Noisiest could mean a few things including:
a) the calls which reaches the highest power
b) the calls which contain the most energy
c) the calls most easily detected by a human in certain ambient conditions
d) the calls most easily detected by a conspecific in certain ambient
conditions
e) calls which propagate furthest in a certain environment
and it matters which you are talking about.
Uperoleia lithomoda is a small (~25mm long) Top End frog. Its call is
a click like two pebbles colliding. The (short-term) power reached by
its call is the highest of the (few) measurements I've seen for frogs.
My back-of-the-envelope maths suggests its 10x that of a crowing rooster.
Its possible for a tiny animal to produce this power because does it
only for a very short time - 0.02 second, hence the (total) energy in
its call is much more modest.
Someone suggested Sulphur-crested Cockatoo as the noisiest bird.
Its broadband chaotic calls must contain a lot of energy but they won't
be as easily detected at distance as narrow-band calls such as whistles.
Small choruses of frogs can be heard by humans at over 1km so I'd bet
some bird can be heard at that those distances too. A Powerful Owl call
must be audible at considerable distance in quiet conditions.
Andrew
--------------------------------------------
Birding-Aus is now on the Web at
www.birding-aus.org
--------------------------------------------
To unsubscribe from this mailing list, send the message 'unsubscribe
birding-aus' (no quotes, no Subject line)
to
|
