#1: Many people keep native species outside with little trouble. With some minor modifications such as a water heater, a basking spot, etc. you might keep a non-native species outside for most if not all of the year. As you are a herp owner, you understand that if you met teh requirments of the animal it should do well. One final note on keeping a turtle outside. DOGS! Dogs like turtles in the I want to eat you sort of way. So make sure that the turtle is inside an enclosure that is safe from dogs, rats, coons, ect. I had 2 turtles in my fenced backyard and the meter reader left teh gate open one day and I came home to shells with teeth marks. It was a tragic way to learn this lesson.
#2: turtles do eat fish. They need to be small enough to kill, however I have witnessed 3 - 4 turtles gang up on a bigger fish to eat it. I do not recommend that be the only component of their diet. You should give them some fruits or veggies. One recommendation if you are going to leave them outside is to put a couple small fruit/veggie plants inside their enclousure. The bushes will give them a place to hide and thermoregulate in the summer and feed them automatically in season.
#3: I would not get a turtle now if your lake has ice on it. It also leads me to believe that it may get cold enought that there are no native species of turtles in your area. That said you might be able to leave them outside 10 months out of the year and bring them in the 2 coldest months. Thus you will need to make sure that you cane accomodate to pond sized turtles inside. I would recommend a 90 - 100 gallon tank with 60 - 75 gallons of water if you only have one or two [rule of thumb is 10 gallons of water for each inch]. Then food, a filter, a light, the whole nine yards. The good news is that you will probally only need to really clean it once, when you take it down for the winter.
One personal note: I like my turtles inside where I can watch all their antics. It is so much fun for me to come home and be entertained by the latest goings on in the tank. Out of sight out of mind, inside you may connect more and find them more enjoyable.
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Joshua M Guillemette
1.1.0 Children [Deven 10 & Hailey due June 1]
2.1.0 Cats [Micah, Judo, & Elizabeth]
1.0.0 Bunny [Bugs]
1.0.0 Red Belly Slider [Bernulli]
2.0.0 Yellow Belly Sliders [Maxwell & LaPlace]
0.0.2 Cumberlands [Pascal & Joule]
1.2.1 Red Ear Sliders [Kepler, Napier, Gauss, & Kelvin]
