WASHINGTON — The debate over whether towers kill migratory birds has been a contentious issue at the commission for at least eight years and has taken another twist.
The FCC has drafted rules and procedures designed to ensure that environmental effects of proposed towers — including their impact on migratory birds — are considered before a tower is built or substantially changed; and it has been taking comments on those proposed rules.
After conservation groups opposed the FCC’s tower siting approval process three years ago, a federal appeals court said the commission had to offer the public “a meaningful opportunity” to ask for an environmental assessment study for proposed towers.
The new draft procedures parallel an understanding reached in 2010 by communication providers, including NAB, the Wireless Association, tower companies and conservation groups.
Source: FCC Antenna Structure Registration (ASR)
Under the draft, the public would be able to comment on environmental effects of a proposed tower. The FCC staff would consider those comments and determine whether an environmental assessment is required.
If needed, the EA would have to be completed before tower registration; those now are filed concurrently.
The commission initially would require an EA for requests to register towers of more than 450 feet. However, the FCC said it may modify this requirement after further study. Towers between 351 and 450 feet would be reviewed for a possible EA requirement on a case-by-case basis.
These requirements will apply not only to new towers but also to construction that makes a “substantial increase in size” of a structure. That includes not only height but also tower width or the area excavated around the tower base. Substantial changes in tower lighting also would trigger these requirements.
Comments to WT Dockets 08-61 and 03-187 were due May 5. Here are some of the comments that had been filed as of April.
American Bird Conservancy,
Defenders of Wildlife &
National Audubon Society:
Millions of migratory and other bird species are killed at communications towers and related structures every year. … [S]tudies corroborate that there are population level impacts on many bird species and harm to endangered species caused by communications towers and related structures such as television and radio stations. Tower height, tower lighting, tower support structures (i.e. guy wires), location and lighting of related structures are all key factors in these bird kills. Each of these variables must be evaluated in terms of direct, indirect and cumulative impacts. …
Alternatives for constructing and managing communication towers can save birds without compromising the commission’s wireless communications mission or aviation safety. Reasonable alternatives to be studied include … requiring changes in lighting schemes to less impactful alternatives (e.g., turning off steady burning lights or at a minimum synchronizing blinking lights) whenever permitted by the Federal Aviation Administration; promoting collocation of antennas and shorter towers without guy wires; requiring heightened scrutiny for proposed towers in environmentally sensitive areas; providing guidance on lighting of associated structures; putting FCC personnel in charge of identifying and evaluating environmental effects of proposed towers instead of allowing tower registration applicants to do it; and adopting an interim approach to registering towers while the commission conducts its environmental analysis and proposes and finalizes revised rules for the ASR program. …
In 2005, the FWS [Fish & Wildlife Service] estimated that 4 million to 5 million birds are killed at communications towers each year. …
Lighting, height, support system and location of communication towers are key factors in bird kills at towers. The impacts — especially for neotropical songbirds — increase with overcast conditions or inclement weather. … Birds lose natural navigating cues and orient with the tower lights, circling the towers and eventually dying of exhaustion or collision with towers or support systems. …
As a FWS official noted: “Light appears to be a key attractant for night-migrating songbirds, especially when nighttime visibility is poor, cloud ceilings are low, fog is heavy, or various other forms of precipitation are associated with either passing or stationary cold fronts.” …
The role of aviation safety lighting is a critical factor to be studied. Aviation safety lighting for towers over 200 feet is controlled by the Federal Aviation Administration through its advisory circulars, which describe lighting styles and specify permissible styles based principally on tower height, and FAA policy guidance. … Towers with solid red lights (L-81Os) combined with flashing red lights (incandescent L-864s) cause most avian mortality, including nearly all mass mortality events.
Submitted by law firm Fletcher, Heald & Hildreth:
To date, much of the evidence presented to the commission has been anecdotal or undocumented. Those environmental and wildlife organizations who seek more rigorous review of tower construction (the “bird community”) have suggested that literally millions of migratory and other birds are being killed each year due to communications towers. … The suggestion that wild animals are being killed in large numbers is therefore something that, if true, would be of serious concern. In our experience, however, there is no factual support for this proposition, and the result is quite the opposite. …
NTCH’s personnel report that they never see any dead birds around the towers. Literally, none. Surely if millions of birds were colliding with the towers and dying there would be some evidence of carcasses at the base of the towers. … On the contrary, what we do regularly find are the carcasses of rodents which have been caught by the birds and eaten and their remains dropped at the foot of the towers. Many species of birds use the towers as roosting sites, so we frequently find towers with one or more large nests in them.
To be sure, we have heard of (but never personally seen) bird deaths associated with much taller towers than NTCH normally constructs or uses — guyed towers over 500 feet tall. While we are not sure ornithilogically why birds would strike those towers rather than shorter ones, there does appear to be at least some evidence of bird deaths there. It is also not clear why birds would fly into towers of that height but not buildings of similar height.
In any case, what is clear is that if there is a problem at all — and that remains an open question in our minds — the problem is limited to very tall structures. Towers of 300 feet or less categorically do not have an adverse impact on birds, and therefore no remedial measures or pre-screening of such towers for bird impact is called for.
It may also be that bird problems are limited to particular regions of the country or particular flyways that migratory birds use. If the facts bear that out, the remedy should be targeted only at those particular areas where the problem exists. Tower construction in parts of the country with little birdlife, no demonstrated problems or no migratory bird paths should not be impaired or delayed by measures that only apply in other regions.
U.S. Fish and Wildlife Service
Division of Migratory Bird Management:
The service appreciates the opportunity to continue working with the FCC, a relationship that was spurred by a large single-night kill of up to 10,000 Lapland Longspurs and other birds at four adjacent communication towers and a nearby, lighted outbuilding near Syracuse, Kan., in February 1998. …
The service now protects and manages 1,007 migratory birds. Each time a protected bird strikes a communication tower and is killed or injured, the collision represents an unpermitted “take” under the Migratory Bird Treaty Act. … While yet to be validated in wild breeding birds in North America, radiation from cellular communication towers in Europe is being documented as a problem for nesting birds, resulting in reduced recruitment, poor chick survivorship and mortality around cellular communication towers where nesting is occurring (Balmori 2005, Balmori and Hallberg 2007, and Everaert and Bauwens 2007). …
The impacts of communication towers on migratory birds have been reported in the U.S. scientific literature for more than half a century. Aronoff (1949) first reported several hundred migratory birds that were retrieved from a Baltimore, Md., radio tower in 1948. Later, Mayfield (1967) attempted to estimate nationwide bird-tower-collision mortality. During the 1970s, the service’s Bureau of Sports Fisheries and Wildlife raised upward the previous mortality estimates of Mayfield (1967) where Banks (1979) then estimated average annual mortality at 1.25 million birds/yr. This represented the best and most scientifically valid estimate of tower mortality at the time.
To update Banks’ FWS mortality figure, Evans (1998) and the service (Manville 2001a, 2001b, 2005) adjusted the Banks estimate to account for increasing numbers of towers since 1979, resulting in the service’s current estimate of 4 to 5 million birds killed/yr. at all U.S. towers. …
We specifically recommend the following:
— Avoid use of any L-810 steady-burning red lights on new towers being constructed, towers whose broadcast licenses expire and must be re-issued, towers being replaced and where L-810 side lights burn out (replace with strobe or blinking lights). Pending FAA’s update to their current (2007) lighting circular ��� which we are advised will occur in the near future — all L-810 lights should be extinguished and all L-810 lights should be removed as part of any retrofit.
— Use minimum intensity, maximum “off”-phased red strobe (or strobe-like), white strobe or red blinking incandescent lights with no L-810 sidelights. Use of red or white color and use of strobe vs. blinking lights were not statistically different in several previously conducted studies (Gauthreaux and Belser 2006, Gehring et al. 2009).
— Where new towers are to be constructed, or where repair or upgrade of towers will result in increased tower height, where practical attempt to keep towers under 200 ft. AGL in height, be of monopole or lattice design, and contain no guy wires and lights. This represents the service’s recommended “gold standard” and the environmentally preferred alternative for tower placement.
Donald G. Everist, P.E.
Cohen, Dippell and Everist, P.C.
Professional Consulting Engineering Services:
The undersigned is licensed as a Professional Engineer in the District of Columbia and has been in continuous employment with this firm or its predecessors for over 40 years. During these 40 years, he has been physically at numerous broadcast sites, often for weeks at a time. These site visits have been throughout the continental United States in various seasons and under different weather conditions. During this period, no birds were observed hitting towers or their guy wires. These towers ranged from several hundred feet in height to 2,000 feet. …
In the 1960s, all AM, FM and TV transmitter sites were manned with personnel during times the station was in operation. This practice continued for many years and there is no recollection of reports of bird strikes.
While the above observations are not a scientific study, it does support a conclusion that if this does occur, it is not a widespread event.
-- Leslie Stimson, Radio World
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