional logs and stumps tried to snag my dry suit. A shell caught my attention. I stopped, spun around head up into the current and swam against the flow. Sure enough, there tucked halfway into the sand was a young unionid mussel. This was a great find. Not that unio's are endangered, but freshwater mussels as a class are one of the most imperiled group of North American fresh water organisms. Many unionid mussel species are common though they aren’t as abundant as they were a few decades ago and they are struggling in some rivers like the Susquehanna. There doesn’t seem to be any recruitment of young Eastern Elliptio mussels into the population above the Conowingo dam. A population that isn’t recruiting or producing new members is destined to collapse, so it seems just a matter of time before elliptios disappear from the Susquehanna. We think this is because juvenile eels can’t make it past Conowingo on their upstream return to the river, and eels, we think, are essential to elliptio reproduction. The female mussel produces glochidia and spits a spider web of them into the water and substrate. The glochidia latch onto the eels when they pass through the web and start their lives as parasites. After four weeks, the glochidia drop from the eels and settle into to the bottom of the river as baby elliptios where they will live, possibly for the next 100 years. Knowing the complex and intricate reproductive biology behind this juvenile makes me appreciate its presence that much more. I snap a few pictures and continue to let the current carry me where it will. I never know what lies around the next bend, in the next hole.
A school of chub scatter for deeper water when I pass over, and I am positive at least one of them was a trout. A small fish darts for the scant protection of a small rock. I figured it was a tessellated darter, since it stayed on the bottom, and kind of hopped the way darters do. But as I took some shots I noticed that it had a different body type than a darter. I’m not sure what this one was, but I don’t think I have it yet.
I collect pictures of fish. It’s kind of like an aquatic life list. But it’s more than a collection. Each photo is a strand in the connection I have with streams. Each picture represents a trip, a stream and species that I affect through the choices I make, and who in turn affect me through life affirming experiences I share with them. Everything we do affects water quality, and I am grateful for organizations like Natural Lands Trust who choose to preserve land, which protects water. I came home satisfied and fulfilled. I got another one that I didn’t have, and as usual, witnessed the unexpected hidden from view in our streams. This section of French Creek was dazzling, and I can’t wait to come back.