Changes in honeybee behaviour and biology under the influence of cellphone radiations
Posted by seumasach on May 29, 2010
Reports of such a colony collapse in nature in develop-
ing countries like India where electromagnetic radiation
(EMR) based technologies are comparatively new are
absent. It is possible that the electrosmog that prevails in
the advanced countries of the world has not yet affected
these countries. We are fortunate that the warning bells
have been sounded and it is for us to timely plan strate-
gies to save not only the bees but life from the ill effects
of such EMR.
CURRENT SCIENCE, VOL. 98, NO. 10, 25 MAY 2010 1376
*For correspondence. (e-mail: neelimark@yahoo.co.in)
Changes in honeybee behaviour and
biology under the influence of
cellphone radiations
Ved Parkash Sharma1 and Neelima R. Kumar2,*
1
Department of Environment and Vocational Studies, and
2
Department of Zoology, Panjab University, Chandigarh 160 014, India
Increase in the usage of electronic gadgets has led to
electropollution of the environment. Honeybee behav-
iour and biology has been affected by electrosmog
since these insects have magnetite in their bodies
which helps them in navigation. There are reports of
sudden disappearance of bee populations from honey-
bee colonies. The reason is still not clear. We have
compared the performance of honeybees in cellphone
radiation exposed and unexposed colonies. A signifi-
cant (p < 0.05) decline in colony strength and in the
egg laying rate of the queen was observed. The behav-
iour of exposed foragers was negatively influenced by
the exposure, there was neither honey nor pollen in
the colony at the end of the experiment.
Keywords: Colony strength, electromagnetic field,
foraging behaviour, honeybees.
RECENTLY a new phenomenon of sudden disappearance
of bees with little sign of disease or infection has been
reported from the world over. Bees simply leave the hives
and fail to return1,2. Colony collapse disorder (CCD) is
the name given to this problem. Bee colony collapse was
previously attributed to viruses, parasitic mites, pesti-
cides, genetically modified crop use and climate change.
On the basis of widely reported influences on honeybee
behaviour and physiology, electromagnetic field is
emerging as a potent culprit3.
The decimation of bees is seen as a grave risk to the
delicate equilibrium of the ecosystem. There is an urgent
need to understand the complicity of interaction involved
in the influence of electromagnetic radiations particularly
due to cellphones on honeybee biology and to work out a
strategy of development with minimal environmental
implications.
Four colonies of honeybees, Apis mellifera L, were
selected in the apiary of the Zoology Department, Panjab
University, Chandigarh. Two colonies T1 and T2 were
marked as test colonies. These were provided with
two functional cellphones of GSM 900 MHz frequency.
The average radiofrequency (RF) power density was
8.549 μW/cm2 (56.8 V/m, electric field). The cellphones
were placed on the two side walls of the bee hive in call
mode. Electromotive field (EMF) power density was meas-
ured with the help of RF power density meter (Figure 1).
Blank colony (B) was equipped with dummy cellphones,
while the control colony (C) had no cellphones.
The exposure given was 15 min, twice a day during the
period of peak bee activity (1100 and 1500 h). The ex-
periment was performed twice a week extending over
February to April and covering two brood cycles.
The following biological aspects were recorded during
observations.
Brood area: The total area under brood comprising
eggs, larvae and sealed brood was measured in all the
experimental colonies with the help of a 1 sq. cm grid
mounted on a comb frame4.
Queen prolificacy: This was measured in terms of egg
laying rate of the queen. In order to determine the number
of eggs laid by the queen per day, the total brood area
measured was multiplied by a factor of 4 to calculate the
total number of cells containing the brood (there are 4
cells per sq. cm of comb). This number was divided by 21
(as the average time taken for an egg to change into an
adult worker is 21 days) to get the egg laying rate of the
queen5.
The queen prolificacy was calculated as:
2
Totalbroodarea(cm) 4
QP .
21
×
=
The following behavioural aspects were observed.
Foraging: (i) Flight activity measured as number of
worker bees leaving the hive entrance per minute: before
exposure and during exposure. (ii) Pollen foraging effi-
ciency measured as number of worker bees returning with
pollen loads per minute: before exposure and during ex-
posure. (iii) Returning ability determined by counting the
Figure 1. Experimental colony showing placement of mobile phones
and power density meter.
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CURRENT SCIENCE, VOL. 98, NO. 10, 25 MAY 2010 1377
Table 1. Changes in foraging behaviour of Apis mellifera exposed to cellphone radiations
Parameter Control (mean ± SD) Treated (15 min exposure) (mean ± SD)
Flight activity
(No. of workers bees leaving the hive entrance/min)
Before exposure 35.9 ± 13 (12–61) 34.1 ± 10 (18–48)
During exposure 37.2 ± 12 (12–72) 22.8 ± 6 (13–34)
Returning ability
(No. of worker bees returning to the hive/min)
Before exposure 39.6 ± 13 (12–61) 36.4 ± 11 (21–58)
During exposure 41.3 ± 11 (14–78) 28.3 ± 8 (16–48)
Pollen foraging efficiency
(No. of worker bees returning with pollen loads/min)
Before exposure 7.0 ± 2 (4–9) 6.3 ± 2 (4–10)
During exposure 7.2 ± 2 (4–11) 4.6 ± 2 (2–7)
Table 2. Changes in colony status of Apis mellifera exposed to cellphone radiations
Parameter Control (mean ± SD) Treated (15 min exposure) (mean ± SD)
Bee strength
Start 7 frame 7 frame
End 9 frame 5 frame
Brood (cm2)
Total brood
Start 2033.76 ± 182.6 (7–532) 2866.43 ± 169.0 (0–574)
End 1975.44 ± 138.8 (0–427) 760.19 ± 111.0 (0–348)
Prolificacy (egg laying rate/day)
Start 387.24 545.9
End 376.20 144.8
Honey stores (cm2) 3200 400
Pollen stores (cm2)
Start 230.5 ± 21.60 (198–305) 218.2 ± 17.48 (141–241)
End 246.7 ± 16.94 (195–289) 154.7 ± 7.30 (142–168)
number of worker bees returning to the hive per minute:
before exposure and during exposure.
Colony growth: (i) Bee strength: measured as total
number of bee frames per colony. (ii) Honey stores: the
area containing ripe and unripe (sealed and unsealed)
nectar was measured in sq. cm with the help of the grid4.
(iii) Pollen stores: the portion of comb containing cells
filled with stored pollen was measured by the grid
method. It was expressed in sq. cm.
The results of the studies carried out on biological and
behavioural aspects of the colonies exposed to cellphone
radiations for a duration of 15 min are presented in
Tables 1 and 2.
It was observed that the total bee strength was signifi-
cantly higher in the control colony being nine comb
frames as compared to only five in the treated colony at
the end of the experiment. There were no dead bees in the
vicinity of the hive which is a characteristic of this disorder
reported by other workers9,10. The area under brood
declined to 760.19 cm2 which was significantly less than
the control (1975.44 cm2).
The queen exposed to cellphone radiations produced
fewer eggs/day (144.8) compared to the control (376.2).
It has previously been reported that there is queen loss in
colonies exposed to high voltage transmission lines11 or
exposure of the queen bee to cellphone radiations stimu-
lated her to produce only drones12.
The number of returning bees declined. Another impor-
tant finding was that the number of bees leaving the hive
also decreased following exposure (Table 1). There was
no immediate exodus of bees as a result of this interfer-
ence, instead the bees became quiet and still or confused
as if unable to decide what to do. Such a response has
however not been reported previously.
As the total number of returning bees decreased
(28.3 bees/min) so did the number of pollen foragers re-
turning to the hive (4.6). This led to decrease in the area
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CURRENT SCIENCE, VOL. 98, NO. 10, 25 MAY 2010 1378
*For correspondence. (e-mail: varghesefsi@hotmail.com)
under pollen stores from 246.7 cm2 in control to
154.7 cm2 in the treated colonies.
The honey storing ability declined due to loss of re-
turning bees and at the end of the experiment there was
neither honey, nor pollen or brood and bees in the colony
resulting in complete loss of the colony. Similar condi-
tions have been observed by other workers in case of
honeybees under the influence of high tension lines13–15.
Bee hives located near high voltage power lines in fields
as low as 4 Kv/m produced less honey and had high mor-
tality rates. It was also observed that colonies exposed to
strong electric fields produce less honey16. The present
study therefore suggests that colony collapse does occur
as a result of exposure to cellphone radiations.
Reports of such a colony collapse in nature in develop-
ing countries like India where electromagnetic radiation
(EMR) based technologies are comparatively new are
absent. It is possible that the electrosmog that prevails in
the advanced countries of the world has not yet affected
these countries. We are fortunate that the warning bells
have been sounded and it is for us to timely plan strate-
gies to save not only the bees but life from the ill effects
of such EMR.
1. Hamzelou, J., Where have all the bees gone? Lancet, 2007, 370,
639.
2. Sylvers, E., Case of disappearing bees creates a buzz. The New
York Times, 22 April 2007; http://www.nytimes.com/2007/04/
22/technology/22iht-ireless23.1.5388309.html (accessed on 13
June 2009).
3. Carlo, G. L., Radiation is killing the bees despite the cellphone
industry’s disinformation campaign, 2007; http://www.
buergerwelle.de/pdf/radiation_is_killing_the_bees.htm (accessed on
3 August 2009).
4. Al-Tikrity, W. S., Hillman, R. C., Benton, A. W. and Clarke Jr,
W. W., A new instrument for brood measurement in honeybee
colony. Am. Bee J., 1971, 111, 20–21.
5. Sharma, P. L., Brood rearing activity of Apis indica F. and egg
laying capacity of its queen. Indian Bee J., 1958, 20, 166–173.
6. Stever, H. and Kuhn, J., Schutz der Bienen vor Handy–Strahlung
(Protection of bees from mobile phone radiation). Schweizerische
Bienen-Zeitung, 2001, 124(9), 23–27.
7. Kuhn, J. and Stever, H., Einwirkung hochfrequenter elektro-
magentischer Felder auf Bienenvolker (Effects of high frequency
electromagnetic fields on bee populations). Deutsches Bienen-
journal, 2002, 10(4), 19–22.
8. Harst, W., Kuhn, J. and Stever, H., Can electromagnetic exposure
cause a change in behaviour? Studying possible non-thermal in-
fluences on honeybees – an approach within the framework of
educational informatics. Acta Syst. Int. J., 2006, 6(1), 1–6.
9. Richter, K., Varrora mite or electromagnetic fields? New research
into the death of bees. Kompetenzinitiative, 2008; http://www.
kompetenzinitiative.de/international/press-releases/varroa-mite-or-
electromagnetic-fields.html (accessed on 2 June 2009).
10. Bowling, M., Where are the birds and bees? The prescription for
safe wireless, EMRX, 2008; http://www.emrx.org/where-birds-and-
bees.html (accessed on 2 June 2009).
11. Greenberg, B., Bindokas, V. P. and Gauger, J. R., Biological ef-
fects of a 765 kV transmission line: exposure and thresholds in
honeybee colony. Bioelectromagnetics, 1981, 2(4), 315–328.
12. Brandes, C. and Frish, B., Production of mutant drones by treat-
ment of honeybee with X-rays. Apidologie, 1986, 17(4), 356–358.
13. Wellenstein, G., The influence of high tension lines on honeybee
colonies. Z. Ange. Entomol., 1973, 74, 86–94.
14. Warnke, U., Bienen unter Hochspannung (Bees under high
voltage) (original article in German). Umschau, 1975, 13, 416.
15. Warnke, U., Effect of electrical charges on honeybees. Bee World,
1976, 57(2), 50–56.
16. Carstensen, E. L., Biological Effects of Transmission Line Fields,
Elsevier, New York, 1987, p. 397.
ACKNOWLEDGEMENT. Research facilities provided by Prof. R. K.
Kohli, Department of Environment and Vocational Studies, Panjab
University, Chandigarh are greatly acknowledged.
Received 12 August 2009; revised accepted 20 April 2010
Impact of tuna longline fishery on the
sea turtles of Indian seas
Sijo P. Varghese*, S. Varghese and
V. S. Somvanshi
Fishery Survey of India, Botawala Chambers, Sir P.M. Road,
Mumbai 400 001, India
Longline fishery is exerting an impact on the sea turtle
populations of the seas around India, as in the case of
many longline fisheries operating in other parts of the
world. During the tuna longline survey conducted by
four research vessels of Fishery Survey of India, 87
sea turtles were caught incidentally from the Arabian
Sea, Bay of Bengal and Andaman and Nicobar waters
of the Indian exclusive economic zone (EEZ) during
2005–08, registering an overall hooking rate of 0.108
turtles per 1000 hooks operated. There were marked
differences in the hooking rates of turtles recorded
from these three regions of the Indian EEZ, the
maximum hooking rate being recorded from the Bay
of Bengal (0.302), followed by the Arabian Sea (0.068)
and Andaman and Nicobar waters (0.008). The species
of sea turtles recorded in the bycatch, in order of
abundance, were olive ridley (Lepidochelys olivacea),
green (Chelonia mydas) and hawksbill (Eretmochelys
imbricata) turtles. This study provides quantitative
data on the magnitude of sea turtle incidental catch of
the tuna longline fishery in the Indian EEZ.
Keywords: Arabian Sea, Andaman and Nicobar waters,
Bay of Bengal, hooking rate, longline.
SEA turtles are among the most extraordinary, charismatic
and fascinating creatures, and are some of the world’s
greatest nomads, sometimes navigating thousands of
miles between feeding and nesting grounds. Six of the
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