Gasp
“The Gasp Reflex Loss of breathing control begins the moment water makes contact with the skin, triggering a series of huge involuntary gasps for air. If your head is underwater when you gasp, you will immediately drown. Example: Oct. 1987, Water temperature: 41°F. Fit paddler, calm waters, folding double kayak with 36" beam. Found hanging upside down in his boat, having made no attempt to exit. Not dressed for immersion.” This is a quote from Atlantic Kayak Tours which has articles on cold water safety. If the water is real cold and your not dressed for going in, survival time is apparently quite short. In the spring the air is hot and water cold so it’s hard to wear protection for immersion, float jacket ,etc. The CG has info on this, with survival tips ,like being able to get back aboard quickly, wear a hat, huddle to retain heat, don't thrash about. From a chart we have it shows : 32-41 maybe 1 hr /41-50 maybe 2 hrs /50-59 maybe 3 hrs. There is a local(I think) saying ,The 50/50 rule: 50 degrees,50 yards to shore,50 percent chance of making it! Being clipped on and using safety netting ,so it’s difficult to get overboard ,seems like a good way to enjoy the part of the season were you wouldn’t want anyone in the water.
. But, that is a long wait. You may want to spring for wetsuits for the kids. They could wear them on board and they could be used to extend the swimming season in Lake Michigan. There are numerous options and not all of them are uncomfortable. A wetsuit would certainly give a young kid a much better chance to survive an emersion, simply because it would extend the amount of time that they can survive and it would reduce the types of reactions that would happen if they fell in. Certainly, the best precaution is making sure they are safe on the boat. When I was much younger and learning to sail on a small lake in northern Illinois, I wore a wetsuit anytime I went out in any boat earlier than June and later than September. It didn't matter that there was no expectation that you could go in. Sailing a Hobie Cat meant you could end up in the lake at ANY moment (especially single-handed). db, Sauganash was my address for several years!