The Hendrickson hatch (Ephemerella subvaria)
is the most awaited of the early season hatches in the east. Those who
don’t have it should cry. It’s the first big fly of any consequence on
our rivers. Sure, others hatch earlier but not in the grand style of the
Hendrickson. It’s not an easy hatch as I commonly see Blue-Winged
Olives and the Little Black Sedge come off at the same time. An
individual trout can be on any one of the life stages of these three
insects. It’s a smart fisher who knows what his trout is really eating.
In order for this hatch to really cook, the water temperature must be from
50-55 degrees F., and here that means late April to early May. This year we
have had a warm winter so I expect early April to cap the event. A few warm
sunny days will cover the stream-side vegetation with them.
This insect is found in gravel sections of relatively constant temperature
rivers. The Au Sable River in Michigan has a hatch I routinely drive eight
hours to fish. Catching trout feeding in the slow glides is my thing, the
slow glides adjacent to a riffle on a nice cool day. The flat water runs
runs where big trout and I await.
Originally published c. September 5, 2008 on Fly Anglers Online by Jim Birkholm.