Many researchers and amateur naturalists keep track of dates for the first robin of spring, the first peepers or ice-out on ponds, and such records can offer decades of data on the timing of plant and animal life cycle events known as phenology.
Many researchers and amateur naturalists keep track of dates for the first robin of spring, the first peepers or ice-out on ponds, and such records can offer decades of data on the timing of plant and animal life cycle events known as phenology.