"The pine snake is one of the reasons these [passages] were installed to begin with, and we're particularly intrigued to see it," said Gretchen Fowles, a specialist with the agency's endangered and nongame species program.
The images will reveal which animals are being redirected from the dangerous road and how often, she said.
"There are some other state special-concern snakes that could be down there, but that's part of the fun of having the cameras and seeing what we see," said Brian Zarate, a senior zoologist with the agency, who also works with the animal crossings.
Eight motion-triggered cameras were set up in recent days to observe the activity under the busy highway. Other animals that may appear are raccoons, foxes and opossums.
Ten miles of wire and mesh fencing were also erected along both sides of the highway near the Frank S. Farley Rest Area in Hammonton to prevent the animals from wandering into traffic. Snakes are attracted to the warm asphalt when they look for a place to bask in the sun.
The South Jersey Transportation Authority built the tunnels and installed the mesh fences as part of a road widening project that is nearing completion. When asked how the wildlife crossings and fences are working, authority spokesman Kevin Rehmann joked that so far, none of the animals have "become scofflaws" by sneaking onto the road without paying tolls. Vehicular traffic is up 2 percent so far this summer, with more than 53 million trucks and cars barreling down the highway.
Zarate said more wildlife crossings are proposed in Waretown, Ocean County, where a new road is planned. There would be tunnels built and the road would include an overhang to prevent northern pine snakes from climbing over the edges and becoming roadkill.
And tunnels are planned under a road near the Stahl Natural Area in Bedminster, Somerset County, to protect the threatened wood turtle, a small brown creature with red or orange markings on the neck and legs, Zarate said. The four tunnels also are intended to protect salamanders, frogs, toads and other amphibians that were separated from their breeding grounds in vernal pools when the road was built.
"They would have to hop a pretty far distance to find another suitable breeding area," he said.
Not only does the environmental agency aim to keep the animals safe, but it also wants to restore habitats severed by roads and other man-made barriers, Fowles said. The fragmentation jeopardizes the animals' mating habits, gene pool, and breeding grounds, she said.
At the Atlantic City Expressway crossings, specially arranged rocks were placed into the culverts to allow terrestrial creatures to pass through them, Fowles said. She said this would assist the animals in reconnecting with their habitat.
Images retrieved from the new cameras, she said, will help the agency determine the success of these crossings.
"If we get pictures of animals going to the structures and not using them, or showing signs of avoidance, we could look into changing the design, putting soil on top of them and making them as natural as we can," she said.
Earlier this year, officials with an environmental agency in British Columbia were surprised by the images they collected at three wildlife crossings built beneath Route 93 in Kootenay National Park. A pack of a dozen wolves were regularly using the crossings, according to published reports.
"When you put in new crossing structures, you expect a learning curve - some time for animals to get used to them and start using them," Trevor Kinley, the project manager, said.
But the pictures revealed that the wolves apparently liked the crossings and used them 14 different times in the first year after they were installed.
In New Jersey, the environmental agency will be content to see a rare snake come out of hiding and slither by, especially if it is followed by a wood turtle.