Do hummingbirds make their nests out of spiderwebs?

Hummingbirds are amazing little birds that have captured the fascination of people for centuries. Their incredibly fast wingbeats, their ability to hover and fly backwards, and their beautiful iridescent feathers make them a joy to watch. Hummingbirds are also known for making intricate, cup-shaped nests to hold their eggs and raise their young.

Given their small size and the delicate nature of their nests, a common myth has emerged that hummingbirds actually build their nests out of spiderwebs. This myth likely started because hummingbird nests and spiderwebs share some similar characteristics – they are both intricate, have some stretch or give to them, and are made of thin strands bound together. However, the materials hummingbirds use to build their nests are very different from spider silk.

What do hummingbird nests look like?

Hummingbird nests are tiny, cup-shaped structures roughly 2-3 inches across. They have thin, flexible walls made of plant fibers, spider and insect silk, moss, lichen, and even feathers. The inside of the nest is lined with soft plant down and sometimes bud scales to cushion the eggs.

Nests are precision-engineered to be stretchy enough to accommodate the growing chicks, but not so elastic that they lose their shape and dump the young birds out. They are engineered to cling to and conform around the support structures where female hummingbirds choose to build them, like branches, poles, eaves, or dessert cacti.

Where do hummingbirds build their nests?

Hummingbird nest placement depends on the species, but they are most commonly found in trees and shrubs. Some species like Anna’s and Allen’s hummingbirds readily use human-made structures like porch railings, exterior light fixtures, and hanging baskets as nest sites. Other uncommon but preferred nest locations can include: cacti, vines, ferns, moss-covered rocks, fallen logs, roots, and even on the ground.

Whatever the location, the nests are well-camouflaged and often difficult for humans to spot. Female hummingbirds look for sites that will protect the nest from predators and the elements. Nest height can range from just a couple feet off the ground to over 100 feet in trees.

When and how do hummingbirds build nests?

Hummingbird nest construction happens between late winter and early spring depending on the climate. In most species it is only the female that builds the nest over 6-12 days leading up to egg laying. She uses spider and insect silk to tightly bind plant down, fibers, lichen, and moss together, forming the tiny structural walls.

Building happens in short bursts, with the female leaving periodically to gather more materials until the egg-cup shape is complete. The inside is then lined with soft cotton-like plant down, feathers, or other cozy materials. Males do not assist with nest building or rearing the chicks in most hummingbird species.

Do hummingbirds use spiderwebs to build nests?

While hummingbird nests often look delicately woven like spiderwebs, they are not actually constructed from spider silk. Here are some reasons hummingbirds do not use spiderwebs to build their nests:

• Spider silk alone lacks the stretch and flexibility that is ideal for allowing the nest to expand as the chicks grow. Hummingbird nests need to be elastic, but also maintain their structural integrity.
• Spider silk is designed for capturing prey. It would be too sticky and inelastic to facilitate easy entry and exit for the female hummingbird as she incubates her eggs and feeds the chicks.
• Spider silk takes a huge amount of energy for spiders to produce, so it would not be efficient for spiders to make enough silk to donate their webs to hummingbird nest construction.
• Spiderwebs are designed in a flat sheet web pattern that provides no pre-shaped cup structure. The female hummingbird would have to rework the fibers extensively.
• Hummingbird nests are engineered to cling to a support structure from all angles and surround it. Spiderwebs radiate out vertically from a central point and lack the same elasticity all around.

So while spider silk might contribute some threads to strengthen the outer walls, hummingbirds cannot rely on it alone to create a viable nest. The bulk of hummingbird nest materials come from plant fibers, moss, lichens, feathers, and bud scales collected by the female.

What materials do hummingbirds use for nest building?

Here are the most common natural materials used by hummingbirds to construct their tiny nests:

• Plant down – The soft, cotton-like fibers from plants like thistles, cattails, and milkweed. Used to line the interior and provide padding for eggs and chicks.
• Spider silk – Used sparingly, but helps bind the nest materials together for durability. Collected as strands left behind on surfaces.
• Plant fibers – Flexible fibers from stems, leaves, bark, roots, ferns, and other plants to form the sides of the nest walls.
• Moss and lichen – Soft fibers collected from trees, rocks, and logs. Used in the nest sides for stretch and insulation.
• Feathers – Occasionally woven into the outer nest walls or used for interior lining. Provide insulation.
• Bud scales – Tightly overlapping scales from flower buds. Used in lining for padding and cup shape.

Hummingbird nests are a marvel of precision avian engineering using select natural plant and insect materials. The exact combination of stretchy yet strong fibers Allows the tiny nests to permanently adapt as the chicks grow, while still maintaining their basket shape.

How do hummingbirds weave the materials together?

Hummingbird nests may appear haphazardly assembled to our eyes, but they are crafted through a careful process by the female bird:

1. She collects soft plant down for the interior lining by delicately plucking and gathering the fibers with her beak.
2. Small pieces of flexible bark, fern fibers, lichens, and leaves are gathered next for the exterior walls.
3. The female hummingbird uses spider silk like twine to tightly wrap and bind the materials together in a methodical weaving pattern.
4. She skillfully shapes and molds the fibers into a tiny cup with her body as she works. The cup rim takes shape first.
5. More soft lining materials get added and pressed into shape by her body to complete the interior.
6. The female securely attaches the finished nest to a support structure by binding it tightly with strands of spider silk.

The female hummingbird has specialized feet with tendons that allow her to dangle from supports and carefully weave the nest while hanging upside down. This allows her to shape the nest as she binds the materials together into a cozy, durable cup perfect for her eggs.

How do hummingbird nests attach to surfaces?

In a final step of nest construction, female hummingbirds use spider silk like adhesive to bind their nests to the support structures they are built upon. Some techniques hummingbirds use include:

• Tightly wrapping spider silk strands around small branches dozens of times to firmly fix nests to trees and shrubs.
• Trailing loose ends of silk that adhere to surfaces like glue, attaching nests to man-made structures.
• Weaving silk strands into the outer nest walls during construction for permanent adhesion.
• Spearing thick wads of silk through gaps in materials for anchoring. Often used to affix nests to poles and fences.

This adhesion technique using sticky spider silk provides safety from predators and keeps the nests stabilized in wind and rain. The female can even adjust anchoring points by adding more silk as the nests shift from the growing chicks inside.

Do hummingbirds reuse their nests?

In most species, hummingbird nests are built new each breeding season and are not reused for a second clutch of eggs. Some reasons hummingbird nests are single-use include:

• They may be damaged by weather exposure through the seasons when not in use.
• Younger chicks can tear the nest lining and walls as they grow.
• Parasites and insects can infest the old nest materials, posing a threat to new eggs.
• Rebuilding each season allows improvements in ventilation, insulation, and structure.
• A new nest helps attract a mate, signaling the female’s fitness to breed.

However, a few hummingbird species such as Anna’s hummingbirds have been observed reusing a nest for a second clutch on rare occasions. In most cases though, hummingbirds find a new site and build a brand new nest each breeding season.

Conclusion

Hummingbird nests are engineering marvels of precision and flexibility, crafted by the female bird from plant fibers, spider silk, and soft lining materials. While their delicate appearance resembles spun spiderwebs, hummingbird nest construction does not use actual spiderwebs which lack the right combination of elasticity and shape.

The rumor that hummingbirds build their nests from spiderwebs likely started simply because of the similarities seen in intricacy and weaving pattern. On closer inspection though, it becomes clear their tiny nests are assembled using a specialized combination of plant-based materials purposefully shaped into a cozy, durable cup design capable of stretching to accommodate the growing chicks inside.