Radio and utility towers can cause injury or death for avian populations that crash into them, so vendors such as P & R Technologies of Portland, Ore., are developing new lighting beacons to mitigate such events.

According to the U.S. Fish and Wildlife Service, between 5 million and 50 million birds are killed in the U.S. each year after being attracted by the lights on communication towers and then colliding with the tower's structure or guy wires. Last year the FCC suggested towers in excess of 200 feet should project medium-intensity white strobe beacons to make them more conspicuous at night — as opposed to the current red obstruction lighting systems — to reduce avian deaths.

P & R Technologies recently released a medium-intensity strobe light, model L86, to address the issue. It requires 120 V or 230 V AC power, weighs 21 pounds, and meets the Federal Aviation Administration's requirement to mark obstructions in order to mitigate avian deaths, said George Osgood, the company's president.

During the daytime, this dual-density white beacon emits 20,000 candelas and uses 95 watts of power. (A candela is the base unit of luminous intensity, or the power emitted by a light source in a particular direction.) At night, the emitted light is reduced to 2000 candelas, with a corresponding reduction in power consumption to 35 watts, according to Osgood.

“Now, birds are very smart and have fooled humans for years, so we try to guess as to what affects them and what attracts them,” Osgood said. “So in essence, there is a thought out there that birds may be attacted to a flashing or steady red light. So the white strobes are hoped to deter them from running into lines or making a home on top of towers.”

However, not every entity is convinced. For instance, the National Public Safety Telecommunications Council submitted comments to the FCC on April 26, 2007, regarding the effects of communications towers on migratory birds. NPSTC stated that “the widely divergent positions mask an underlying need to ascertain the financial and logistic effects of mounting white strobe lights, prohibiting guy wire infrastructure and reducing tower heights. All have the potential to impose significant resource demands on licensees.”

In response, Osgood said his company — as well as other industry vendors — would continue to work with biologists to learn more about the issue. In the meantime, tower operators also will continue to grapple with it as they try to balance the needs of their customers, the avian populations — and their own bottom lines.

Tower & site vendors

Aluma Tower Co. ▪ Andrew Corp. ▪ Astron Wireless Technologies ▪ Bartley Machines ▪ Bearcom ▪ Carlson Wireless Technologies ▪ Com/Rad ▪ CommScope ▪ Comprod Communications ▪ DLC ▪ DX Radio Systems ▪ EMR ▪ Fiber-Span ▪ Fiplex ▪ Hark Systems ▪ Harris/RF Communications ▪ Havis Shields Equipment ▪ Hutton Communications ▪ JFW Industries ▪ Polyphaser ▪ Radio Frequency Systems ▪ Radio Waves ▪ RF Industries ▪ Sabre Site Solutions ▪ Sinclair Technologies ▪ Talley Communications ▪ Telewave ▪ Tessco ▪ Times Microwave Systems ▪ Zetron ▪ For complete listings of location and tracking-system vendors, visit the MRT 2008 Resource Guide at www.mrtmag.com.

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