How Long Do Hummingbirds Sit on Their Eggs? The Delicate Balance of Incubation
The average incubation period for hummingbird eggs ranges from 14 to 16 days, but can vary depending on species, environmental conditions, and the individual mother hummingbird. This crucial period sees the female dedicate herself to maintaining the perfect temperature for successful hatching.
The Intricacies of Hummingbird Incubation
Hummingbird incubation is a remarkable feat of dedication and evolutionary adaptation. Understanding the process and the factors that influence it allows us to appreciate these tiny birds even more. The act of incubation is not simply sitting on the eggs; it is a finely tuned balancing act between maintaining optimal temperature and humidity, and occasionally leaving the nest to forage for essential sustenance.
Factors Influencing Incubation Time
Several factors contribute to the length of time a hummingbird sits on her eggs.
Species: Different hummingbird species may have slightly varying incubation periods. For instance, the Ruby-throated Hummingbird generally incubates for 12-14 days, while other species might take a day or two longer.
Temperature: Ambient temperature plays a vital role. Colder temperatures can prolong incubation, while warmer temperatures may slightly shorten it. However, extreme temperatures of either type can be detrimental.
Humidity: Optimal humidity is crucial for proper embryo development. Too little humidity can cause the eggs to dry out, while too much can hinder oxygen exchange.
Mother’s Age and Experience: A younger, first-time mother may not be as efficient at incubation as an experienced one, potentially leading to slightly longer incubation times.
Altitude: Hummingbirds at higher altitudes might experience longer incubation periods due to lower oxygen levels and cooler temperatures.
The Incubation Process: A Day in the Life
The female hummingbird assumes sole responsibility for incubation. Here’s a typical day for her:
Constant Vigilance: She spends the majority of her time sitting on the nest, meticulously arranging the eggs to ensure even heating.
Brief Foraging Flights: She takes short breaks to feed, usually lasting only a few minutes. These foraging trips are essential for her own survival and for the energy she’ll need to feed the hatchlings.
Nest Maintenance: She adds bits of down, lichen, and spider silk to the nest to keep it insulated and sturdy.
Egg Turning: Periodically, she turns the eggs to prevent the embryo from sticking to the shell.
Potential Problems During Incubation
Several issues can arise during incubation, threatening the survival of the chicks:
Predation: Nests are vulnerable to predators like snakes, birds, and insects.
Abandonment: If the mother is disturbed too frequently or faces a severe threat, she may abandon the nest.
Extreme Weather: Heavy rain, strong winds, or extreme temperatures can damage the nest or cause the eggs to cool down too much.
Infertile Eggs: Sometimes, an egg is simply infertile and will never hatch. The mother might continue to incubate it for a while before eventually abandoning it.
Table: Typical Incubation Times for Common Hummingbird Species
| Hummingbird Species | Average Incubation Time (Days) |
|---|---|
| Ruby-throated | 12-14 |
| Anna’s | 16-18 |
| Black-chinned | 16 |
| Rufous | 15-17 |
| Broad-tailed | 16 |
Frequently Asked Questions (FAQs)
How can I tell if a hummingbird egg is fertile?
It’s difficult to determine fertility from the outside of an egg. Experienced birders might “candle” the egg by shining a light through it after several days of incubation. Fertile eggs will show a network of veins, while infertile eggs will appear clear. However, disturbing the nest for candling is generally not recommended.
What happens if a hummingbird egg falls out of the nest?
Unfortunately, an egg that falls out of the nest rarely survives. The shock of the fall can damage the embryo, and the egg will quickly cool down, preventing further development. It’s best to leave it undisturbed.
What is the hummingbird nest made of?
Hummingbird nests are tiny masterpieces of engineering, typically constructed from:
- Plant Down: Soft plant fibers provide insulation.
- Lichen: Camouflages the nest and adds to its structure.
- Spider Silk: Used as a binder, providing elasticity and strength.
- Moss: Adds bulk and insulation.
How often does the mother hummingbird leave the nest to feed?
The frequency of foraging trips depends on factors like the availability of food and the stage of incubation. She usually leaves the nest for only a few minutes at a time, perhaps every 20-30 minutes during peak daylight hours.
What should I do if I find a hummingbird nest?
If you find a hummingbird nest, observe it from a distance and avoid disturbing it. Keep pets away from the area, and refrain from trimming vegetation around the nest until the young have fledged.
How long do hummingbird chicks stay in the nest after hatching?
Hummingbird chicks typically remain in the nest for approximately 3 weeks. During this time, the mother hummingbird feeds them regurgitated insects and nectar.
How can I attract hummingbirds to my yard so they might nest there?
Planting nectar-rich flowers and providing hummingbird feeders can attract these birds to your yard. Ensure the feeders are clean and filled with fresh sugar water (one part sugar to four parts water). Avoid using red dye, as it’s unnecessary and may be harmful.
Is it normal for a hummingbird nest to be empty sometimes?
Yes, it’s normal for the nest to be empty when the mother leaves to forage. However, if the nest is consistently empty for extended periods, it may indicate a problem.
What do hummingbird eggs look like?
Hummingbird eggs are tiny, oval, and pure white. They are about the size of a coffee bean.
Can I help a hummingbird mother by providing food near her nest?
Providing a constant source of nectar through feeders can certainly help reduce the distance she needs to travel to find food, potentially freeing her up to spend a bit more time incubating. However, it’s still best to minimize disturbance.
Do male hummingbirds help with incubation?
No, male hummingbirds do not participate in incubation or raising the young. The female is solely responsible for all nesting duties.
What is the biggest threat to hummingbird nests and eggs?
Predators, habitat loss, and pesticide use pose the greatest threats to hummingbird nests and eggs. Protecting natural habitats and avoiding pesticide use are crucial for the survival of these tiny birds.