[Tweeters] Fun with Robins
nwnature1 at gmail.com
Tue May 27 21:35:56 PDT 2014
Ok, so over the memorial day weekend while many of you were chasing down all
manner of exotic neato birds, I spent my time with Robins. My brother in
laws house outside of Selah is a horse place and he has 2 flat mowed acres
of lawn as the backyard. Up early on Sunday, coffee in hand I sat on the
back deck and watched Robins for quite a bit. Things got so interesting I
got out my watch and notebook to make notes on the patterns.
There were 19 robins all told, they were in two groups, and they all were
foraging. It was good hunting and it took an average of 2 minutes 35 seconds
for robins to get a worm. They would fly immediately to the southern border
hedgerow to feed their young. After a bit I noticed that some of the robins
were stealing worms from others and after a bit more time I realized that it
was only one robin that was doing the stealing and it had a very different
behavior pattern. In my notes I called the stealing robin the boss robin.
The foraging robins would scamper a few steps, stop, bend over, scamper
some more until they located a worm, then they would tug it out of the
ground, gather it up, then fly off with the worm to the nest. The boss robin
stayed upright, often flew in short hops to stay within close distance of a
group, and as soon as a forager started the tugging motion the boss robin
would fly over and displace the forager, grab the worm and fly off.
I got my bins and watched the southern group and sure enough I could find
the boss robin in that group by its behavior. At one point I got a very good
comparative look at the boss robin in the group closest to me and it was
bigger than the others. When the boss robin stole a worm and flew off the
foraging robins seemed to work a bit faster in its absence. And several
times if the foragers succeeded in getting the worm out of the group before
the boss arrived, they would fly away with it and the boss would sometimes
make a short chase but never very far.
At one point, the boss robin in the middle group landed close to the
southern group and the southern boss took off and there was a long, fast
chase with much scolding. Later several of the middle group foragers
drifted into the southern groups area and middle group boss robin changed
behavior and began foraging. This changed again when the density of foragers
increased to 6 birds.
Just before breakfast (mine) a Magpie flew in from the south and all the
birds but two flew into the hedgerow and began alarm calling. The magpie
landed in a tree and two robins very boldly flew at and made close passes at
the predator. I wondered if they were the boss robins?
Much later, after dinner, there were 5 fledglings foraging and one clearly
was not quite yet able to fly very well. Since my brother in laws cat was
on the prowl I cornered the little spotted guy, held him in the bird banders
grip and carried him over to the wood fence, intending to drop him over the
other side out of view of the cat. He began squawking his little head off
and two adults immediately flew over and began alarm calling. I stood a
couple minutes and 5 more adults joined in the alarm. I put the bird over
the fence, went in the house washed my hands and about 10 minutes later went
outside. Immediately several robins started alarm calling. Hmmmmm. More
fun. The Robins had not alarmed before. I went back inside took off my hat
and coat, as I returned, the alarm went off again. I put on a wig that my
sister in law had, and the robins still alarmed. Then I had my daughter go
outside and sure enough they alarmed at her, My wife, and my brother in law
were also alarmed at. So unlike Crows, apparently robins do not distinguish
between individual humans and that my messing with the fledging made all
humans a threat to warn others about.
Naturalist, Writer, Teacher
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