Apologies for coming off like I'm being secretive or exclusive. FCPhil happens to live close enough to me that those vids are directly relevant. I PM'd because, although Glenn allowed me to share some of my YT videos because my channel is not monetized, and bc I've contributed so much to this site over the years, my channel will be monetized and/or seeking support in the future. I didn't want to trespass on Glenn's good will further.
So, here's a more inclusive response to the OP.
Summer As I Currently Understand It (via "best information" I can muster):
You know, if you fish long enough, and I mean years, you'll come to realize that things come back around year in and year out. And if you peruse the internet fishing sites long enough as well, you'll recognize common themes throughout the country. One theme is the difficulty many anglers have catching bass during mid-summer. In particular, it is weekenders (with limited time and versatility), shoreline and shorebound fisherman and, interestingly, many Florida bass fishers that are most often piping in on this very subject. This latter, the FL thing, is notable to me bc it likely copies what's happening in my waters too, even though the two are distant in both climate and sheer milage. Some pithy things are, apparently, "shared" there.
Although there appear to be common themes across the bass's range -indicating shared characteristics within the species- there are regional differences I won't be addressing in this post. That's fodder for book length treatment. So... if you don't see the videos, remember that seeing the movie is not the same as reading the book. Just can't stuff as much into vids, or posts.
Also, at the outset, know that every year is not exactly the same in any given water body regardless of location, as there are many factors -many localized- potentially at work. The trick is to identify them, then figure out which are most important in the moment.
In order to understand them, I've come to see them in a hierarchical order based on the scientific literature observing/describing the species, and then ground-truthed by direct observation and fishing. At the outset one must have some handle on -if not a measure of- the accuracy of such gleaned information; human limitations and biases being expected. Scientific literature does it's best to provide controls and/or mathematical and statistical measurement, and info often acquired by technology and expertise not readily available to everyone. Angler observation and fishing tends to be quite a bit… looser. This is the playing field. As an attempt at a "control", I used horizontal retrieves in my recent videos not bc they're always the best tack, but bc they provide a rough measure of the bass' "willingness to chase" -how much energy they have to spare for activity.
My fishing is done on small heavily vegetated waters in N Colorado and I see my horizontal chuck-n-wind bass fishing takes a nose-dive when water temps surpass 80F, esp so under bright sun. Several things are at work here: Key factors are temperature, prey availability/vulnerability, and lighting.
Lighting
I’ll start with lighting because it’s more generalized in effect, influencing our fishing regardless of physiological factors at play. In short, bass have an advantage over prey under low lighting. Under high visibility conditions, prey (bluegills at least, by research and my own observations) can see bass coming from a distance and avoid them. Under low lighting bass gain the upper hand. Bass are also safer from predators themselves -especially avian predators- under attenuated lighting and thus more able to turn their attention to hunting rather than watching out for predators. Under high vis conditions, bass tend to move to safer areas such as getting closer to bottom, into dense cover, or into deeper water if available. Attenuated lighting also obscures angler’s lures, making it easier for bass to mistake them for actual prey.
Temperature
Temperature is critical to cold-blooded creatures. Biologists consider it “the master factor”. But it doesn’t stand alone. And bass in particular are known to be “labile” in their abilities to operate across temperature ranges and changes. Still bass, and apparently all LMB (including floridanus), hit their a metabolic peak (in terms of basic energy-in < > energy-out) in the low to mid 80sF. The bass’s engines are essentially hitting redline at these temperatures. This means that energy-out is peaked, which must be balanced by energy-in: Food! If they can get enough food they can show peak growth at these temperatures. If they can’t get enough food they will begin to lose body weight. In response to high heat and low food, bass will begin to limit their active periods (activity, i.e. swimming, chasing) to the most opportune hunting times: low light of night, dawn/dusk, and deep overcast; and cooler temps of night and, especially, early morning. In larger water bodies, with deep water scenarios available, many bass will drop to deeper, cooler and dimmer waters, or to areas with more food. Which makes a great segue to prey availability/vulnerability…
Prey Availability
If bass are going to afford to remain active hunters they will need a lot of food to keep their ramped up Summer engines stoked. Thus they will seek out the best food resources. If they can find a motherload of prey they will stay put. If not, they are apt to keep searching. However not all bass find the best places; Many will find what biologists call “false peaks” -areas that may not be the best in the lake but that are enough to attract and hold some bass. Some bass will find inadequate resources and must reduce activity commensurate with food resources. And some bass may find the motherload and remain active, and grow, despite high heat.
Prey vulnerability is another piece of the puzzle. Prey is not easy to catch, the result of the evolutionary arms race over time that has resulted in the body forms and capabilities of predators and their prey, alike. Each prey type and species has it’s defensive strategies that shine under certain habitats and conditions. Bluegills and other sunfishes are particularly adept at evading bass in dense cover. Shad are adapted to avoid predators in open water. Bass are both pre-adapted to these and can fine tune their hunting behavior to that prey, habitat, and conditions (i.e. learn). However, although bass have been described (and by those who should know -fish behavioral scientists) as “perfect piscivores”, they too have limitations.
Bass are known to hunt best in broken cover, where they can use the element of surprise to get close enough to prey to realize efficient capture rates. Not that bass can’t hunt in denser cover, or more open water, but conditions and individuals must be more "disciplined", if you will, and require more learning, and luck, for sufficient success. Or even better, simply have a LOT of appropriate prey available.
My Waters in Summer
So, with that background in place, in my mostly shallow heavily vegetated waters, lighting, temperature, prey vulnerability/vegetation density appear to be the primary factors. I fish at least a dozen water bodies and each vary in their make-up of course, so not every one reacts in the exact same way. But those parameters above are pretty basic to all waters.
Fishing
In general, many bass will move away from shore in summer, even in smaller waters. FCPhil, you are right there. Bluegills will drop away from the surface too as heat penetrates deeper. When shore fishing I may break out a large-spooled long casting rig to reach. However, away from shoreline reach is not all there is to it. You are right there as well.
Fishing under high heat in shallow waters often means hitting the darkest and coolest periods. If you suspect high heat affecting bass activity, check for a "first light bite" -the coolest time of the day. And I mean first light -it may be over by the time the sun hits the water. And the fishing can be wild! Keep track of body condition of the bass you catch. Thin bass can indicate the fish are not getting fed well enough to keep up with their metabolism.
If you want to fish chuck-n-wind you may need to focus on low light and cool periods. Praying for rain -a good dark cold front- can help. I don't know if you've been out much lately, but that's exactly what we've been getting here in CO the last couple of weeks. Jump on it, man! Otherwise, under heat and sun, you may be better off fishing vertical presentations, and closer to bottom, in your daytime fishing, such as jig-worming ("Shaky") and drop-shot for neutral bass, or flipping in heavy cover.
Hopefully this helps you home in on what's important in your waters, or at least gives you some gristle to chew on toward that end.
This background will also help viewers make better sense of my vids too, as I try to keep the length of my narrations to a minimum to keep viewers from clicking away from a talking head. However, this is the cool stuff, if you ask me.
