Hummingbirds, the smallest birds on earth, possess a remarkable biology, especially concerning their ability to hover and their intense metabolic rate. The female alone is responsible for constructing a safe nursery for her young, a feat of engineering that must be completed multiple times throughout the breeding season. Given the effort and precision involved, the question of whether these prolific builders revisit their meticulously crafted homes is common.
Nest Reusability: A Direct Answer
Hummingbirds generally do not reuse the same nest for subsequent broods, even within the same nesting season. This behavior is primarily related to the nest’s delicate structure and the survival of the young. The nest is designed to expand as the two nestlings grow, which permanently stretches and weakens its structural integrity by the time they fledge.
An old nest also accumulates waste and can become a target for predators or parasites once its location is compromised. Building a new nest in a different, well-hidden spot maximizes camouflage and minimizes the risk of attracting attention to the next clutch. While some species, like the Calliope or Scintillant hummingbird, have been observed building a new nest directly on top of an old one, this practice is the exception.
Construction: Materials and Structure
The tiny homes built by female hummingbirds are marvels of avian architecture, which explains why they lack durability for repeated use. The female collects soft, downy plant fibers, such as cottonwood or thistle down, to form the insulated cup of the nest. She then binds these materials together using strands of spider silk.
The silk acts as an elastic binding agent, securing the nest to the supporting branch and providing flexibility. This elasticity allows the nest to stretch outward, sometimes doubling its diameter, as the chicks grow. Finally, the exterior is often decorated with tiny pieces of lichen or moss, which are attached with more spider silk to camouflage the structure against the tree bark.
The Complete Nesting Cycle
The female hummingbird works entirely alone, as the male provides no assistance in nest construction or raising the young. Building the nest can take anywhere from a few days to a full week, depending on the availability of materials and the weather. Once complete, the female typically lays two pea-sized white eggs, spaced one or two days apart.
The incubation period usually lasts between 14 and 22 days, with the female spending most of her time sitting on the nest. The nestling period lasts approximately 18 to 30 days before the young birds are ready to fledge. The total duration from the first egg being laid to the chicks leaving the nest is often five to six weeks. Since females in favorable climates may raise two or three broods in a single season, they must construct a brand-new nest for each subsequent attempt.
What Happens to Old Nests
After the young hummingbirds have fledged, the nest is simply abandoned. The delicate, organic materials are subject to the elements. Without continuous maintenance, the nest begins to deteriorate quickly.
Wind, rain, and natural decomposition break down the plant fibers and moss. The stretched spider silk eventually loses its tensile strength, and the nest may fall apart within a few months. Occasionally, other tiny creatures, such as spiders or insects, may briefly utilize the empty cup for shelter. However, the fate of the majority of these intricate homes is to break down and return their materials to the environment.