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The mysto thumping

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Jul 12, 2003
What is that weird thumping noise that I hear when diving in north county San Diego? It sounds like two rocks being banged together quite loudly, inside my head. I usually hear it with greater intensity when I am near reef outcroppings. Some say it is lobster, but sometimes it is so intense I cannot believe it. :confused:
Sounds like you're describing a noise that I've heard while diving of Ventura. Is it continuous at 2-3 second intervals? They told me that it was a sonic blaster for seismic studies but, you know Californians, they blame the oil companies for everything.
It is not a continuous sound. It's a "knock knock" and at no regular interval. I hear it mostly when I'm down exploring ledges or near the bottom. I usually only hear it in the shallows, 15' or less. I've never heard it deeper. The sonic blaster theory is a new one for me. Who knows... sometimes it is so loud it is startling.
WSB? I've never heard it when I see lots of wsb swimming around. ANy more info on that? Garibaldi might be the cause. This seems more likely to me since I see them all over where I hear the sounds and they are known to emit some sort of sound to warn interlopers. Me and my buddies will forever be arguing about this.
hey send some of those whites up here!

If the sounds are more of a loud "popcorn popping click" they're urchins and/or shrimp. If it's a couple of clicks every now and then and especially if you're peering under a ledge it's most likely lobstahs. If it's truly a "thump" it's a good chance that it's from a Black sea bass. They thump like jewfish when they get pissed off, but not in fifteen feet. A White sea bass has a sound more like a long "KRAACK!"

Gets me moist thinking about it. :inlove
Last edited:
...Auditory Hallucinations....

Welcome, Petrip74!
Yep, it is not something you are imagining: if it is the same 'munch-munch' type sound I hear when I'm swimming, I think it's the Garibaldi. Like: 'snap-crackle-pop!'
They were quite loud at Torrey Pines today in ---finally! ---much clearer waters. You probably saw the huge drifts of kelp that came ashore last week...?
I don't know if the small 'by-the-wind-sailor-jellies' (Vellela vellela) are a popular food source for fish, but those were coming ashore as well.
Diving two weeks ago we could observe some smaller fish nibbling on the kelp, and the crunching sounds were kinda loud.. [[chewing with mouths open!!!]]
Dolphins were scouting about two days ago as well....

Welcome to the neighborhood, and if you want to do a shore dive, gimme a post!

Great info! Thanks. About the big "thump thump" pounding rock noise- black sea bass is the most resonable explanation yet. Although I hear it in shallow water, the area that I'm talking about has a big one we see rarely. It is magnificent, calm, and struts his stuff around there. It seems only it has the mass and demeanor to generate that powerful sound. If it is indeed him/her, I'm glad to know she is staying right out of sight for the most part- good habit and more special when sighted!
These California waters are noisy!

I was diving at Crystal Cove two days ago (w/ Roan at one point) and heard lots of that popcorn sound. Today I was diving at Salt Creek (vis sucked) and there was a sound that was a rapid burst "tick-tick-tick-tick" that occurred every few seconds. I managed to record the sound with my camera while I was filming. I could post the recording if anyone is interested in trying to identifying the sound

BTW, how does one avoid getting wasted by maniacal jet-skiers when attempting to get out to the Salt Creek kelp beds?
Fish database with sounds!

Hi Pezman,

the university of Kiel (Germany) hosts an online-database of fish. In this database you will find everything you ever wanted to ask about fish (and more...)
I personally don't know anything about fish, but if you mean by black sea bass "Centropristis striata" (and not "Stereolepis gigas") then you are lucky and they even have two sound files of this fish. Now ain't that cool?

This is the link for the black sea bass:

And this one gives access to the two sound files:

Let us know, whether that's what you heard.

Re: These California waters are noisy!

Originally posted by Pezman
there was a sound that was a rapid burst "tick-tick-tick-tick" that occurred every few seconds.

BTW, how does one avoid getting wasted by maniacal jet-skiers when attempting to get out to the Salt Creek kelp beds?

a) The ticking is urchins.
b) Tow a bouy with a flag and pray.
As I was reading these threads...I was in stitches cause I was trying to imagine people mimicking the noises they've heard..thanks for the laugh.:D
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