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Telecommunications Towers Affect Avian Community

Received the following mail concerning Bird Kill rates reported in association with transmitter towers. It's not just humans that are being negatively impacted by this frenzied build-out of Telecommunications Technology. Once these Towers are all built, it will be too late for common sense planning ...

Date: Tue, 17 Feb 1998 00:57:47 -0500
To: bill@ornith.cornell.edu
From: Bill Evans 
Subject: 150 pounds of Longspurs


An estimated 5000-10,000 birds, mostly Lapland Longspurs, were killed on
the night of January 22nd, 1998 in the vicinity of a 420 foot tall guyed
communications tower in western Kansas.  Apparently there was a heavy
snowstorm which put the birds up at night looking for bare ground, but 
unfortunately a dense fog occurred and the huge disoriented flock circled the
lighted tower and were slaughtered in collisions with the guy wires.  Since
I know some of the folks out there, I dug up a little more info about the
kill.  In a two day period, people salvaging the kill picked up about 150
pounds of dead Longspurs and many more were left behind.  A few Horned
Larks, one Chestnut-collared Longspur, and a Dark-eyed Junco were also
found.  Longspurs were also found dead in nearby wheat fields.  Some were
impaled by wheat stubble suggesting they were so disoriented by the lights
and the fog that they didn't even know which way was up and flew into the
ground with full force.  The tower had three flashing white strobes.  This
is interesting because it has been suggested that white strobes cause less
mortality than blinking red incandescent lights.  There were also power
lines and a lighted pumping station, some other smaller towers, buildings,
and fences that evidently contributed to the mortality.

This event brings up the important question of what the accrued impact of
the rapidly increasing number of 200+ foot high communications towers
across the continent are having on our birds.  An estimate in the 1970s put
the total at 1.2 million per year (Banks, 1979).  But even since 1989, the
number of such towers in New York State has doubled and many communities in
central New York are now wrestling with tower siting and minimization
issues.  We have nearly four times the number of towers today across the
continent as we did in the 70s and there is evidence that somewhere between
2-4 million songbirds are incidentally killed every year.  Most studies of
tower kills have been done at the tall 1000+ foot towers.  The most famous
such study was initiated by Herbert Stoddard at the Tall Timbers Research
Station near Tallahassee, Florida.  Over a 30 year period the annual kill
averaged about 1600 birds and carcasses were found under the tower nearly
every day from August through November.  In New York State, studies at tall
towers have been conducted by Wilifred Howard (25 year study at an 850 ft
tower in Elmira) and Arthur Clark (31 year study at a number of 1000 foot
towers around Buffalo, NY).  These studies, conducted only in the fall,
averaged hundreds of birds per year with peak years in the thousands.

Though it is generally agreed that towers under than 500 feet high pose less
threat to migrating birds, the massive Longspur kill noted above shows that
large kills sometimes occur at smaller towers too.  This is alarming
because these shorter towers are rapidly proliferating and there are no
long term studies on this size class (that I am aware of) so it is
difficult to assess their accrued impact.  Significant kills occur when
specific cloudy/foggy weather conditions overlap with peak migration
nights.  The flashing lights (on towers over 200 feet tall for aviation
safety) reflect off the water in the air and form a "room" of light causing
birds to switch to their diurnal (visual) mode of navigation.  They end up
circling the tower and colliding with guy wires, other structures in the
vicinity, and other birds.  The location of the tower with respect to
regional geography and migration patterns plays an important role in
determining a particular towers kill potential.  Any guyed and lighted
communications tower over 200 feet can kill birds if the conditions are
right.  I'm not aware of specific long term studies for towers in the
200-300 foot range but there are numerous studies indicating significant
annual kills at lighthouses in the 200-300 foot size class.

As if the problem with the short towers isn't enough, even more alarming is
the likelihood that within the next ten years we will have 1000 new tall
towers in the 1000+ foot range built across the continent to broadcast the
new digital TV medium (see Smithsonian, July 1997).  Yes, terrestrial TV is
likely to compete with the satellites for a long time to come.  Once
companies have invested money in these towers, they will lease space on
them for a variety of communication services.  Tall towers are the most
economical way to broadcast over a large region and many of the existing
tall towers are already loaded to the max with antennas.  So broadcast
companies will be building lots of new tall towers.  Based on the evidence
that exists today, these towers alone will likely add another million
songbirds to the annual towerkill toll.  Along with all the new shorter
towers, it is not far fetched to predict that annual tower kills across
North America will soon exceed 5 million songbirds a year.  How does this
compare with the impact of 70 million cats and the continuing degradation
of natural habitats?  Well if every cat ate one songbird a year, the
towerkills are a lot smaller, but towerkills are a source of mortality that
we can reduce by encouraging environmental site reviews before tower
construction, by keeping tower numbers to a minimum, and their heights as
low as possible.

There is a Bill currently before the New York State Assembly called the
Bragman Bill (Assembly Bill 8567).  This Bill proposes a "wireless facility
siting act" and though it is still evolving, it theoretically could give
municipalities in New York State more authority to control and restrict the
siting of communication towers.  Currently section 704 of the Federal
Telecommunications Act preserves local zoning authority, but it also
provides for the restriction and preemption of such authority by the
Federal Communication Commission [FCC].   So, to give a local example here
in New York State, Frontier Cellular applied to the town of Ulysses to put
up a 280 foot guyed and lighted cellular communications tower.  In response
to public sentiment against a lighted tower, Frontier voluntarily proposed
a 195 foot tower that would not have to be lit.  A group of concerned
citizens believed that equal or better coverage could be obtained by
co-location on two existing structures (a water tower and fire tower), so
they urged the Planning Board to reject the application.  Frontier claimed
it would be too expensive to cover the cell from two locations instead of
only one.  At public hearings the citizens group argued against approval,
and engaged both technical and legal expertise to provide supportive
evidence for a denial.  Their foremost argument was that Frontier had not
demonstrated that the tower needed to be built; an engineering consultant
employed by the citizens proved that, in a way consistent with the Ulysses
Tower Ordinance, Frontier could utilize two existing shorter towers to
accomplish the same coverage.  Frontier agreed but noted the extra cost of
additional transmitting gear and said that it couldn't afford to be the
first cell company in the area to spend more for environmental and
aesthetic reasons. When it appeared that the Planning Board might respond
to the citizens group evidence and deny the application, Frontier
threatened to sue the town for extensive damages.  In the face of this
threat the Planning Board backed down and approved the application.  The
concerned citizens have continued their opposition; on the basis of their
arguments presented at earlier public hearings, and other procedural flaws
in the application process, these citizens have filed suit in the State
Supreme Court against the town Planning Board, the Board of Zoning Appeals,
and the Building Inspector, and against Frontier Cellular, asking for
reversal of the town's action.  The point here is that birders in New York
State could potentially help shape the Bragman Bill to empower towns such as
Ulysses to minimize aesthetic and environmental damage.  This would include 
giving the towns legal backing to minimize the number and height of towers
and, therefore, concurrently reduce annual bird mortality.

Since there currently are no well defined guidelines in place by the United
States Fish and Wildlife Service's Office of Migratory Bird Management to
minimize the impact of these towers on migratory birds, the responsibility
may initially have to lie within local municipalities to enforce minimum
environmental impact.  By getting involved with the evolution of the
Bragman Bill, it appears we can at least give municipalities the potential
for reducing the number and height of communications towers.  There is a
public hearing on the Bill on March 11th in Albany.  Folks in the Ithaca
and Cortland areas can contact their Assemblyman Marty Luster (125th
district) for more information regarding this Bill.

On the Federal level, the FCC issued a proposed rule on August 19th 1997,
MM Docket No. 97-182, which would preempt the application of State and
local zoning and land use ordinances.  This rule was proposed in order to
help speed the construction of the tall 1000+ foot digital television
towers through the siting process. Folks in Vermont have taken the
lead on reducing the height and number of communications towers, among
other reasons, to preserve the beauty of their landscape.  Vermont Senators
Leahy and Jeffords introduced a Bill (S. 1350) on October 30th 1997 to
counteract the FCC rule and preserve State and local authority to regulate
the placement, construction, and modification of certain telecommunications
facilities, and for other purposes.  Currently the FCC has backed down but
this issue still needs watching.

Many cell communications companies have been building their own towers
instead of co-locating transmitters on a shared single tower, the way cable 
TV electric power and phone lines share telephone poles .  This means we 
could end up with two to three times more towers than needed to do the job, 
and a larger unnecessary mortality on the already threatened songbirds
we appreciate in our gardens and woodlands. Bird lovers across the
continent need to take the lead on minimizing the number and height of
towers in their regions.

Bill Evans
Cornell Lab of Ornithology
159 Sapsucker Woods Road
Ithaca, NY 14850
bill@ornith.cornell.edu

...........

Lit. cited:

Banks, R.C. 1979. Human related mortality of birds in the United States.
USFWS Spec. Sci. Rep. Wildl. No. 215.

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