March can be a frustrating time in western Pennsylvania. Spring weather intersperses with winter temperatures, teasing residents with the promise of warmth and sun one day only to have the next day requiring winter coats once again. Buds on the trees start to swell, and if the warmer temps stick around for too many days in a row, they may even start to grow leaves before the final snow of winter falls. Other signs of spring include the return of migratory birds, such as turkey vultures, killdeer, and red-winged blackbirds. And the spring peepers, a tiny native tree frog, have been singing for several days in the wetlands now.