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Fight over Flight
Since before the turn of the 20
On Nov. 3, 2006, the FCC issued a Notice of Proposed Rulemaking (NPRM), soliciting comments and data to help determine what impact the structures have on migratory fowl, whether tower lighting and guy wire regulations need to be modified, and if the FCC needs to adopt more stringent standards for environmental assessments of proposed tower sites when related to birds.
The FCC will accept comments until Jan. 20, 2007, and reply comments until Feb. 22, 2007.
In 1999, following the publication of several papers and the staging of various workshops on communications towers' effect on migratory birds, the Communication Tower Working Group (CTWG) was formed. Initial representation included the Federal Aviation Administration, the FCC, the National Association of Broadcasters (NAB), the Personal Communications Industry Association (PCIA), the U.S. Department of Agriculture's National Wildlife Research Center, the Cellular Telecommunications Industry Association, the National Audubon Society, the American Bird Conservancy and several universities.
Albert Manville, the senior wildlife biologist for the Department of Migratory Bird Management (United States Fish and Wildlife Service) was asked to chair the CTWG. Manville guesstimated that between four and five million birds are killed annually in tower collisions, extrapolating those numbers from research that had been done in 1999 by Bill Evans of the Ornithology Lab at Cornell University. In June 2000, the working group requested $15 million to properly research the issues and causes of avian mortalities related to towers.
Manville gripes that the broadcasters, the cell phone business and related industry firms haven't stepped forward to fund the studies. He points to the example of the power transmission and windmill industries that have also grappled with the bird kill situation, noting that they have "put millions in funding into the issue.
"If Verizon would take the cost of one of its prime time TV ads and donate that expense to a research effort dealing with the problems of birds and communications towers, it could fund a year's research," Manville said.
Broadcasters and other members of the communications industry see it differently. Dennis Wharton, senior VP of corporate communications at the NAB said, "The NAB has been an active participant in the USFWS' Communication Tower Working Group since its inception, and we stand ready to participate in future discussions and efforts. To ensure funding for research was procured through the proper channels, in June 2002 the NAB, PCIA and CTIA formally requested that Congress appropriate funds to research avian mortality at communications towers."
Patrick Howey, executive director of the National Association of Tower Erectors (NATE) said, "85 percent of NATE's tower service company members have 15 or fewer employees. Expecting a small trade association to fund studies the government itself is unwilling to finance does not seem fair or reasonable to me."
A source of debate
What seem to be the causes of the bird-tower collisions? The Avian Group, a coalition of nature lovers including the American Bird Conservancy (ABC), the Forest Conservation Council and Earthjustice, and Manville's Department of Migratory Bird Management point to several factors. First considerations are the same as real estate: location, location, location. Battles are being fought over the siting of towers on certain ridges in prominent migratory paths.
The ridge positions are often most desirable for proper RF coverage of target communities and areas, and the improvement of service and signal is the reason behind the new construction. Opponents of towers have two suggestions: don't use those ridges and reuse the existing towers already in place.
Gavin Shire, director of communication technology for the American Bird Conservancy, has a problem with the FCC's permission of "siting towers, particularly lit towers by wildlife refuges that are magnets for wildlife species…[as well as] siting them on ridge tops that are known to be major migratory pathways for birds. The FCC has given carte blanche to tower companies by not requiring them to complete environmental impact assessments. The emphasis needs to change there for individual towers to show that they are or are not going to affect migration."
Wharton of the NAB takes issue with that. "The FCC has been in compliance with all applicable environmental laws concerning tower siting. Because ‘major migratory pathways’ are undefined, it would be nearly impossible to site any communications tower, particularly east of the Mississippi."
"Adequate research of this issue has not been conducted, and yet discussions are being held about imposing restrictions," said Howey of NATE. "We are talking about efforts that will affect the nation's communications network for personal, business and national security purposes. The research needs to be completed first."
Height's not right
The Avian Group also finds fault with extremely tall towers, which are becoming more prevalent for DTV applications and for upgraded FM transmitter sites. Taller towers generally require more guy wires, and the installation of FAA-mandated obstruction lighting. It's the contention of the avian researchers that nocturnal migratory birds are most affected. In fog or haze, some of these night flyers are unable to rely on what have been termed "celestial cues." In the absence of stars and the moon, birds may be attracted to the steady glow of the tower sidelights. Studies indicate that the fowl begin circling the red lamps, sometimes fatally striking nearby guy wires, or colliding with the tower itself.
Groups have suggested several solutions. One option is to make use of existing towers to limit the increase of bird kills. Another option is to construct monopoles that don't need guys or build towers shorter than 200 feet in areas that are not within the known migratory bird passages. Unguyed towers of this size and placement would not require FAA lighting. Some research suggests that steady red sidelights and even white steady sidelights attract the sensitive eyes of birds, so perhaps further research will show that tower lighting should be strobes, since birds are not generally drawn to flashing or strobe lights.
"Very little is known about the effects lighting has on attracting avian species to communications towers," Wharton said. "We anticipate that the research that is being conducted in Michigan may yield some important findings that may guide the FAA and the FCC's decision-making process in tower lighting." Wharton refers to the data that Dr. Joelle Gehring of Central Michigan University has gathered under the auspices of the Michigan State Police, as it relates to their towers. Her statistics indicate that more than 95 percent of the bird fatalities involve collisions with guy wires, and that the steady-burning lights seem to attract more birds to tall structures.
In the past year, the Avian Group has filed a petition to the FCC to halt licensing and license renewals for all communications towers in the Gulf Coast region, as well as a suit against the FCC regarding seven towers in Hawaii that are alleged to be harming two endangered bird species. As it did in 2003, the group asked the FCC to halt the licensing process until it completes a full environmental assessment of the impact of towers on avian mortality.
Industry groups such as NATE, the NAB and the Wireless Association petitioned to intervene on the issue, refuting the Avian Group's claims that communications towers are substantially harming migratory bird populations, and added that the FCC has been diligently attempting to gather data on the issue of bird kills.
The American Bird Conservancy points to its own June 2000 report, Communications Towers: A Deadly Hazard to Birds, citing 230 species that have been registered as tower kills. Of that group, 52 species are on the Nongame Birds of Management Concern List, or on the Partners in Flight Watch List — species that are in decline and in need of USFWS management attention. The group seems most upset with the reported deaths of several members of an endangered species, the Red-cockaded Woodpecker.
The U.S. Fish and Wildlife Service admits that most of the available studies report only body counts of birds that have been found at tower sites, and that the research generally does not delve into presumed or suspected causes for these bird deaths.
Manville addresses the enforcement realities, too. "Our agents feel uncomfortable issuing tickets for bird kills at communications towers because they don't really have scientifically valid conservation measures that will definitively reduce kills other than what we know about height and guy wires."
Howey and communications industry representatives have also suffered frustration. "At the last meeting of the CTWG, an environmental group was allowed to offer its opinions on the situation, but industry representatives were not allowed to speak. Our concerns over how this process is unfolding continue to grow."
Slocum is a freelance writer based in Kansas City.
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