Scooter Watch

According to The Spruce.com Robin’s eggs are blue for a variety of reasons. Mainly it’s the pigment that is deposited in the shell or from the shell gland. “The shell gland is the avian equivalent of a mammal's uterus and is near the end of the oviduct, just before the cloaca. The shell is formed just before the egg is laid.”

Also, “The bile pigment biliverdin is responsible for blue tones in bird eggs. Depending on the concentration of the pigment, the coloration can range from bright, bold blue or blue-green to pale blue and every shade in between. Smaller eggs and those laid first in a brood are usually more intensely colored than larger eggs or those laid later in the nesting cycle.”

In addition to the biological reasons there is the camouflage issue to protect or disguise them from predators. Especially neutral tones but in the case of Robins they seem to be also protection from too much ultraviolet light so the developing baby will get the proper growth pattern.

“When an incubation period is strongly affected by heat from the sun, chicks are subject to greater mutations and higher fatalities because their development is rushed,” According the Spruce.com. In addition, “Health of Parent and Chicks: Brighter, more colorful eggs (within the proper colors for the species) are typically a sign of good health and a nutritious diet for the mother bird. Those hatchlings are more likely to be strong and healthy as well.”

Well, enough for today, happy bird watching.

Scooter