Tuesday, December 2, 2014

Muppet Hope

The river is hairy, and the bottom is covered in long wavy olive strands. It looks like shag carpet grew out of and over everything. The usual late fall algal growth has erupted. It has been 4 years since I snorkeled here, on a day when the June air temperatures reached 80 degrees and the 60 degree water felt good. Today the air and water matched a chilly 40, and I hoped to see mussels. I hoped I would see the slightly agape shells that expose peach colored frills as the mussels filter water. This used to be one of the best mussel beds in the river and I hoped they remained. Mussels are some of the most imperiled organisms on the planet, and while that may not seem like a big deal to some people, it bothers me that we are ok with eliminating organisms that can live to be 100, and that play critical roles in how our ecosystems function. Mussels filter ridiculously great quantities of water and destroy disease causing organisms. Our health is related to theirs. It is all connected. But I wanted these mussels to be here not because of what they do for us, but because they are amazing in and of themselves. I was hoping this mussel bed would appear to be in as good a condition as it was the last time I was here. My assessment is based on non-quantitative observations, but there is still a lot of value in sticking your head in the water and just looking. The cold water freely entered my wetsuit glove and I struggled against a full and moderate current. I wasn’t sure if I would see any mussels thought the algal hair on the bottom. I started to see empty halves and saw a recently dead adult, with bleached flesh still inside the partly opened shell. Then finally I found my first faint slit in the bottom. Then a second and third and soon I was in the middle of the mussel bed. I was surrounded by Muppet looking creatures with mouths all agape covered in soft long billowing algal fur. These were all eastern Elliptios. They have a close relationship with eels, and depend on them for reproduction. Eliptios produce a web like substance full of juvenile mussels called glochidia that need an intermediary host in order to metamorphose into a mussel. Eels play much of that role for elliptios, and as an eel swims through the glochidia containing web they become infested with the parasitic bivalves. After a month, the glochidia finish their transformation and fall to the bottom as mini mussels where they start to filter feed and live out their lives that can span 100 years. For as much biological complexity and genius there is in this strategy there is a cost. If the host fish declines, so too do the chances of successfully reproducing young. And that’s what’s happening with elliptios. Eels are declining due to dams and sediments, and so the mussels are too. But today it seemed that while this mussel bed had been seasonally transformed into Muppets, it was intact, and thriving even. I found a few juveniles which is always a celebration. A reproducing population is a surviving population, and I found hope among the Muppet mussels.

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