For-Mar Nature Preserve doesn't have an astronomy club that I know of. Astronomy clubs in this area would include the Genesee Astronomical Society and Seven Ponds Astronomy Club. For-Mar had a moon viewing in March, 2018. Longway Planetarium would probably be the place for telescopic viewing. Hope that helps.
You can always call during business hours and ask them, i am not 100 percent sure. They do many activities out there all the time!
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