Carolyn’s Online Magazine (#COMe)
HOW DO ROBINS GROW FROM EGG TO FLIGHT?
Part 3: Quiz #2
On May 1st I noticed a nest, tucked behind a light on our patio, in which were four gorgeous blue eggs. We were about to take an unplanned journey with Mom Robin, who was incubating her eggs.
This is the third of four posts—an introduction (How Do Robins Grow From Egg to Flight?: Part 1) and three 10-question quizzes (each with a bonus question) on robins, illustrated with photographs I shot daily to record the chick’s progress and the care they received from Mom Robin and Dad Robin. (How Do Robins Grow From Egg to Flight?: Part 2 )
Below is the second quiz.
11. What happens if you move a robin’s nest?
12. How long does it take for robin eggs to hatch?
13. How much do newly-hatched robins weigh?
14. Describe newly-hatched robin chicks.
15. How do robin chicks recognize their parents?
16. How often do robin chicks eat?
17. How do robin chicks keep their nest clean?
18. Robins are altricial birds, meaning what?
19. What are the main predators of robin eggs?
20. If one parent is killed while the robin eggs are incubating the eggs are incubating, will the other parent take over the nest?
Bonus question What three things does a baby robin know as soon as it hatches?
To learn the answers click on more:
11. As Mom Robin builds her nest she memorizes all the features around it. Moving the nest makes the environment of the nest different. When those features are gone because the nest is moved, she may simply not even recognize her nest anymore.#
12. Robin eggs hatch 12-14 days from the time the last egg is laid.** Mom Robin broods on the nest in order to keep the babies warm.^^^
13. Newly-hatched robin chicks weigh 5.5 grams–a little less than a quarter.**
14. Baby robins are colorful—their skin in bright light may appear yellowish, and is transparent enough to see their green gall bladder, purplish-red liver, and orange yolk sac right. The inside of their mouths is bright yellow and orange-red. **
15. When robin chicks first hatch they probably don’t recognize their parents. However, they know when the parents arrive with food by the “bounce” they feel on the nest, which is their signal to pop up with their mouths open. Gradually they start learning the sounds their parents make. By the time their eyes open they recognize their parents’ voices.**
16. Both Mom Robin and Dad Robin spend literally every waking hour gathering food for them. The parents return to the nest every few minutes all day long, from sunrise to sunset.#
17. Robin chicks produce their poop in fecal sacs, encased in strong membranes that don’t leak.** (My observation: these sacs are white. After the chicks expel them either Mom Robin or Dad Robin discard them from the nest.)
18. Altricial means that robin chicks are hatched in an immature state and depend on care from their parents to survive.^^
19. The main predators of robin eggs are snakes, squirrels, blue jays, and crows. Snakes swallow eggs on the spot. Squirrels usually stay up in branches, and seldom drop their eggs Jays and crows are both egg and nestling eaters.#
20. If Mom Robin is killed the eggs are doomed because Dad Robin lacks a brood patch, so he doesn’t know how to brood eggs. If Dad Robin dies Mom Robin might continue to incubate, but may just give the nest because her chances of being able to feed more than one or two nestlings is very slight.#
BONUS QUESTION ANSWER:
The nestling knows
- to sit very still when its parents are away
- to pop up and open its mouth to beg for food the moment its parents return
- and to poop as soon as it swallows some food.**