Don't let summer slip by

Don’t let the summer pass you by…

Don’t let the summer pass you by…

Headed into August and pretty good here on Montana’s Mighty Mo.

A great hopper year. Not always a great hopper river. In fact, rarely do the fish respond in the manner they seem to be behaving summer ’22. Quite good really.

The Trico hatches will continue through this month and we will witness some killer spinner falls. The PMD’s will continue to fall until they don’t. Seem to be hatching int he dark? I cannot corm, but our belief has always been that they must hatch sometime during the 24 hour cycle, and consequently fall during the daylight hours. Or, do they fall at night as well. We don’t know that but there is some interesting speak about this here below…

noun, plural: diurnal rhythms
A biological rhythm that primarily express a periodicity during daylight hours


Biological rhythms pertain to the synchronized cyclic pattern demonstrated by an organism as its response to a particular stimulus. Biological clock that synchronizes with biological rhythm may be endogenous or exogenous. An endogenous type is one in which the internal biological clock is the one that controls it. An exogenous type is one that which involves an external cue, (i.e. zeitgeber). There are the different types of biological rhythms: circadian rhythms, diurnal rhythm, ultradian rhythms, and infradian rhythms.1

A diurnal rhythm is a biological rhythm that is synchronized with the day/night cycle. It may or may not be a circadian rhythm. A biological rhythm is considered a circadian if these three criteria are met: (1) an endogenous free-running (approximately) 24-hour period, (2) a rhythm that is entrainable, i.e. capable of phase reset by environmental cues and synchronization to the 24-h day, and (3) exhibiting temperature compensation.2
An example of a diurnal rhythm is the release of microfilariae of loa loa into the peripheral blood predominantly at daytime.

Whether this behavior is associated with any of the 4 definitions seen above, we will let you do your own research. Ultradian Rhythms are shorter than the 24 hour cycle while Infradian Rhythms are longer than the 24 meter. Couple this with Endogenous or Exogenous facotrs and you may have a theory. We think we do? Or certainly have a guess.  Having not sep[nt a 24 cycle not he river,  we cannot say for sure.

The question remains is when the bugs hatch that we may not see, to create the occasionally epic PMD spinner falls we witness during the day. And not the spinner fall from the late in the day hatch of smaller PED’s. Or whatever that late afternoon emergence is. It’s generally hot, and most anglers are taking the afternoons off to rest their baked heads and frequently warm water conditions.

But don’t let this August slip by. We can have great spinner falls int eh am. Good bite before noon on terrestrials right out of the gate in the morning as well. Great hatches here on the August River. Weeds in the water column yes. Lesser number of anglers in general. Weekends packed with tubers. Go early daily, including the weekend sessions. Knock off about noon or 1pm. Nap, head back out late, or head over to Izaak’s for an afternoon cold local draft, a hand made cocktail from Scotty, or a Rib Sampler from Chef John.

Call the shop today 406-235-3447 to get your August visit squared away with our crack booking agents. We are here enjoying the month slip by. Wee are looking for cooler weather after this damn hot weekend has passed. The temps will fall below the century mark. Ahhh, yes we look forward to that day, soon.

August, Caddis, Fish August, Hopper, PMD, Spinner, Terrestrial, trico
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