Dear all,
It would be fantastic if more people were collecting bird calls and depositing
good quality ones on pages such as these discussed.
It has been covered before, but I just want to point out that if you are to
record calls for distribution to others, you need to record in PCM (ie
uncompressed) format. If you choose a recorder that only allows compressed
formats such as mp3, for example, this creates very small files, but does so at
the expense of fidelity to the original sound. It is a complex process, but
essentially mp3 and other compressed formats use algorithms that 'chop out'
bits of sound that human ears cannot resolve (ie if two sounds are so close
together that the human ear can't resolve them, but hears it as 'one' sound,
the algorithm will essentially delete one). This saves space, but in terms of
archiving sounds for later analysis, this is not good news. The calls are
changed in a way that is impossible to revert. They sound fine to us, but to a
birds ear probably very different, and the things that we cut out may well be
important features that are used to define species, for example. It might also
make no difference at all, but the point is we can't tell.
So, if you simply want to record and listen to some sounds, than small hand
held recorders are fine. However, they won't yield calls that can be examined
in the way that Murray outlines below.
If you can afford it, Sennheiser microphones are great (I use a ME67 with K6,
but smaller mics would do, particularly for loud passerines), but as a rule any
mic plugged into a unit will yield superior quality than the on-board tiny
mics. Someone asked earlier about omni versus shotgun mics, if you are using an
omni-directional mic you'll probably need something like a parabolic reflector
to 'focus' the microphone onto what you're trying to record. These can be
cumbersome in the field, so I prefer to use shot guns with a simple foam wind
block over the top. Think of the difference as a bit like filed of view, omni
records over a very wide arc, whereas shotgun mic record from a much smaller
arc and are basically directional towards where they are pointed.
Lots of different options for recorders, I use Sound Devices (beautiful but
very very expensive) and Marantz PMD661 for hand held things. Note that there
are smaller, cheaper models, such as Microtraks, available, but the latter has
always introduced artefacts into the recording for the units I've tried, so
wouldn't recommend them. Edirol and Fostex are also well known and trusted
field recording brands in addition to Marantz. Lots of suppliers out there,
Wingfield audio in the states, Video Guys in Australia, shop around.
Recording gear is a bit like binoculars, everyone has a favourite. Some
standard requirements for mine regardless of brand: Record in PCM,with sampling
rates of 44.1kHz or 48kHz, 16 or 24 bit accuracy). Record some notes on
weather, behaviour and putative individual identity, and you'll be gathering
calls that sound great, but can also be used by anyone down the track.
There are general sites on what is required and so forth, so I'd also recommend
becoming familiar with what is around before buying if you are considering
this, but it can be a whole lot of fun...
Cheers,
Paul
On 22/08/2011, at 8:26 AM, Murray Lord wrote:
> A question was asked during last week’s discussion on sound recording about
> why
> birders should make more effort recording calls. Here are two examples that
> come
> to my mind of where more call recordings could impact on our knowledge of
> Australian bird taxonomy.
>
> First, the lurida race of boobook. At least one recent publications [Owls of
> the
> World 2nd edition by Koenig and Weick] treats this as a separate species.
> Yet the
> fieldwork that could establish whether this is the case has not been done in
> Australia. Sound is a part of this – the majority of changes in owl taxonomy
> in
> recent years have been based on calls. How many recorded calls are there of
> lurida
> boobooks to use as part of a taxonomic review? As far as I know, just two,
> one by
> Dave Stewart and one by Fred van Gessel. If anyone else is aware of other
> recordings, please let me know. Of course for such recordings to be useful
> it
> would be necessary to see (and ideally photograph) the calling bird as it is
> necessary to confirm the recording is really of lurida. Also it should be
> noted
> that calls don’t seem to vary as much between species in the Ninox genus as
> they do
> in some other owl groups.
>
> Second, Cicadabirds. The possibility of there being two species of
> Cicadabird in
> Australia has been discussed for a while [e.g. Glenn Holmes, The Bird
> Observer,
> 801; 12 (1999)]. While it has recently been suggested that this won’t be
> resolved
> properly without additional collecting of specimens [L. Jospeh, Emu 111(3) p.
> iii],
> given that calls are a significant part of the puzzle, more progress could be
> made
> if a lot of recordings were available to analyse. If a sufficiently large
> sample
> proved that certain call types were only heard in rainforest habitat and
> others
> only in dryer woodland then it would tend to support there being two species.
>
> I recommend www.earbirding.com as it has a lot of posts on calls of American
> birds
> and shows the sort of information that can be obtained from sound recording.
> For
> example, the calls of a recent vagrant sparrow were compared to recordings
> from
> various locations to see if the bird was from a migratory or resident
> population,
> which was relevant to the chance of it being an escapee. There are also some
> recommendations on equipment (see the equipment tab on the right side of the
> page).
>
> Murray Lord
> Sydney
>
>
>
> ===============================
>
> To unsubscribe from this mailing list,
> send the message:
> unsubscribe
> (in the body of the message, with no Subject line)
> to:
>
> http://birding-aus.org
> ===============================
===============================
To unsubscribe from this mailing list,
send the message:
unsubscribe
(in the body of the message, with no Subject line)
to:
http://birding-aus.org
===============================
|
