Popular with hikers, skiers, and birdwatchers, Pleasant Valley Preserve in Lyme, Conn., offers 235 acres of land with 3.9 miles of trails that wind through wetlands, woodlands, and open fields with frontage on the Eightmile River. A highlight of the preserve is its array of vernal pools, temporary bodies of water that are integral to the lives of a wide array of species, and ideally viewed in the spring.

By definition, vernal pools do not have a permanent above-ground outlet. Formed by retreating glacier ice or human disturbance, these shallow depressions fill with meltwater and gradually empty throughout the spring, generally becoming dry by late summer. The pools do not support fish due to this periodic drying, making them prime breeding grounds for organisms that would otherwise be eaten by fish, such as salamanders and fairy shrimp. These organisms are called "obligate" vernal pool species, because the pools are crucial to various parts of their life cycle.

To explore Pleasant Valley, start at the entrance of the preserve, off Macintosh Road located off Route 156, and completed a circuit of the 0.4-mile Red Trail along the Eightmile River. Keep an eye out for woodland birds such as the cerulean warbler and mammals such as river otters. The river is also teeming with native trout and freshwater mussels.

Turn right onto the Blue Trail to meander through the preserve's wetlands (0.5 mile). Here, you may see wood frogs, spotted, marbled, or Jefferson salamanders, or small crustaceans called fairy shrimp in the three bowl-shaped vernal pools that the trail winds around. These obligate vernal pool species are typical of New England, and are a direct indication that a body of water is a vernal pool. While fairy shrimp spend their entire lives (only a few weeks) in the pools, wood frogs and salamanders typically live in upland forests, migrating to the pools only to mate and lay eggs.

Turning right onto the Green Trail, gradually ascend to the top of the ridge, where you will find an overlook. A complete loop 2.75-mile loop of the Green Trail will lead back to the entrance of the preserve.

Distance: 3.7 miles
Info: The Nature Conservancy; Lyme Land Conservation Trust