Date: 5/7/25 1:52 pm From: njmann90 via groups.io <njmann50...> Subject: [slocobirding] thanks for lunch and woodpeckers
From Birds of the World
Power Struggles
The most dramatic agonistic interactions occur during power struggles,
intense fights occurring in association with the filling of reproductive
vacancies within groups (97
<https://birdsoftheworld-org.cuesta.idm.oclc.org/bow/species/acowoo/cur/references#REF1880>,
102
<https://birdsoftheworld-org.cuesta.idm.oclc.org/bow/species/acowoo/cur/references#REF38392>).
Reproductive vacancies occur when all the breeders of 1 sex die or
disappear and are generally filled by unrelated birds from outside the
group to the exclusion of a related helper of the missing sex still present
in the group. The right to fill such vacancies may be contested by up to 20
or more nonbreeding helpers from other social groups who fight, often in
unisexual sibling units, in contests lasting days or weeks and involve
nonstop fighting, chasing, and vocalizations associated with intruders such
as *Urrks*, *Garricks*, and drumming. Power struggles occur over vacancies
of either sex but are generally more intense over female vacancies. The
length of and number of intruders involved in power struggles are
positively correlated with territory quality as measured by size of storage
facilities. Power struggles are generally won by the largest participating
coalition of siblings. Winners remain and share breeding status in the new
territory, whereas losers return home to their natal groups and resume
their status as nonbreeding helpers.
During power struggles and other kinds of territorial skirmishes, birds
vocalize and chase extensively, occasionally making contact and grappling
with adversaries. While grappling, birds peck at each other's heads and
drop, sometimes hitting the ground and remaining for several seconds before
disengaging and flying away.
Pretty much describes what we saw at Las Pilitas
N
--
Nancy Jean Mann
San Luis Obispo
“I wish it need not have happened in my time," said Frodo.
"So do I," said Gandalf, "and so do all who live to see such times. But
that is not for them to decide. All we have to decide is what to do with
the time that is given us.”
― J.R.R. Tolkien, The Fellowship of the Ring…
See more
