Finches are small songbirds found throughout North and South America. They are known for their colorful plumage and melodious songs. Finches build cup-shaped nests and lay speckled eggs. Unfortunately, finch eggs often fall victim to predators. There are several animals that will steal and eat finch eggs if given the opportunity. Identifying what is stealing finch eggs can help birders better protect nesting finches.
Common Finch Egg Thieves
Here are some of the most likely culprits when it comes to stolen finch eggs:
Predator | Description |
---|---|
Snakes | Snakes like the black rat snake and garter snake raid nests and consume eggs. These sneaky predators can climb trees and shrubs to access nests. |
Blue Jays | Blue jays are opportunistic feeders that will eat eggs from nests of smaller songbirds like finches. |
Crows | Intelligent American crows sometimes plunder nests for the protein-rich eggs inside. |
Squirrels | Squirrels often steal eggs from open cup nests. They are adept climbers and can access nests in trees. |
Raccoons | Nocturnal raccoons locate nests and will readily eat eggs. They have very dexterous paws for grabbing eggs. |
Opossums | Opossums raid nests at night. They eat eggs and also prey on nestlings. |
Foxes | Foxes climb trees and bushes looking for bird nests. They consume the eggs and may also kill adult birds. |
Feral Cats | Roaming domestic cats hunt and kill adult birds. They also loot nests for eggs. |
Other Potential Finch Egg Thieves
In addition to the most common finch egg predators listed above, there are some other animals that may also occasionally take finch eggs, such as:
– Chipmunks
– Weasels
– Rats
– Magpies
– Bears
– Coyotes
– Feral dogs
– Skunks
The diversity of animals that eat finch eggs demonstrates that many different types of predators will take advantage of this tasty, protein-rich food source if given the opportunity.
How Do Predators Find Finch Nests?
Predators employ a variety of techniques to locate hidden finch nests to steal the eggs.
Keen Vision
Many animals like crows and jays have excellent eyesight and meticulously scan their surroundings for any sign of nests. Even the slight movement of an adult finch going to or from a nest can attract their attention. Once a nest is spotted, they remember the location to return and raid it.
Alert Hearing
Snakes have very sensitive hearing and can detect faint noises coming from nests such as adult finches chirping while incubating eggs. This alerts snakes to investigate potential nesting sites.
Deductive Reasoning
Intelligent predators like crows understand finch behavior patterns. So they closely observe where adult finches fly to and from and can deduce the probable locations of nests.
Random Searching
For predators like squirrels and raccoons, finding nests often involves randomly searching likely finch nesting spots in trees and bushes until they locate a nest. Their nimble climbing abilities give them access.
Sense of Smell
Foxes and other predators that hunt more by scent use their keen sense of smell to find concealed nests. Even if they can’t see or hear a nest, the scent gives away the location.
Clever Finch Egg Hiding Strategies
Finches have evolved some clever adaptations to conceal their eggs and hide nests from predators:
Camouflaged Nests
Finch nests are built from materials like twigs, grass, moss, and lichen chosen to blend in seamlessly with the surrounding environment. This helps conceal nests from visual predators.
Inconspicuous Locations
Finches prefer to nest in hidden spots like dense shrubs, inside foliage clumps on tree branches, and within dense vines. These secluded sites reduce the chances of predators stumbling upon the nest.
Cryptic Egg Markings
The speckled, mottled patterns on finch eggs serve as camouflage when the adult finch is away from the nest. This makes the eggs harder to spot by predators.
Secretive Behavior
Adult finches try to visit and leave the nest as quickly and quietly as possible. They approach the nest from varying directions to avoid creating a predictable trail. This decreases activity cues that could lead predators to the nest.
Defensive Displays
If adult finches spot a predator approaching the nest they may perform distraction displays to draw it away. This includes faking a broken wing or calling loudly while moving away from the nest.
Clever Predator Tricks
Predators have some counter-strategies to circumvent finch nest defenses:
Stakeouts
Intelligent predators like crows sometimes simply watch prime nesting sites patiently waiting for finches to give away the position of their nest by their movements. Once the nest is identified they return when the adult finches are away.
Mobbing
Some predators incite mobs of birds by appearing near nest sites. When the adult finches join other birds to drive the intruder away, the predator pinpoints the nest location by watching the adult finches.
Distraction
Predators like squirrels and jays sometimes create a distraction to draw adult finches away from the nest, such as by appearing on the opposite side of the nest tree and calling loudly or even dropping sticks on the ground to draw the finches away to investigate the sound. This gives the predator access to the nest.
Ruthlessness
Predators like snakes and raccoons reach into nests and eat eggs immediately with no hesitation. Their lightning quick strikes give finches little time to mount a defense.
How Predation Impacts Finches
Losing eggs to frequent nest predation can significantly impact finch breeding success and populations. Some of the notable effects include:
Lower Numbers
Each stolen finch egg represents a lost future finch. Heavy nest losses can lead to declining finch numbers in areas with high densities of aggressive nest predators.
Stressed Adults
Adult finches who experience repeated nest failures from predation may become stressed and desperate. This can impair their future nesting behaviors and abilities to raise young.
Reduced Genetic Diversity
Predators often target the most visible nest sites. So finches that nest in more concealed locations tend to contribute more to future generations. This can reduce genetic diversity over time.
Delayed Breeding
After nest predation, finches must rebuild a nest and lay a new clutch of eggs. This delays breeding by two weeks or more, limiting time to successfully raise multiple broods within a single breeding season.
Abandoned Territory
Some finches may permanently abandon prime nesting territories after suffering repeated nest losses. This forces them to move to potentially less suitable habitat.
Population Declines
Sustained high rates of nest failure coupled with other factors like habitat loss can ultimately lead to dwindling finch populations. Several finch species are classified as threatened due to declining numbers caused in part by nest predation.
Deterring Finch Egg Predators
Birders and property owners can take various steps to deter predators and protect vulnerable finch nests:
Remove Attractants
Eliminate food sources like open trash cans and fallen fruit that attract predators like raccoons and opossums to the area. Fewer predators nearby reduces nest interference.
Use Predator Guards
Wrap sheet metal, plastic pipes, or prickly branches around tree trunks and posts near nests to obstruct climbing by squirrels, snakes, and other predators.
Install Baffles
Place cone-shaped plastic or metal baffles on poles and fence posts to block predators like raccoons from being able to climb up.
Apply Repellents
Spray or rub nests and nearby branches with hot sauce, black pepper oil, or predator urine. The strong scents can deter curious predators. Reapply regularly.
Add Protective Netting
Stretch fine plastic netting tightly around nest trees or shrubs to create a protective barrier against predators. Just be sure netting does not obstruct the adult finches entering and exiting the nest.
Situate Nest Boxes
Mount nest boxes on long metal poles at least 6 feet off the ground with a predator guard below. This helps protect the nest from most climbing predators.
Use Fake Eggs
Temporarily remove real finch eggs and replace with convincing fake eggs. This causes predators to leave the nest alone after investigating and finding no reward. Then return the real eggs.
Control Local Predators
Use legal predator traps or work with animal control to humanely reduce very high populations of problematic nest predators like raccoons and feral cats in the immediate area around finch nesting sites.
Conclusion
A diversity of opportunistic predators like snakes, jays, squirrels, crows, and raccoons pose a constant threat to finch eggs. These crafty nest raiders employ various tricks to locate and steal eggs. Heavy nest predation can severely impact finch breeding success and populations. But birders can take proactive steps to deter nest predators and increase the chances that finch eggs remain safely tucked away in their cleverly concealed nests. Protecting finches from excessive egg predation is important to ensuring abundant and diverse finch populations.