The variety that builds the most elaborate nest is the Baya Weaver (Ploceus philippinus). The Baya Weaver Bird is also found all over the subcontinent, Java, and Sumatra. The male resembles the female during the “off” season, but after the spring and autumn molts, he assumes a canary-colored crown and other yellow patches, well distributed over most of his otherwise brown and white body.
Baya Weaver Bird decoration is lost when there is no nesting to occupy his attention. The bird’s flocks are found in scrub, grasslands, cultivated areas, and secondary growth. Also, these birds are best identified for hanging retort-shaped nests woven from leaves. The Baya Weavers love to live and build in colonies, which they usually select for a convenient tank or a terraced rice field.
Being graminivorous animals, they find that paddy fields furnish valuable granaries for a food supply. The nests found in the Northern Province of Sri Lanka almost habitually hang from the north and east exposures of the trees. which they built, and thus are least endangered by the battering winds of the Southwest Monsoon.
Though much has been written about the amazing nests of Ploceus. There are several interesting points connected with their construction that have escaped most observers or that do not appear to have impressed writers sufficiently, and they propose, with the aid of a series of photographs taken in situ, to point out some of these curious happenings.
Tailor Bird does her best to conceal her nest, in which she succeeds admirably. The weavers build their homes quite in the open, where they can be seen by all men. There are a number of nests in a colony that have settled in a large tree growing in the center of Sri Lanka. They came and went as if no human being were near them.
Wherever placed, the main objects sought shelter from bad weather and safety from enemies. These provisions are reflected in the suspension of the nests on the sheltered side of a tree on branches detached from other limbs and in the peculiar form and swinging character of the nesting houses.
Baya Weaver is, however, one precaution always taken. The nest hangs free in the air and swings from the tree on which it is built in such a fashion that it cannot be approached from below or from neighboring branches, and when that end is accomplished, the birds may suspend their nests from quite low points, often not more than fifteen feet from the ground.
The terminals of palm fronds and other branchlets about twenty feet from the earth or the surface of a pond are our favorite sites. According to some writers, the weavers, instead of building a new nest once or twice a year, may repair an old one, the chief evidence of which is the color contrast between the nest and the old grass employed in the process.
Indeed, a tree colony of several dozen nests may exhibit, at the same time, a collection of structures that vary in age, from old specimens battered by months of wind and rain to new and fresh nests on which the builders are still working. In some of the latter, one to four white eggs may be hatching; others issue little chattering cries that betray the presence of hungry fledglings.
The shape of the Ploceine nest has been likened to various objects: retorts, inverted bottles, flasks, etc. But to Newton’s similitude comes nearest to it.’ He compares it to a stocking hung up by the toe, with the heel enlarged to receive the eggs, as entrance and exit are made through the leg. The material out of which the nests are made is mostly pliant grass stems and other tough fibers, especially strips of palm fronds.
The Baya weaver strips from the leaves of palms, plantains, agaves, and other stringy plants fine but very strong threads for the weaving process. The bird collects them in this manner. Usually, the bird bites a small piece from the base of the palm, sisal, hemp, or another fibrous plant, repeats the incision, and jerks his head away from the leaf, thus tearing off a fine cord, perhaps a line in breadth that corresponds to the length of the distance between the two incisions.
Baya Weaver examined with a lens this weaving material from many nests and believes the description to be the most accurate. Moreover, I have watched the birds repairing the exterior and arranging the material of their nests and have often seen them tugging at a length of the fiber, part of which has already been woven into the nest. I have also seen them flying in the air with the free end of a strand in their bills, so that it might be drawn taut and smooth before inserting it beneath other fibers for the support of the nest wall.
As a preliminary to the construction of the nest proper, the birds wrap a considerable amount of fibrous material around a chosen limb or frond. Often, it is as much as three or four feet from the top of the pendant next to the further end of this anchorage, thus securing a firm hold upon the tree. The small strips are not only wound around the branch but are plaited together so securely that it is impossible, with an ordinary effort, to separate them.
The plaiting is then continuous downward from the branch to form a stout aerial stalk from 3 or 4 inches to a foot in length. The end of which is evidently expanded into the globular structure of the nest proper. The long diameter of this bulb is from 5 to 6 inches; its short diameter is about four.
Having shaped this upper chamber and located the future egg chain bet, the birds next build a strong, compactly woven transverse band or bridge that divides the lower part of the space into two unequal chambers. In every large colony, there are what look like unfinished nests that do not get further than this perch or roost stage, looking like an inverted basket with a handle.
So far as they go, these structures seem strong and well-finished, giving rise to many speculations as to their status. Are they made with an excess of home-building zeal by the male bird, upon whose feet and beak time hang heavily? Or, are there shelters to which he may retreat and rest, secure from the torrential monsoon?
The main argument favoring this hypothesis is, of course, The finished appearance in various cases of the canopy itself, its thick, smoothly plaited walls Hence, the rounded edges of the perch and the absence of any attempt to complete the base of the globular chambers or the entrances pout. It is suggested that the canopy is a nest deserted after partial construction on account of some fault in it an egg chamber too small, a neck not strong enough, etc.
Whether the canopy is deliberately planned as a shelter for one or both birds, or whether it is only a partially built and deserted nest, there can be no doubt that the non-incubating male has been seen occupying the structure and using it as a perching convenience, and there is no doubt that, whatever the original purpose of these structures, the canopy does make an admirable refuge from the wind, rain, and hot sun.
The illustrations show more clearly than any description of the forms and the relative size of the completed nests and so-called canopies both before and after removal from the tree colony. One colony, placed in a Halamba tree, furnished four canopies, as well as two full-lengths and one short nest. On the ground under the tree picked up, evidently detached by the wind, were five full-length and two short-tube nests.
In another tree, there are seven canopies and five nests. Three egg chambers held a single egg, and two had two eggs each. All the canopies had them on or near their margins. further the small lumps of dried mud, about which something further will be said; on the other hand, very few nests showed these deposits. The lowest structure was 12 feet from the ground. The average was 16 feet, and the highest was about 25 feet.
A small but, for many reasons, interesting colony had nested in a Damba tree. It numbered two canopies: one definitely unfinished nest, one long (with its entrance tube measuring fifteen inches), and two completed but shorter nests. The long nest contained fledgling inches.
The length of the shortest tube was 3 inches; the others varied from 6 to 15 inches. The circumference of the smallest nest was 14 inches; that of the largest was 18.50 inches. The longest nest measured, overall, 37 inches; the shortest was 17 inches.
As for the four canopies, the total length of the shortest was 12.75 inches; of the longest, 16.50 inches. The height of the chamber varied from 4 to 6.50 inches. Thus, the width of the bridge or perch is one-half to one inch. The diameters are the two entrances, from 2.25 by 3.75 inches to 3.50 by 2.50 inches.
The circumference of the largest canopy was 20 inches; the smallest was 15 inches. Hence, one sees that the nests and canopies vary noticeably in size and capacity. The smaller of the two cavities divided by the transverse roost or perch is the one continued into the long tube-like entrance. As soon as the egg chambers finished. The female bird confines her concentration to the completion of the interior of the nest and leaves the work on its exterior to the male.
They seem to work together, although the male gathers most of the building material, which he pushes through the walls. It is then woven back and forth as long as possible, that is, until thick, tough, solid, basket-like walls are the result. The male bird now completes the entrance spout, strengthens the walls of the upper nest, and, in some instances, begins a second nest like the structure already mentioned. During the nest building, both birds enjoy them thoroughly.
Also, the male Baya weaver often sings a little song when he joins his mate in weaving the nest material. Even after the eggs have been laid and the female has commenced incubating, the male continues to lengthen the entrance tube and put what he regards as the finishing touches on his house.
Also, it is often seen him diligently pushing fibers into place and pulling them back and forth on the surface of the nest to the accompaniment of a sweet little warble. I have never found a smooth, firm margin on the end of any entrance tube; it is always frayed, thin, and loosely woven, presenting a decidedly unfinished appearance.
The length of the cylindrical entrance tube—generally two inches in diameter—varies greatly, as will be seen in the illustrations. Indeed, the longest one I ever saw was in the private aviary of Mr. Shore-Bailey of Westbury, England, who has been very successful in breeding these birds in captivity. One of his nests has an entrance tube that is more than thirty inches long.
The length, strength, and thickness of the various external components of the weaver bird’s nest depend largely upon the building capacity of the male bird. As with male humanity, this varies greatly. Long after the female begins to sit, he may continue his task of nest-building. If he is possessed by the building urge, he strengthens the attachment of the structure to the tree above, adding more strands of fiber to and lengthening the rope that is already wound about the branch above.
The suspension cord is also increased in sustaining power by short fibers of palm or agave, plaited with strands already in position, and the walls of the nest chambers themselves are consolidated by similar material worked into their thickness. Meanwhile, the tubular entrance is extended, and the upper two-thirds of it are further strengthened.
When the young birds are first hatched, they are probably fed by the parents with food brought in by way of the long tube, but in some instances, at least, an opening is remade by the male bird from the outside directly into the egg chamber, and the fledglings are re-fed through these holes. One of the most fascinating habits of the Baya Weaver is the manner in which he enters and leaves the nest. I have watched the process many times and have always gazed in wonderment.
Even the so-called Chimney Swift entering his home may learn something from a bird that, apparently without agitating the shaky structure of his domicile, flies up to the narrow chimney-like structure and out again without hesitation. A male in the midst of repairing the roof suddenly take it into his head to visit his brooding wife. Flying or tumbling down the side of the nest, he spread his wings just in time to stop his fall a foot or two below the entrance. Apparently, without effort, he turned in midair and shot, like lightning, into the cylinder above him.
Some do not believe any other bird could have done it. Legge, who has wings at the moment of entering the tube, runs up it to the egg chamber. Be that as it may, Ploceus is secure in his home, for he is certainly the only animal that can fly, crawl, run, or creep up the smooth, fragile tube that leads to the interior of his nest. The nest is a firm, springy, and well-woven material that, when thoroughly dried, is used by the natives for filling mattresses.
Sometimes, during nest building, the Baya weaver brings in small lumps of wet clay, which they stick to a variety of parts of the interior of the nest and its walls. So, it found curious deposits in varying quantities in almost all the nests examined. One had about a tablespoonful of plastic mud deposited in three diverse localities, including one small patch in the egg chamber. On the other hand, a few had no mud deposits, and others had very little. Just what these clay deposits mean is by no means clear.
Indeed, none of the numerous explanations is satisfactory, especially rejecting the generally accepted theory that the mud is employed to balance the nest in the wind and to prevent it’s being blown about while tile birds are entering and leaving it, nor can I adopt Layard’s guess that tile birds use the clay as a sort of whetstone on which to sharpen their bills. In the first place, half a tablespoon of dried mud plastered midway through a large and long winging nest can have no influence whatsoever on its equilibrium in even a mild breeze.
Then again, many nests have no mud in their structure at all. Of course, the natives, as usual, have their own interpretation of the phenomenon—the bird uses the clay as a candlestick on which are stuck glowworms to lighten the darkness of the nest! Perhaps I may add another and, to my mind, more plausible theory: the habit is the survival in Ploceus of some ancestor who built his nest partly or entirely of clay.
The black clay deposits in Baya Weaver Nest then serve no useful purpose at all. They are just vestigial remains of a household economy, like the sleeve buttons on one’s coat! One is reminded of Stone, a similar example in the habits of birds completely unrelated to the weaver. But this genus is, in an evolutionary sense, flanked on the one hand by genera (Micropus, Taehornisw) whose nest material is partly mucus and partly other material, and on the other by genera whose nests have little or no mucoid matter in their makeup.
However that may be, our Weaver Bird is a highly intelligent animal, and whether one attributes his remarkable house-building to instinct, reason, or, as is most probable, a combination of these faculties, he makes a very attractive captive and an engaging presence in an aviary large enough to afford him plenty of room in which to build and breed.
He is, though, impatient with avian relatives and is very likely to quarrel with other birds placed with him on the same flight. T. B. Fletcher (Birds of an Indian Garden, 1924) tells us that among the natives of Punjab, a popular rhyme contrasts the helpless monkey with the resourceful house-building weaver.
In that, the former cannot protect himself from the weather in spite of his human hands and feet. This verse is quoted for the benefit of small boys and girls who object to learning, just as the busy bee is held up for infantile admiration of Western lands.”
Female P. p. philippinusSometimes, during nest building, the Baya weaver brings in small lumps of wet clay, which they stick to a variety of parts of the interior of the nest and its walls.The variety that builds the more elaborate nest is the Baya Weaver (Ploceusp. philippinus). The Baya Weaver Bird is also found all over the subcontinent, Java, and Sumatra.Male Baya Weaver philippinus displaying at nestNests hanging from palm (Phoenix sp.) fronds
