Chumming for Halibut: The #1 Strategy Most Anglers Ignore
Chumming for Halibut: The #1 Strategy Most Anglers Ignore
If you’ve ever dropped anchor in the San Juans or the Salish Sea hoping for halibut and ended up just staring at your rods, waiting... and waiting... only to come home empty-handed and wondering what went wrong, you’re not alone. You might have the right bait. You might be sitting on a good spot. But if you’re not chumming effectively, you’re probably just fishing with the volume turned way down.
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The Wake-Up Call That Changed Our Halibut Fishing Process Forever
Our best halibut days have one thing in common: chum.
Long before Scott and I fished together, we both had memorable experiences that pointed to one truth—scent matters more than most people realize.
My first breakthrough came over 10 years ago during one of my earliest halibut trips. A thick fog had rolled into Burrows Bay, making it unsafe to reach our intended fishing spot. We didn’t want to call it a loss, so we reached out to my ex’s uncle—a seasoned commercial shrimper. He told us, “The fish follow the scent,” and shared the coordinates to one of his active shrimp pot sets not too far from where we were. With few options, we anchored up nearby at a spot that looked productive for halibut, dropped down a salmon head in our chum bag, and hoped for the best. A few hours later, I was standing over a 52-pound halibut. It was unexpected, totally unrefined, and absolutely unforgettable.
Scott’s lightbulb moment came after years of fishing halibut without a solid chumming plan. On one trip, he brought along a thrown-together bucket of leftover shrimp bait—a pungent mix of cat food, herring, and various oils. They anchored on a familiar bank in 90 feet of water and fished for a while with no luck. Then he dropped the chum bag. Within 45 minutes, they landed three halibut. Everything else—location, bait, tide—had stayed the same. The only variable that changed was the scent in the water.
Both moments, years apart, pointed to the same truth: the scent made the difference.
One evening Scott and I were swapping our best halibut moment stories when we both realized something powerful: our favorite halibut fishing memories had one thing in common...shrimp bait.
Now, we don’t drop anchor without a chumming strategy. Because when you combine the right spot with the right scent—you don’t just fish harder. You fish smarter.
The Science Behind It
I’m a science nerd. I like to dig into data and understand the "why" behind how things work.
Here’s my theory: the more I understand how something works, the better I can apply it—and the better my results on the water. That’s what led me down the rabbit hole of halibut scent detection. I didn’t just want to know that chum worked—I wanted to know why it worked. What makes halibut so good at finding food, even when they can’t see it?
It turns out halibut are scent-driven predators with an olfactory system that’s up to 100,000 times stronger than ours—comparable to salmon. They don’t need to see your bait to strike. They just need to smell it.
Their olfactory system includes:
Nostrils (nares): Pull water into sensory chambers
Olfactory rosettes: Packed with cells that detect chemical signals
Olfactory bulb: Processes those signals and tells the brain “that’s food!”
Why This Matters for Chumming: Halibut can detect specific amino acids like alanine and glycine in concentrations as low as 10⁻⁷ M. These are the same compounds that oily, protein-rich baitfish release into the water as they break down. When those compounds hit the halibut’s olfactory system, it triggers a feeding response—even if the fish is hundreds of feet away.
So I started asking: which baits contain the highest levels of alanine and glycine?
That’s where science really backs smart fishing. Amino acids are the building blocks of protein—and more protein and oil mean more scent. The top bait choices for halibut chumming, based on high amino acid content, are:
Mackerel: Extremely oily and nutrient-dense
Horse herring: Dense, high in protein
Sardines: Small but packed with oily flesh
Anchovies: Potent despite their size
Canned chub mackerel: Convenient, concentrated, and shelf-stable
Bonus: Fish-based cat food is a powerhouse ingredient because it often includes hydrolyzed proteins, which are already broken down into amino acids like alanine and glycine—perfect for chumming.
💡 Quick Rule of Thumb: If it’s oily, fishy, and rich in muscle tissue—it’s probably loaded with the amino acids that halibut crave.
Understanding the science helped us upgrade our fishing game in a big way. And now we build every chum mix around the biology of what halibut are designed to detect. It’s not just about stink—it’s about scent science.
How to Choose High-Amino-Acid Bait
Focus on oily, protein-packed fish:
Mackerel – oily and rich in amino acids
Horse herring – dense and high in protein
Sardines – nutrient-packed and oily
Anchovies – smaller but potent
Chub mackerel (canned) – super convenient
Add cat food for a boost: Fish-based cat food often includes hydrolyzed proteins loaded with alanine and glycine.
Why alanine and glycine matter:
Trigger feeding reflexes
Detected even in trace amounts
Found naturally in decaying bait
💡 Rule of Thumb: If it’s oily, fishy, and rich in muscle tissue—it’s probably packed with the amino acids halibut crave.
📊 Backed by Research:
We pulled together data from the Journal of Amino Acids and fisheries databases to compare the alanine and glycine content across common halibut bait types. These amino acids are potent feeding triggers for Pacific halibut, and this chart helps visualize which baits give you the most bang for your buck in scent-driven attraction.
As you can see, cat food, chub mackerel, and mackerel come out on top. This is why we use them as foundational ingredients in our chum mixes—they release a strong chemical scent trail that halibut can detect from long distances. So when you’re building your bait and chum plan, this chart helps you do it smart, not just smelly.
Sources:
Mohanty, B. P., et al. (2014). "Amino Acid Compositions of 27 Food Fishes and Their Nutritional Profile." Journal of Amino Acids. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4213980
Fitaudit.com nutritional databases for alanine/glycine profiles: https://fitaudit.com
What the NOAA Report Teaches Us (And How to Use It On the Water)
Current Speed Controls the Chum Trail:
Picture this: you're anchored in a nice current, and your scent trail is stretching behind your boat like a smoke signal underwater. According to NOAA research, even at a modest current of 0.6 cm/sec, your bait's scent can travel up to 43 meters in just two hours.
💡 The key takeaway? Faster currents spread scent farther—but also thin it out. Slower currents create a thicker, more concentrated trail—but it won’t go as far. So when you’re setting up your drift or anchor, take a second to visualize where your scent is heading. Ideally, it’s flowing right into a fishy-looking edge or drop-off.
Bait Spacing Can Strengthen the Scent Field:
If you're fishing multiple rods—or even just rigging multiple baits on a spread—keep them close. NOAA modeling showed that baits spaced just 2 meters apart created a significantly stronger combined scent plume than baits spaced 4 meters apart.
That means if you’re running gear both port and starboard, or stacking scent sources (like bait and a chum bag), keeping everything tight can help build a stronger, overlapping scent field that draws fish in quicker.
Tidal Movement Bends Your Scent Trail:
Tidal currents aren’t static—they rotate, shift, and swirl. That means your scent trail won’t always be a perfect straight line behind the boat. In rotary or shifting tides, the scent may curve, sweep, or even boomerang back toward the boat.
💡 Tip: The best time to deploy your chum is when the tide just starts moving. You’ll get maximum movement with minimum confusion. And if you’re fishing new water, pay attention to what direction the scent is going so you can adjust your anchor or drift accordingly.
The First Hour Is Prime Time:
Here’s something wild: up to 40% of a bait’s scent compounds are released in the first hour it's in the water. After that, the potency tapers off fast.
This means the first 60 minutes of your soak are your most valuable. So make them count. Use the freshest bait you have, get your scent trail moving early, and have a plan to swap out or refresh your chum at the one-hour mark. We keep backup chum blocks on board for this exact reason.
Source:
Olsen, S., & Laevastu, T. (1983). "Fish Attraction to Baits and Effects of Currents on the Distribution of Smell from Baits." NOAA Technical Report NMFS SSRF-1242. https://spo.nmfs.noaa.gov/sites/default/files/legacy-pdfs/SSRF1242.pdf
🎣 Want Our Go-To Chum Recipe?
Grab our Halibut Chum Recipe Cheat Sheet:
Proven base mix that creates a powerful scent plume
Best mesh bag setups for PNW currents
Supercharged additives to make your scent trail unmissable
👉 [Click here to download the cheat sheet]
It’s free, fast, and easy to use before your next trip.
Tight lines, friends! See you on the water.
Jamie & Scott Propst
Anglers Unlimited
Catch More Fish. Have More Fun.
