Wednesday 1st April
Click to play Read by Matthew
Bones - the skeleton. Birds need to be light in weight. They use a lot of energy flapping their wings to take off and fly. So the bones that make up a bird's skeleton must be light as well as strong to do their job. A bird’s main limb bones are hollow, with special struts inside to strengthen them. This makes them strong. Have you ever tried to see how much weight a paper tube can hold? Why not try a few paper tubes stuck together in a bundle? Perhaps you could make your own paper tubes from newspaper? or use paper drinking straws? Finding out how strong tubes can be will help you understand that a bird's skeleton is light weight as well as strong.
The largest common bird in Britain is the Mute swan with a wingspan of 223cm and weight of 11.5kg (male). The smallest bird in Britain is the Goldcrest and Firecrest - tiny birds with a 14cm wingspan and only 6g weight. The Firecrest is rarer than the Goldcrest. I often hear Goldcrests singing at this time of year. A high pitched - "zezezezezee" from tress and hedges where they search for insects flitting from one branch to the next - they don't keep still!.The world's largest living bird is the Ostrich that can weigh 136kg and 2.5m tall. The smallest bird in the world is the Bee Hummingbird of Cuba - weighing about 1.8g and only 5.7cn long! The biggest wingspan is the amazing Wandering Albatross, 3.6m wide! Albatrosses, Albatross Pictures, Albatross Facts - National Geographic