Chapter C: W. and J. H. Bowles (1906) write of its haunts in Washington

Like the hermit warbler, a bird of the higher altitudes in the mountains of California, the Calaveras warbler, on reaching the cooler climate of the northwest, is to be found as a rule only on the driest prairies. Here the birds frequent the scattered clumps of young oaks and fir trees that have reached a height of some three or four feet, and which border the large tracts of dense fir timber. It is a noteworthy fact that, while these birds are not often to be found more than a hundred yards outside of the forests, they are seldom or never seen inside of the dividing line where the heavy timber meets the prairie. Also they do not encroach upon the hillside territory of the lutescent warbler, which bird in turn does not appear on the prairies but confines itself to the brush-covered uplands.

_Nesting._--Dr. Osgood (1896) found three nests of the western Nashville, or Calaveras, warbler near Fyffe in the Sierras; two of these were concealed under dead leaves, one of which was partially concealed by a little sprig of cedar at the foot of a cedar stump, and the other was under a little tuft of "mountain misery"; the third was in a thick patch of "mountain misery" and was "well embedded among the roots of this little shrub, and shaded by its thick leaves."

In the Yosemite Valley, Grinnell and Storer (1924) found a nest in what must be an unusual situation:

The location was only about 75 feet from the much traveled south road on the Valley floor and at the base of the talus pile of huge boulders. The nest was in the face of one of the larger of these boulders, partly in a diagonal fissure. It was on the north side of the rock and so never received any direct rays of sunlight. The whole face of the boulder was covered densely with yellow-green moss which in places was overlaid by olive-gray lichens. The nest was 43 inches from the base of the rock and about 60 inches from the top. Another nest was found in a hollow of the ground at the base of an azalea bush, near an old road along the hillside. The creek itself was about 50 feet distant. This nest was 3 inches across the outside and about 2 inches high, the cavity being 1-1/4 inches deep. Strips of bark of the incense cedar, plant fibers, and horsehair comprised the building material.

The Bowles brothers (1906) say that the nests are very much like those of the eastern Nashville warbler, as taken by them in Massachusetts. In Washington, "the site chosen is usually at the base of a very young oak, or fir, tho on one occasion we found one built under some blackberry vines at the base of a large fir stub. The nests are sunk well into the ground or moss, and are so well concealed as to defy discovery unless one flushes the bird."

_Eggs._--The eggs of the western Nashville warbler are practically indistinguishable from those of the eastern form. The measurements of 40 eggs average 15.3 by 12.2 millimeters; the eggs showing the four extremes measure =16.6= by =13.2=, =14.3= by 11.9, and 16.0 by =11.5= millimeters (Harris).

We have no information on the incubation of the eggs or care of the young. The changes in plumage parallel those of the eastern bird. Very little seems to be known about the exact food of the Calaveras warbler, and its voice seems to be the same as that of the Nashville, but the following accounts of its habits seem worth quoting. Grinnell and Storer (1924) write:

The forage range of this warbler lies chiefly in trees other than conifers. Such trees as the black oak and big-leafed maple renew their foliage every spring and the Calaveras Warblers find excellent forage in the insects and larvae which feed upon this tender new leafage during the spring and summer months. Less often these birds may be found in golden oaks and occasionally in Douglas spruces. They usually forage 25 to 40 feet above the ground, keeping within the stratum of new foliage, but they have been seen as low as 10 feet and as high as 70 feet above the earth. When within the foliage their yellow and green coloration makes it difficult to locate them, especially as the birds do not move about as rapidly as some of the other warblers. At times a Calaveras Warbler will poise on rapidly beating wings to capture some insect otherwise out of reach.

Dr. J. C. Merrill (1888) calls them "restless, shy, and very difficult to shoot", and says further, "When alarmed, as they very easily are, the males move rapidly through the trees, often flying a hundred yards or more at once, and were it not that their constant song indicates their movements, it would be impossible to follow them. I have frequently followed one for half an hour or more before I could even catch a glimpse of it, and my pursuit of any particular one was more often unsuccessful than the reverse. * * * I have never found a land bird more wary and difficult to shoot. But as soon as the young leave the nest this extreme shyness disappears, and the parents are readily approached and observed as they busily search for food for their young family."

Dr. William T. Shaw, who collected a specimen of this warbler in northwestern Washington, says in his notes: "This warbler, a singing male, was noticeably a percher upon high, isolated cedar poles when singing, having three or four favorite ones in his territory, which was a hillside grown to a height of about 15 feet with second-growth deciduous trees, following fire. He sang from a height of from 30 to 40 feet up near the top of these old widely-scattered, fire-blasted, weather-bleached trees, clearly out in the open and isolated from green sheltering foliage beneath him, in such a location as one is accustomed to seeing lazuli buntings perch when they sing." Dr. Shaw thought the first part of the song suggested that of Macgillivray's warbler, and the latter notes reminded him of "those heard among the inspirational notes in the song of the lazuli bunting."

The Bowles brothers (1906) say that, in the spring, the males have at times a very pleasing habit while singing, "that of hovering thru the air for a distance of fifteen or twenty yards. The manner of flying at these times is very slow and closely resembles that of one of the marsh wrens, but the beak is turned upwards and the feathers on the swelling throat separate until it seems almost certain that the bird will sing himself into some serious bodily mishap."

VERMIVORA VIRGINIAE (Baird)

VIRGINIA'S WARBLER

PLATE 18

HABITS

This warbler was discovered by Dr. W. W. Anderson, at Fort Burgwyn, New Mexico, and was described by Baird, in a footnote in The Birds of North America, by Baird, Cassin, and Lawrence (1860). The footnote occurs under the explanation of plates in the second volume. The warbler was named for Mrs. Virginia Anderson, wife of the discoverer.

Its range during the breeding season covers portions of Nevada, Utah, Colorado, Arizona, and New Mexico, mainly in the mountain regions, and it retires to Mexico for the winter. It seems to be more abundant in Colorado than elsewhere, breeding from the foothills, where it is a characteristic bird and perhaps the most abundant of the wood warblers, up to 7,500 to 8,000 feet in the mountains. On the spring migration, it is abundant along the valley streams, among the cottonwoods and willows, or sometimes among the pines; but in the summer it is found among the low scrub oak brush on the hillsides.

Bailey and Niedrach (1938) write attractively of Virginia's warbler in its Colorado haunts:

In the broken prairie where the yellow pines have taken their stand upon the crest of the tableland, and in the rocky canyons clothed with the scraggly scrub oaks slipping down to narrow grass-grown creek-bottoms, Virginia's Warbler chooses its nesting grounds.

Plants seem to burst into life during the early weeks in May. * * * The flowers of the scrub oaks tinge the hillsides with a greenish-yellow bloom; the green of bursting leaves and grasses soon blends with the nodding blossoms of the pasque-flower; the beautiful pink plume sways on the hillside, and yellow blossoms of the Oregon grape thrust forth among the holly-like leaves, making one think of flowering Christmas wreaths. It is then that the Virginia's Warblers are at the height of their activity. Their colors are the grays and yellows of the new vegetation. The males perch among scrub-oak branches and yellow pines, where they are usually concealed, and do their utmost to outsing their towhee neighbors.

In Nevada, Ridgway (1877) first observed this warbler "among the cedar and piñon groves on the eastern slope of the Ruby Mountains. * * * On the Wasatch and Uintah Mountains it was more abundant, being particularly plentiful among the scrub-oaks on the foothills near Salt Lake City. They lived entirely among the bushes, which there were so dense that the birds were difficult to obtain, even when shot."

In the Charleston Mountains, Nev., according to A. J. van Rossem (1936), "the distribution appeared to be limited to the so-called Upper Sonoran associations of mahogany and Gambel oaks, and therefore the species is considered characteristic of that zone, although the extremes of altitude at which it was found were 6,300 and 9,000 feet. Because of the relative scarcity of oaks, by far the greater number were found in mahogany which here grows as low, dense forest, instead of in the more familiar shrub form in which it is usually known."

In the Great Basin region, Dr. Jean M. Linsdale (1938) found Virginia's warblers in a variety of situations, such as "in sage on rocky, piñon-covered slope 100 yards from a stream; in sage on top of ridge; at tip of mountain mahogany tree; in plum thicket; singing and foraging through upper foliage of tall birches close to creek; in cottonwoods and piñons close to creeks; singing in dead shrub 10 feet high at base of rock slide; in aspen; in thickets of sage, elder, _Ephedra_, and _Symphoricarpos_; in willow; on ground among rocks at crest of ridge." The altitudes ranged from 6,500 to 8,000 feet, with the largest number between 7,000 and 7,500 feet.

In southern Arizona, this warbler, according to Mr. Swarth (1904)--

proved to be very abundant during the spring migration, particularly in the lower parts of the mountains; but the most of them seem to go farther north, and but few, compared with the numbers seen in April and the early part of May, remained through the summer to breed. The earliest arrival noted was on April 10th and soon after they were quite abundant, mostly in the oak region below 5000 feet, remaining so throughout April and up to the first week in May, at which time the migrating birds had about all passed on. All that were seen after that I took to be breeding birds, for they gradually moved to a higher altitude, (6000 to 8000 feet) and were nearly all in pairs. About the middle of April, 1902, I found a few _virginiae_, together with other migrating warblers, in the willows along the San Pedro River, some fifteen miles from the mountains.

_Nesting._--Ridgway was evidently the first to record the nest of Virginia's warbler, finding it near Salt Lake City on June 9, 1869. "The nest was embedded in the deposits of dead or decaying leaves, on ground covered by dense oak-brush. Its rim was just even with the surface. It was built on the side of a narrow ravine at the bottom of which was a small stream. The nest itself is two inches in depth by three and a half in diameter. It consists of a loose but intricate interweaving of fine strips of the inner bark of the mountain mahogany, fine stems of grasses, roots, and mosses, and is lined with the same with the addition of the fur and hair of the smaller animals" (Baird, Brewer, and Ridgway, 1874).

Shortly afterwards, a nest was found on June 1, 1873, in Colorado, by C. E. Aiken. It was reported by Aiken and Warren (1914) as "the first nest of this species known to science. * * * This was sunk in the ground in a tuft of bunch grass growing in a clump of oak brush, with the dead grass hanging over and completely concealing the nest, which was reached through a small round hole like a mouse hole through the protecting grass."

Dr. Linsdale (1938) reports a nest found in Nevada, at an elevation of 7,700 feet, that "was at the lower edge of a clump of grass 20 inches tall and 2 feet across. The surrounding hillside was of small rocks lying at a maximum angle of rest. A few similar grass clumps were scattered near, about 10 feet apart. The surrounding trees were mountain mahogany and chokecherry. The nest was composed entirely of grass and was in a depression in the loose soil. It was well concealed by dead grass at the base of the tuft."

In the Huachuca Mountains, Ariz., Mr. Swarth (1904) found a nest that "was built on a steep sidehill about ten feet from a much traveled trail, and was very well concealed; being under a thick bunch of overhanging grass, and sunk into the ground besides, so as to be entirely hid from view. This was at an elevation of about 8,000 feet, which seems to be about the upward limit for this species in this region."

We found Virginia's warbler fairly common there in the middle reaches of the canyons, around 7,000 feet, and found a nest being built at the base of a bush of mountain misery; Mr. Willard collected it with a set of three eggs on June 4, 1922; it was made of leaves and strips of bark and was lined with horsehair.

Another nest before me, from the Huachucas, has a foundation of moss and lichens, dry leaves, and strips of cedar bark, over which are finer strips of the bark and shreds of dry weed stalks and grasses, with a lining of still finer fibers; it is a shallow nest, its diameter being 3 by 3-1/2 inches outside and 2 inches inside.

_Eggs._--While 4 eggs seem to constitute the usual set for Virginia's warbler, as few as 3 and as many as 5 have been reported. These are ovate to short ovate and only slightly lustrous. They are white, finely speckled or spotted with shades of reddish brown, such as "chestnut" and "auburn," intermingled with faint specks of "pale vinaceous-drab." Some eggs are profusely spotted over the entire surface, while others have the markings concentrated at the large end. The measurements of 40 eggs average 15.9 by 12.4 millimeters; the eggs showing the four extremes measure =17.0= by 12.4, 16.0 by =13.0=, =14.2= by 12.2, and 16.3 by =11.2= millimeters (Harris).

_Young._--On the period of incubation and on the development and care of the young we have no information except the following observations of Bailey and Niedrach (1938): "The hatching time of many species of Colorado birds seems to coincide with an abundance of larvae feeding upon plants among which the birds are nesting. We have noticed time and again, that pests are numerous upon the vegetation when the fledglings are in the nest, but a few weeks later, after the little fellows have taken wing and are able to move to other parts, the caterpillars have gone into the pupa stage." At a nest they were watching, they observed that both parents shared the work of feeding the young, averaging a trip every 6 minutes.

A. J. van Rossem (1936) took young birds that were not fully grown on July 10, and others on July 13 that had nearly completed the postjuvenal molt, from which he inferred that two broods might be raised in a season. H. S. Swarth (1904) noted that the young birds began to appear in the Huachuca Mountains about the middle of July, after which both old and young birds moved down into the foothills.

_Plumages._--The young Virginia's warbler in juvenal plumage is plain grayish brown above; the throat, chest, and sides are paler brownish gray; the abdomen and center of the breast white; the upper and under tail coverts are dull greenish yellow; there is no chestnut crown patch; and the greater and median wing coverts are tipped with dull buffy. The sexes are alike.

The postjuvenal molt begins early in July and is often complete before the end of that month. The first winter plumage is similar to that of the adult female at that season. In this plumage the sexes are not very different, and the crown patch is not much in evidence or is altogether lacking in the young female; both sexes are browner and with less yellow than in the adult plumage, and the female is duller than the male.

A partial prenuptial molt occurs between February and May, mainly about the head, during which the chestnut crown patch is at least partially assumed and the young birds become almost indistinguishable from adults. There is, however, considerable individual variation in the advance toward maturity.

Subsequent molts consist of a complete postnuptial molt in July and August, and a partial prenuptial molt in early spring. The adult male in the fall is browner above and on the flanks, and the yellow on the chest is duller than in the spring, while the chestnut crown patch is concealed by brownish gray tips. The female, also, is browner than in the spring, with little if any yellow on the chest and with the crown patch similarly concealed. In spring birds there is much individual variation, perhaps owing to age, in the amount of yellow on the breast, throat, and chin. Some females are nearly as brightly colored as are the duller males, some have very little yellow on the chest and some lack the chestnut crown patch.

_Food._--Our information on the food of Virginia's warbler is limited to the observation of Bailey and Niedrach (1938) who saw a pair of these warblers feeding their young on the caterpillars that eat the foliage of the trees and shrubs on their nesting grounds. It is significant that after these caterpillars are no longer available the warbler leaves its breeding haunts and moves down into the foothills, perhaps in search of other food; and it would be interesting to learn what that food is. It has been seen foraging on the ground, as well as in the foliage, and flying up into the air to capture insects on the wing.

_Behavior._--Virginia's warbler is a shy, retiring species, spending most of its time not far above the ground in the thick underbrush, where it is not easily seen, as its colors match its surroundings. It is also very lively and active, almost constantly in motion, except when it mounts to the top of some dead bush or small tree to sit and sing.

_Voice._--Dr. Chapman (1907) quotes C. E. Aiken as follows: "The male is very musical during the nesting season, uttering his _swee_ ditty continually as he skips through the bushes in search of his morning repast; or having satisfied his appetite, he mounts to the top of some tree in the neighborhood of his nest, and repeats at regular intervals a song of remarkable fullness for a bird of such minute proportions." Henry D. Minot (1880) calls the "ordinary note, a sharp _chip_; song, simple but various (deceptively so); common forms are _ché-we-ché-we-ché-we-ché-we, wit-a-wi't-wi't-wi't_ (these terminal notes being partially characteristic of _Helminthophagae_) and _che-wé-che-wé-che-wé, ché-a-ché-a-ché_". Dr. Linsdale's (1938) comments on singing males follow:

The song varied from 7 to 10 notes, being usually 8, and it occupied about 3 seconds. At the beginning the notes were slow and they came more rapidly at the end. About half a minute elapsed between songs. Another bird sang 14 times in 3 minutes and 10 seconds. * * * Singing perches on dead limbs that were rather exposed were the rule, but they were not often as high as the tops of tall trees. * * * On June 16, 1930, near Kingston Creek, 7500 feet, a singing male was followed for an hour, beginning at 7:30 a. m. It sang about every 30 seconds. The territory over which it moved was surprisingly large, estimated as extending 400 yards along the cañon slope and vertically about 150 yards, from near the stream to the base of the broken cliffs. * * * The song, compared with that of the Tolmie warbler had a more rapid rhythm and the notes were thinner and weaker. It could be distinguished from that of the Audubon warbler by the lack of rising inflection at the end. The song was represented by the observer (Miller) as _zdl-zdl-zdl-zdl, zt-zt-zt-zt_.

_Field marks._--Virginia's warbler, with its plain gray upper parts, is an inconspicuous bird, and its shy, retiring habits make it difficult to observe. The chestnut crown patch is not prominent and is often invisible. The yellow on the chest and throat of the male is quite variable and in the female and young much reduced or lacking. The best field marks are the dull yellow rump and upper and under tail covers, which are more or less conspicuous in old and young birds at all seasons.

_Enemies._--O. W. Howard (1899) says that "the nests of the bird, like those of other ground-nesting birds of this locality, are destroyed by jays and snakes. The jays steal both eggs and young. Often a whole band of these winged wolves will sweep down on a nest and in less time than it takes to tell it they will devour the contents and destroy the nest, the pitiful notes of the helpless parents being drowned by the harsh notes of the marauders."

Frank C. Cross writes to me that Robert J. Niedrach showed him a nest of this warbler that contained a young cowbird and one young warbler.

_Winter._--By the last of August or early September, Virginia's warblers have retired from their northern breeding haunts, to spend the winter in southern Mexico. Dr. C. William Beebe (1905) writes: "Occasionally in the mornings, numbers of tiny grayish warblers came slowly down the walls of the _barranca_, feeding as they descended, taking short flights, and keeping close to ground among the dense underbrush. These birds lingered at the camp for a time, and then, with soft, low chirps, all passed on to the water, where they alighted on the sand and drank. Then, as if at some silent signal, all flew up and returned quickly, still keeping close to the ground, zig-zagging their way upward in a long line, like tiny gray mice." These were, of course, Virginia's warblers.

DISTRIBUTION

_Range._--Western United States to Southern Mexico.

_Breeding range._--Virginia's warbler breeds =north= to central eastern California (White Mountains); central and northeastern Nevada (Kingston Creek, Ruby Mountains, and East Humboldt Mountains); northern Utah (Salt Lake City, Parley's Park, Packs Canyon, and Ashley); possibly southeastern Idaho (Joe's Gap, Bear Lake County; one specimen from Bancroft, Bannock County); and northern Colorado (probably Little Snake River, Moffat County, and Estes Park). =East= to the eastern slope of the Rocky Mountains in Colorado (Estes Park, Denver, Manitou, Fountain, and Beulah); in migration has occurred east to Limon, and Monon in Baca County close to the Kansas line; and central New Mexico (Tierra Amarilla, Lake Burford, Sandia Mountain, and Apache, probably). =South= to southwestern New Mexico (Apache); and southeastern Arizona (Paradise and the Huachuca Mountains). =West= to southeastern and central Arizona (Huachuca Mountains, Santa Catalina Mountains, and Prescott); and eastern California (Clark Mountain and White Mountains; casually in migration to Lemon Grove).

_Winter range._--In winter Virginia's warbler is found in west central Mexico from northern Jalisco (Bolanas); and Guanajuato (Guanajuato), to Morelos (Yautepec); and Guerrero (Talpa and Chilpancingo).

_Migration._--A late date of spring departure is: Sonora--Moctezuma, May 10.

Early dates of spring arrival are: Texas--Socorro, April 20. New Mexico--Cooney, April 10. Colorado--Estes Park, May 2. Arizona--Madera Canyon, Santa Rita Mountains, April 2. Utah--Vernal, May 5. Nevada--South Twin River, April 30.

Late spring migrant in Brewster County, Tex., May 13.

Late dates of fall departure are: Utah--Vernal, September 20. Arizona--Tombstone, September 11. Colorado--Boulder, September 21. New Mexico--Koehler Junction, September 11. Texas--El Paso, September 16.

Early dates of fall arrival are: Arizona--Toprock, July 23. Texas--Toyavale, August 21. Sonora--Guadalupe Canyon, August 31.

_Casual records._--Two specimens of Virginia's warbler have been taken in western California: in San Diego County, on September 3, 1931; and at Prisoner's Harbor, Santa Cruz Island, on September 8, 1948. Virginia's warbler has been reported as occurring in Nebraska and Kansas, but there is no record of a specimen having been taken in either State.

_Egg dates._--Arizona: 10 records, May 17 to June 21; 5 records, May 25 to June 4.

Colorado: 6 records, June 1 to 26.

Nevada: 3 records, June 8 to 15.

VERMIVORA CRISSALIS (Salvin and Godman)

COLIMA WARBLER

CONTRIBUTED BY JOSSELYN VAN TYNE

HABITS

Described in 1889 from a single specimen collected by W. B. Richardson in the Sierra Nevada de Colima, Mexico, this handsome warbler was, in 1932, still known from only a dozen museum specimens, and not a word had been recorded on its habits. In that year a University of Michigan expedition found the Colima warbler to be common in the higher forests of the Chisos Mountains of southwestern Texas and made the first discovery of its nest and eggs. The basis for the inclusion of this warbler in the A. O. U. Check-List had been a single specimen collected by Frederick M. Gaige in the Chisos in 1928 (Van Tyne, 1929).

The range of the Colima warbler has been recorded only very sketchily, but Bangs (1925) was probably correct in surmising that the specimens from southern Mexico (Colima and Michoacán) were migrant birds. The closely related Virginia's warbler, which nests in the Rocky Mountain States, winters mainly in Michoacán, Guerrero, and Jalisco. Recently R. T. Moore (1942) added a second, more southerly, locality in Michoacán and one in eastern Sinaloa to the known southern range of the Colima warbler. The breeding range is apparently restricted to the highlands of northeastern Mexico and the Chisos Mountains of southwestern Texas. In Texas the Colima warbler occurs at altitudes between 6,000 and 7,500 feet (Van Tyne, 1936); in Coahuila, apparently, only above altitudes of approximately 7,500 feet (Burleigh and Lowery, 1942). Records from the southern part of its range, however, show a greater altitudinal spread. The type specimen was taken in Colima at about 8,000 feet, and R. T. Moore (1942) reports two November specimens, one taken at 9,500 feet in northeastern Michoacán, the other at 5,200 feet in Sinaloa. These represent the extremes of the known altitudinal range.

_Courtship._--Mating behavior has been observed during the first few days of May and sets of eggs noted May 15 (just completed) and May 20 (highly incubated). The only recorded specimen in juvenal plumage was collected July 20. Peet observed pursuit behavior in the Chisos Mountains on May 4 (within a few days of nest building), which may have had some courtship significance, but nothing definite is known of the courtship habits. Sutton noted copulation twice on May 1 in the Chisos, and the gonads of specimens collected that day were much enlarged; there was no indication that the females had begun incubating.

_Nesting._--Two nests, both in the Chisos Mountains, have been described. The first (discovered in 1932) was lodged between small rocks and deeply imbedded in dead oak leaves on the sloping bank of a dry stream bed. A dense ground cover of vines and other herbaceous plants arched completely over it, leaving an entrance only on the northwest side, toward the stream. The nest had a basic structure of loosely woven fine grasses, the outside reinforced with pieces of green moss and the rim with strips of cedar bark; the cavity (5 centimeters across the rim and 4 centimeters deep) was lined with fine grass, a little fur, and a few hairs (Van Tyne, 1936). The other nest, which was "on the ground, under a little bunch of oak leaves, at the edge of a talus slope, almost at the very base of the cliffs" (Sutton, 1935), was similar, but its basic structure included dry leaves, and the site was concealed by only a partial canopy of leaves (Van Tyne and Sutton, 1937).

Nest building was observed in the Chisos Mountains on May 7, 1932 (Van Tyne, 1936):

As I was crossing the dry stream bed about a hundred yards below Boot Spring, I suddenly saw within twenty-five feet of me a female warbler with nest material in her bill. I stopped instantly and, remaining motionless, was greatly relieved to see the warbler continue undisturbed by my presence. In a moment she dropped to the ground and entered the nest, which was on the sloping right bank of the stream about six feet back from the margin of the rocky stream bed. After working for about twenty seconds the warbler left the nest and flew down the stream bed a hundred and fifty feet. In twelve minutes she was back with more nest material to repeat the performance. Subsequent excursions for building material during the ensuing hour were of three, twelve, six, and twenty-two minutes' duration. Each time she worked at the nest only fifteen to twenty seconds, until the last trip (at 11:43 A. M.) when she worked about two minutes and then departed, probably to feed, for she did not return again while I watched. Each trip to the nest had been made undeviatingly, without any hesitation, from the stream bed or from the forest to the west. Alighting almost directly above the nest, without a pause she dropped through the branches by three or four stages and promptly entered the nest, placed the material, and snuggled down working it into place. After a few moments she seemed to have completed this to her satisfaction, and, leaving the nest, she flew up to the branches ten or twelve feet above, fed for a few moments on the insects among the fresh green leaves of the little oaks and maples, and went away for more material.

When it was evident that the nest building was over for the time I went over to the nest and, examining it more closely, found that it was nearly built. The following day, May 8, it seemed to be finished.

_Eggs._--Two complete clutches have been found, each containing four eggs. Four eggs collected and measured were 18 by 13.3, 18 by 13.5, 18 by 13.5, and 18.5 by 14 millimeters. They were creamy white, speckled, and blotched in a wreath at the larger end with "vinaceous fawn," "light brownish drab," and "cinnamon drab."

Egg laying, in the one instance observed, was at daily intervals (May 12-15); the first egg was laid four days after completion of the nest. Incubation had begun May 16, the day after the last egg was laid. The length of the incubation period is not known. Females collected on May 12 (Peet), May 17 (Van Tyne), and May 20 (Sutton) had well-marked incubation patches; males collected at the same time had no patch.

_Plumages._--The Colima warbler differs from its nearest relative, the Virginia's warbler, in being larger; darker, less gray, above; crown paler; rump and upper tail coverts darker and richer in color; yellow of throat and breast absent or, if present, more green and more diffuse; sides and flanks more brownish; crissum darker, more aniline yellow; sexes much more nearly alike. The adult female Colima warbler is slightly darker than the male and is more brown below. It is apparently never yellow on the breast.

The juvenal plumage (known from only one specimen) differs from the adult plumage in lacking the crown spot and in having two buffy wing bars. The rump is also much more yellow (less green) and the crissum is more yellow (less orange). The young Colima warbler differs from the young Virginia's warbler in having a larger bill, darker plumage, and a less ochraceous rump.

The fall plumage differs from that of the spring in being "darker and browner throughout, the gray of head a good deal obscured by deep olive or light brownish olive; crown patch orange rufous; under parts darker with whitish area in middle of belly more distinct and under tail-coverts duller, more nearly aniline yellow" (Bangs, 1925).

George Miksch Sutton's fine color plate (Van Tyne, 1936, frontispiece) of the Colima warbler is apparently the only published figure of the species.

_Behavior._--In Texas, the Colima warbler was observed feeding on insects (which were not identified), but nothing further has been recorded about its food. All observers seem to agree that it is not a shy bird, although in its preferred cover, the female seems elusive and nests are difficult to find. Sutton has remarked that they are "rather deliberate, even vireo-like in their movements" (Van Tyne and Sutton, 1937). In the Chisos Mountains, they frequented especially the young maples and deciduous oaks along the banks of the dry, boulder-strewn stream bed, and elsewhere on the steep mountain slopes their preference for clumps of small oaks was noted.

_Voice._--The call note of the Colima warbler is a very sharp, almost explosive _psit_. Its common song is a continuous trill, like that of the chipping sparrow, but shorter (lasting 3 to 4 seconds), more musical, and ending with two separate notes slightly lower in scale. A second, rarer, and more varied song is so clear that it can be heard for three or four hundred feet through the woods although it does not seem loud when heard from nearby. It is perhaps this song that Brandt (1940) describes as resembling the song of the eastern redstart. E. C. Jacot (MS.) reports that the males usually start singing when "a person approaches the territory of a pair, and continues to sing until the intruder has passed." In the Chisos Mountains, Tex., the males were persistent singers. Once several sang even after a dense fog had silenced most other species. They sang usually from bushes and small trees between periods of feeding and moving about but sometimes remained for a while on a higher perch (up to 20 feet), singing at frequent intervals.

DISTRIBUTION

_Range._--Chisos Mountains, Tex., and mountains of northeastern Mexico; probably winters in Colima, Michoacán, and Sinaloa.

The Colima warbler has been recorded from: Texas (Chisos Mountains); Coahuila (Sierra Guadalupe and Diamante Pass); Tamaulipas (Miquihuana); Michoacán (Patamba and Sierra Ozumatlan); Sinaloa (5 miles north of Santa Lucia); Colima (Sierra Nevada).

_Egg dates._--Texas: 2 records, May 15 and 20.

VERMIVORA LUCIAE (Cooper)

LUCY'S WARBLER

PLATES 18, 19

HABITS

Dr. J. G. Cooper discovered this tiny and inconspicuous warbler at Fort Mojave, on the Arizona side of the Colorado River, in the spring of 1861, and named it in honor of Miss Lucy Baird, daughter of Prof. Spencer F. Baird. It might well have been named the mesquite warbler, as its distribution coincides very closely with that of this tree, which seems to furnish its favorite home, most of its nesting sites, and much of its foraging area.

Harry S. Swarth (1905) wrote of conditions then existing:

South of Tucson, Arizona, along the banks of the Santa Cruz River, lies a region offering the greatest inducements to the ornithologist. The river, running underground for most of its course, rises to the surface at this point, and the bottom lands on either side are covered, miles in extent, with a thick growth of giant mesquite trees, literally giants, for a person accustomed to the scrubby bush that grows everywhere in the desert regions of the southwest, can hardly believe that these fine trees, many of them sixty feet high and over, really belong to the same species. This magnificent grove is included in the Papago Indian Reservation, which is the only reason for the trees surviving as long as they have, since elsewhere every mesquite large enough to be used as firewood has been ruthlessly cut down, to grow up again as a scraggly bush.

But this magnificent forest did not long remain in its pristine glory. When I was in Arizona with Frank Willard in 1922, we had looked forward with keen anticipation to visiting the mesquite forest, where he had told me that we should find a thick stand of big trees covering a large area, and some wonderful bird life. We were disappointed in the forest, for the Papago Indians had been cutting down the larger trees unmercifully and had made a network of cart roads all through it for hauling out the firewood. There were only a few large trees left, more or less scattered, and between them many open spaces in which were thickets of small mesquites and thorn or patches of medium-sized mesquites and hackberries. But we were not disappointed in the bird life, for here and in other parts of Pima County, wherever there were mesquites, we found Lucy's warblers really abundant and breeding. The forest fairly teemed with bird life, from the graceful Mexican goshawks soaring overhead to the Gambel's quails whistling on the ground. The constant cooing of the white-winged doves was almost too monotonous, but the rich song of the Arizona cardinal, mingled with the voices of the orioles, towhees, wrens, and vireos made a delightful chorus, among which the sweet song of Lucy's warbler was prominent.

Dr. Joseph Grinnell (1914) writes, referring to the Colorado Valley: "On the California side, both at Riverside Mountain and above Blythe, Lucy warblers were numerous, and very closely confined to the narrow belt of mesquite. The singing males, each representing the forage area and nesting site of a pair, were spaced out very uniformly, so that an estimated strip of about 200 yards in length belonged to each. The birds foraged out to a limited extent from the mesquites towards the river into the arrowweed and willows, and away from the river at the mouths of washes into the ironwoods and palo verdes. But the metropolis was always most emphatically the mesquites."

_Nesting._--M. French Gilman (1909) had considerable experience with the nesting habits of Lucy's warbler along the Gila River in Arizona, of which he says:

Four general types of nesting sites were noticed, in the following order of frequency: in natural cavities, under loose bark, in woodpecker holes, and in deserted Verdins' nests. Of 23 nests observed, 12 were in natural cavities, 4 under loose bark, 4 in woodpecker holes, and three in Verdins' nests. Natural cavities were of various kinds. Some were where a limb had been broken off; others in the crack made by a large branch splitting from the trunk; and again a decayed spot furnisht a sufficient hollow to conceal the nest. In all cases the site was in a sheltered or protected position; that is, the trunk leaned enough to shade the entrance from above. A mesquite tree was usually selected, tho others were taken. Of the nests observed, 15 were in mesquites, 5 in palo verde, 2 in ironwood, and one in catsclaw. * * *

The nests were small and compact and well hidden in their cavity. Only twice did protruding material betray the location. In one case nesting material protruded from a woodpecker hole, and the other was a bulky nest that showed from each side of a split branch. This last nest I thought must belong to a House Finch, but investigation showed warbler ownership. Nests were made of bark, weeds, and mesquite leaf-stems, and lined with fine bark, horse and cow hair, a few feathers and sometimes a little rabbit fur. The site averaged six and one-half feet from the ground, the lowest being 18 inches and the highest 15 feet. * * *

In nest-building the female seems to do all the work, her mate sometimes accompanying her on trips to and from the tree, but more frequently flitting about the tops of adjacent trees, occasionally uttering his little warble. One pair I watcht had a nest in a Texas Woodpecker hole in a palo verde tree about 15 feet from the ground. The female brought material to the nest three times in two minutes, then a seven minute interval, followed by two trips in three minutes. The male accompanied her on two trips then made himself scarce. He indulged in no singing and both birds were silent, tho in many cases one or both gave the call note at intervals.

Others have mentioned nests of Lucy's warblers in verdins' nests, probably all old winter nests of the male verdin, relined to suit the warbler. O. W. Howard (1899) records such a nest and adds: "Other nests were placed in crevices along river banks where roots of trees were sticking out and one or two were found in natural cavities of the Giant Cactus, or in woodpecker holes therein." We found a nest with young in a cavity in the bleached skeleton of a fallen giant cactus, where I set up my camera and took several photographs of the bird feeding the young. A very pretty nest of this warbler is in the Thayer collection in Cambridge; it was evidently built in the fork of a mesquite limb, supported by a cluster of old and fresh, green twigs; it is made externally of the leaves, petioles, fine green twigs, and flower clusters of the mesquite and is decorated with a few feathers of the white-winged dove; it is lined internally with fine fibers, white cows' hair and black horsehair, and more dove feathers; it measures 4 by 3 inches in outside diameter and 2 by 1-1/3 inside; the outside height is nearly 3 inches, and the inside cup is about 1-3/4 inches deep. A set in my collection was taken from a hole 3 feet above the base of a sandy bank along a wash near the San Pedro River, in Arizona.

_Eggs._--Lucy's warbler lays from 3 to 7 eggs, but the set usually consists of 4 or 5; the larger sets are rare, but O. W. Howard has found two sets of 7, and several sets of 6 have been recorded. The eggs are ovate to short ovate and have very little lustre. The white or creamy white ground color is finely speckled with shades of "chestnut," "bay," or "auburn." The eggs that have markings in the darker shades of "chestnut" and "bay" frequently have a scattering of minute spots of "brownish drab" that are often lacking on eggs with the lighter markings of "auburn." The spots are usually concentrated at the large end. The measurements of 50 eggs average 14.6 by 11.4 millimeters; the eggs showing the four extremes measure =16.5= by 11.5, 14.6 by =12.0=, =13.2= by 11.2, and 13.7 by =10.7= millimeters. (Harris.)

_Young._--The period of incubation seems to be unknown, and I can find no information on the development and care of the young. Evidence points to the conclusion that incubation and brooding are performed entirely by the female, and that at least two broods are reared in a season. Mr. Swarth (1905) says that "several broods are probably raised, as unfinished nests and incomplete sets were found at the same time that broods of young as large as the adults were seen flying about."

_Plumages._--Ridgway (1902) says that the young in juvenal plumage are "essentially like adults, but much clearer white beneath; no trace of chestnut on crown; upper tail-coverts ochraceous-buff instead of chestnut; middle and greater wing-coverts tipped with whitish or pale buffy, producing two rather distinct bars." He might have added that the tertials are edged with cinnamon, and that the primaries and rectrices are edged and tipped with white.

There is apparently a partial postjuvenal molt, some time during the summer, when all the plumage except the flight feathers, remiges, and rectrices, is renewed. Young birds now become very similar to adults, but can be recognized by the juvenal wings and tail until the edgings wear off. I can find no evidence of a prenuptial molt in either young or old birds. I have seen adults in complete postnuptial molt in August. Fall birds are tinged with brown above and with pale brownish buff below; the chestnut crown patch is concealed by very broad brownish gray tips. Females are not always distinguishable from males, but usually the chestnut on the crown and upper tail coverts is paler and more restricted.

_Food._--Nothing definite seems to have been published on the food of Lucy's warbler, but it is evidently largely, if not wholly, insectivorous, as it is often seen foraging in the foliage and flower clusters of the mesquites and in other trees. Dr. W. P. Taylor tells me that he has seen it feeding on the pendant sprays of ocotillo flowers, probably gleaning insects or other materials from the exterior. In late spring when the mesquites, palo verdes, the various cacti, and even the saguaros burst into full bloom, these gorgeous desert plants are a blaze of color and attract myriads of insects.

_Behavior._--Mr. Gilman (1909) says that "shyness about the nest seems to be characteristic of these birds." He was seldom able to flush one from its nest. "In three cases only, did the parent birds show what might be called proper amount of solicitude when the nest was approacht. Some of them seemed rather touchy about their nests, leaving them if the nest were toucht even so lightly." Some nests, with incomplete sets, were deserted after they had been inspected; but others were not. "They took good care not to sing in the nest tree, preferring to confine their performances to trees some distance away. The male would frequently meet me several rods from the nest and flit from tree to tree singing at short intervals. Once I made a complete circuit of the nest tree and he accompanied me the entire distance. This was an exceptional case of course. While going from tree to tree and singing, the bird usually tried to keep hidden as much as possible and was rather successful in the effort."

However nest-shy the bird may be when there are eggs in the nest that she does not want discovered, the bird that I watched was not at all shy about her nest, nor was she lacking in parental devotion. For, although my camera stood within a few feet of the nest and I was standing beside it in plain sight, she came repeatedly to feed her young. I should say that these birds are more retiring than shy.

W. L. Dawson (1923) writes: "Albeit an active creature and zealous in song, the Lucy Warbler becomes almost invisible in its habitual setting, and the difficulty of detection is heightened by the bird's instinctive wariness. Again and again I have known a bird which had seemed quite engrossed in song to fall silent at the stir of a footstep a hundred yards away."

_Voice._--Mr. Dawson (1923) says: "The Lucy Warbler is a loud and industrious singer, but the song has a curious generic quality very difficult to describe. It is _Warbler_ song, rather than the song of the Lucy Warbler. It is, perhaps, most like that of the Pileolated Warbler (_Wilsonia pileolata_) in quality. After that, it reminds one of the Yellow Warbler's song, having the same vivacious cadence, but not being so sharply piercing. Again its breathless, haphazard quality suggests one of the Buntings; and I once followed its tantalizing seductions for half an hour under the delusion that I was on the track of the coveted Beautiful Bunting (_Passerina versicolor pulchra_)."

Dr. Grinnell (1914) says that the song "resembles the song of the Sonora yellow warbler in length and frequency of utterance and somewhat in quality, but with a distinct hurried and lisping effect reminding one of the song of the Lazuli bunting." Several others have noted the resemblance to the song of the yellow warbler. Mrs. Florence Merriam Bailey (1923) puts the song in syllables as follows: "_whee-tee, whee-tee, whee-tee, whee-tee, whee-tee, whee-tee, whee-tee, whee-tee, whee-tee, wheet_, and its call was a faint _chip_."

_Field marks._--There are no very striking marks on Lucy's warbler; it is clothed in quiet colors and in general appearance suggests a warbling vireo. The chestnut crown patch of the male can be seen under favorable conditions, but on the female it is seldom in evidence. The chestnut upper tail coverts can be seen only when the bird is in certain positions. Its activity will mark it as a wood warbler, and it is the only one of this family likely to be found on its breeding grounds among the mesquites in the nesting season.

_Enemies._--Mr. Howard (1899) says that "many nests are destroyed by wood-rats and snakes." And Mr. Dawson (1923) writes:

Dwarf Cowbirds are prominent in the formidable host of enemies which this tiny bird must face. Sometimes the warblers are able to entrench themselves behind apertures so narrow that the Cowbird cannot get in; and once we saw the Cowbird's foundling resting unharmed, but also harmless, upon the "doorstep," not less than two inches distant from the warbler's eggs. Another nest, more exposed, contained three eggs of the arch enemy, and had been deserted by the troubled owners. The Gila Woodpecker is an especially persistent enemy. Accustomed as he is to poking and prying, he seems to take a fiendish delight in discovering and devouring as many Lucy Warblers' eggs as possible. We caught several of these villains red-handed, and we found reason to believe that more than half of the nests in a certain section had been wrecked by them. Add to these the depredations of lizards, snakes, and, possibly, rats, and the wonder is that these tiny gray waifs are able to reproduce at all.

DISTRIBUTION

_Range._--Southwestern United States to central Mexico.

_Breeding range._--Lucy's warbler breeds =north= to southern Utah (Beaverdam Wash, Zion National Park; Calf Creek, Garfield County; and the San Juan River); and southwestern Colorado (Montezuma County near Four Corners). =East= to Colorado (near Four Corners); western New Mexico (Shiprock, possibly San Antonio, mouth of Mogollon Creek, and Redrock); southeastern Arizona (Bisbee); and northeastern Sonora (Moctezuma). =South= to northern Sonora (Moctezuma and Sáric); southern Arizona (Baboquivari Mountains, Menager's Dam, and Gadsden); and southern California (Picacho and Silsbee). =West= to southern California (Silsbee, Mecca possibly, and Chemehuevis Valley); western Arizona (Fort Mojave); and southwestern Utah (Beaverdam Wash).

_Winter range._--The few available records place the winter home of Lucy's warbler in central western Mexico from Jalisco (Bolaños and Lake Chapala) to eastern Guerrero (Iguala).

_Migration._--Few migration dates are available for a species with such a limited range. Early dates of arrival are: Arizona--Tucson, March 12. California--Mecca, March 29. Utah--St. George, March 23. A late departure date is: Arizona--Tombstone, October 3.

_Egg dates._--Arizona: 58 records, April 22 to June 27; 30 records, May 2 to 21, indicating the height of the season.

PARULA AMERICANA PUSILLA (Wilson)

NORTHERN PARULA WARBLER

PLATES 20, 21

HABITS

I have always preferred the old name, blue yellow-backed warbler, as originally used by Wilson and Audubon, to the modern common name; it seems more descriptive of this dainty wood warbler. As to the origin of this newer name, Dr. Spencer Trotter (1909) writes: "The name 'parula' recently in vogue for the warblers of the genus _Compsothlypis_ is clearly borrowed from the old Bonaparte genus _Parula_ (diminutive of titmouse). The bird (_C. americana_) has appeared under various titles--'the Finch Creeper' of Catesby (I, 64), 'the various coloured little finch creeper' of Bartram (Travels, 292), and the 'Blue Yellow-backed Warbler' of Wilson, Audubon, and later authors." _Parula_ was extensively used as the generic name during the last century, and is now reinstated to replace _Compsothlypis_.

The 1931 A. O. U. Check-List of North American Birds recognizes only two races of this species, the subject of this present sketch, _P. a. pusilla_, and the southern race, _P. a. americana_. The two forms together occupy a breeding range covering practically all of the United States east of the Great Plains, as well as parts of southern Canada, the type name being restricted to the birds breeding from the District of Columbia southward to Alabama and Florida.

Ridgway (1902) describes the northern bird as "similar to _C. a. americana_, but slightly larger, with smaller bill and darker, richer coloration; adult male with blue of upper parts deeper, and black of lores more intense; lower throat or upper chest (sometimes both) blackish or dusky (the feathers sometimes tipped with chestnut), forming a more or less distinct, often very conspicuous band; lower chest orange-tawny, tawny, or chestnut (the feathers usually margined with yellow) forming usually a distinct and often abruptly defined patch; sides usually more or less tinged or spotted with chestnut."

In the same work, he describes a third form, _C. a. ramalinae_, as "similar in coloration to" the northern bird, "but smaller even than _C. a. americana_." He gives as its range the Mississippi Valley, from Mississippi, Louisiana, and Texas to Minnesota and Michigan. This western race is not recognized in the 1931 A. O. U. Check-List.

Our experience with the northern parula warbler in Bristol County, Mass., well illustrates the successive changes that nature and man have wrought in the distribution of so many of our birds. Many years ago, perhaps early in the last century or before, some hardy pioneers hewed out a clearing in the forest that clothed the slopes of Rocky Hill in Rehoboth, Mass., planted an apple orchard, and surrounded it with stone walls. All traces of the old farm, if ever there had been one, disappeared before I first visited the locality in 1888, and the forest had begun to encroach on the old clearing. The apple trees even then showed signs of old age and were profusely covered with long festoons of that picturesque tree lichen, often called beard-moss or old-man's-beard (_Usnea barbata_, _U. longissima_, or _U. trichodea_). This old orchard was a mecca for all local oologists, and many a set of eggs of the blue yellow-backed warbler was taken from it during succeeding years. As time passed, the old trees gradually died, the _Usnea_ disappeared, the warblers ceased breeding there, and the forest eventually reclaimed the land until today only the ancient stone walls remain to mark the locally famous haunt of the blue yellow-backs.

I can remember several other old, neglected orchards that were similarly decorated with the long, gray-green lichen and that were inhabited by parula warblers as nesting sites, but they all suffered the same fate; the orchard trees decayed and were replaced by woods and thickets. During the early part of the present century this warbler continued to breed commonly in Bristol County wherever it could find trees infested with _Usnea_--around the edges of swamps and along the shores of ponds, lakes, and sluggish streams; but now this lichen seems for some reason to have entirely disappeared from the County, and the parula warbler has likewise disappeared, although it may still breed in a few similar localities on Cape Cod, Mass., where I have found it a few times in more recent years.

Localities such as those described above seem to be typical of the breeding haunts of the northern parula warbler, at least in New England, southern New York, and New Jersey. Whether the presence of _Usnea_ is a sine qua non for the breeding haunts of this wood warbler is an open question; but it may safely be said that where this lichen grows in abundance one is almost sure to find it breeding; and conversely, where this lichen is scarce or lacking, the warbler breeds sparingly or not at all.

Farther westward, northward, and southward, where _Usnea_ is scarce or entirely absent, these warblers seem to find congenial haunts in hemlock ravines and in other coniferous woods and swamps; but even there they are more likely to be found where there is at least some of one species or another of this lichen, or where the somewhat similar Spanish moss (_Tillandsia usneoides_) grows.

_Spring._--Parula warblers that have wintered in the West Indies reach southern Florida during the first week in March. Dr. Wetmore (1916) says that it "was the most common of the migrant warblers in Porto Rico. * * * Migratory movement was apparent among them by February 14, and after this the birds were very restless, especially during early morning, and there was tendency to work from the east to west. In March and April there were distinct waves of migration." But it is well on toward the middle of May before the first migrants reach the northern limits of their breeding range.

Professor Cooke's (1904) records show that the migrants from Mexico and Central America reach the Louisiana coast by the very last of February or early March, while the first arrivals on the lower Rio Grande, in Texas, come two or three weeks later. He observes:

A comparison of the dates shows, first, that the parula warbler arrives in Texas much later than in either of the other States, and hence does not reach the Mississippi Valley by way of Texas; second, that it arrives in northern Florida at least ten days later than it attains the same latitude in Louisiana. From these two facts it would appear that Louisiana is reached by direct flight across the Gulf of Mexico. The average date of arrival at New Orleans coincides closely with the date when the first migrants arrive at the southern end of Florida. It would seem that the birds of Mexico and Cuba are prompted to move northward at the same time, but the flight over the Gulf of Mexico being so much longer than that from Cuba to Florida, the Mexican birds reach a higher latitude by their initial flight.

There are other interesting details in Cooke's account to which the reader is referred.

During migration the parula warbler does not frequent haunts typical of its breeding ground; in fact such are not to be found in much of the country over which it travels; nor does it especially frequent the coniferous woods to which it is partial in summer. It is to be found almost anywhere, in many kinds of trees, though it seems to show a decided preference for deciduous woods. There, it may often be seen drifting through the highest tree-tops in mixed groups of migrating wood warblers, gleaning insects amidst the freshly opening foliage. Referring to the Buckeye Lake region in Ohio, Milton B. Trautman (1940) writes: "The transient Parula Warblers usually displayed a preference for large pin oak and shingle oak trees and a marked preference for one shingle oak in particular. This oak was in the Lakeside Woods, and more Parula Warblers were observed in it than in all of the remaining trees of the woodland. A transient often displays a marked preference for certain types of trees, but it appears unusual for a single tree among many of the same kind to retain yearly so marked an attraction for a particular bird species."

The migrating parula warbler is often seen in roadside trees and in shade trees in parks and gardens. It even visits our orchards, where one of the most charming sights of springtime is to see this gay-colored, tiny warbler flitting about in search of insects among the apple blossoms, a delightful bit of color contrast in a beautiful setting.

_Nesting._--The nests of the northern parula warbler that we used to find in southern Massachusetts were all located in haunts similar to those described, and mostly in old orchards heavily festooned with beard moss (_Usnea_). We could usually find three to five nests in a well-populated orchard, but they were so well hidden in the hanging moss that we may have overlooked some. A casual observer would never notice one, but with practice we learned to recognize a rounded, cuplike, thick place in a bunch of _Usnea_ as indicating a nest. The nests were usually made in bunches of moss that hung from horizontal or sloping branches and were from 5 to 15 feet above the ground, more being below than above 12 feet. Some nests were in red cedars, or savins (_Juniperus virginiana_), scattered among other trees or growing in open stands by themselves; they were located in bunches of _Usnea_ close to the center of the tree and often within reach from the ground. Occasionally, isolated trees on the edges of swamps or on the shores of ponds were sufficiently covered with the lichen to contain nests, and these were sometimes as much as 20 feet above the ground. The nearest approach to a colony that I ever found was in a small cedar swamp, not over an acre in extent, that jutted out from the shore of a lake into rather deep water.

The white cedars (_Chamaecyparis thuyoides_) were growing in water that was waist deep or more in places, and the whole place was so obstructed with fallen trees and sunken snags that it was very difficult to explore thoroughly; I managed to find some half a dozen nests, and there may have been others, for many of the trees were well "bearded."

The nests that we have found have all been very simple affairs, apparently merely pockets hollowed out in bunches of hanging _Usnea_, with side entrances slightly above the cups. Some nests were small and suspended only 2 or 3 inches below the supporting branch, practically open baskets accessible from directly above; others were found in long, thick bunches, a foot or more in length, with long streamers hanging below the nest. External measurements were therefore quite variable. Many of the nests were unlined, save with a soft bed of fine shreds of _Usnea_, some were scantily lined with a few pieces of fine grass, two or three pine needles, one or two horsehairs, or a few bits of buff-colored down from the stems of ferns; rarely, a nest was more elaborately lined with the latter material but never as profusely as are the nests of other wood warblers.

Apparently the nests were also difficult to find in Connecticut; "J. M. W." (C. L. Rawson, 1888), who has probably taken more eggs of the blue yellow-backed warbler than any other man, says that the older ornithologists did not realize "that the three Southern New England States were about the centre of its breeding range," until he began sending eggs to Dr. T. M. Brewer. Thomas Nuttall (1833) remarked: "The nest and eggs are yet unknown."

Rawson found the parula warbler nesting in colonies near Norwich, Conn., and says:

I know a swamp where may be found seventy-five pairs of these summer residents. The first time I visited the Preston colony on the 31st of May, I took eight sets of four. The first time I visited another large community in this county on June 5, on a point of land trending into salt water, I took eleven sets of four. * * *

The nests are built on dead or green trees, and on savins or deciduous trees, at varying heights. I took one from the single filament of moss caught on the green twig of a birch, within five inches of the ground, and others close to the trunks of great oaks fifty feet in the air. On the lower swamp, huckleberry brush in the littoral colony is a favorite site.

William Brewster (1906) mentions only one nest taken in the neighborhood of Cambridge, Mass., a region where _Usnea_ is scarce:

In shape and general plan of construction the nest closely resembles that of a Baltimore Oriole. It has no hole in the side but instead a wide-mouthed opening at the top through which the bird entered it as the Oriole enters her nest. The upper edges and sides were securely fastened to the fine terminal twigs of a drooping branch where the nest hung suspended among the evergreen foliage of the hemlock, precisely as the Oriole's hammock swings in the dropping spray of an elm. The Warbler's nest has a scanty lining of pine needles and fine grasses but it is otherwise composed entirely of _Usnea_, loosely woven or perhaps merely felted together, evidently by the parent birds. They must have been at some pains to collect this material, for the closest scrutiny on the part of a friend and myself failed to reveal more than a few small and scattered tufts of _Usnea_ in the surrounding woods.

Henry Mousley (1924, 1926, and 1928), of Hatley, Quebec, made three attempts to make complete studies of the home life of the northern parula warbler, none of which covered the whole cycle for reasons beyond his control.

The nests were suspended from the branches of coniferous trees, at heights ranging from 26 feet in a spruce to 40 feet in a balsam fir. One of these nests was watched for a total of 24 hours, from May 22 to 31, during the process of construction; during this time the male sang 549 times from a little birch and went with the female to the nest, but brought no material; the female, however, made 206 trips with material, an average of one load every 5.4 minutes. The nest was made entirely of _Usnea_, all brought in, and lined with "some black hair-like rootlets, with two bits of plant down"; it was strengthened with a few fine grass stems. It weighed only 100 grains, or .23 ounce! "Outside diameter 3.25, inside 1.75 inches; outside depth 2.50, inside 1.75 inches. The female after selecting some of the longest threads of the hanging bunch of _Usnea_, attached them to a little twig a few inches off, following this up with that curious process--inherent--of moulding the nest, which in this case, was really an acrobatic performance, there being of course no apparent nest to mould, just a few strands, through which the bird's tail and wings protruded."

Outside New England, where _Usnea_ is scarce, the nests are often built in hanging clusters of twigs of hemlocks or spruces, with the use of more or less of this lichen when available. In the lower Mississippi Valley, Spanish moss (_Tillandsia usneoides_) offers a popular substitute and is generally found growing in profusion. But some nests are built of various other materials. George H. Stuart, 3d, writes to me of a nest he found at Pocono Lake, Pa., on June 22, 1916: "This remarkable nest was placed in a horizontal limb of a spruce, 20 feet up and 12 feet from the trunk, near the tip and overhanging a road near the lake." It was "composed mainly of fine dry grasses and the thinnest of bark shreds, with a few bits of down, fashioned together oriole-like, though loosely, with a few coarse grasses projecting suggesting the handiwork of the magnolia warbler. The tiny basket was suspended from the under side of the branch, partially supported by inclining twigs. In form it is an inverted cone or pear, measuring 3 inches deep by 3 inches wide at the rim, the thin walls tapering down to a narrow, pointed bottom. The thinness of the walls in places revealed the eggs from a side view."

Mrs. Nice (1931) reports a curious nest, found by Mr. Kirn near Copan, Okla.; it was fastened to ivy leaves and to a stick which was hanging down, held by the vine. "In this hanging, swaying cluster about two feet long, the nest was built almost entirely of box elder blossoms held together by spider webs on the outside, and sycamore seed down on the inside with a light lining of fine strips of weed stems."

Several nests have been reported as built of various materials in bunches of leaves and other rubbish deposited by freshlets on branches over streams.

Because of the bird's habit of using various materials and sites in its nest building, it may be well to mention some nesting records from the southern Gulf States. Andrew Allison wrote to Dr. Chapman (1907):

The invariable nesting site is a clump of Spanish moss--where this it to be had; I have not observed nests from beyond the range of this plant. The nest is generally placed near the branch from which the long filaments of the 'moss' depend, so that it is well concealed. The height from the ground varies from about eight feet upwards. * * * The nest is nearly hemispherical in shape, opening directly upward. The usual material, in lower Louisiana, is thistle down, which is abundant during the nesting season. Animal hairs are not used, I think. A nest from Bay St. Louis was composed of the very black horse-hair-like inner fiber resulting from the decay of _Tillandsia_.