Signal Processing HELP wavread, wavwrite, fft!!

I want to cut portions out of my .wav file and save them as separate .wav files, but I have no idea how to do so, and I have about an hour of data so I need to make a loop that will cut proportionally, but the sounds happen at different instances so I might have to do 1 by 1.

Here is my code so far:

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N1=1; N2=4410;
[wave,fs]=wavread('insectuno.wav', [N1 N2]);
siz=wavread('insectuno.wav','size');   
sound(wave,fs);
t=0:1/fs:(length(wave)-1)/fs;
plot(t,wave);
figure(1);
    plot(t,wave);
    title('Wave File');
    ylabel('Amplitude');
    xlabel('Length (in secs)');
n=length(wave)-1;
f=0:fs/n:fs;

wavefft=abs(fft(wave));

figure(2);
    plot(f,wavefft);
    xlabel('Frequency in Hz');
    ylabel('Magnitude');
    title('The Wave FFT');

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[Walter Roberson]

Is the question about how to write a portion of your "wave" array to a new .wav file? Or is your question about how to determine the boundaries of where to cut?

wavwrite( wave(LowerBound:UpperBound, :), fs, NewFileName );

With respect to determining where to cut: you did not indicate anything about what kind of boundaries you were interested in. For example, is your goal to cut out the commercials from a talk radio show?

[Dante]

I need both, to write a portion of my "wave" array to a new .wav file and to determine the correct boundaries to cut.

These are noises from insects flying through a sensor and I need to separate each insect noise.

Thanks!

[Walter Roberson]

Does a perio diagram show anything interesting when an insect flies through the sensor? Or is the input just low level noise when there is no insect, such that even a signal amplitude test might be useful?

[Dante]

Do you mean the plot? It shows a lot of peaks, and that's where most of the insects are. But I don't know how to cut them at the right point.

And yeah there is very low level noise when there is no insect.