The golden plover
Designed for energy conservation in flight
The animal kingdom contains many marvels that modern science has yet to fully explain. One example concerns the migration flight of the golden plover.
The Pacific golden plover (Pluvialis fulva) is a small shorebird, about the size of a dove. It lives from northern Siberia to western Alaska. Every year, these birds leave their young and fly south to spend the winter in South Asia, Southeast Asia, Australasia, or on various Pacific islands.1
Of the Alaska-dwelling members of this species, almost all (including those stopping en route to more distant destinations) make a migratory flight to Hawaii, where the bird is known as the kolea.2 Alaska to Hawaii means an 88-hour, non-stop flight across more than 4,500 km (2,800 miles) of open ocean. The birds are unable to swim, and there is no land between these locations for them to stop and rest.
Amazingly, for an individual plover to fly this distance would require more energy than is stored in its body.
Before departure, they put on additional weight, mostly in the form of fat reserves to sustain their long flight. On average, they gain enough to give each bird about 70 grams (2.4 oz) of consumable energy.3 Here is the dilemma, though; these birds in flight burn approximately 1 gram of energy per hour,4 so they should consume all their stored energy in about 70 hours, which is 18 hours short of Hawaii. However, each year the golden plovers make it to Hawaii. How is this possible?
As do some other kinds of birds, the plovers fly in a V-formation. This is so they can ‘draft’ off each other, which reduces the energy required to fly. This saves each bird, on average, 23% of the energy that would be used if flying unaccompanied. This is, however, not the case for the bird at the lead position, but the plovers take turns in that position and thus ‘share the load’.3 These golden plovers arrive in Hawaii every year with 6.8 g (0.24 oz), on average, left over from what they had ready for the flight. This provides insurance in case of non-advantageous winds encountered on the flight route.4
It is not uncommon for the plovers to lose 50% of their total body weight during this epic flight spanning less than four days. This is amazing. Imagine a 60 kg human losing 30 kg (65 lb) while jogging non-stop for this entire period, neither eating nor drinking—without any ill effects!
Sophisticated programming
The plovers’ innate abilities enabling them to perform this amazing migratory feat have all the hallmarks of design, engineered into their systems for migration purposes. Consider the following instinctive abilities, all of which are pre-programmed within the bird’s DNA, thus already in the fertilized egg:
- Timing their substantial fat gain. Each bird needs to have this extra fuel already on board when the time comes for them to depart, together, on their astonishing odyssey.
- Ensuring in advance the correct amount of fat for the distance needed. Too little, and the bird would plunge into the ocean and perish, its fuel all spent, before reaching its destination. Extra weight adds to the effort of flying this incredible distance, so with no possibility to rest, too much fat risks the bird again falling short of Hawaii, in this case from exhaustion.
- Drafting off each other in flight. Without such a clever aeronautic strategy, even the extra fat they carry would not last the distance. Consider, too, the built-in ingenuity that causes them to alternate the ‘lead pilot’ position, so that all of them share this energy-saving benefit equally.
Having laid and hatched their eggs, the parent plovers fly to Hawaii, leaving the younger plovers in Alaska on their own. They will eat, grow, and eventually attain their 70 grams of fat build-up before they depart for Hawaii somewhat later in the season. They make it to the same location, year after year.
How does this next generation know where to go without a map or an escort, with no guiding landmarks? And how does it ‘know’ in advance, to a high level of precision, how much fuel this super-long journey will need?
Migratory bird adaptation
In a recent study it was determined that some North American migratory birds are becoming smaller by 0.6% on average.1,2 Some scientists suggest that this is an adaptation to the current warming trend; smaller-bodied birds have a larger surface-area-to-volume ratio, so they can keep cool more easily. Interestingly, their wings aren’t shrinking, resulting in them having larger wings relative to their bodies. This is especially true for birds living at higher elevations, where the thinner air provides less lift.
- Youngflesh, C. and 3 others, Abiotic conditions shape spatial and temporal morphological variation in North American birds, Nature ecology & evolution 6(12):1860–1870, 2022.
- Nalewicki, J., Migratory birds in North America are shrinking as their wings get bigger. Climate change is to blame, livescience.com, 4 Nov 2022.
Tough questions for evolutionism
The systems underlying such avian achievements are very poorly understood, if at all. But what is clear is the level of sophistication such marvels exhibit. One can perhaps imagine natural selection fine-tuning aspects of these behaviours—so that the same systems can be modified to suit birds that subsequently fly on to Australia, for example. But that would require an underlying migratory mechanism of staggering complexity to be already in place. It is inconceivable that it would have arisen from random genetic accidents, as neo-Darwinian evolution requires. Any mutation driving a non-swimming bird to head off over vast stretches of ocean would be fatal if not accompanied by a host of other carefully synchronized changes to ensure the bird makes the distance.
A far more rational position is that all this reflects a Designer with intelligence and ability beyond all human understanding. In His omniscience He can say, “I know all the birds of the hills” (Psalm 50:11). This Designer, the Lord Jesus Christ, created all the original populations (kinds) of living things ex nihilo. He deserves our awe and praise:
O Lord, how manifold are your works! In wisdom have you made them all; the earth is full of your creatures (Psalm 104:24).
References and notes
- Stoddart, A., Identification—24-carat plovers. Learn to separate European, American and Pacific ‘Goldies’, Birdwatch Magazine, July 2017, reproduced on birdguides.com. The American golden plover, also found in Alaska, migrates to South America. Return to text.
- Field Guide to American Birds, Pacific Golden-Plover, audubon.org, acc. 30 Nov 2022. Return to text.
- Catchpoole, D., Wings on the wind: How do migrating birds know exactly when, and where, to go? Creation 23(4):16–23, 2001; creation.com/wings-on-the-wind. Return to text.
- Gitt, W., The flight of migratory birds, Acts and Facts 15(9), 1986; icr.org. Return to text.
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