The Clearlake Oaks - Glennhaven Catfish Derby has been held annually for over forty years.
The event is held on approximately the same dates in May, and arguably attracts the most effective catchers of Catfish, so I think that the time series data reflects something real.
But I'm not sure what, exactly, it reflects!
I got a copy of the data on fish that have been weighed in going back to 2002. And made some graphs.
