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Having been on more sites with towers, guyed masts, curtain antennas, and beams than I can ever even think about counting, you would have thought that I would have seen quite a few dead birds lying underneath those structures.

I don’t ever remember seeing one, not one…

Those antennas ranged from 20 feet high (a TV transmitter using ducting across the Gulf from Saudi into Iran with 24/7 Quoran as content) up to 1265 feet (the second structure to be built at the inhospitable Emley Moor, Yorkshire).

The Emley Moor tower was, at the time, the tallest self-supporting structure in Europe. It was a steel tube which attracted a lot of ice and on March 19, 1969 it buckled and collapsed. I’ve made a lot of log entries in my career – I automatically look at a clock at the occurrence of an event – but I’ve never had the grim opportunity to write the log entry that the control room engineer made that day:


It later transpired that it wasn’t the ice that brought the tower down, but resonance of slow oscillation from the seemingly ceaseless wind across the moor. Two similarly designed towers, neither as tall, were modified by damping – with huge chains dropped down the center of the structure.

So, when we are told that perhaps 50 million birds are being downed by communications towers every year, what the heck is happening? We cannot disbelieve the narrators, I presume, because they must have displayed the corpses to someone at some time. But why would this be happening?

Is it the lower heights of basestation antennas? Lack of color bands used in taller structures? Inadequate lighting, or type of lighting?

I can accept that I have never worked at a transmitting station that was on a major bird migration path. And maybe that is one element of the situation: a sort of “local birds know the territory,” but the ones passing through twice a year didn’t Google their path very efficiently before takeoff.

Now we have another one of those wonderful environmental Catch-22s: bats being found dead at the base of wind turbines. Which is the worst “green” crime? Killing bats or not using renewable energy?

It reminds me of a time when I lived in Oregon, after escaping from California, and was still working at Electronic Design (a long distant time ago when all the Editors were engineers specialized in their fields). Across the hallway from my office (which backed on to the police station and volunteer fire department – boy, did my Editor-in-Chief at that time, Tom Halligan, go nuts when the sirens went off during an Editorial conference call!) was a group of researchers from The University of Oregon who were trying to prove the great dangers that Spotted Owls were facing because of logging. Some owls had been tagged with RF collars and the graduates went out regularly to trace where they were carrying their little VHF Yagis and receivers. The research was abandoned after they found that the owls traveled less than 100 feet from their home tree. Was that research published? Oh, no!

So, back to the bats. I’m not sure that I like rodents of any kind, and I’ve never had any personal feelings towards bats, but they are creatures and their lives should not be in our hands. The CIA may have thought they were dispensable loaded with miniature bombs, but they thought the same thing about cats and I’ll defend moggies to the last.

Postgraduate students at the University of Calgary (why aren’t they researching stampedes or something?) have studied bat deaths at wind farm installations. They have concluded from necropsies that the bats were not killed by strikes from the blades, but by some reducing air pressure effect in their lungs that made the lungs burst as they flew past the tips of the rotating blades. Their radiolocation enables them to avoid the bulk rotating mass of the blades, but the tip effects cannot be so detected.

The air pressure change is a natural effect of a decent blade design – just like an airplane prop – with some lift effects associated with it. But, like an airplane prop, it is unnecessary for operations. A plane climbs because of power: power equals lift, you are taught in ground school (or should be).

Changing wind turbine blade design to provide the lift necessary for the wind to be effective is easy. Educating bats to avoid the blade tips sounds much more difficult and I don’t intend to count bats instead of sheep during my attempts to sleep. Lanolin sounds like a much better sell to America than guano.