A Connecticut Department of Energy & Environmental Protection (DEEP) assessment determined in June that the expanded parking lot planned at The Preserve on Ingham Hill Road in Old Saybrook must make accommodations for two species of turtles designated by the state as being of special concern, as well as a bat species the state has designated as endangered.

Clearing for the refurbished lot, which will provide space for 12 cars as opposed to just five in the current one, will begin this fall.

Eastern box turtles (Terrapene carolina carolina) and spotted turtles (Clemmys guttata) are particularly vulnerable as adults because of their “late maturity and long life spans,” according to a letter sent by Shannon Kearney, a DEEP wildlife biologist, to Nathan L. Jacobson & Associates (NLJA), a consulting civil and environmental engineering firm based in Chester that has done the design work on the lot.

“Chris Taylor, P.E. of NLJA designed the parking lot for Ray Allen, director of Public Works, with advice from Dr. Matt Aresco, herpetologist, who happened to be in town visiting his parents,” explained Old Saybrook Town Planner Christine Nelson.

Primary threats to the turtles are construction vehicles, cars, illegal collection by humans, and predation. Kearney’s letter states that construction should be conducted during the turtles’ active season, April 1 through Nov. 1, in order to allow the turtles to “move out of harm’s way and minimize mortality to hibernating” turtles.

Those guidelines, however, had to also take into consideration the lactation period of little brown bats (Myotis lucifugus), from May 15 to Aug. 15. Tree removal cannot take place while the bats are lactating, so clearing for the new lot had to wait at least until the second half of August.

The lot is located between two vernal pools, shallow pools of water usually present for only part of the year that provide important habitats for plants and animals. These pools, Kearney said in her letter, have been “identified as highest priority vernal pools in The Preserve for conservation, based on the diversity of species they contain.”

This means not only that the entire construction process must be conducted carefully so as not to disturb the turtles, but that a barrier must be erected around the lot to ensure that the turtles don’t enter. A three-foot chain-link fence will be installed, topped by a safety polycap similar to those placed on fences around sports fields, “so human visitors will see it and not trip over it,” said Nelson.

The fence must be maintained on a regular basis to ensure that gaps don’t materialize at the bottom, allowing the turtles to cross into the lot, Kearney advised in her letter. In addition, paths to hiking and mountain biking trails must be clearly marked to keep human users of The Preserve from straying into the 750-foot “envelope” around the vernal pools.

“Vernal pools have the best chance of healthy persistence if less than 25 percent of their envelope is disturbed,” Kearney wrote.

The Old Saybrook trailhead, which is served by this parking lot, is one of four main lots leading into the nearly 1,000-acre open space. The Preserve’s principal entrance is in Westbrook, at 1278 Essex Road (Route 153), which has a parking lot with 30 spaces. Two trailheads with limited parking are located off Ingham Hill Road in Essex, accessing separate but ultimately connecting trails. The lot is expected to be finished and opened in the spring.