This is what happens when biologists start playing with electronics.
To make this is more valid experiment, I would mount the telephones remotely, and use external antenna in the hive, fed via coax from the remote telephones.
Their control of a telephone in standby was not a good control. The standby telephone has it's power supply in a low current state to save battery power. This results in a couple of things.
There is significantly less heat generated by a standby telephone than an active telephone. Bees respond to temperature.
Modern electronics use switching power supplies. These switch currents through inductors at high frequency to step the battery voltage to the IC's operating voltage at high efficiency. You can often hear these switching supplies, as they cause the inductors to "sing", as the high frequency is demodulated down into the audible band by component imperfections. So, the bees may be responding to acoustic noise from the power supply.
We have no idea what else is going on in these phones. is there a backlight on the LCD? If it's electroluminscent, that also can sometimes be heard, as it has it's own, much higher voltage supply. If it's LED, that will be generating heat.
If the experiment is repeated, please use remote telephones with external antenna in the hive.
The study's conclusion is far less dramatic then the sensationalized headline implies, but does include the following lines:
"Further confirmation of the current results and their implications regarding a direct correlation between erratic honeybee behavior and mobile phone-generated electromagnetic fields would substantiate one more explanation for the “disappearance” of bee colonies around the world. This phenomenon accounts for 43% of all bee losses, apart from overwintering (39%), mite disease, (15%) and pesticides (3%) as recently described in a national survey performed in the United States (Bee Alert Technology 2007). Experiments should be undertaken to establish the correlation between the time necessary for the onset of worker piping and the intensity of the electromagnetic fields present in the vicinity of the beehive. For future experiments, in complement to the present original study and in order to reach more “natural” conditions, mobile phone apparatuses should be placed at various increasing distances away from the hives. Video recordings showing the modifications in the bees’ behavior in the hive should also be performed."
I'll assume they didn't choose phones with additional antennae activated (ie, bluetooth, GPS, wifi), but that wasn't detailed either.
Also since they focused on 900Mhz GSM, I wonder if CDMA/TDMA or non-900Mhz GSM would change results... assuming equivalent specific energy adsorption rate (SAR), of course.
The original link is the full text of the study, in HTML format, not a citation thereof. If PDF is your preference it's already been linked in the comments here.
To make this is more valid experiment, I would mount the telephones remotely, and use external antenna in the hive, fed via coax from the remote telephones.
Their control of a telephone in standby was not a good control. The standby telephone has it's power supply in a low current state to save battery power. This results in a couple of things.
There is significantly less heat generated by a standby telephone than an active telephone. Bees respond to temperature.
Modern electronics use switching power supplies. These switch currents through inductors at high frequency to step the battery voltage to the IC's operating voltage at high efficiency. You can often hear these switching supplies, as they cause the inductors to "sing", as the high frequency is demodulated down into the audible band by component imperfections. So, the bees may be responding to acoustic noise from the power supply.
We have no idea what else is going on in these phones. is there a backlight on the LCD? If it's electroluminscent, that also can sometimes be heard, as it has it's own, much higher voltage supply. If it's LED, that will be generating heat.
If the experiment is repeated, please use remote telephones with external antenna in the hive.