U.S. Route 7 Bypass
Habitat Creation Areas
Beginning in 2006 a six year study was initiated to evaluate the impact of the then proposed U.S. Route 7 Bypass in Brookfield, Connecticut and success of the proposed mitigation package on a population of Eastern Box Turtles. In order to evaluate the highway impacts and success of the mitigation initiatives this project was conducted in three Phases:
Phase One monitoring was conducted from 2006 to 2008 prior to construction activities.
Phase Two monitoring was conducted in 2009, during construction activities.
Phase Three monitoring was conducted from 2009 to 2010 after construction of the U.S. Route 7 Bypass was completed.
As part of the mitigation package for the U.S. Route 7 Bypass two early successional habitat creation areas were designed and constructed:
0.45 hectare early successional creation area designed for nesting box turtles (see below)
0.68 hectare early successional highway slope creation for general habitat (see below)
The 0.45 hectare early successional creation area designed for nesting box turtles was seeded with warm season grasses, mixed herbaceous plants and shrubs. A total of 241 plants were planted comprised of 61 shadblow serviceberry (Amelanchier canadensis), 155 sweetfern (Comptonia peregrina), 9 red cedar (Juniperus virginiana) and 16 old field common juniper (Juniperus communis var. depressa).
The 0.68 hectare east side highway slope creation area was planted with warm season grasses, mixed herbaceous plants and shrubs. A total of 633 plants were planted comprised of 60 shadblow serviceberry (Amelanchier canadensis), 195 sweetfern (Comptonia peregrina), 189 common juniper (Juniperus communis var. depressa), 63 cottonwood (Populus deltoides), 15 common spicebush (Lindera benzoin), 42 black willow (Salix nigra), 39 red osier dogwood (Cornus sericea) and 30 speckled alder (Alnus rugusa)
Turtles were observed using the creation areas for the first time during the construction phase in 2009. The 0.45 ha creation area saw increases in use from 25 observations during construction to 89 observations post-construction, with a 50% increases in the total number of turtles using the site – from 8 during construction to 12 post-construction. In addition to being used as general habitat, the creation area also was used 5 times for nesting between 2009 and 2011 with a 57% hatching success rate.
The highway slope creation area, saw a steady increase in use from 61 observations during construction to 229 observations post-construction, in addition to a 467% increase in the total number of turtles using this area from 3 during construction to 17 post-construction. Both creation areas were used for basking; utilizing the randomly dispersed grassy and herbaceous areas during cooler periods, with a high affinity towards crown vetch; while seeking shelter during warmer periods under the clumped shrubs, brush piles and thick grassy/ herbaceous areas.