Blue Jay eggs vs Robin eggs: Discovering a small blue robin’s egg in the backyard was always a special find. These delicate half-shells were kept in a jewelry box lined with soft cotton. Robin’s eggs were likely the first bird eggs many learned to identify. Spotting one brings a bit of joy to the day for many.
Oftentimes, you can see an unrecognizable bird’s egg in your backyard. Is it a robin’s egg? The color might be right, but what about the speckles? Are robins the only bird that lay blue eggs?
Being able to differentiate between a blue jay eggs vs a robin eggs is a valuable skill. For bird enthusiasts, knowing more about the birds they love brings greater joy.
In this article we will delve into the differences between blue jay eggs vs robin eggs, after reading you’ll be able to differentiate between the two.
Blue Jay Eggs Vs Robin Eggs: Key Takeaways
| Difference In | Blue Jay Eggs | Robin Eggs |
|---|---|---|
| Appearance | Blueish or light brown, speckled with brown or gray spots, 1.0-1.3 inches long, 0.7-0.9 inches wide | Blue or blue-green, 0.8-1.0 inches long, 0.6-0.7 inches wide |
| Nesting | Trees, 10-25 feet above ground, Both parents build nest, 2-7 eggs, up to 18 days incubation | Trees, shrubs, or structures, 3-16 feet above ground, Female builds nest, 3-5 eggs, up to 14 days incubation |
| Incubation | Up to 18 days, Both parents share incubation, female does more | Up to 14 days, Both parents share incubation |
| Young | Leave nest 17-21 days after hatching, both parents feed them | Leave nest 13-15 days after hatching, both parents feed them |
| Interesting Facts | Build nests in evergreen trees, Occasionally use nests of other birds, Raid nests for eggs/nestlings | Nests made of mud and grass, Female incubates eggs for up to 14 days, Preyed upon by Blue Jays |
Also Check: Red Robin vs Cardinal
Robin Eggs: Everything You Need to Know
Due to the abundant population of American robins in North America, their eggs are also abundant. In the breeding season, a female robin will typically lays a clutch of 5-6 eggs, each slightly over an inch in length.
Since the female robin can lay eggs up to three times annually. It’s not surprising that robin’s eggs are often found scattered around beneath their nests.
Appearance Of Robin’s Egg
Robin’s eggs are consistently blue, but the shade can vary. The blue eggs can range from light to medium blue. Once in a while, they can be very light, almost white. And other times, the eggs may have small brown speckles.
Size of a Robin’s Egg
A robin’s egg is relatively petite, measuring between 1.1 inches to 1.2 inches (2.8-3 cm) in length and 0.8 inches (2.1 cm) in width. A useful point of reference for identifying robin’s eggs is that they are approximately the size of a quarter. They also weigh around 5.5 grams to 6.52 grams on average.
Nesting and Incubation Period Of Robin’s Egg
The female robin is solely responsible for incubating the eggs, which takes approximately 12-14 days. Once the eggs hatch, she clears the shells from the nest.
Both parents contribute to feeding the young, but the female takes on the major role. The fledglings typically leave the nest around 14-16 days after hatching.
Why are Robin’s Egg Blue?
The robin’s egg gets its blue color from biliverdin, a pigment that is distributed throughout the calcium carbonate shell during its formation in the shell gland of the female robin.
Research conducted at Queen’s University in 2012 revealed that higher levels of biliverdin are an indicator of a healthier female, resulting in brighter blue eggs. Eggs laid by healthier females appeared to get more help from the males in caring for the young.
The blue hue of robin eggs potentially serves a dual purpose, offering protection from harmful UV rays without excessive heat absorption. This balance is struck as blue is sufficiently dark to shield eggs from UV rays, yet light enough to prevent excessive heat retention.
Are Robins the Only Bird That Lays Blue Eggs?
No, Robins are not the only birds that lays blue eggs. Many other bird species also lay blue eggs.
Some other bird species that lays blue eggs includes; Blue Jays, Blue-footed Boobies, Western Bluebirds, a Starlings, Snowy Egrets, Red-winged Blackbirds, Dunnocks, House Finches, Common Mynas, Magpies, Emus, Great Tinamous, Blackbirds, Song Thrushes, Cassin’s Finches, and many more.
Many of the birds listed above, which lay blue eggs, can be found in North America. So, if you encounter blue eggs, there’s a possibility they may not belong to robins.
Blue Jay Eggs: Everything You a Need to Know
Being another common bird in the United States, Blue Jays are responsible for most of the blue eggs you may come across in grassy areas.
Compared to the Robins’ eggs, eggs from blue jay are a bit bigger, which aligns with the fact that adult blue jays are bigger than adult robins.
These eggs are typically seen below a blue jay nest, often constructed at the junction of a tree branch and its trunk.
Appearance of Blue Jay’s Eggs
Blue Jay eggs come in two possible colours, ranging from slightly bluish color to a light brown shade, and usually have light brownish or gray specks on them. Unlike robin’s eggs, Blue Jay’s eggs lack colour brilliance.
Size of Blue Jay’s Egg
The size similarity of robin and blue jay eggs is one issue that may lead to confusion. A blue jay’s egg is 1.0-1.3 inches long and 0.7-0.9 inches wide and is almost same size with a robin’s egg.
With only a 0.1-inch difference in both length and width, it can be difficult to differentiate the eggs from a Blue Jay and Robin when there is just a slight difference.
Nesting and Incubation Period Blue Jay’s Egg
The female Blue Jay lays from 2 to 7 eggs, which she then takes care of for up to 18 days. Both parents alternately incubate the eggs throughout incubation, however the female incubates the eggs for a longer period of time. The parents bring food for the nestlings when they hatch, and the fledglings leave the nest 17 to 21 days later.
Interesting Facts About Blue Jay’s Nests
Below are some interesting facts about blue jay nests on nesting location, size, and how they build it.
- Blue Jays are flexible when it comes to choosing their nesting spots. They will also use sites like the big mailboxes you would usually find in rural America if there isn’t a better spot, as in a highly deforested area.
- Blue Jays will make use of nests of other medium-sized songbirds provided they are built in the right spot; for instance, blue jays frequently use American robin nests.
- Both male and female Blue Jays gather the materials and build the nest, but on usually, the male does more gathering while the female does more building.
- Blue Jays will usually build their nests in the junction or sturdy outer branches of either coniferous or deciduous trees. Usually at elevations ranging from 10 to 25 feet above the ground.
- The outer portion of the blue jay nest is typically constructed using twigs sourced from live trees, and birds find it challenging to snap these twigs.
- Blue Jays prefer to build their nests in evergreen trees.
- The open cup nest that blue jays build is lined with rootlets and made with twigs, grass, and even mud.
- Blue Jay nests can measure up to 7 inches in diameter and 4 inches in depth.
What To Do When You See a Nest of Blue Jay or Robin Eggs
When you come across a bird’s nest with unhatched eggs, the best thing to do is leave it alone. The parent bird is likely close by, either getting food, fixing the nest, or taking a bath nearby.
Most birds wait until all the eggs are laid before they start sitting on them. So you might not see the parents around for a while. If you’ve been hanging around the nest, they might be waiting for you to go away before returning.
Prolonged absence from the nest can halt the development of the eggs or expose them to potential predators. To make sure the eggs remain at a suitable temperature for the growth and survival of the hatchlings, a bird needs to incubate them by sitting on them.
Even if the birds get scared and leave, they usually come back within a day or two. If the parents don’t return for an unusually long time, it could mean the eggs won’t hatch. But don’t remove the nest or eggs on your own. Instead, be patient and contact your local wildlife agency for guidance.