Dear all
This is rather long - please ignore this unless you are
interested in the effects of electricity on birds.
My e-mails about the disappearance of our kestrels coinciding
with the erection of mobile phone antennae produced some helpful
and interesting replies.
For anyone with the time and wanting to sign up for a degree
with Charles Sturt Uni. - or anyone else, here goes:
The oldest (time between ringing and recovery) Kestrel recorded
so far in Australia was 7 years old, and that in Europe
(different species, equally lovely, rather darker) 16 years 2
months. 15-20 years lifespan would not be surprising.
So it's possible that our birds - known to have been there for
15 (NOT 25! - slap on wrist) years could have been one pair,
with our records over the last few years of a dead male, and of
a scarcely-mature male part of a nesting (? attempt?) pair might
be part of the normal problems of succession. In Britain nest
site fidelity seems to span generations.....
However mobile phone antennae could well pose risks. For people
these are the result of RFR (radio frequency radiation) which
can result in being burnt (as in a microwave oven). Our kestrels
gonads or - probably the most sensitive apparatus = their eyes
(which can see in the UV), could have been burnt.
Unfortunately my informants about the output of the antennae on
this church may have mixed up micro and milli watts so I can't
say for sure whether or not they exceed known damaging levels
for humans.
In any case frequencies of radiation which are not obviously
harmful for people may be harmful for other creatures (which is
why I referred in my first posting to magnetic resonance - and
human cancers are known to resonate more at....).
A different threat is from electro-magnetic radiation - as in
electricity distribution grids. In contrast to RFR, there is
some literature.
John Moulder who maintains the excellent US Cornell Uni website
on mobile phones and human health
http://iago.lib.mcw.edu/gcrc/cop/cell-phone-health-FAQ/toc.html#1
sent me these references:
Fernie, K. J. and Bird, D. M. Effects of electromagnetic fields
on body mass and food-intake of American kestrels. The Condor.
1999; 101:616-621.
Fernie, K. J.; Bird, D. M.; Dawson, R. D., and Laguë, P. C.
Effects of electromagnetic fields on the reproductive success of
American kestrels. Physiological and Biochemical Zoology. 2000;
73:60-65.
Fernie, K. J.; Leonard, N. J., and Bird, D. M. Behavior of
free-ranging and captive American Kestrels under electromagnetic
fields. Journal of Toxicology and Environmental Health. 2000;
59(Part A):101-107.
I'm looking forward to the thesis.
Michael Norris
Birding-Aus is on the Web at
www.shc.melb.catholic.edu.au/home/birding/index.html
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