On 11/18/97 17:01:36 you wrote:
>
>> 1. In relation to the discussion of using bird tapes. Are there
>> studies (with specific evidence) which demonstrate damage due
>> to using tapes? Is there substantive theory which suggests harm
>> might be caused? References?
>>
>Yes, I believe such studies exist, where birder densities are higher
>(USA, UK), but no, I don't have the reference(s).
To my knowledge, there has been no study demonstrating damage to birds from
tape playback in
the U.S. For many years I have been urging critics of bird recording and
playback to conduct a
controlled study of the following sort: Pairs of common breeding species in
similar habitat would
be banded. A commercial tape of one or two songs of the species would be
played periodically
from a spot in one territory, while no tapes would be played in the other
territory. The reactions
of the study pair to playback would be noted, displacement of banded birds by
floaters in either
territory would be monitored and the floaters banded for ease of reference, and
the breeding
success of birds in the study and control territories would be compared.
I am a bird recordist, and find playback essential to collect a variety of
vocalizations, including
alarm vocalizations that rarely are given or heard, and to lure some species
close enough to lower
the record level for high quality recording and attract unidentified calling
birds so that they may
be identified. When I am collecting tapes, I often will play back each
successive cut to see if I
can provoke a different, possibly more excited response, thus gathering as many
different
vocalizations as possible from a particular bird.
Most birders who use canned tapes to attract a bird into view play one or two
cuts that never
vary. Sometimes such limited tapes can provoke a highly excited response, but
they often have a
modest impact on the subject bird, which pops out for a look, then fails to
respond further.
I'm not aware of any case in which a bird is known to have been driven off
territory by tape
playback. Indeed, some vagrants in the eastern U.S. have been bombarded with
tape playback
day after day, yet continue to respond and remain at the stakeout site for
extensive periods.
The educational and conservation benefits of using tape playback to attract
birds are obvious. I've
shown birds to people who never would see them by using tape playback, or by
whistling calls or
squeaking. If they can see it, they are much more likely to care about its
welfare. Also, I think it
is preferable for large bird tours to call in individuals of needed species
using playback, keeping
the group on a trail, than for the tour participants to fan out off trail
looking for the birds.
Without asking the membership's views, the American Birding Association adopted
a "Code of
Birding Ethics", written by a board member who supported the recent firing of
Paul Lehman, the
highly regarded Editor of Birding. (The members were not consulted about the
disgraceful
sacking of Paul either.) The "Code of Birding Ethics" includes the following
passage on the use
of bird recordings:
"Limit the use of recordings and other methods of attracting birds, and never
use such methods in
heavily birded areas, or for attracting any species that is Threatened,
Endangered, or of Special
Concern, or is rare in your local area."
While I think it is desirable to limit the use of recordings in heavily birded
areas where playback
is likely to be heard by other birders, there is no evidence to suggest that
using recordings has any
adverse impact on birds in such areas. Similarly, there is no evidence to
suggest that using
recordings to attract rare, threatened, or endangered birds is detrimental to
them. Indeed, more
recordings are needed of most birds in those categories. If bird recordists
are unable to approach
the birds with their equipment and to use playback when collecting recordings,
the opportunities
to add to the libraries of bird sounds will be lost. It's fortunate that the
Green Police weren't
around in 1954 when Stuart Keith taped the last vagrant Bachman's Warbler in
northern Virginia.
That tape is the only recording of the species, which has not been observed for
many years and
may be extinct, presumably due to wholesale habitat destruction in the
southeastern U.S. and
Cuba.
While the "Code of Birding Ethics" specifically condemns some use of tape
recordings as
"unethical", it takes no position on bird banding (ringing). Yet many, if not
most, bird banders
are listers themselves (e.g., banding vagrant birds for an individual's life
list of birds banded), the
scientific necessity of much banding is highly questionable, and even the most
careful bird banders
kill birds. I've never killed a bird by tape recording it or playing back the
tape, and am not aware
of anyone else having done so.
Furthermore, watching birds disturbs them, except where birds are exceptionally
tame, as at
O'Reilly's. In places such as Irian Jaya, where small birds are relentlessly
hunted for food by the
natives, the mere presence of a human causes substantial disturbance to most
species in the
vicinity. If any disturbance of birds is deemed to outweigh the educational or
scientific benefits
of the observation method causing the disturbance, bird watching would have to
be prohibited
almost everywhere.
There may be no species of wild bird for which every vocalization has been
recorded.
Furthermore, many species endemic to Africa, Asia, and Latin America have not
been tape
recorded at all, or their vocalizations are poorly known from very few,
fragmentary recordings.
Thus, I think it would be desirable to encourage more birders to take up tape
recording (as soon
as possible, in view of the acceleration of deforestation in every country and
the human
population explosion), in the hope that a few may become seriously interested
in filling the
substantial gaps in the major collections.
John Wall
New York
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