Along the banks of a shallow marsh a predator goes on an early morning patrol, keeping a lookout for its favorite prey. Ripples break the water’s surface and catch its attention, very carefully it wades out past the shoreline. Weighing nearly 1.9 tons its feet sink into the soft mud and detritus of the bottom as the water coolly laps against it’s scaly legs. Leaning forward it silently stares, looking for any signs of life. In an instant the silence is broken by the sounds of panicked splashing and the spray of water mixed with blood drips from the foot long claw that has hooked its way through a mortally wounded fish.
That massive claw was the first evidence found by a human in what would eventually become known as the Weald Clay Formation in Surrey, England. It was discovered in 1983 by British amateur fossil hunter and plumber, William J. Walker and is the first theropod dinosaur found to show direct evidence of eating fish as part of it’s primary diet. Fish scales found in the stomach region suggest it was ichthyophagous, though there is also evidence of the bones of a juvenile iguanodontid, suggesting it was not opposed to at least scavenge on other prey.
Baryonyx walkeri was not a small animal, measuring at up to 33 feet by some estimates, it was still dwarfed by it’s much larger African cousin, Spinosaurus aegyptiacus, who’s remains also suggest a piscivorian diet, primarily feeding on large fish. While Baryonyx had a similarly narrow snout to its famous relative, with conical teeth adapted for grasping struggling prey, superficially resembling that of a crocodilian, it is thought that it utilized it’s massive claw positioned on it’s first finger to hook fish, possibly flinging them out of the water onto the shoreline like modern Grizzly bears.