One can imagine the muddy, silted shoreline where prehistoric animals of all sorts would come to seek water, food, or a cool resting place...
The Atreipus (Ornithischia) lived 225 million years ago and whose remains are found across North America, including New England.
The Atreipus is considered to be related to the larger dinosaur group, the Ornithischia - an extinct clade of mainly herbivorous dinosaurs characterized by a pelvic structure similar to that of birds.
Ornithischians with well known anatomical adaptations include the ceratopsians or "horn-faced" dinosaurs (Triceratops), armored dinosaurs such as stegosaurs. There is strong evidence that certain groups of ornithischians lived in herds, often segregated by age group, with juveniles forming their own flocks separate from adults.
Some were at least partially covered in filamentous (hair- or feather- like) pelts, and may have had primitive feathers.
These tracks are commonly found along side those of Dilophosaurus (Grallator) famous from the Jurassic Park films.