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Female
chickadees
love the lead
singer
WASHINGTON
(AP) — The love life of a
female chickadee
could make a country music classic: "If your song don't pass muster,
buster,
I'm gone."
The
lady
chickadee has a cheatin' heart,
quick
to find another lover if her mate fails to win his daily song contests
with rivals. In effect, she decides that if her mate is a loser, he
won't
be the only papa in her nest, say researchers at Queen's University in
Kingston, Ontario.
Daniel
Mennill, co-author of a study
appearing
Friday in the journal Science, said mates of high-ranking male
black-capped
chickadees are more likely to be unfaithful than are the mates of
lower-ranked
males.
"Females
are accustomed to hearing their
high-ranking
mates dominate a song contest," Mennill said. "It is quite a shocking
event
to their ears to hear them lose a song contest."
When
that
happens, he said, the female
will sneak
out before dawn and meet with a rival male for a coupling. Then she
flies
back home as if nothing happened and continues to live with her
partner.
"These
extra matings are just short
copulations
— about 30 seconds," said Mennill. The long-term partners "do remain
mated,
in a social sense."
The
effect of
these extra matings is that
some chicks
in the nest have been fathered by some other male chickadee, he said.
And
the betrayed male apparently never knows.
Mennill
said
he established by DNA
analysis of blood
from the chicks that one or two birds per clutch had a father than the
one that raised them.
Male
chickadees are challenged virtually
every day
to a song contest with rival males. They use the contests to defend
territory
and nests.
"It is
only
the males that sing," said
Mennill.
"Every male chickadee has only one song — two notes that sound like
'fee-bee."'
One
male
sings and the other then sings
back in
a competition that may last for several minutes.
"If a
male is
very aggressive, he'll go
through
a set of routines where he will match the pitch and try to overlap the
song of his opponent," Mennill said.
While
this is
going on, the female is
listening,
gauging who is winning. If her mate loses, she remembers.
Mennill
proved the chickadee cheating by
recording
some of the bird songs and then engaging in a singing contest with a
male
bird.
"The
main
effect is that the female is
more likely
to engage in extrapair copulations if the high-ranking partner was
bested."
"A few
times
I have seen a male follow the
female
and it did turn into a bit of a fight between the two males and the two
females," said Mennill. "But usually these things are very quick and
the
female can sneak away and be back before her mate notices."
The
females
of high-ranking males are most
likely
to cheat, he said. Rank among chickadees is established in the fall
when
the birds gather in flocks that will last through the winter. Somehow
the
birds establish an Alpha, or primary, male and female, a Beta, or
second
in rank, male and female, and so on.
"There
is an
Alpha chickadee for whom the
others
make way at a food source," Mennill said. "The lowest ranking bird has
to wait for everyone else."
Even
though
chickadee partners may stay
together
for years, the birds do have a system rather like divorce, said
Mennill.
If, for
instance, the Alpha female dies or
is grabbed
by a hawk, then the Alpha male becomes a nestwrecker.
"Within
24
hours, the Beta female will
divorce her
partner and pair with the Alpha male, leaving the Beta male alone,"
Mennill
said. "The females will do a lot of social changing in order to pair
with
a higher ranking male."
Sounds
like
another country song.
Copyright 2002
The Associated
Press.
All rights
reserved.
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05/02/2002
- Posted 03:27 PM ET 
