The Woodpeckers are a large family of similarly designed birds found in
forested areas around the globe. The have specially evolved to deal with
chiseling wood, including "shock-absorber" head musculature, extremely
long tongues, and stiff tail feathers helping them perch upright on trees.
Woodpeckers are often a "core species" of the woodland avifauna [except
in two major areas that don't have any woodpeckers: Australasia and Madagascar].
There is almost nothing so pleasant on a lazy summer day in the red fir/lodgepole
pine forests of the Sierra Nevada as listening for the tapping of woodpeckers,
chasing each one done until a rare Black-backed Woodpecker (left)
is found, and then following it to its nest hole. This male, beautifully
photographed by Parker Backstrom, was delivering food to his brood.
Woodpeckers
come in a great variety of shapes and colors. One group are the flickers
which specialize in feeding on the ground, often focussing on ants. The
Campo
Flicker (right) of southern South America is such a species and a very
striking bird to boot. Yet even it has the stiffly pointed specialized
tail feathers that held woodpeckers perch vertically on tree trunks.
Another specialized group are the sapsuckers of North America. They
drill small holes into the cambium layer of living trees, causing sap to
ooze forth slowly. They do this on a set of favored (usually young) trees
and then follow their "trap line" from tree to tree, drinking the sap and
sometimes consuming insects attracted to it. Birch, aspen, willow &
orchard fruit trees are often favored, but they use some live oaks and
key into certain non-native trees (like pepper trees). In all, their regular
little square holes have been documented on over 250 species of native
trees. The juvenal-plumaged Yellow-breasted Sapsucker (below) is
sitting cryptically near an oft-drilled tree; this particular individual
was a rare vagrant to coastal California (and documented by this fine Jeff
N. Davis photo).
I call woodpeckers "core species" because their presence is a fundamental
requirement to the existence of a wide range of other birds. Woodpeckers
drill new nest holes each year, and thus many old nest cavities are available
for a entire suite of hole-nesting species. Large species like the Northern
Flicker (below) are particularly important for cavity-nesting holes
and, in western North America, Purple Martins.
Many smaller species of North American swallow are dependent on woodpecker
holes, as are virtually all the small owls, various bluebirds, and a huge
array of small birds (wrens, chickadees) that use them advantageously.
Some of the much interesting woodpeckers from a research standpoint are in the widespread New World genus Melanerpes (22 species). My favorite, and the best studied, is the Acorn Woodpecker (below left). It breeds cooperatively in communal groups featuring one or two lead males, a harem of females (mostly sisters), and youngsters from the previous year, one of the most unusual breeding systems in the natural world. Much of the research has occurred in the oak woodlands of Monterey County, California (where I live), and some fascinating facts are in MacRoberts & MacRoberts (1976), Koenig (1981), Koenig & Mumme (1987), and Stacey & Koenig (1984). Acorn Woodpeckers also collect and store acorns in "granary trees" against lean times. They are also frequent at my bird feeder, eating ordinary bird seed in times when acorn crops are poor. Another colorful Melanerpes is the Hispaniola Woodpecker (below right) which is endemic to that single large Caribbean island.
At over two hundred species around the world, there is tremendous diversity among the woodpeckers. The two wrynecks of the Old World are included within the family, and there are well over two dozen species of tiny piculets in the world's tropics. There are also huge forest-dominating species in the several genera, including the genera Dryocopus and Campephilus.
These powerful birds, including the White-bellied Woodpecker (far
left) of southern Asia, and the Crimson-crested Woodpecker (near
left) of the Neotropics, are always prized by birders. My shots here are
not much, but experiencing a huge, crested and colorful woodpecker deep
in virgin jungle is always a memorable experience. Among the huge woodpeckers
nine species of extant Campephilus in the New World, four species
of flameback (Dinopium) in southeast Asia, and two Mulleripicus
from the Philippines (Sooty & Great Slaty woodpeckers) are particularly
impressive.
Alas, two the world's most awesome woodpeckers have apparently become extinct within my lifetime. The Ivory-billed Woodpecker Campephilus principalis of the southeastern U.S. and Cuba was always scarce, but loss of sufficient tracts of wild habitat doomed it by World War II. The last ones were likely in the 1960s, maybe early '70s. The Imperial Woodpecker C. imperialis of virgin pine forests in the Sierra Madre of nw. Mexico was even larger, and has not have been confirmed since 1957. Like all mythical creatures (e.g., Bigfoot, the Yeti ="Abominable Snowman", the Loch Ness Monster), rumors of their existence continue to circulate (in the case of the Ivory-billed there was a major rumor as recently as 1999, but with as little substance as the usual reports of UFOs). It appears these two great birds have been lost forever.
Photos: The adult male Black-backed Woodpecker Picoides arcticus was feeding young near Shaver Lake, Fresno, California, on 11 June 1989, where Parker Backstrom took this fine shot. The Campo Flicker Colaptes campestris was feeding on the ground in the Brazilian Pantanal in Aug 1999. The juvenal Yellow-bellied Sapsucker Sphyrapicus varius was a vagrant to Andrew Molera State Park, Monterey Co., California, on 23 Oct 1993; photo by Jeff N. Davis. The female Northern Flicker Colaptes auratus was coming out of her nest hole in Sacramento, California, in April 1980. The male Acorn Woodpecker Melanerpes formicivorus was on its way to the feeder in my backyard in Pacific Grove, California, on 6 June 1999. The Hispaniola Woodpecker Melanerpes striatus was foraging for grubs in this old trunk at the arboretum in Santo Domingo, Dominican Republic, in Jan 1999. The White-bellied Woodpecker Dryocopus javensis was on Palawan I., the Philippines, in Feb 1990. The Crimson-crested Woodpecker Campephilus melanoleucos was in s.e. Peru in June 1987. Photos © 2000 Don Roberson, except those by Parker Backstrom and Jeff N. Davis, who hold those copyrights (used with permission), all rights reserved.
Bibliographic note
Family book: Rating HHHI [= 3 1/2
out of 5 possible]
Short, Lester. 1982. Woodpeckers of the World. Delaware Mus. Nat. Hist.,
Monogr. Ser. 4.
Family book: Rating HHHI [= 3 1/2
out of 5 possible]
Winkler, Hans, David A. Christie, and David Nurney. 1995. Woodpeckers:
An Identification Guide to the Woodpeckers of the World. Houghton Mifflin,
Boston, MA.
These two major family books represent their decades well. Short's 1982 was a true monograph, based heavily on his one research and incredibly detailed in its discussion of behavior, vocalizations, and interactions with other birds. It is a thick 676 pages. Color plates of all species (by George Sandström) are bound together in back; there are no range maps (but details of distribution are set out at length in the text. Taxonomy was one of Short's primary interests, so there is much here on this topic.
The Winkler/Christie book (Nurney was the artist) is a standard "cookie-cutter" family book, much like the Pica Press series (although this one is by Houghton Mifflin, so better in some ways), with color plates facing a short i.d. text bound together in the front, and then detailed species accounts with range maps. The introductory chapters are much shorter than in true monographs, but at 406 pages this is a heftier effort than many other family books in this format.
Neither has particularly outstanding art. In Short's tome several species (sometimes from different continents) are shown together on a single branch in a variety of positions; Nurney's art in the newer book is "field guide" style, with all birds on each plate facing the same way in the same posture. The latter layout is better for comparing difficult species to each other, but neither format strikes any evocative note, and I knock off one star from each book for underwhelming art.
The differences in decades is apparent in the number of species covered, although the exact same set of birds is at issue. Short, writing at a time when "lumpers" were in the ascendancy, lists 198 species. Winkler/Christie list 214 species and, as one would expect, spend some time talking about the new taxonomic proposals of Sibley & Ahlquist (1990). [I also use 214 species, taken from Clements (1991), but delete two extinct birds from that list and add two recent splits.]
One wants a family book to have an outstanding bibliography for the group, and the Winkler/Christie effort looks better in this regard. Of course, they cite "Short (1982)" as the primary, seminal source for much of their work. One must consult the Short book for any questions of taxonomy (Winkler/Christie follow Short closely on subspecies decisions), and for any question of vocalization or behavior. The clear range maps in Winkler/Christie even up their deficiencies on Short's strong topics. It does appear to me that Short will be more authoritative on New World topics (he is an American and knows North American woodpeckers particularly well), while Winkler/Christie are comparatively weak on New World species (I think all the authors and the artist are British), but presumably would be stronger on Old World topics, particularly those in the Western Palearctic.
One disappointment about both books is their failure to address the finer points of identification. Neither gets much beyond the "field guide" stage of i.d. (although Short is very strong on subspecific variation). For example, here in Monterey County we occasional get claims by visiting birders of a male "Black-backed Woodpecker" in our mountains. Such a claim is presumed erroneous, and certainly all those from the summer (when such claims have been made), since the Sierra Nevada population just doesn't move enough to send vagrants across the treeless Central and Salinas valleys to the Santa Lucia Mountains. The details are always much too insubstantial -- a woodpecker with an orange or yellow forehead, a striped face, and an "all-black" back. [Never any critical details about the fine details of facial pattern, or the presence/absence of flank barring, or details of tail or covert patterns.] Such birds are not "Black-backed Woodpeckers." But what are they?
Since they are always reported in late summer, when juvenal Hairy Woodpeckers are fledged and obvious, I assume all reports are juvenal Hairies. Such birds do have yellow or orange forecrowns, accounting for that point not shown in the birder's field guide, and one could learn that character of Hairy juvenal plumage in either Short or Winkler/Christie. But what of the "all-black" back? Both books discuss variation in Hairy (especially birds from Newfoundland) that have essentially black backs -- but certainly a Newfoundland Hairy Woodpecker is not in Monterey's mountains in summer. I think the answer is in Short (1969) which details (with photos) a melanistic Hairy Woodpecker from New Mexico, or a black-backed bird in otherwise prominently white-backed populations. This rare aberration could account for the once-in-a-decade claim of "black-backed" woodpeckers in Monterey, which are melanistic juvenal Hairy Woodpeckers. But you couldn't find this out in either of the family book under discussion. Winkler/Christie don't discuss this i.d. problem (although there is a "similar species" category for every bird) and don't cite Short's paper anywhere. Even more strange, Short (1982) doesn't cite his own paper anywhere either! [He cites numerous other publications by him, but not this one.] The only i.d. text that includes this discussion is in Trochet et al. (1988), yet another obscure paper [and one not mentioned by Winkler/Christie].
And while we're on the topic of bibliography and research, why doesn't either book cite Remsen et al. (1976) when Ringed Woodpecker of South America is discussed? Sure it wasn't anything earth-shattering, but very little has been published about Ringed Woodpecker; there are brief behavior notes in the short text (the first one in a formal ornithological journal that included my name as an author!), and I would want an authoritative family text to include everything published of this sort. Finally, both books are weak on vagrancy. Neither, for example, mention vagrant Red-headed Woodpeckers in California (although Short does mention that western populations are "highly migratory.") So, even despite the rather "out-in-left-field" discussion in these concluding paragraphs, I end up being disappointed in both books. They are, actually, both rather fine publications but I can't bring myself to give either of them better than a 3.5 score (out of 5 possible).
Literature cited:
Clements, J. F. 1991. Birds of the World: A Checklist. 4th ed. Ibis Publ., Vista, CA.TOPKoenig, W. D. 1981. Reproductive success, group size, and the evolution of cooperative breeding in the Acorn Woodpecker. Amer. Naturalist 117:421-443.
Koenig, W. D., and R. L. Mumme. 1987. Population ecology of the cooperatively breeding Acorn Woodpecker. Monographs in Population Biology 24. Princeton Univ., Princeton, N. J.
MacRoberts, M. H., and B. R. MacRoberts. 1976. Social organization and behavior of the Acorn Woodpecker in central coastal California. Ornithol. Monographs 21.
Remsen, J. V., Jr., J. S. Luther, and D. Roberson. 1976. A Ringed Woodpecker Celeus torquatus in Colombia. Bull. Brit. Ornith. Club 96: 40.
Short, L. 1969. An apparently melanistic Hairy Woodpecker from New Mexico. Bird-Banding 40: 145-146.
Sibley, C. G., and J. E. Alquist. 1990. Phylogeny and Classification of Birds: A Study in Molecular Evolution. Yale Univ. Press, New Haven, CT.
Stacey, P. B., and W. D. Koenig. 1984. Cooperative breeding in the Acorn Woodpecker. Scientific America 251: 114-121.
Trochet, J., J. Morlan, and D. Roberson. 1988. First record of the Three-toed Woodpecker in California. W. Birds 19: 109-115.
