Glaciated Triassic Lowlands

On July 10, the Passaic Valley sewage treatment plant discharged twice its permitted load of oxygen-depleting organic waste into the lower Passaic River. The timing could not be worse: midsummer, when warm water holds the least dissolved oxygen and aquatic life operates with the narrowest margin of survival.The lower Passaic has been under federal impairment listings for decades. The hard-won recovery that has come since the Clean Water Act — cleaner water, returning fish — is real but precarious. A spike like this in July, when conditions are most fragile, can undo months of incremental improvement and push sensitive species toward the edge of their tolerance.

The air sits in unhealthy territory today — ozone at 108 on the air quality index, forecast to climb to 110 tomorrow. Urban heat and vehicle exhaust are cooking together into a familiar haze, the kind that fills lungs and reddens eyes by afternoon.What matters ecologically is less visible. Trees absorb ozone through the same stomata they use to breathe and photosynthesize. At peak growth in summer, when those pores are wide open, ozone penetrates leaf cells and damages the walls that hold them together, weakening the tree's ability to produce energy and move water. The urban forest planted over decades to cool this city — to mitigate the heat island created by asphalt and concrete — is being quietly harmed by the very combustion that made such cooling necessary in the first place.

Along the brackish edges of the Hackensack Meadowlands, the tidal marsh grasses stand full and green in the longest days of the year. The water is warm. The mud at the marsh edge holds heat through the night. And on the sandy berms and upland margins that border these wetlands, female diamondback terrapins are emerging from the water to nest.The diamondback terrapin is the only turtle in North America that lives exclusively in brackish water, the mix of salt and fresh that defines estuaries like this one. She spends most of her life in the tidal creeks and coves of the Meadowlands, eating periwinkles, fiddler crabs, and mussels, moving with the tides. But in early summer, something shifts. Females become restless and begin to move toward shore. They are looking for dry, sandy, well-drained ground, often above the high tide line, where soil temperatures are warm enough to incubate eggs. A female may travel several hundred meters from the water's edge. She crosses roads. She pushes through beach grass. She excavates a flask-shaped cavity with her back feet, deposits four to eighteen eggs, fills the nest in, and returns to the water. The whole process can take less than an hour.What makes this moment ecologically significant is how exposed it is. In the water, a terrapin is difficult to catch. On land, she is slow, conspicuous, and committed. Common grackles and black-crowned night herons, both present along these wetland margins right now, are capable of taking hatchlings. Raccoons and foxes find and excavate nests with regularity, sometimes destroying a high percentage of eggs in a given area. Roads are the other pressure. The sandy, elevated ground terrapins prefer for nesting often sits on the far side of a road from the water, and females are struck by vehicles during the crossing. In places where terrapin populations have been studied along the northeastern coast, road mortality of nesting females has been one of the primary drivers of population decline, because females reproduce slowly. A female terrapin does not reach sexual maturity until she is seven to ten years old. She may live for more than twenty-five years. Each adult female lost to a car represents decades of potential reproduction removed from the population.The eggs themselves incubate for roughly sixty to seventy-five days, depending on soil temperature. Warmer nests develop faster. The sex of the hatchlings is also determined by temperature during a critical window mid-incubation: warmer conditions produce more females, cooler conditions more males. Nests that receive full sun through late summer will skew female-heavy. This temperature-dependent sex determination means that the aspect and shade cover of a nesting site shapes the population's future composition. When hatchlings emerge in late summer, they are small enough to fit in a tablespoon. Many move toward the water immediately. Some overwinter in the nest and emerge the following spring.The Hackensack Meadowlands hold one of the more significant terrapin populations remaining in the region. The estuary provides the right combination of brackish tidal habitat and upland nesting areas, though development has reduced and fragmented both. Terrapins here share their wetland margins with red-winged blackbirds singing from the phragmites tops, with great blue herons standing still in the shallows, and with ospreys working the open water above. All of these species are part of the same tidal system, drawing on the same productive estuary in different ways. The terrapin's role is particular: she moves nutrients and energy between the water column and the upland, and her eggs, whether they hatch or are predated, become part of the terrestrial food web above the tide line.If you are near any of the tidal margins around Jersey City right now, look at the sandy edges, the gravel shoulders near marsh, the dry elevated ground above the water. A nesting female leaves a distinctive track, a wide drag mark with alternating flipper prints on either side. The morning light is still low enough to cast shadows across the ground. You might find one.

Spotted Lanternfly nymphs (Lycorma delicata) are actively feeding on both sides of the Hudson this spring — a stark contrast to six years ago when the first individuals appeared here. What began as a curiosity has become a permanent fixture across the region.The lanternfly's success owes much to the landscape itself. Tree-of-heaven (Ailanthus altissima) lines every weedy margin from Jersey City to Lower Manhattan — an aggressive non-native that provides unlimited food for this pest. The combination is ecological opportunity in its starkest form.There is still a narrow window for intervention. At this nymphal stage, before they develop wings and disperse, the lanternflies remain largely vulnerable to targeted management. Once they fledge in late summer, control becomes far more difficult.

The sun sets late over the waterways near The Heights, leaving a long dusk that stretches into the blue hours of early summer. This is when the Black-crowned Night Heron begins to move. From the shadows of the sycamores and maples along the water's edge, these stocky, pale gray birds emerge to take their positions in the shallows. Their thick necks are drawn close to their bodies, and their bright red eyes scan the surface for the slightest movement.Early summer brings a surge of life from beneath the water. Mayfly nymphs, dragonfly larvae, midge pupae, and caddisfly cases that have spent months or even years developing in the mud and vegetation of ponds and slow-moving streams are now ready to transform. They rise toward the surface in waves, breaking through the water tension to shed their aquatic skins and emerge as flying adults. This emergence happens most intensely at dusk and into the night, when predatory fish are less likely to see them and when cooler air temperatures help preserve their delicate wings. The timing could not be better for the night herons, who are most active in these same twilight hours.The Black-crowned Night Heron is built for this kind of hunting. Its eyes are positioned to look forward and down, giving it binocular vision to judge distances accurately in low light. When an emerging insect breaks the surface or a larva moves through the shallow water, the heron strikes with startling speed. Its neck, compressed like a spring, shoots forward and the sharp bill pierces the water with barely a splash. The bird swallows its prey immediately and returns to its motionless stance. This is not the patient, slow-motion hunting of a Great Blue Heron in daylight. This is quick, precise work that takes advantage of a brief window of abundance. The aquatic insects are most vulnerable during their emergence, when they must reach the surface, split open their larval cases, and pump fluid into their new wings before they can fly. Those few minutes of transformation are when the night herons feed most successfully.The relationship extends beyond individual hunting success. These nocturnal herons help regulate aquatic insect populations at a critical life stage, and their feeding concentrates nutrients from the water back onto land through their droppings. The insects themselves are completing an ancient cycle, moving energy and minerals from the aquatic environment where they developed into the terrestrial world where they will mate and lay eggs. As the last light fades from the western sky and the first stars appear above the city, listen for the harsh calls of the night herons as they establish their hunting territories. The water around you holds this same emergence, this same patient hunt, this same movement of life between worlds.