Empty Robin's Nest - Turdus migratorius
On June 19. 2013, I saw a Robin's nest in the rafter of the shelter at the Elbow River Constructed Wetland site. There were two eggs in the nest. I monitored the nest and noted 4 eggs on June 21 and 5 eggs on June 29. Likely the mother laid a single egg each day on June 20, 21, 22, 23, and 24. There are usually an average of 4 eggs with a range of 3 to 5.
I was away from home for over a week and did not check the nest again until July 13, by which time the eggs had hatched and there were two chicks. I saw two chicks again on July 14 and July 16. The usual incubation period is 11 to 14 days. On July 13, the chicks looked large enough to be at least a week old.
On July 24 the nest was empty. Robin chicks usually leave the nest 14 to 16 days after hatching.
If the incubation range (11 to 14 days) is added to the time-to-fledge range (14 to 16 days), a chick might fledge as early as 25 days or as late as 30 days after the egg is laid.
Based on my observations and the math, the two chicks who hopefully fledged, could have been from any one of the five eggs.
I never tried to take photos of either the eggs or the chicks. The mother always flew off when I entered the shelter and I only permitted myself a quick glimpse at the nest contents.
The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.
Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.
Sibley David A. The Sibley Guide to Bird Life and Behavior. Alfred A Knopf, Inc. New York. 2001.
On June 19. 2013, I saw a Robin's nest in the rafter of the shelter at the Elbow River Constructed Wetland site. There were two eggs in the nest. I monitored the nest and noted 4 eggs on June 21 and 5 eggs on June 29. Likely the mother laid a single egg each day on June 20, 21, 22, 23, and 24. There are usually an average of 4 eggs with a range of 3 to 5.
I was away from home for over a week and did not check the nest again until July 13, by which time the eggs had hatched and there were two chicks. I saw two chicks again on July 14 and July 16. The usual incubation period is 11 to 14 days. On July 13, the chicks looked large enough to be at least a week old.
On July 24 the nest was empty. Robin chicks usually leave the nest 14 to 16 days after hatching.
If the incubation range (11 to 14 days) is added to the time-to-fledge range (14 to 16 days), a chick might fledge as early as 25 days or as late as 30 days after the egg is laid.
Based on my observations and the math, the two chicks who hopefully fledged, could have been from any one of the five eggs.
I never tried to take photos of either the eggs or the chicks. The mother always flew off when I entered the shelter and I only permitted myself a quick glimpse at the nest contents.
References
The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.
Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.
Sibley David A. The Sibley Guide to Bird Life and Behavior. Alfred A Knopf, Inc. New York. 2001.
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