Hi All,
I'm posting this because a Miami U. alumnus was involved in this research
(see below) while he was pursuing a Ph.D. at Cornell. This Miami U. Alum
(Jay Mager) was a grad student in Zoology and was one of the original
participants of the Skyline Chili Challenge oh so many years ago, and was
pretty heavily involved with Audubon Miami Valley (when it was Oxford
Audubon). Jay has a stellar birding ear and for years was the guy who
trakced down Wild Turkeys & Eastern Screech-owls for the area Christmas
Bird Count (usually up near the Cedar Falls trail at Hueston Woods).
Jay is now back in Ohio and is a professor at Ohio Northern University,
where he teaches ornithology. I had the good fortune of running into him
the other night while visiting with an Audubon Chapter in Lima, Ohio and
found out he and his wife (who is a professor at Denison U.) are trying to
find a house in Marysville, OH. If you ever make it up to Ada (Ohio
Northern U.) or up around the greater Columbus area definitely look Jay up
and say "hi!" We're fortunate to have him back in Ohio and contributing to
our knowledge of Ohio's birds.
Casey
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http://www.news.cornell.edu/stories/March06/LoonyTunes.kr.html
March 7, 2006
Moving loons change their tunes
By Krishna Ramanujan
Bird experts believed for years that once a bird learned songs, the calls
stayed relatively fixed for life. But a new Cornell University study finds
that male loons change their tunes when they move into a new territory.
The study, to be published in the March issue of the international
publication Animal Behaviour, reports that while female loons usually
disperse over a wide area when ready to breed, males tend to stake claim to
a small lake or section of a larger lake near where they were hatched. But
rivals often challenge resident males and fight for the territory and the
females. The fights can be to the death, with males diving and rising up
under a foe in an effort to spear a rival through the chest and heart with
his long, pointed beak.
It turns out that the victor gets more than the female -- he gets a new
voice: He changes his vocalization, called a yodel, to a new call that is
very different from the loser's yodel.
"It's as if they are trying to say, 'I'm the new boy on the block,'" said
the paper's lead author, Charles Walcott, professor of neurobiology and
behavior at Cornell. "Why that should be important, we really don't know."
The researchers recorded 527 yodels of 16 male loons on 21 lakes at the
Seney National Wildlife Refuge in Seney, Mich., and 3,107 yodels of 82
loons on 63 lakes near Rhinelander, Wis. All the birds were banded as part
of well-studied populations.
Yodels of male loons are unique from their neighbors on other lakes and
stay stable from year to year. But, of 13 male loons whose yodels were
recorded before and after they changed territories, 12 substantially
changed their yodels within two years, and the new resident's yodel changed
in ways that increased its difference from that of the previous resident.
"This result implies that loons not only change their vocalizations as the
birds change territory, but also that the new owner is familiar with the
yodel of the resident that it replaces," said Walcott. And, nobody yet
knows whether other species of birds also change their tunes when they move
into a new territory.
Some biologists have advocated using sound as a way to identify specific
birds, as opposed to netting and tagging birds, which may be
traumatic. "But since the loons change their vocalizations, it means you
can't do that," said Walcott.
The research provides valuable insights into the loon's social and
territorial behavior, which has implications for conservation efforts,
Walcott noted. With legs near the back of the body, these streamlined, fish-
eating water birds are awkward and vulnerable on land, so they prefer to
nest in swampy areas with easy access to deep water. But, as more people
build houses along lake shores, the loon's swampy nesting habitats near the
shores are increasingly replaced with lawns. As a result, people build
nesting platforms for loons on the water. But the loons fight over the
platforms, which has led in some areas to too much fighting and not enough
breeding. Researchers now recognize the need to coordinate where and how
many such platforms are put on a lake.
"By understanding the loons' social system, we can help people and loons
live together," said Walcott.
The study was funded by the Whitehall Foundation, the New Hampshire
Charitable Foundation, the National Science Foundation and Cornell. Co-
author Walter Piper, a biologist at Chapman University, contributed the
behavioral analysis while Walcott and graduate student Jay Mager focused on
collecting and analyzing the acoustic data.
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