Here are some of the conservation areas / organizations I've been involved with or a frequent user of, in order from more involved to less involved. You can also read my blog where I muse, rant and vent.
The Toad Detour in Roxborough, Philadelphia, Pennsylvania is an annual spring activity to keep toads from being swished on the road by cars. I've been involved for 10+ years and this website hosts a prediction model designed to conserve volunteer resources. The toad detour is sponsored by the Schuylkill Center for Environmental Education.
The McKaig Nature Center in Upper Merion is a 90 acre preserve in an otherwise densely developed area. It is a public / private partnership. It is very close to my house. I have volunteered there in the past and am volunteering there again in my retirement. I am curently doing an invasives renewal project, mostly on the newly acquired section of the park. The park ranger there encourages all sorts of group activities, which is a very refreshing attitude. There are trail races, orienteering events, scout activities, school activities, etc. all with very little required in the way of paperwork.
The Queens University Biological Station in Rideau Lakes holds thousands of acres of wilderness, shorelines and abandoned farm land. As I paddle through lakes with protected shorelines, ride through the Cataraqui Trail or hike through the Rideau Trail I appreciate the untouched beauty of the wilderness. I've been attending some of their Wednesday night seminars and hope to help out QUBS in the future.