north Moose, Alces alces, in the natural environment swamp. Biebrza marshes National Park. The largest mammal hoofed on swamps. Moose, Alces alces, in the natural environment swamp. Biebrza marshes National Park. The largest mammal hoofed on swamps. Moose, Alces alces, in the natural environment swamp. Biebrza marshes National Park. The largest mammal hoofed on swamps. Moose, Alces alces, in the natural environment swamp. Biebrza marshes National Park. The largest mammal hoofed on swamps. European Northern lapwing field bird, Vanellus vanellus, in Biebrza national park.