Lethbridge Naturalist’s Society

Nesting Season is Here

Did You Know?

Photos by C. Burstlein

The American Robin (Turdus migratorius) female chooses the nest site and builds the nest. An average of 180 trips a day, with mud or grass is necessary to finish the nest in two to six days. In southern Canada, the first clutch, or set of eggs, is laid in late April or early May. Why are American Robin’s eggs blue? The blue colour is due to biliverdin, a pigment deposited on the eggshell.

Did You Know?

Higher biliverdin levels indicate a healthier female and brighter blue eggs. Eggs laid by a healthier female seemed to encourage males to take more interest in their young. Nestlings fledge their nest at approximately 13 days old. The American Robin has an extendible esophagus. This can be useful in winter, when the bird may store fruits in the esophagus before it settles for the night. This probably allows the robin to survive low nighttime temperatures.

For more information:

https://www.audubon.org/ field-guide/bird/americanrobin https://www.allaboutbirds. org/guide/American_Robin https://www.hww.ca/en/ wildlife/birds/americanrobin.html https://calgaryherald.com/ news/localnews/american-robin-flies3220-kilometres-fromalberta-to-breed-in-alaska https://cwffcf.org/en/search.jsp?quer y=american+robin&folderI D=364079081&includeSub folders=true

Information about upcoming Nature Walks:

www.NatureLethbridge.ca