Why Egg-producing Woodpeckers Snack on Bones

Dr. James J. S. Johnson

To everything there is a season, and a time to every purpose under the heaven.  (Ecclesiastes 3:1)

KONICA MINOLTA DIGITAL CAMERA

RED-COCKADED WOODPECKER (Carolina Bird Club photo)

Woodpeckers are famous for eating insects—beetles, caterpillars, “grubs” (insect larvae), spiders, ants, etc.—as well as occasionally eating berries and other fruits.  But what about vitamins and minerals, how do woodpeckers get what they need? 

Consider this:  when you eat eggs—boiled, poached, or as omelets—do you discard the eggshells? Likewise, if you eat trout or turkey, do you recycle your fish or fowl bones?

Some birds and mammals eat broken eggshells or snail shells to get nutritionally valuable calcium.[1]  Also, some birds—such as Red-cockaded woodpeckers[2] and Alaskan sandpipers[3]—munch on bones, to get calcium, especially during breeding season.

Getting calcium (usually from calcium carbonate: CaCO3) is needful, of course, but how do birds know they need calcium, especially during the breeding season? 

A related question: how do expectant human mothers, who suddenly crave finfish or shellfish (or pickles, or Buffalo hot wings, or whatever) know that they need a nutritional change, while their physiologically transformed womb-factories busily build beautiful babies? 

God somehow provides an urge to eat certain foods that we need, when we need those foods—this is something we gained by so-called evolutionary “luck” or random “chance”!  In fact, successful reproduction of populations, whether they be human or animal, is something that is unfixable if reproduction is ever broken. (In other words, true extinction is forever—there are no second chances!)

Actually, calcium nutrition-satisfying behavior makes sense, biblically, because it helps Christ’s creatures to reproduce successfully, i.e., to “be fruitful and multiply”, so their kinds can “fill” (populate) Earth’s habitats. Thus, learning how creatures fulfill the Genesis Mandate helps us to “cast down” haughty imaginations (2nd Corinthians 10:4-5), such as the imaginations of Darwinists, who try to replace Christ with animistic “nature-creating-itself” mythology, masquerading falsely as “science” (1st Timothy 6:20)–as if inanimate “nature” could somehow “select” helpful results for promoting life on Earth!

During Creation Week (on Day #5, to be exact), the Lord Jesus Christ (as Creator[4]) commanded birds to reproduce (and “fill” environments); He also equipped them with what they need, to do so.  Many of the intricate details we are just now learning. 

Further complicating matters, successful reproduction requires a harmony of physical traits (biochemically regulated by genetics/epigenetics) with decision-based behaviors (which rely upon learning, by the non-physical “soul” of a bird).  The details of successfully blending physical body systems, with non-physical learned behaviors, is one of the “wonders without number” (Job 9:10) that we can admire God for, as we reverently study how God’s creatures live.[5] 

Of course, when creatures purposefully search local habitats for needed nutrients—including vital minerals like calcium—they exhibit continuous environmental tracking (CET), as they hunt and select what they need from their territory.  Thus, Christ equipped animals to actively select what they need, from their habitats—it is not true that habitats “select” or “shape” passive animals.[6]

So, what can we learn from our Lord Jesus Christ’s red-cockaded woodpeckers (Picoides borealis), that recycle calcium from collected bone fragments, consuming bone flakes just before and when they are laying eggs?

The females took bone fragments from raptor pellets located on the ground. … Small bone fragments were consumed at the pellets whereas larger pieces were taken to a tree trunk (by flight) where they were pecked and mandibulated. … Pieces of bone were cached by placing them between scales of [tree-trunk] bark and then hammering them with the bill until they were wedged. We confirmed that bones were cached by recovering two pieces of bone from trees and by observing birds recover cached bones, handle them and cache them elsewhere.2

Repasky, Blue, & Doerr article cited in endnote 2 (below)

Selecting and ingesting bone-pecked calcium is targeted and purposeful—not random—because mother woodpeckers seek and extract calcium from bone fragments during breeding seasons (hiding bone fragments for later “snacks”), mostly ignoring those bones when they cease producing eggs2,4,5—amazing! 

Darwinian trial-and-error “luck” cannot explain how these wise woodpeckers know to hunt and ingest calcium-rich bone flakes, timed to egg-producing seasons.4,5  However, the Lord Jesus Christ is the Mastermind of purposeful timing for all of His creation (Ecclesiastes 3:1), including female red-cockaded woodpeckers.

RED-COCKADED WOODPECKERS (James Audubon watercolor — public domain)

REFERENCES



[1] E.g., Mary Straus, “Calcium in Homemade Dog Food”, WHOLE DOG JOURNAL (May 28, 2019), at http://www.whole-dog-journal.com/food/calcium-in-homemade-dog-food/ (calcium from eggshells). See also Samuel L. Beasom & Oliver H. Pattee, “Utilization of Snails by Rio Grande Turkey Hens”, JOURNAL OF WILDLIFE MANAGEMENT, 42:916-919 (1978). 

[2] Richard R. Repasky, Roberta J. Blue, & Philip D. Doerr, “Laying Red-cockaded Woodpeckers Cache Bone Fragments”, THE CONDOR, 93(2):458-461 (1991).  Red-cockaded woodpeckers resemble 4 other American woodpeckers, the Ladder-backed Woodpecker, Downy Woodpecker, Hairy Woodpecker, and Nuttall’s Woodpecker.  It appears that Red-cockaded Woodpeckers can hybridize with Hairy Woodpeckers (Picoides villosus), which in turn hybridize with Ladder-backed Woodpeckers (Picoides scalaris), which hybridize with Downy Woodpeckers (Picoides pubescens) and with Nuttall’s Woodpecker (Picoides nuttallii). See Eugene M. McCarty, HANDBOOK OF AVIAN HYBRIDS OF THE WORLD (New York, NY: Oxford University Press, 2006), pages 107-108.

[3] Stephen F. MacLean, Jr., “Lemming Bones as a Source of Calcium for Arctic Sandpipers (Calidris spp.)”, IBIS (INTERNATIONAL JOURNAL OF AVIAN SCIENCE), 116:552-557 (1974).

[4] See John 1:1-10 & Colossians 1:16-17 & Hebrews 1:1-2, etc. 

[5] “Although qualitatively distinct from humans—who are made in God’s image (Genesis 1:27)—animals have what Scripture calls a “soul” (Hebrew nephesh). … But the resourcefulness of animals should not surprise us. Proverbs [30:24-28] informs us that God wisely installed wisdom into animals—even small creatures like ants, conies, locusts, and lizards.  Literally, these animals are “wise from receiving [God’s] wisdom.”7 Fascinating!” Quoting James J. S. Johnson, “Clever Creatures: ‘Wise from Receiving Wisdom’”, ACTS & FACTS, 46(3):21 (March 2017). 

[6] Randy J. Guliuzza, “A New Commitment to Deep Research”, ACTS & FACTS, 50(9):4-5 (September 2021).

RED-COCKADED WOODPECKER (Carolina Bird Club photo)

Hagerman NWR:  Missing the Northern Shovelers (and Other Winter Migrants)

Hagerman NWR:  Missing the Northern Shovelers and Other Winter Migrants

Dr. James J. S. Johnson

To everything there is a season, and a time to every purpose under the heaven.

Ecclesiastes 3:1
NORTHERN SHOVELER pair   (Wikipedia photo credit)

Recently I visited Hagerman National Wildlife Refuge (near Sherman, Texas — bordering Lake Texoma), hoping to see a lot of migratory birds, especially geese and ducks who visit wetlands for overwintering or for quick stopovers.  Compared to prior visits, it was a major disappointment.  Even the visitors center was locked, closed to visitors (with a posted sign claiming pandemic dangers as the excuse for the closure).

Possibly due to a year of drought, many of the large ponds were shrunken (leaving half-dried mud basins), demonstrating that water is the key ingredient for wetland habitats.  The winter wheat was mostly consumed, so the population of snow geese was minimal.  Dozens and scores of snow geese could be seen, but not the usual hundreds or thousands. An occasional Great Blue Heron could be seen. Meanwhile the oil pumps (“horseheads”) quietly pumped. Even the few ducks seemed bored.

The Northern Pintail ducks were few and far between.  And, worse, I saw no Northern Shoveler ducks at all. Likewise, I don’t recall seeing the usual Green-winged Teals. Those shallow drought-dried wetlands must have been unattractive to most of the avian winter visitors, such as migratory ducks and geese. 

HAGERMAN NATIONAL WILDLIFE REFUGE, near Sherman, Texas (10,000 Birds photo credit)

So maybe this limerick can express my birding disappointment, that day, at Hagerman NWR:

DROUGHTS DISAPPOINT BIRDWATCHING AT WINTER WETLANDS

Hagerman’s a refuge of peace,

Fit for migrating ducks and geese;

Yet no shovelers were seen,

Nor teals with wings green —

Just some pintails, and a few geese.

[JJSJ, AD2022-01-19]

Oh well, goodbye — maybe next winter will be better, for viewing winter migrants at Hagerman NWR.

NORTHERN SHOVELER male in freshwater   (Steve Sinclair photo credit)