much depends on what you want to see and how far you will drive outside of those cities
on the NW side of Orlando is a good spot called Wekiwa Springs State Park - good place for limpkin
closer in you could try Clear Lake Park or Orlando Wetland Parks (see Orlando city parks web site)
Nature Conservancy's Disney Wilderness Preserve is a bit south of Orlando and has some good hiking trails
near the above, Southport Road in Kissimmee (use google maps or similar) is a good drive for some open-country species, loggerhead shrike is possible (or maybe not, in September)
if you consider driving the back way from Orlando to Ft L, consider going via the Archbold Biological Station in Lake Placid, this is the best area to see Florida scrub-jay
I don't know Ft L specifically, but of course going down to the everglades has lots of possibilities