What are the reasons a bird might abandon its eggs?
There are a few reasons why a mother bird may abandon her eggs:
- The eggs are not fertilized. Unfertilized eggs will not hatch, so the mother bird may abandon them.
- The habitat is no longer suitable. If the nest site becomes compromised by weather, predators, or human interference, the mother may abandon it.
- The mother is killed or dies unexpectedly. Obviously if something happens to the mother bird, she can’t continue incubating.
- The eggs are infertile. Even fertilized eggs may fail to develop properly. The mother bird can sense this and abandon them.
- Stress or disturbance. Excessive noise, activity, or harassment near the nest may cause the mother to desert it.
- Lack of resources. If food and water sources run low, a mother bird may be unable to produce enough body heat and energy to incubate eggs.
- First-time breeders. Inexperienced mother birds sometimes make mistakes or lack strong nesting instincts.
- Predator threats. To protect herself, a mother bird may flee the nest if predators are too close by.
In most cases, the decision to abandon a nest is outside of the mother bird’s control. Their instinct is to incubate eggs, so they will only leave them if forced to. Predation, lack of resources, and human interference are common reasons.
What should you do if you find abandoned bird eggs?
If you discover abandoned bird eggs that the mother is not returning to, here are some recommendations:
- Leave the eggs alone if possible. The parents may return, or the eggs may be close to hatching. Moving or touching them risks damaging the embryos.
- Check for signs of distress. Cool eggs or nestlings chirping loudly indicate abandonment. Eggs that look cracked, leaking, or have dead nestlings need removal.
- Warm the eggs immediately if abandoned. Use your hands, a heating pad, or incubator to stabilize the temperature.
- Create a makeshift nest. Place the eggs in a small basket, padded with tissues or cloth. Hang it near the original nest site if possible.
- Contact a wildlife rehabilitator. Licensed specialists have the best resources to incubate eggs and hand-raise hatchlings.
- Do not attempt to hatch eggs at home. Proper technique, humidity, and temperature control are needed, which is extremely difficult to provide.
- Carefully monitor hatching eggs. Newly hatched songbirds need feeding every 15-20 minutes from dawn to dusk.
- Release nestlings once fledged. Let a rehabilitator guide you on when the babies are ready to leave the nest and survive on their own.
With quick action, abandoned eggs can sometimes be saved. But the best option is always to reach out to qualified wildlife experts, who will give the hatchlings their best chance.
What are the signs that a bird has abandoned her eggs?
Here are some clear signs that a mother bird has left her eggs for good:
- The eggs feel cold to the touch
- The eggs remain unattended for several hours
- The mother is not seen going to the nest for 2 days or more
- The eggs are intact but have not hatched past the normal incubation time
- Broken egg shells are found below or near the nest
- Nestlings are crying loudly from hunger or distress
- The nest looks disturbed or damaged
- The eggs are on the ground instead of in the nest
The key is observing that the mother bird is no longer sitting on the eggs to provide warmth and protection. Cold, exposed eggs that are not being turned by the parent are in jeopardy and need intervention. Listen for hungry cries from nestlings, which indicate abandonment. Damaged or discarded eggs are a clear sign the nest has been deserted.
How long can abandoned bird eggs survive unattended?
Bird eggs can only survive a short time once the parent bird stops incubating them. The exact timeframe depends on the species and environmental conditions:
- Finch or sparrow eggs – 6 to 12 hours unattended
- Robin eggs – 24 hours at most
- Wren or bluebird eggs – 48 hours if temperatures stay mild
- Duck or goose eggs – May survive 72 hours in cool weather
- Raptor or crow eggs – Up to 96 hours due to thicker shells
The warmer the ambient temperature, the faster abandoned eggs will cool and the embryos inside will die. Eggs of tropical species have the shortest survival time. Small songbird eggs are at high risk as they cool rapidly. Thick shells of ducks, geese, and raptors retain more heat. But all abandoned eggs need rescue within several days at most.
Can you incubate abandoned bird eggs at home?
It is technically possible but extremely difficult to incubate rescued bird eggs at home. Proper temperature and humidity levels must be maintained constantly to hatch abandoned eggs:
- The ideal incubation temperature is 99.5-100 F for most songbirds
- Humidity should be 40-50% in the incubator
- Eggs must be turned gently at least 3 times per day
- Hatchlings have high feeding and care requirements every 20 minutes
For success, the proper incubator or brooder setup with gauges and adjustments is needed. Specific knowledge of each bird species’ requirements is also key. Furthermore, hand-feeding hatchlings around the clock is demanding. For these reasons, it is best to contact an avian rescue or rehabilitator to take in abandoned eggs rather than trying to incubate them yourself at home.
What should you feed baby birds hatched from abandoned eggs?
If you end up with hatchlings from rescued abandoned eggs, here are some emergency feeding options:
- Commercial hand-feeding formula for baby birds (best option)
- Pureed dog or cat food mixed with vitamins
- Baby bird “bread” mix of ingredients
- Pureed insects, seeds, fruits and vegetables
- Small pieces of hard boiled egg yolk
- Ground up dry dog kibble or soaked kibble
The ideal food for orphaned hatchlings is a powdered hand-raising formula made specifically for the bird species. Only use commercial formulas made for birds, not formula made for other animals. In an emergency, pureed high-protein cat or dog food can provide nutrition. Mixing in a powdered vitamin supplement is critical. A rehabilitator can advise you on improvising proper hand-feeding diets if needed. Proper feeding technique is also vital so the babies do not inhale food into their lungs.
Can you return baby birds to the nest after rescuing eggs?
If orphaned baby birds hatch after you’ve rescued abandoned eggs, returning them to the original nest is an option in some cases:
- Only if the nest is 100% intact and weatherproof
- If no signs of predators, parasites, or parents are found
- For altricial species that leave nest at 2-3 weeks old
- If babies are placed back before getting cold or hungry
The goal is to restore the babies quickly before the parents return and find them missing. The nest must still be fully functional and safe from threats. Altricial birds like robins, wrens, or chickadees are the best candidates for renesting if they are returned quickly. Precocial species like ducks cannot be returned once imprinted. A wildlife rehabilitator can advise you on the feasibility of putting orphaned babies back based on timing and factors like species, age, health, and habitat.
Conclusion
Discovering an abandoned bird’s nest with eggs is a situation that requires careful action. While the natural instinct is to try and save them, it is extremely difficult to incubate eggs properly at home without the right training and equipment. In most cases, the best chance for the eggs’ survival comes from immediately contacting an avian wildlife rehabilitator or rescue organization. They have the skills and resources to incubate eggs, feed hatchlings, and potentially return nestlings to the wild if circumstances allow. With quick thinking and the help of experts, it is possible to intervene and give abandoned eggs and babies the care they need.