Spectacular architectural undertakings of the tiny weaver

For most birds in this region, the busy period of raising a family is over. The juveniles have acquired from their parents the life skills needed for survival and are ready to lead independent lives.

Not for the weaverbirds though. While many may not be able to identify weaverbirds on sight but their retort-shaped nests, hanging high up on a palm tree or from the branches of a thorny acacia, are a familiar sight. The intricate knotting and weaving of grasses and the unique shape captures the attention of even a casual passerby. Their unique style of building their nests has inspired humans in their architectural pursuits.

The monsoon rain brings with it new life. Trees and grass grow with renewed vigour. Weaverbirds use these fresh green fronds and grasses to weave their nests, which will house the next generation. Of the 115 species of these little birds found in the world, four are present in India. Three of these species — Streaked Weaver, Black-Breasted Weaver and Baya Weaver — can be seen around Chandigarh. Not more than 15 cm in size, these species may differ slightly in appearance, but they all share the remarkable ability to weave unique and intricate nests.

The Streaked Weaver and the Black-Breasted Weaver are more elusive as they choose to build their nests in tall reeds of marshy areas, where they remain well-hidden. In these species, the females help the male in adding finishing touches to the interior of the nest, making sure that it is perfect for raising a brood.

The Baya Weaver, however, is the most well-known of the trio. Its nest colonies are usually in full public view. For anyone in Punjab, village and town dwellers alike, the nests of weaver birds have been a familiar sight since childhood. Colonies of these nests can be seen waving in the breeze on Babool trees surrounding the village pond or on tall palm trees in city parks in Punjab.

The male Baya constructs the nest in stages, beginning by securely attaching it to a sturdy branch. With his beak and claws, he painstakingly starts to make the rounded globe shape by knotting and weaving thin strands of grasses. It is probably the only bird species that has the ability to make knots.

Once the initial structure is complete, the males invite the females to inspect their architectural skill — a sort of debutantes’ ball where the nest, rather than the males’ physical appearance, is the primary criterion of selection. Unlike most species where the males are chosen based on health and plumage, the weaverbirds’ females choose their mates based on the quality of the nest.

The nest-building skills, the location chosen for the nest, the material used and the durability of the design are all critical to her decision.

The male’s uncertainty is palpable as he perches nearby, fluttering and twittering nervously, while the female inspects his craftsmanship with a fine tooth comb — looking for even the slightest hint of tardiness. Only after passing this rigorous inspection does the female accept his amorous advances.

Once approved, the male must finish the nest quickly. He completes the egg chamber located in the globular section of the nest. Mindful of the needs of his lady love, he lines it with soft material to protect the eggs, unlike the strong grasses which he had chosen for their durability to build the outer structure. In the final stage, the tubular passage is constructed as protection against predators.

Village houses traditionally use a mixture of clay and cow dung for insulation against heat and cold. Bayas also use clay and cow dung to line the inner part of the nest around the egg chamber, possibly for structural strength and insulation. A belief that the birds stick fireflies to the mud to light up their nests, though a romantic notion, lacks any scientific backing.

Rejection is an accepted fact for the male Baya. A failed nest means starting from scratch and a single male may have to build several nests before he can successfully impress a mate. These rejected abodes hang as silent testimonies to not only his many failures, but also to his perseverance and dedication to perfecting his technique.

The Bayas inspire us to learn from their tenacity and perseverance against all odds. The challenges of protecting themselves from natural predators and the elements of nature are nothing compared to the devastation caused by human activities. The trees and grasses, which are an essential sources of nesting sites and material, are blatantly destroyed in the name of progress. In a few instances, Baya nests have been recorded hanging from even high tension electric wires!

Perseverance in the face of adversity — an inspiring lesson from a tiny bird.

— The writer is president of the Chandigarh Bird Club