Scratching around in old logbooks can be quite revealing, as we found out over the holiday period when we were den bound by heavy rains. Out of a dusty shoebox came a logbook marked ‘Orlando Power Station’and a crumpled folder marked “Eighty degrees”. It not only brought back many enjoyable memories but also some incredibly important info concerning water temperature, which we want to share with you. Way back when, in the ‘BM’ era (that’s ‘Before Mandela’), actually during the early seventies, we did on several occasions go bassing in the Orlando lake, a metropolitan water body that offered something that no other one in our immediate vicinity or knowledge did, namely that the power station used its water for cooling. The water was pumped through the station to cool down the generators or whatever, and then released back into the lake. This regular inflow of warm water changed the general characteristics or properties of the lake body and despite being slap bang between Johannesburg and Soweto, namely a typical cool highveld locality, the artificially warmed water supported a good head of blue kurper and bass (along with carp and barbel and whatever else people had thrown into it).

Throughout the year it was the favourite haunt of many city bound anglers – including members of the Rand Piscatorial Society who at that time controlled all angling in the Johannesburg municipal area.

Where the bass came from is anyone’s guess (we in any event never questioned their origin) and were just thankful that they were there. Those years the use of soft plastics was considered highly advanced, with baits such as the ‘Lazy Ike’, ‘Crazy Crawler’ and ‘River Runt’, and Droppen and Rublex spinners being among the most popular ones.

In those days it was an accepted strategy that in summertime we targeted the areas where the warm water had progressed across the main lake body to where it had cooled, and in winter we targeted the areas as close as we could get to the warm water outlets. That’s where the bass (and kurper) congregated, and this phenomenon cemented the conventional bassing wisdom of the time that in summer bass move to cool water, and in winter they move to warm water – and today this is still a basic strategy for beginners and experienced bassers alike.

At Orlando however we did notice that sometimes we would catch fish in the warmer areas no matter what time of the year it was, so being the dedicated, thoughtful and creative bass anglers that we were, we just had to ask: “How come? Maybe bass like water that is much warmer than we think?” It was a vexing question that led to many a discussion in our den.

Then came our very first opportunity to fly off to the States, and while Soweto burned and the discussions around braaivleis fires centred on “the urban black issue” we landed, wide-eyed and agog with excitement in New York, and then via several shorter hops to Orlando in Florida, to eventually arrive some days later at a marina on the shores of Lake Okeechobee, Florida’s most famous bass lake.

We were greenhorns when it came to arranging cost effective air travel, but we did know full well that we needed the services of a bass guide, and even then there were several from which to choose. We were soon hooked up to a guide, perhaps in his mid-thirties and to all appearances quite capable (at least his bass boat looked like a bass boat with an engine that started first go).

On our first day’s fishing in the States we met him at the docks just as the first gleam of dawn was hitting the water, and off we roared. We must have travelled several miles before he pulled up near the entrance to what appeared to be an inlet and let the boat float into it. We were all for grabbing our rods to get in our first cast in an American lake, when he stopped us. “Gotta check the temperature first,” he explained when we looked at him quizzically, rods poised. “We gotta find the warm water,” he added while dropping a thermometer attached to a length of cord over the side.

“But it’s summer, the water is warm all over!” we protested.

“Look fellas,” he answered, “relax a while and let me tell you about temperature.” And with that he gave us a mini lecture, something we have never forgotten, but never discussed in any detail in this column (until now that is, when the Orlando lake came up!)

“What do you fellas from Africa reckon is the most important factor when looking for bass?” he posed the question.

“That’s easy,” we replied in unison. “We look for structure and cover, we look for bait fish or other food forms, we also look for water depth, water clarity and temperature and also light penetration…” Not in that particular order you understand, but that is what we had learnt.

“Well lately some of those professor fellas have turned up what they reckon is the most important thing to find when you look for bass,” he cocked an eyebrow at us, “and that is the temperature of the water!”

“Here, take a look at this,” he said, pulling a crumpled folder out of an equally crumpled duffle bag. We did take a look but asked whether he’d mind if we studied it at the marina that evening and give it back to him the next morning, which he had no problem with.

Meanwhile he was busy with the thermometer. The cord to which it was attached was marked in foot sections and he was measuring the temperature from the bottom up to about two feet deep. “I’m looking for eighty degrees,” he explained, ”which is the temperature those clever fellas say is where a bass prefers to stay, no matter if it is summer or winter.”

Well, his strategy did deliver results and he took us to several spots, with that magical eighty degree being the determining factor, and we did catch full stringers (catch and release was not considered as important those days as it is now) although we only kept a few of the smaller two and three pound fish for the table. We did take note however that while he looked for the eighty degree spots they did all without exception have most of the other important features such as structure and cover as well.

So that night after a most magnificent fish dinner we pored over the folder he had given us.

It appeared that the research on which the eighty-degree finding was based had actually been carried out to determine the impact on the environment of the hot thermal discharges of nuclear power plants. Several species of gamefish were stocked in their hundreds over a period of years, all fitted with tiny radio transmitters that not only tracked the fish’s movements but also the water temperature around them.

Fortuitously the head researcher was a confirmed bass angler and he paid particular attention to the data collected as it pertained to bass, and every review of the findings showed conclusively that the bass thrived in water that was much warmer than what everyone initially believed, indeed the research clearly showed that water of 80ºF was the preferred range. The research also showed that although the bass had a wide choice of water temperatures from which to choose - from much cooler to much warmer - they consistently preferred the eighty degree areas.

The research further showed that bass followed the 80º areas closely on a daily as well as a seasonal basis, and in several instances their movements coincided with conventional bassing wisdom - such as in summer when the shallows are warmer bass anglers seek fish in the cooler, deeper water. During the research the scientists found that when the shallows became warmer than 80º the fish would move into the cooler, deeper water, but when temperatures cooled down at night to the 80º mark the fish would move back in, remaining there for the rest of the night and into the next morning until the shallows became unbearably warm again. Light was not regarded as a determining factor because this phenomenon occurred on both sunny and cloudy days, eradicating light as a controlling factor.

We’ve got more on this subject but the editor says we can continue with it in the next issue. Meanwhile get hold of a portable water temperature gauge and seek out those 80º areas. But combine the temperature with “normal” bass holding features and you’re bound to enjoy great bassing.