The weather has been good, but weeks of hot sunny weather has caused a bit of an algal bloom making the lower sections of the river pretty green and brought some of the huge filter feeding silver carp up from the lake. You can't legitimately catch one of them, although they'd probably be a lot of fun, they just cruise around like basking sharks filtering out zooplankton. I wish they'd do a better job of it though, as it'd make spotting real targets much easier.
Fortunately the river is still a bit clearer further away from the lake. The fish are smaller but there are loads of them.
It's been pretty fun, challenging fishing. At the start of the week it seemed like every eddy or backchannel was full of carp sucking seeds off of the surface. I like seed feeders, but it can be a something of a double edged sword; the fish eat seed imitating flies very readily but it's very hard to tie an appropriately sized seed pattern that will float on a hook that won't bend out on a decent carp. Seed clumps might be a workaround but they don't always seem to work as well. Berry feeders are easier but that's still a few weeks away.
The rest of the fishing I spent looking for fish in feeding in the faster water, there were plenty with air temperatures in the high thirties and water temps not much lower, the carp are at peak metabolism and many of them are hunting for a meaty meal. The shallow faster parts of this river, where the current keeps the bottom relatively clear are great for targetting these fish as they search for small crayfish, large caddis or gobies. They're also a good place to lose flies. Except for the few dry fly fish at the start of the week, everything I caught (nothing big, but a lot of them) came to a simple little zonker pattern (POD).
I like simple flies for mst of my fishing, but especially when fishing for carp in rivers near where people live; there's always some rubbish in the river that can easily grab a fly. Old bikes are pretty common in Japan, as are tarpaulin sand bags that are inexplicably the main choice for a lot of bankside and trail support around the country. Those bags eventually wash into the river and if you hook one, your fly is doomed. So, I always like it when the fish will eat that little zonker or something similarly quick to tie, and with the exception of the backstabber no other fly has held its place in my box for as long as it. It's just good, fish eat it, it can be scaled up or down for different waters (I tie them from size 1-10) and tied in different weights making it suitable for both rivers and stillwater. And the best thing, it's a 2 minute tie. Just tie on your eyes and a couple of legs stick the hook through a zonker strip tie it down at the head, fold the front ends of the legs back over the rabbit and whip finish. If you want more volume in the body, use a magnum or texas cut rabbit strip. If you're feeling really extravagant add some flashy dubbing and brush it out. So simple even Paul could tie it :D
If you fish for carp you should definitely tie them, it's as close to a universal carp pattern as I've tried.
Hook: Kamasan B200 in smaller sizes or Gamakatsu SL11-3H in the bigger sizes
Weight: lead, brass, bead chain, or glass bead dumbbells
Underbody (if you must): ice dub, craw dub or something simlar.
Body: Rabbit strip
The best colours seem to be rusty orange then black. Olive and tan can both be useful on their day but are way behind the other 2.