A new moon sets on March 27, and the days grow longer by about a minute each day as the vernal equinox slides behind us. Spring sightings include a family of great blue herons stalking gophers in the pastures around the Bear Valley Visitor Center. One of the most colorful local shrubs—twinberry—has begun to flower between the Green Bridge and the creek crossing as you enter Point Reyes, and along the north end of the…