Title On-board 'fuel' keeps birds on the wing Degree of recognition International Media name/outlet The Times Media type Country/Territory United Kingdom Date 05/02/2001 Description The mysteries of how birds migrate thousands of miles without "running out of fuel" has been solved by scientists, who have found that some species can cannibalise their vital organs, including their livers, kidneys and skins, to generate inflight food.
Birds were thought to build up fat reserves before flight and gradually run these down, but the findings show that far more complicated changes are occuring.
The findings, published in the Proceedings of the Royal Society, have come from a team studying the 3,400-mile journey of great knots migrating from northwest Australia to China. Dr Theunis Piersma, a Dutch scientist, said that similar results had been obtained from common knots migrating to Britain.
The researchers checked the fat reserves and weights of organs in the birds before they took off on their journey north. Birds arriving in China were then screened on arrival. The team found that fat reserves were all but depleted on arrival - down by 80 per cent - but so were the vital organs, with the exception of the brain and the lungs. The birds' livers were a third of what they were before they left, as were the kidneys and intestines. Pectoral muscles, used to flap the wings, were down 20 per cent and even the heart had lost muscle, also weighing 20 per cent less.
Dr Piersma said that what appeared to be happening was that the proteins were being channelled to the heart and breast muscles at a time when the birds were heavy with fat reserves.
Producer/Author Nick Nuttall URL www.nexis.com/results/enhdocview.do?docLinkInd=true&ersKey=23_T23454961483&format=GNBFI&startDocNo=1&resultsUrlKey=0_T23455314483&backKey=20_T23455314484&csi=10939&docNo=6 Persons Theunis Piersma, Maurine Dietz
- bird migration