Why are procellariiform birds awkward when walking on land?

Procellariiform birds, also known as tube-nosed birds, are considered awkward when walking on land because their legs are positioned too far to the rear of their bodies. This anatomical placement prevents them from achieving the well-balanced, bipedal progress typical of many other birds.1

Because of this limitation, they are clumsy when ashore and must laboriously use their wings as props to assist with movement. While they are highly specialized for life at sea and are considered perfect aviators in the air, their physical structure makes them relatively helpless and unable to maneuver quickly on land.1