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[SANET-MG] mobile phones and birds
poultry producers might take a careful look at the possible effects of
base stations on thie flocks?
http://www.i-sis.org.uk/MPVB.php
Scientists for a GM Free Europe - ISIS/Green Network/TWN International
Briefing at the European Parliament, Brussels 12th June 2007.
ISIS Press Release 29/05/07
Mobile Phones & Vanishing Birds
Birds near mobile phone base stations do not breed well Dr. Mae-Wan Ho
A fully referenced version of this article is posted on ISIS members’
website.
An electronic version of this report, or any other ISIS report, with
full references, can be sent to you via e-mail for a donation of £3.50.
Please e-mail the title of the report to: report@i-sis.org.uk
Where did all the sparrows go?
The sparrows have disappeared completely from the cities at least four
years ago in Britain, as mobile phones grew in popularity. Third
generation (3G) mobile phones were introduced in 2003, and there were
over 65 million users in the UK by the end of 2005, more phones than
people [1]. Did mobile phone transmitters cause the sparrows to
disappear [2]?
Scientists at the Research Institute for Nature and Forests in Brussels,
Belgium, have produced the first evidence that mobile phone base
stations are affecting the reproductive behaviour of wild sparrows [3].
This finding comes as mobile phones are held suspect in the massive
collapse of bee colonies all over the United States and Europe [4] (
Mobile Phones and Vanishing Bees , SiS 34).
Joris Everaert and Dirk Bauwens wanted to know if the low intensity
microwave radiation from mobile phone base stations has any effect on
the number of house sparrows during the breeding season. They identified
150 locations distributed over six residential districts in Gent, Sint
and Niklaas in the province of East Flanders, where they counted the
number of male house sparrows and measured the strength of
electromagnetic radiation from base stations.
The study areas were similar, with abundant hedges, bushes, and other
vegetation between the houses, and one or more GSM (Global System for
Mobile Communications) base stations nearby. All locations were along
small roads within the residential areas and at variable distances from
the nearest GSM (mean 352 m, range 91-903 m, about 90 percent at 100-600
m). On days when the weather was favourable, so male sparrows would be
out singing, the researchers went to each location between 7 and 11 am,
and using binoculars, counted the number of male sparrows within a
radius of about 30 m for a period of five minutes.
Simultaneously, they measured the maximum value of the electric field
strength (in V/m) from the GSM 900 MHz and GSM 1800 MHz base station
antennas during 2 minutes for each frequency band, using a portable
calibrated high-frequency spectrum analyser.
Everaert and Bauwens found that the number of house sparrow males varied
between zero and four at the different locations. The measured electric
field strengths were seldom higher than 1V/m, and most often well below
that value. Nevertheless, the spatial variation in the number of house
sparrow males was negatively and highly significantly correlated to the
strength of electric fields from both the 900 and 1800 MHz frequency
bands and from the sum of these bands. This negative correlation was
very similar within each of the six districts, despite differences in
both the number of birds and radiation levels.
Fewer house sparrow males were seen at locations within relatively high
electric field strengths of GSM base stations. For example, the mean
number of male sparrows varied from 1.9 at the combined field intensity
of 0.13 V/m to 0.8 at a combined field intensity of 0.247 V/m.
The results, though preliminary, do support the hypothesis that
long-term exposure to higher levels of radiation negatively affects the
abundance or behaviour of house sparrows in the wild. Fewer males
singing would mean less breeding success.
White storks breeding success plummets near mobile phone transmitters
Sparrows are not the only wild birds affected. Phone masts were found to
actually reduce the breeding success of white storks in Spain.
Alfonso Balmori, a conservation biologist in Valladolid, Spain, reported
a significantly lower number of white stork ( Ciconia ciconia )
fledglings in nests close to mobile phone transmitters compared to nests
further away [5].
To monitor the breeding success of the white stork population, 60 nests
were selected and visited from May to June of 2003. The selected nests
had similar characteristics. They were located on the roof of churches
and buildings inside urban centres in Valladolid. As the cell phone
transmitters are everywhere, very few places had zero background
intensity. So nests were chosen that were exposed at very high or very
low levels of EMR, depending on the distance from the nests to the
antennas.
Thirty nests were located within 200 m of one or several antennae
(GSM-900 MHz and DCS-1800 MHz) placed on masts and on the roof of the
buildings at a height of 15-30 m. Another 30 chosen were located further
than 300 m from any transmitter. The nests were observed with telescopes
and the number of young counted. The electric field intensity in V/m was
measured.
The average number of fledgling produced per nest in nests located
within 200 m of phone antennae was 0.86 + 0.16. For nests located
further than 300 m, the number was 1.6 + 0.14. Twelve nests (40 percent)
close to the antennae were without young, as opposed to one nest (3.3
percent) among those further than 300 m.
The mean electric field of nests within 200 m was 2.36 + 0.82V/m
compared to 0.53 + 0.82V/m for nests further than 300 m.
Balmori also found difference in how the birds behaved close to the
phone antennae. Young birds died from unknown causes, and bird couples
frequently fought while constructing their nests. Sticks fell to the
ground, and the couple failed to make any headway. Some nests were never
completed and the storks remained passively in front of the antennae.
Laboratory studies show bird embryos die when exposed to microwaves
The observations in urban sparrows and the white stork population
suggest that microwave radiation interferes with reproductive behaviour
and breeding success, which would have decimated the wild populations.
But that's not the whole story.
Several million birds of 230 species die each year from collisions with
telecommunications masts in the United States during migration [6].
Accidents happen mainly in the night, in fog, or bad weather, when birds
might be using the earth's magnetic field for navigation, and could be
seriously disoriented by the microwave radiation from telecommunication
masts.
In the UK, where the allowed radiation level is 20 times higher than in
Spain, a decline of several species of urban birds has occurred [2],
coinciding with the increasing installation of mobile phone masts.
Birds are good candidates as biological indicators for low-intensity
electromagnetic radiation (EMR); they have thin skulls, their feathers
can act as dielectric receptors of microwave radiation, many species use
magnetic navigation, they are very mobile and possible psychosomatic
effects are absent, as Everaert and Bauwens [3] point out.
Another important factor is that chicken embryos subjected to the
radiation from a cell phone in the laboratory suffered much higher
mortalities than non-exposed controls. Some years ago researchers in
Russia showed that continuous exposure of the chick embryos during the
21 days of embryonic development resulted in 75 percent of the embryos
dying, compared with 16 percent in the controls [7].
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