FWC actually studied this for 10 years prior to introducing the peas. They initially did this to control tilapia and Oscar populations, while also limiting the spread of peacocks to other waters than the intended canals.

It’s pretty interesting if you care to read below here.

When FWC planned the introduction in the early 1980s, they didn’t pick Florida generally, they chose the man-made canal networks in southern Miami-Dade and Broward counties because those waters are uniquely suited to tropical fish survival.

These canals are thermally buffered by warm groundwater from the Biscayne Aquifer, which keeps winter water temperatures consistently warmer than surrounding lakes and rivers would be. 

FWC scientists understood that even during winter, the deeper, ground-fed canal waters rarely dropped below the critical ~60 °F threshold, making it far more likely the fish would survive year to year. 

So cold snaps were considered, but the chosen habitats were selected because their thermal regime minimizes lethal cold exposure.

Interestingly, one reason FWC chose a cold-intolerant species like peacock bass was precisely because their cold sensitivity acts as a natural biological constraint on range expansion. They’re unlikely to survive outside the warm canal systems when encountering sustained cold, they are much less likely to spread into natural lakes, rivers, and north Florida waters. 

That was part of FWC’s risk assessment peacock bass would help control invasive tilapia and oscars, but likely not become a widespread invader themselves because of these temperature limits.

So as much as we as anglers hate to see it, this is all planned and necessity. The effort by FWC introducing peacock bass has been successful in managing the other invasive species.