World record non-stop flight for the Bar-Tailed Godwit

By in science
Bar-tailed godwit

Bar-tailed Godwit’s make world record flights across the world.

Alaskan Bar-Tailed Godwits just look like an ordinary shorebird. Recent research however has discovered that these waders are the new world record holders for non-stop flight. Every autumn, these extreme migrators fly an astonishing 11.000km from Alaska to New Zealand without any stopovers to rest or refuel. This roughly doubles the previous maximum known non-stop distance for migratory birds.

The non-stop flight of the godwit’s is even more impressive if one takes into account that the current world-record for a manmade flying device is 82 hours, less than half that of the godwits.

Gill and colleagues (2009) used satellite telemetry to track 23 birds on their trip across the pacific. By this relatively new technique in which the position of each individual bird is sent to a satellite every six hours, the authors found out the birds need on average 8 days to make the crossing.

Bar-tailed godwit record flight

Southward flight tracks of nine bar-tailed godwits fitted with satellite transmitters.

These extraordinary non-stop flights establish new extremes for the flight performance of birds. There are birds however with even longer migrations than that of the Alaska Bar-Tailed Godwit. For example the pectoral sandpiper which flies 16000km with at least one break in between, and the impressive 24000km northbound spring migration of the arctic tern. The difference is that these birds have the opportunity to feed and rest at sea as they go and thus do not need to fly non-stop.

So how are these birds able to fly non-stop for 8 days across the pacific? Professor Hedenström assessed the unbelievable aerial feat in a interesting paper published in PLoS Biology this spring. He calculated that the birds only use some 0.41% of their body mass per hour which is the lowest value thus far for any powered animal flight. This is important because the godwits have to take just as much on board before departure to sustain them for the 8 day flight. Furthermore, it is important the birds have exactly the right body weight to size and have an aerodynamic body shape. Very crucial for the godwit’s journey is their high flight speed which makes them relatively immune for crosswinds.

Bar-tailed godwit

A bar-tailed godwit standing in the grass.

Gill and colleagues propose that the reason why these birds travel along this transoceanic route because it may function as a safe corridor, providing a wind-assisted passage relatively free of hungry predators and harmful pathogens.

The amazing feat of the bar-tailed godwit leaves us with many new questions. How can the birds orientate while flying over the vast stretches of ocean? How do they manage to exert such high levels of exercise for such an amount of time? And how do they deal with dehydration and sleep deprivation? This is a good example again of how new scientific discoveries will often lead to even more unsolved questions. That’s the beauty of science.

Gill, R., Tibbitts, T., Douglas, D., Handel, C., Mulcahy, D., Gottschalck, J., Warnock, N., McCaffery, B., Battley, P., & Piersma, T. (2009). Extreme endurance flights by landbirds crossing the Pacific Ocean: ecological corridor rather than barrier? Proceedings of the Royal Society B: Biological Sciences, 276 (1656), 447-457 DOI: 10.1098/rspb.2008.1142

Hedenström, A. (2010). Extreme Endurance Migration: What Is the Limit to Non-Stop Flight? PLoS Biology, 8 (5) DOI: 10.1371/journal.pbio.1000362
  • Chris

    Very interesting read. Amazing they can fly such a distance without a break! Keep the articles coming!

    • http://mudfooted.com Jolle Jolles

      Dear Chris, Thanks for you nice comment, hope to see back again soon!

  • http://www.visionwalks.com wendy

    I’m seeing the Bar tailed Godwit at the moment on the Brunswick River, (near Byron Bay), Northern NSW, Australia

  • http://mudfooted.com Jolle

    Hi Wendy! Thanks for your comment and good to hear they safely arrived on the other side. Keep your eyes open for any ringed birds, it really helps conservationists if the public shares their sightings! If you have any nice photo’s of the godwits, I can add them to the post!

  • Shahidan Shafie

    A very interesting read indeed.
    From the Qur’anic perspective…translation of Verse 19, Chapter 67 (Surah Al Mulk): “Do they not observe the birds above them, spreading their wings and folding them in? None can uphold them except (Allah) most gracious: truly it is He that watches over all things.”

    The flight of birds is one of the most beautiful and wonderful things in nature. The make and arrangement of their feathers and bones, and their streamlined shapes, from beak to tail, are instances of purposive adaptation. They soar with outstretched wings; they dart about with folded wings; their motions upwards and downwards, as well as their stabilisation in the air, and when they rest on their feet, have given many ideas to man in the science and art of aeronautics. But who taught, or gave to birds the wonderful adaptations? None, but Allah, whose infinite mercy provides for every creature just those conditions which are best adapted for its life.

    [from page 1501: “The meaning of The Holy Qur’an,” by ‘Abdullah Yusuf Ali, 10th edition, Amana Publications, USA]