Hi bthomas! How ya been?
I live in NYC (South Brooklyn, close to Sheepshead bay & Coney Island, to be exact, which geographically is on the west end of Long Island) and have 6 and 1/2 relatively large rooms in my apartment, the smallest of which comfortably fits ALL of my snakes (4 separate vivs of 55 gallons each for my adults & yearling and over 20-something, shoebox-sized, sealable containers for my hatchlings). This room is the only one in the house without air-conditioning although if I simply open the door it can be cooled off within minutes (it used to be my office when I saw patients at home - I am also a licensed psychotherapist - but now since I have a separate office off the premises, in addition to four different places I work at during the week, I only use it sporadically to work in as it is mostly used as my snake room).
That being said, I find that due to the heat & humidity summers in this part of the country generate, I can literally turn the heaters off in early July and not even need them again until late September or early October and my snakes would all probably be fine. However. being slightly obsessive-compulsive (which CAN be adaptive if one doesn't literally go overboard!), I try to maintain mini-eco-environments in each of the large vivs so as to prevent any significant dip in the temperature. While I would rather my snakes be a little cool as opposed to TOO hot, I try to ensure that they have the appropriate heat available following every meal for at least 36-48 hours afterwards. If the room is already relatively warm, the heaters are unnecessary, but there IS a thermostat in the room which will kick all the heaters on should the ambient temp dip below 77 degrees. This doesn't always ensure that each viv has the most efficient & effective and optimal temp gradients inside (they are almost always at least 5 degrees warmer) but there isn't a significant deviation from optimal conditions and any and all of my enclosures are an improvement from how conditions would be for any cornsnake living in the wild, for certain. However, the hatchlings' enclosures rely solely upon the ambient heat in this room. Since I never plan on keeping any hatchling past 2-3 months and most should have new homes by 6-8 weeks, I don't foresee any problems and can always temporarily house any of them in one of several 10 gallon tanks I have as back-ups, all with their own dedicated heating devices. (One of the benefits of being a hoarder in some respects, because I kept around most of the setups I used for different reptiles I have kept in this room for the past 15 years or so and even have equipment stored which is sill good after 25 years!).
While a temperature gradient is optimal for cornsnakes to be able to thrive, in my opinion, everyone has to assess his or her own individual situation and capabilities. If I weren't able to provide a minimally optimal environment for my little sneaky ones, from the adults and my yearling, on down to every hatchling, I would not have the ability to engage in this hobby at this time in my life (there was a period of my life, from the late 1980's to the late 1990's, during which I was unable to care for ANY pets at all, especially while working and going to school both full-time and while living in a studio apartment in Manhattan which was so small, that when someone rang the front doorbell, the toilet bowl would simultaneously flush!).
I believe everyone should have to take these things into consideration prior to making the commitment to care for another living thing, something even as easy to care for as a corn snake. For while they are relatively easy to provide and care for, the location in which they are kept can be a challenge as discussed in this particular context. I think if everyone literally practiced taking care of their corns as to the way Karl delineates, there would probably be a lot more healthy & thriving corns out there with a significantly reduced amount of health problems. Admittedly, not even I have been able to maintain my cornsnakes on THAT level, but I am not far enough away from it to be unable to provide an excellent quality of life, in my opinion. I supervise and care for my little ones very intensely, spending an average of 2-3 hours daily with them (the fact that I only sleep 4 hours a night actually helps, as I also try to run for an hour and a half to two hours daily, on a typical day, and four days a week I'm working about 12 hours a day, so the time varies between specific days). But basic, sound husbandry practices can prevent many long-term and chronic health & behavioral problems in our little sneaky ones.
At the very least, it is all good food for thought!! Everyone who houses snakes should think about this before taking on snakes as pets and from time-to-time, to ensure that they are doing the right thing, in my humble opinion.
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