The Hudson River Research Reserve participates in the PhenoCam Network, a cooperative continent-scale phenological observatory with monitoring stations throughout the world. Changes in vegetation phenology across a wide variety of ecosystems is tracked using digital cameras which upload photographs to station webpages. 

If you have visited the Norrie Point Environmental Center in summer, you may have observed a dense mat of floating plants within the cove. At other times of year, these plants may have appeared sparse or absent – or, the river may have been frozen solid. The cove is dominated by a non-native invasive plant called water chestnut (scientific name Trapa natans), introduced to the United States in the mid-1800s as an ornamental plant. These plants produce barbed seed pods which can be observed along the shores at Norrie Point and various locations along the Hudson River. 

Researchers at the Hudson River Reserve are interested in better understanding the phenology, or the seasonal timing of plant life stages, of water chestnut in the Hudson. By collecting periodic images throughout the day, every day of the year, scientists can observe when the plants emerge in spring, reach peak density in summer, and senesce in autumn. 

Paddlers, educators, anglers, and other river recreationists can use the Norrie Point PhenoCam to see if water chestnut is present around Norrie Point. It is also useful for seeing river ice conditions in winter.