From: "oryoki2000" <>
>
> Leo Boon wrote:
>
>>> ..I am looking for player and speakers
>>> which will [attract] wanted species...
>
>
> Dear Leo,
>
> The subject of field playback is very controversial. At a minimum
> you need to be aware of any local regulations regarding playback.
> Playback is prohibited in more places than you may realize. Most
> national and state parks in the USA regulate sound playback. These
> regulations protect species that might otherwise be subject to
> harrassment. Regulation of playback is especially important
> in "hotspots" (inside or outside parks) where an unusual species can
> be found, or where birders congregate (such as near a wilderness
> lodge). Many sound recordists "just say no" to field playback at any
> time.
>
> That said, I understand the value of playback when doing census work,
> or when trying to show an unusual species to a group. It's far less
> damaging to the environment to attract a bird over to your location
> than it is to make a new trail into the forest.=20
A lot of the playback controversy is based on the assumption we know
what the emotions of some animal are. That is a major error well known
to those that study animal behavior (that study has a name, Animal
Ethology). It was about the first thing brought up when I took courses
in this subject. Playback is a area where otherwise fairly logical folks
yield readily to the Bambi syndrome.
It is just as easy to make the interpretation of a excited male
responding to playback as building up his ability to ward off other
males, building up his hormones as it is to think that he's being
discouraged or confused. Used in moderation we are probably doing no
damage. It is clear if you keep at it in the same area you can probably
do harm to the dynamic of the established territories. That is the
reason for many of the specific off limits areas. Other regulations are
directly from someone under the influence of the Bambi syndrome. And
it's easier to just blanket outlaw something than to look closer and
limit it just where necessary.
It is also fairly well known that you cannot trust any vocalizations you
get to be natural. So doing it so you can record is a bad idea. At best
you should use it only to find locations and come back in a day or two
without playback to try and record. For the most part, it will only
attract males actively defending a territory. Or in the case of frogs,
ones in breeding mode and inclined to sing.
The least expensive tool of this type is the Audobon Society "birdcall".
This consists of a piece of wood with a metal rod loosely through it.
You twist the rod to make various noises by it's action on the wood. You
are attracting mostly by using a animal's curiosity, it's a strange
sound. In the hands of experts I've seen very impressive use of this
tool with many animals coming into view, not just birds.
Playback is a standard tool used in science. I use playback both playing
recordings and my own poor vocal imitations of the call of the Pine
Barrens Treefrog in my continued search for it in Georgia. In fact I
just recently bought a amplified speaker for this. Not much help in what
to buy, as it's way out of production, it's a Toshiba "Miniamp" speaker
system I got for next to nothing off Ebay. About the same size as my
Portadisc, it's from the days when circuits were made from individual
transistors. Very convenient, runs off 8 D cells, has a mic with it as
well as inputs for other sound sources. The 8 NIMH batteries I got cost
far more than the Miniamp.
I have no illusions about the coverage of such a speaker system, though
it's rated at 100 yards. The way to evaluate that is start it playing
and walk out and see how loud it really is. The falloff is dramatic. On
anything you can run off batteries don't expect a lot of distance. In my
case that's not a big problem as I only test specific locations and
those can only be identified by being right at them.
In the Pine Barrens area in Florida they were known from three sites and
were considered very endangered after several years of regular looking
had turned up no more. By the use of vocal imitations and playback it
was found in several hundred sites across several counties in one season
in a successful effort to get it off the endangered list. Pine Barrens
Treefrogs have a calling pattern that makes it very hard to survey them
just by listening. They form into "calling groups" of just a few
individuals, often several calling groups in a area. Typically only one
calling group is active at a time. They call for a few minutes, and then
are silent for 20-30 minutes before repeating. For survey that means you
could, at best, check out just a few sites in a night, and their entire
calling season is only a few months. They will, however, readily respond
to even crude imitations of their call.
Walt
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