Monday, June 01, 2009

Temperature-mid 80's
Skies-clear blindingly bright sunshine
Wind-light and variable

Primus on the right, standing, and Secundus down and left, staring, in their favorite positions

Primus preens. Secundus in comfy shadow stares. (What a surprise!)

Primus does a little hopping and flapping. Unfazed this is happening directly above his head, Secundus--well Secundus does what he does.

Wowie zowie. Still staring, Secundus stands up and actually exposes some body.

You may have noticed that we haven't seen the parents lately. They have gone back to their previous ways. Now that the eyasses are fed more at each feeding but less frequently. They wait to feed until after I leave.

Photograph by Amy of Illinois

What a lovely shot of a beautiful little nest full of new nestlings.

A female Robin having one ovary, lays one egg per day. She then waits to fully incubate until the clutch is complete. Therefore the nestlings hatch in a shorter time frame than one per day.

Amy says,
"Here is a picture of the baby robins :) that were born at my mom and Dad's' house this weekend - the mama built the nest in an 8 foot cherry blossom tree that is only about 8 or 9 years old - she built the nest right at the base of the branches, so we were able to peek in and check on the nest as it was at about eye level - the mama doesn't like us disturbing her, so we leave her be most of the time. Even my dog has been peeing by that tree which I believe is to mark his territory and ward off other unwanted creatures. When the mama flies away, the babies lift their head up like "feed me feed me."

(As is the case with many chicks, young Robins are cued to gape whenever there is a jar to the nest that is similar to an adult landing on the nest with food. Therefore an adult leaving the nest makes a vibration in pushing off for flight and that is why they gape when a parent leaves and when an adult lands with food as well.)

Amy's Robins made me remember that I hadn't taken more than five or so nest photographs of the Robins who have nested on the outside light next to the garage door so I got at it.

Likely the eldest chick is center. She seems to be the only one who is beginning to sprout real feathers. There are at least 4 fledglings possibly a fifth.

A nice brightly colored opening for food to be conveniently poked into. Each nestling will receive approximately 40 meals a day of soft invertebrates (earthworms, etc.), fruit, and plants.

Parental songbirds have been known to feed clever Koi Fish who raise their brightly colored and opened mouths out of the water as the parent birds go by. The cue is very strong.

Mama lands on the nest and checks out the nestling situation.

Then checks me out.

As far as I could tell, Mama had nothing in her beak when she landed. Therefore these fledglings are still in the stage where they are eating mostly parentally regurgitated food. Though earlier in the day I saw a worm coming out of the side of a parent's beak so a least one fledgling has gotten to the whole food stage.


Then back to whatever business she is engaged in.




Unfortunately I missed the shot but this time when Mom's head came up she was holding a fecal sac in her beak.
As nestlings defecate immediately after eating, and say 4 chicks at 40 poops a day, that's a goodly amount of feces. The babies would soon be up to their eyeballs in it without a disposal system. But the species has dealt with that issue by having the nestlings defecate in nice heavy white mucus "bags". When very young the bags contain very little bacteria and mostly consist of partially digested food. The parents eat these. As the nestlings get older and there is more bacteria in their digestive tracts, the parents pick up the fecal sacs in their beaks, fly a few suburban yards over and drop them. This is an anti-predator activity.

Heads flop back over the edge.

A tiny peek through slightly open eyes.

And back to snoozing until the next feeding.

Donegal Browne

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