Checking the stomach contents...

Ken Jones

Staff member
Acouple of old threads on checking the stomachs…

Date: January 26, 2002
To: PFIC Message Board
From: SD Fisherman

Subject: Does anyone else do this? Eeeeeeewwww!!!

I know this might sound gross, but do any of you examine the stomach contents of the fish you're filleting? My dad taught me to do this years ago. It's educational in that you can get an idea of the diet of different classes of fish. For instance, the big opaleye I caught yesterday, that struck a squid strip, had a lot of red seaweed in its stomach. A barred sand bass (12.5”) that I caught under a school of ‘chovies in summer 2000 had 13 ‘chovies and a crab in its stomach! (Boy was he a fattie! I thought he had a tumor at first...) One sheephead I caught had part of a lobster leg, etc. in his gut. Anyone have anything to add???

PS: Part of this education was also teaching me of the dangers of eating cabezon roe. I should stop being so lazy and research this myself but does anyone know offhand exactly what it is about the roe that makes it so poisonous? Thanks in advance.

Posted by Mikey

Nah — I do it all the time... smart fisherman do as well. Examining the contents of a fish's stomach only proves what he's been eating — thus, you know what to use for bait.

Posted by neptune1234

I always check the guts of what I catch. Heck that’s half the reason I keep fish. Amateur marine biology is my specialty. The last sturgeon I caught had about a pound of grass shrimp in it along with two bullheads and a baby kingfish. I caught a leopard shark once that had a hook and bait that I had lost a night before still rigged in its stomach. I noticed that the skates at McNears Pier normally have a few 2"-3" rock crabs in their stomachs along with baits that have fallen off the hook. Hatchery trout always have rocks from off the bottom in their stomachs. A 16” smelt I caught up in Bodega had a rubber band in its gullet. I got a clam pearl out of a Washington once. Of course there’s the whole JONAH thing. I heard Christians taste better than...well... kingfish… hehe… don’t laugh you might get a ticket. No fun zone you know… lol......Fish ON!

Posted by Ken Jones

Cabs & crabs... 100%, every last one of them, that's the percentage of cabezon taken by me in the Point Arena area that had small crabs in their stomachs (I always check). Yet almost no one seemed to fish for the cabezon with crabs. Instead, squid was the preferred bait along with shrimp or abalone trimmings.

Posted by Songslinger

Cabs & crabs... Too true. In fact, one of the best cabbies I got (just south of Pacifica) was taken because it slammed the crabs that were feeding on the cut anchovy I had on my hook! Talk about fool's luck.

Posted by Songslinger

Always! I believe it makes me one better angler to examine the innards of the fish he keeps. You can spot both short and long range trends and variations. The same species may have markedly different contents than another in a different location. This has helped me determine what bait to bring, how to specialize my fishing and tailor it to a given area.

Posted by Red Fish

All the time.... and almost every time it seems like the fish have been feeding on something other than what I served them. It makes you wonder when some people tell you that the fish are “only” biting on a particular bait. Maybe it's not what you serve sometimes but rather how you present it that counts.

Posted by Ken Jones

Perhaps a little fishy haggis matey?

Posted by illcatchanything


Posted by drudown

I noticed the striped bass I catch out on Berkeley and San Pedro have small anchovies in them. The ones I catch in the Delta are stuffed with several grass shrimp. Trout I catch always have Berkeley Powerbait and power eggs in ‘em. Jacksmelt always have anglers’ leftover baits.

Posted by Rock Hopper

LMAO! I LOVE this — Compliments of Mikey: “Nah — I do it all the fisherman do as wel

Posted by Ken Jones

Muddled and bewildered syntactics?

Posted by riorust

"smart fisherman do as well"

Posted by sd fisherman

Ok, I admit, that was dorky… not the subject, just the geeky punch line. HAD to have been from 2002 lol.

Date: July 20, 2004
To: Pier Fishing In California Message Board
From: sethook

Subject: After gutting your catch

It would be superb if everyone inspected the guts/stomach of their game fish keepers/catches, so that we could be enlightened on the feeding behavior of fish. Just a thought. Thanks to RedFish for turning my attention to this when he mentioned inspecting the guts of a keeper leopard he caught before, and this way he found the best bait for leopards, and I bare witness. Two fat 4 1/2 leopards landed in less than a 2-hour period of time, on the same bait. While live smelt and squid didn't produce as well!!!I think this might be a secret, so I better not say or he might get mad. I am sure a lot of you already know anyways, but I was just really impressed..

Now go get that fat one and cut it's stomach open if you decide to keep it :)

Posted by calrat

All my rockfish species seem to LOVE crabs. I always cut the stomachs open to inspect and always find a crab or two in there.

Posted by Ken Jones

Same with North Coast cabbies. You're right, it's always good to check the stomach to see what the fish are feeding on. However, don't limit yourself to just that local food when determining your bait. Fish are opportunistic feeders that feed on food that is readily available and sometimes, when several anglers are fishing an area, and tossing out bait, the fish will change their eating habits to reflect the new food that is available.

Posted by fishingrod

I agree Ken, I once gutted a mack to use as bait and found a chicken wing bone in its stomach.

Posted by dompfa ben

I caught a perch that paid off like a slot machine. A 1.5# barred surfperch that had a quarter and a dime in its stomach. Must have been attracted to the flash of some kid's ice cream truck money. What was surprising was that it swallowed it. Now, if I can find that Ancient Sand bass with the gold Pieces of Eight in its gullet...

Posted by dompfa ben

My favorite legend from a fish's stomach...Has got to be the one my dad told me as a kid, a tale shared with him and my mom on their honeymoon by a charterboat captain. Apparently, a newlywed couple, very much in love, decided to take an afternoon cruise on a sailing ship off the Kona coast. Much to the delight of the groom, the package included a chance to catch a big Hawaiian bluewater fish on the troll. Without warning, the weather picked up considerably. While the crew attempted to bring down the mainsail, a gust of wind swung the beam towards the newlywed bride. As a reflex, she threw her hand up in front of her face as she ducked out of the way. Luckily, the beam glanced off of her left hand, but to her great dismay, she discovered the blow had knocked her engagement ring off of her finger.

The bride was reduced to tears, clinging to her husband as the squall passed. While the financial loss was great, both were saddened at the loss of something so emotionally valuable. The sailboat headed for port, and the captain offered to buy the couple dinner as a mild consolation.

About 20 minutes from port, one of the trolling rods starts zinging "ZZZZZZZZZZZZZZZZZZZZ!" "Number three! Number three! It's your rod, let's go!" shouted a crew member. The heartbroken husband jumped to his feet, threw on a rod belt, and took the rod as a bull dorado danced across the surface of the cobalt seas.

It was a short fight on the heavy trolling gear, and the fish was brought to gaff quickly. The captain, still trying to placate the saddened couple, offered to have the fish cleaned and prepared for their dinner. Back in port, the mahi mahi was filleted and sent to the kitchen. As the knife passed through the second side of the fish, the crew member charged with cleaning the beast heard an unfamiliar "clink" on the blade. Upon further investigation of the stomach cavity, the crew member was amazed to find the woman's engagement ring. The ring was returned to the couple at dinner, and both of them were awestruck at what they considered a miracle. The Moral of the Story: "Ladies: If you want jewelry, it's best to let your husband fish."

Posted by 2d

Isn’t' a standard kokanee trolling rig called a "wedding ring"?

Posted by scooterfish

Fly fishermen have been pumping the stomachs of freshwater trout for a long, long time for this very reason... matching the hatch is a critical component of fishing success no matter where you are, be it with natural or artificial baits. Scooterfish



Well-Known Member
Interesting stuff
Here's a couple stories:
At my most recent trip to Avalon, I was using big chunks of mackerel (like half a 7 inch mackerel). I kept on getting short runs that pulled the clicker, but didn't connect. Later when I switched to strips of squid on a light dropper loop, I caught a couple 12~13" whitefish. One that I kept had a chewed-up but still mostly whole back half of a mackerel sticking out of its throat. I still wonder how it managed to choke that huge chunk of bait down without getting hooked. That same trip, I also caught a ~20" calico with a scrap of rockfish skin in its stomach.

The second triggerfish I caught from the Cabrillo Mole had a size 10 Eagle Claw baitholder attached to a snelled line lodged inside its stomach. Interestingly it took a big chunk of mackerel (see a trend?) on a wire leader with a 5/0 hook. How it managed to fit such a large bait and hook inside of that tiny mouth is beyond me.

Of course off both Avalon piers, perch and even calico and sheephead are often stuffed full of green peas and fish food used to chum. On occasion even the mackerel and scad (especially the bigger ones) have peas in their stomachs.

On the mainland, I've caught spotfin croakers with the remains of spiny mole crabs (Blepharipoda occidentalis) inside their stomachs. Guess the spines, claws, and hard shell don't stop them from being eaten. Jacksmelt, as noted above, almost always have chunks of stolen bait inside their stomachs.


Well-Known Member
I like the oddball things found in fish stomachs. I caught 3 cabezons between 6 and 10 lbs on a trip out of port san luis a couple of years ago. Since cabs are not allowed to be filleted on boats the deckhand said he would fillet them back at the dock. When we got back to the dock he told me to watch when he filleted them. He said 50% of the cabs he filleted had rocks in their stomachs. Sure enough 2 of the 3 cabs had small marble sized rocks in their stomachs.


Active Member
A couple of times I caught large spotted bay bass with kind of hard uninteresting brown oval things. It kind of looked like something a plant would grow out of, like little potatoes. Lol I didn’t know what they were and didn’t want to find out. Just chucked them overboard.


Well-Known Member
A couple of times I caught large spotted bay bass with kind of hard uninteresting brown oval things. It kind of looked like something a plant would grow out of, like little potatoes. Lol I didn’t know what they were and didn’t want to find out. Just chucked them overboard.
I find those all the time in sand bass and shallow-water rockfish. I'm not sure what those are either.


Well-Known Member
I’m curios now. Maybe sea cucumbers? I’ve seen razor clams in their bellies. Mistaken identity? More fiber in their diet?
As far as I can tell they are not the right size or shape for sea cucumber ossicles. I've been poring through a couple of research papers and as of now I cannot find anything so far with remains that resemble what we've been seeing.