you might want to call before you go:
main # (716) 354-9121
reservations # (800) 456-2267
some info I found for you:
Reservations
Arranging a stay at a New York state park is easy! Reservations can be made from 1 day - 9 months in advance by calling toll free 1-800-456-CAMP or www.reserveamerica.com. For spur of the moment trips, rentals are also available on a walk-up basis.
Reservations will be taken as follows:
* From December 1 through mid-March:
* Monday-Friday: 9:00 a.m. - 5:00 p.m.
* Saturday and Sunday: 9:00 a.m. - 12:00 p.m.
* From mid-March through Labor Day:
* Monday - Friday 8:00 a.m. - 8:00 p.m.
* Saturday and Sunday 9:00 a.m. - 5:00 p.m.
*
* From the day after Labor Day through November 30:
* Monday - Friday 9:00 a.m. - 5:00 p.m.
* Saturday and Sunday: 9:00 a.m. - 12:00 p.m.