I also believe walleye populations exploded in the 50-70's because they were invasive (being stocked) and no real predators untill they were completly acclimated to the kawartha's IMO.
otherthings to consider, the lakes has we know them have been around since 1850's or so when dams locks started going in current model of trenst severen is what 1913? with the damning gull, missiasuga, north river and crowe systems.
Anyone been noticing the a mount of silt build up in the lakes over the last several years? laydowns i would fish on in goose are buried some of the shoal areas nice fine layer of crud on them, weeds growing in new places different weeds altogether in other, these lakes are changing and evolving at all times.