 The
Paridae is a family of homogeneous small birds, mostly resident in
forest
and woodlands around the globe. They are sprightly, clever birds full
of
character. I like this shot (left) of a Mountain Chickadee in
the
snows of eastern California, just taking off from a bare aspen. All
tits
and chickadees are agile, foraging by clinging to limbs, often upside
down.
Most of the English-speaking world call birds of the parid persuasion
"Tits,"
but in America we use the term "Chickadees" to avoid, I assume, the
giggling
double entrendre engendered by the juvenile American male's Playboy
obsessions. |
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 I
rather like all the tits for their curiosity and cleverness, but I
particularly
appreciate my local parid, the Chestnut-backed Chickadee
(right).
It is the focal species for foraging flocks of small songbirds, and a
key
species to locate when searching for vagrant warblers or vireos in the
fall. A good chunk of "eastern" vagrants that I've seen in Monterey
County
have been with these chickadee flocks. The same holds true for
Christmas
counts when the prizes are not necessarily vagrants, but scarce
wintering
western species, like Black-throated Gray Warbler. Again, one listens
for
the chickadees to find the flocks. As I often say on Christmas Bird
Counts:
"where there's chickadees, there's hope!"
Our local Audubon Society funded a Big Sur Ornithology Lab
(BSOL) study
of Chestnut-backed Chickadees. They caught and color-banded good
numbers
along the Big Sur River and followed them for several years, gaining
significant
insights into behaviors, survivorship, ecology, and movements. Each
year
a pair nests in or near my backyard. One summer they used a nest box
that
had been a Christmas gift, stuck to the fence right above our hot tub.
After the young had fledged we opened the box and found this perfect
3-inch
pad, composed mostly of strips of redwood back, that had cushioned the
eggs. It was immaculately clean — apparently tits are excellent
house-cleaners.
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The center of parid diversity is in east Asia, with 23
species (40%
of all tits) occurring there. There has been quite a bit taxonomic
uncertainty
about some of these, such as Songar Tit (below left) of China,
but
Dickinson (2003) splits it while Clements (1991) did not. Like a number
of recent splits, this decision relies heavily on vocalizations. A fair
number of Asian tits are crested, including Black-breasted Tit
(right)
of the western Himalayas. It is also an example of the current
instability
of English names around the world. When I took this photo over twenty
years
ago, the field guide I had used the lyrical name "Simla Black Tit."
Clements
(1991) uses the name "Black-breasted Tit" but Harrap & Quinn (1995)
use the much less descriptive "Rufous-naped Tit," and particularly non
useful when, like the photo, it is looking right at you!
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 The
species with the widest range and diversity is Great Tit
(right).
It is a very common species across wooded Eurasia, and has then
penetrated
Mediterranean islands, Middle East mountain ranges, and southeast Asia
islands and diverged into 33 named subspecies (Dickinson 2003). There
is
even a sight record of a vagrant from Little Diomede Island in the
Bering
Strait. This particular Great Tit, however, was captured at the Big Sur
River mouth in Monterey County, California. It appears to be of one of
the western European races and is an obvious escapee from captivity
[yes,
some people do keep tits as pets]. This bird set up shop along the
willow-lined
river and remained the entire summer in 2003.
There had been some disagreement about family status. Most authorities had classified parids as a distinctive family, but Sibley & Ahlquist (1990), based on preliminary DNA-DNA evidence, considered them a subfamily of a larger group that includes treecreepers and penduline tits. It is unfortunate that the recent family text (Harrap & Quinn 1995) followed this approach a bit too quickly. It should be considered preliminary and tentative. Instead, newer genetic work (e.g., Gill, Slikas & Sheldon 2005) shows that the Paridae are a unique lineage that arose in Asia. The ancestors of American titmice colonized the New World about 4 million years ago, and the ancestors of American chickadees followed about 3.5 million years ago. All parids feed primarily on insects, though they will take
fruit and
seeds when available. Many enjoy suet feeders. And all nest in cavities
in trees, roots, or (sometimes) stone walls. Many give a distinctive,
variably
nasal "chick-a-dee-dee-dee" call that is often heard in temperate
woodlands.
Some incorporate these notes within their territorial song while others
(like the Mountain Chickadee featured in the first photo) have an
entirely
different song — a mellow, whistled series recalling Zonotrichia
sparrows. [And I must mention that my rediscovery of nesting Mountain
Chickadees
near Cone Peak in 1991 (after their 30 year absence) was my personal
highlight
of the Monterey Breeding Bird Atlas project; see Roberson & Tenney
1993.]
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 The
'newest' member of the Paridae is Hume's Groundpecker (left and
below; it has recently been suggested it should be called Ground Tit).
It is a unique and puzzling passerine of the Tibetan and Qinghai
Plateau
of east-central Asia. It is a small, plain-colored bird: barely 20 cm
(7.8
inches) long, a little bigger and heavier (but shorter-tailed) than a
wagtail
and just a little smaller than a Sage Thrasher. It is very much a
terrestrial
species, living in grassy and stony habitats high on the Tibetan
plateau,
and moving about on long bounding hops, frequently flicking its tail
when
it stopped and flying only rarely. They dig actively for insects with
their
strong bill in turf, soil, and yak dung (Londei 2002, James et al.
2003).
This little-known species was described by Hume in 1871 with the generic name Podoces (which roughly translates "puzzling chough-thrush;" Londei 2002), along with another new species, Mongolian Ground-Jay Podoces hendersoni. The genus Podoces now consists of four species of ground-jays, the this species now placed in Pseudopodoces. Until the turn of the 21st century just a couple of years ago, Hume's Groundpecker was considered to be a corvid —thought to be related to ground-jays — and has gone by such names as "Hume's Ground-Jay" and "Tibetan Ground-Jay" (e.g., Sibley & Monroe 1990). It was thought to be the world's smallest jay. Doubt arose in the late 20th century as more was learned about this enigmatic bird. The rest of the ground-jays are fast runners, but the groundpecker has bounding hops. The rest of the ground-jays built stick nests (as, indeed, do virtually all of the corvids) while the groundpecker nests in holes. In fact, Hume's Groundpecker excavates a burrow in an earthen bank, often enlarging on rodent burrows or natural crevices, to place a nest of grass and moss inside. The photo (below) shows an adult groundpecker at the entrance to a nest at just about 12,000 foot elevation. You'll also note that the in the other photos on this page, the birds are carrying insects. During my brief visit to the Qinghai Plateau in June, all the adult groundpeckers were very actively foraging for insects on the ground and carrying them to active nests to feed the young inside. |
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 Borecky
(1978) was the first to raise doubts about the evolutionary
relationships
of Hume's Groundpecker, based on his comparative study of the
appendicular
muscles in the Corvidae. He recommended that future studies consider a
possible relationship with starlings (Sturnidae). Hope (1989) concurred
that Pseudopodoces was not a corvid, but based on her
comparative
study of osteology and phylogeny of the Corvidae, saw a possible
relationship
with nuthatches or tits based on the "distinctive upper jaw hinge."
James et al. (2003) studied the evolutionary relationships of Hume's Groundpecker using three data sets: comparative osteology, the nuclear c-myc gene, and mitochondrial DNA. All three sets of data agreed that this bird was not a jay, or a starling, but that it was actually a member of the Paridae (tits and chickadees). The mitochondrial DNA evidence suggested that its closest relative was Great Tit Parus major, and in their study James et al. (2003) embedded Pseudopodoces in the center of the genus Parus. They considered this assignment tentative, however, and refrained from merging the genus Pseudopodoces into the genus Parus. Dickinson (2003) was aware of the pending publication by James et al. (2003) but maintained this species within the Corvidae until the paper formally appeared. He did use, however, the new name Hume's Groundpecker. I was firmly persuaded by James et al. (2003) that the groundpecker evolved from a parid lineage but was skeptical of the finding of the close relationship with the genus Parus. Others had shown (e.g., Barker et al. 2004) that reliance on mitochondrial DNA alone can give incorrect results, and that sometimes taxa that have evolved long ago from a sister taxa, and are on a "long branch" in a phylogeny, are mistakenly assigned much closer relationships when only mtDNA is used. James et al. (2003) noted that while nuclear c-myc gene study supported the conclusion that Pseudopodoces was not a corvid, it did not show the close relationship with genus Parus as did the mtDNA evidence. It seemed to me that whether or not Pseudopodoces is "embedded" within Parus in the Paridae is still an open question. The degree of divergence shown (e.g., 8-11% from other Parus tits, but about 14% compared to nuthatches and starlings) might suggest that its evolutionary lineage is of long divergence from the Parus tits. For a short time in late 2004/early 2005, I elevated Hume's Groundpecker to family level status on this web site, but stated: "If further research confirms that it is the world's largest tit, and is closely related to the genus Parus, then this family status cannot stand." The much more extensive genetic evidence obtained by Gill, Slikas & Sheldon (2005) has answered my questions. They found the family Paridae to be monophyletic, with almost all the species belonging to the genus Parus, but with three distinctive monotypic genera: Sylviparus (Yellow-bellied Tit), Melanochlora (Sultan Tit), and Pseudopodoces (Ground Tit). This arrangement makes good, solid sense. Accordingly, I merge the groundpecker into the Paridae. It still is one unique bird . . . |
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| Photos: The Mountain ChickadeeParus
gambeli was photographed at Crowley Lake, Mono Co., California, on
19 Feb 1995. The Chestnut-backed Chickadee P.
rufescsens was in my backyard in Pacific Grove, Monterey Co.,
California,
on 14 Apr 2005. The
Songar Tit P.
songarus was at Wulingshan, Hebei, China, on 9 June 2004. The
Black-breasted
Tit P. rufonuchalus was at Pahalgam, Kashmir, India, on
16
Aug 1978. The captured
Great Tit P. major
was at BSOL, Monterey Co., California, 17 June 2003. The photos of
Hume's Groundpecker Pseudopodoces humilis were all taken
in Qinghai Province, China, in June 2004. The top shot was in the Caka
Valley, the bottom near Qinghai Lake, and the nest on Rubber Mountain
Pass.All
photos © 2005 Don Roberson; all rights reserved.
Bibliographic note Family book: Rating This is a pleasant and solid addition to the family books in the Princeton series. The plates appear separately in the front. I found the artwork rather good in a "field guide" style (without much background) opposite summary pages which include small maps. The maps I looked at were quite good (e.g., they and the text covered isolated populations of Mountain Chickadee in California, an unexpected bit of accuracy I've come to not expect in such family tomes). Distinct races are nicely covered, and they did well with the variation in my local chickadee, the Chestnut-backed. The text cover identification, habitat, breeding biology (very summarized), relationships, and detailed plumage descriptions, plus references which (in contrast to other similar efforts) look reasonably extensive. I don't personally see the need for the detailed plumage descriptions since no book like this can hope to cover the complete range of variation, and they are very tedious to read, but it is the "style" of these family books. There are some helpful extra maps and sketches of plumage details scattered in the text.Other literature cited: Barker, F.K., A. Cibois, P. Schikler, J. Feinstein, and J. Cracraft. 2004. Phylogeny and diversification of the largest avian radiation. Proc. Nat. Acad. Sci. 101: 11040-11045.TOP |
