Four weeks, three venerable national parks, three entirely different experiences. And time to mull the future of the National Park System and its caretaker, the National Park Service.

Secretary of the Interior Sally Jewell on Thursday announced a new study showing that spring is beginning earlier than its historical average in 75 percent of the national parks examined — providing further evidence that climate change is already impacting public lands. The announcement came during a visit to Shenandoah National Park, one of the sites identified in the study as experiencing the impacts of an early onset of spring.

Shenandoah National Park, along with the Barlow family of Stanley, Virginia, will co-host the 83th Annual Civilian Conservation Corps Alumni Reunion this coming Saturday. The public is invited to meet with families and alumni and hear first-hand about their experiences. Alumni reunion events will take place at the Big Meadows Lodge Massanutten Room (mile 51 Skyline Drive) beginning at 10 a.m. with remarks from park leadership.

There are good times to go birding in Eastern forests and times that are less than ideal. I won’t say the birding is ever “bad,” because even if there aren’t any birds, a walk in the woods is never a bad thing. Still, if seeing tons of birds and hearing beautiful songs is on your agenda, avoid August. Head to the beaches to see shorebird migration.