Just the wind.
1 seconds sound clip from the Attack of the Crab Monsters (1957) movie soundboard.
You can hear this line at 00:13:40.984 in the DVD version of the movie.
Quote context
[...]
- You would know better than I. But why, I ask, did the writer stop in the middle of a sentence?
- Yes, why, Karl? Unless something really unusual happened, I'm sure he would've finished.
- Well, Jim and I will head down to south valley in the morning.
- You know, I haven't seen any insect life since we arrived.
- You nearly frightened me to death.
- Well now, I couldn't very well announce myself underwater, could I?
- Besides, you looked scared down there.
[...]