Wren Feeding Frenzy
Our local wrens have successfully raised a brood and moved on. While
we find that we miss the daily chatter (well, maybe not the endless
wren-song beginning at dawn just outside our bedroom window!), we
don’t necessarily miss having them curse us, berate us, and call our
parentage into question every time we passed their chicks on the way
to our mail box or to pick up the morning newspaper.
But here are some notes regarding the wren feeding frenzy in the week
before the chicks fledged.
I timed them in randomly chosen 15 minute periods throughout the past
week to measure frequency of feeding behavior. The wren parents
delivered insects to the nest box at an average of once per minute --
low count, 13 times; high count, 21 times -- during each of those 15
minute sessions.
Extrapolating those numbers: roughly 60 visits per hour; and, since
they were observed feeding from approximately 7:00 a.m. to 7:00 p.m.,
that would be 60 x 12 hours per day = 720 visits per day or an
astounding 5,040 visits per week.
According to The Birder’s Handbook, House Wrens incubate for 13 days,
and then the chicks fledge in 12-18 days during which time the
parents would be gathering insects to feed hungry chicks. So, the
grand total in those 12-18 days would be 8,640 to 12,960 number of
visits to the nest.
Of course, while observing them, they did take off time when it was
night or when it rained. Or, to attack a gray squirrel who innocently
lumbered by carrying a black walnut. And, they heaped considerable
scorn upon a young Baltimore Oriole who was just investigating a
nearby day-lily. Especially notable was an all-out aggression
regarding a red squirrel who desired a pine cone from a nearby tree.
Both parents joined in here with an unrelenting number of attacks
which included several direct pecks to the squirrel’s head.
Being a parent is not work for the faint of heart!
--Dan (& Sandy) Thimgan
--
Thimgans
Battle Lake MN
Otter Tail County
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