Every spring, as the water warms and bass move shallow, the same question bubbles up in fishing circles: Should we fish for smallmouth bass during the spawn? It’s a loaded topic—part science, part ethics, and part personal experience.

I’ve spent plenty of time fishing during the spawn without thinking twice about it. But in recent years, I’ve started paying closer attention to what’s actually happening below the surface—and what role we play as anglers in that process.

This post breaks down what the spawn really means for smallmouth bass, how to recognize it, and why some anglers (myself included) are rethinking how we approach this time of year.

Whether you’re new to fly fishing or have years on the water, my hope is that this gives you a clearer picture—and helps you make your own call about fishing the spawn.

What Does Spawn Mean for Bass Fishing?

Spawning is the time of year when smallmouth bass focus on one thing: making babies. 

For anglers, the spawn is one of the most polarizing times to fish. Scientifically, the spawn refers to the reproductive phase when mature bass create nests (often called “beds”) and lay or fertilize eggs. It’s a highly energy-demanding period, and both males and females change their behavior dramatically. 

Females usually lay eggs and leave shortly after, while males guard the nest fiercely for up to two weeks, protecting eggs and fry from predators.

This behavior makes them vulnerable to anglers. They’re not feeding out of hunger—they’re reacting out of aggression. That means even a poorly presented fly or lure can get a defensive strike. And while this can lead to some memorable catches, it raises big questions about long-term population health, especially if too many nesting males are pulled from their beds.

I have noticed that during the spawn, fish can either have lockjaw-only focused on protecting their fry- or attack anything that comes within striking distance of their beds. It depends on the fish, but there is often little in-between. At times, fish may nudge your fly with their nose or whack it with their tail to get it away from their bed, but more often than not they’ll attack your fly out of their protective instincts. 

How Can You Tell If Fish are Spawning?

Spotting spawning smallmouth is all about observation. These fish behave very differently when they’re on beds, and with a little practice, it’s easy to tell what’s going on beneath the surface.

First off, look for shallow, clear water—typically 1 to 5 feet deep with a firm bottom like gravel, sand, or small chunk rock. Spawning bass clean out round or oval “beds” on the bottom that are lighter in color than the surrounding substrate. These beds can range from the size of a dinner plate to a pizza, and you’ll often see a single fish hovering just above the center.

The most obvious sign is that “locked in” posture. Males—who guard the nests—will stay tight to the bed and will circle or dart quickly back if they get pushed off. They often won’t leave the area unless really pressured, and even then, they usually return quickly. These fish aren’t patrolling or cruising. They’re holding position and reacting to anything that comes close. That’s your giveaway.

Another cue? Aggression. If you’re sight fishing and a smallie bolts in to nose or nip at your fly the second it lands—without following or evaluating—it’s likely protecting a nest.

If you’re seeing multiple fish in shallow water but no beds, it might be pre-spawn staging. But once they start pairing up and sticking to tight zones, it’s likely the spawn is on.

When I’m out fishing, the most obvious signs of spawning fish are single smallies on top of cleared out beds. The beds are easy to notice once you know what you’re looking for and if there’s a fish on top of it, he’s in full-on protection mode. 

Also, you may see an empty bed at first, but look again later and there is a fish guarding it. In the waters I fish, I’ve noticed that if and when fish leave their beds to shoo off predators or debris, they quickly return. It’s actually kind of fascinating to watch. These fish are locked in with only one thing on their mind- protect their young.

What Water Temperature Do Smallmouth Spawn In?

Smallmouth bass typically begin spawning when water temperatures hit the low to mid 60s. In general, 60 degrees is a good marker for spawning conditions. That sweet spot is usually after a stretch of consistent warming in the spring, once the risk of cold snaps has passed. In many regions, this lines up with late April to early June, depending on latitude and local weather patterns. I’ve had years where I’ve seen spawning fish in mid-April, others not until mid-May, it all depends on the conditions. 

Where Do Smallmouth Like to Spawn?

Smallmouth bass are pretty picky when it comes to where they spawn. They like clean, shallow water with firm bottoms—think gravel, sand, or small cobble. Mud and silt are generally avoided because they can smother the eggs and reduce oxygen flow. In rivers, look for slow-moving pockets just off the current—like behind boulders, along inside bends, or in eddies near riffles.

In the waters I fish, I notice most of the beds are tucked near the shore in slower moving water. They seem to prefer spots protected by structure as well. Trees, rocks, sunken bushes all provide some extra cover from predators. 

Depth-wise, most spawning beds are in 1–5 feet of water, but smallmouth will go deeper in big waters. The key is sunlight penetration. They want just enough light and warmth to support egg development but still be shallow enough for the male to effectively defend the nest from predators.

I’ve also noticed that smallies will return to similar spots every year. There seem to be some prime locations for spawning and once the water temperatures hit that 60 degree mark, I can almost guarantee there are fish in these fishing spots. If you fish the same waters year after year, I would bet you start to notice the same! 

Should You Fish During the Spawn?

This is the big one—and there’s no one-size-fits-all answer. Like nearly everything in fishing, the answer is “it depends.”

Scientifically, yes, fishing during the spawn can negatively impact smallmouth populations, especially if males are removed from their nests. Studies reinforce that even short-term removal of smallies can reduce spawning success. Another study had similar findings.

And ethically, it’s a gray area. It depends on how you fish, how often you fish during the spawn, and what kind of water you’re fishing.

From a biological standpoint, the concern is clear: when you catch a nesting male, even for just a minute, you leave the eggs or fry unprotected. Studies have shown that bluegill, perch, and other nest raiders can swoop in and wipe out a nest in under two minutes. That’s a full year of reproduction lost. And if you’re on a small body of water, or one with limited spawning habitat, it doesn’t take much pressure to have a noticeable impact.

Some other scientific studies also point out that good catch-and-release practices significantly mitigate the chances of fry predation. Getting a fish back into the water close to its bed as quickly greatly reduces the odds their offspring will be lost. 

Catch-and-release helps—but it’s not a cure-all. If the goal is to protect the population, minimizing disruption to spawning behavior is key. But if you’re fishing a large, healthy system with lots of spawning habitat, the impact might be smaller. However, if you’re on a small body of water with limited access to resources, you may be putting the system at risk by fishing for spawning fish. 

Personal Thoughts on Fishing the Spawn

For a long time, I fished the spawn without giving it much thought. If a fish was shallow and locked in, I cast to it. If it ate, I celebrated the catch like I would any other. It wasn’t until recently that I started thinking more seriously about the impact it might have—on individual fish and on the fishery as a whole.

Last spring on the DuPage River in Illinois, I was sight-fishing in clear water and saw a big male holding tight to a nest. I made a bunch of casts right on top of him, trying to get him to bite and after a while I finally hooked him. 

After releasing the fish, I watched as he took his time returning to the bed, back to guarding his nest. Something about that moment didn’t sit right. For the first time, I felt guilty. Not because I caught the fish, but because I probably disrupted something bigger than me.

At the end of the day, I get that people just want to catch fish. I’m not here to tell anyone how to enjoy their time on the water. But if you do spot a fish on a bed, especially one that’s clearly spawning, maybe let it be. There are plenty of other fish in the water. Give that one a pass, and let nature take its course.

Pros and Cons of Fishing the Spawn

Fishing during the smallmouth spawn is a bit of a double-edged sword. There’s no denying how exciting and productive it can be—but there are tradeoffs worth thinking through.

Pros

• Visual Fishing: Sight-fishing to aggressive bass guarding beds is some of the most engaging freshwater action out there. You see the fish. You read its behavior. You present the fly just right and watch it react.
  
• Learning Opportunity: For newer anglers, it’s a great time to observe fish behavior—like how smallmouth react to pressure, how they hold on beds, and how different presentations trigger strikes.
  
• High Catch Rates: During peak spawn, bass are locked into shallow zones and more likely to strike out of defense. For folks looking to build confidence, it’s hard to beat.
  

Cons

• Potential Nest Disruption: As we’ve covered, removing a male from a nest even briefly can lead to total egg loss—especially in high-predator systems.
  
• Long-Term Impact: On small or heavily pressured waters, repeated fishing during the spawn can affect recruitment year to year.
  
• Ethical Gray Area: Not every angler feels right targeting spawning fish, even with barbless hooks and careful releases. Some see it as disrupting a natural and essential process.
  

So… what’s the responsible move?

That depends on the system, the pressure it sees, and how you personally approach catch-and-release. In large, healthy rivers or lakes, the risk might be small. But on more fragile fisheries, a little restraint—like skipping beds or spreading out pressure—can make a big difference.

Conclusion

Fishing during the smallmouth bass spawn brings with it both opportunity and responsibility. It’s a time when fish are visible, aggressive, and often easier to catch—but also at their most vulnerable. The science is clear: disrupting nesting behavior can affect reproduction. But it’s also clear that thoughtful, low-impact angling—especially in healthy systems—doesn’t have to come at the fishery’s expense.

At the end of the day, it comes down to awareness. Whether you choose to fish during the spawn or not, understanding what’s happening beneath the surface helps you make more informed, respectful decisions. Sometimes that means backing off a bed. Sometimes it means switching spots or simply being more mindful of where you step.

Personally, I would not encourage fishing for spawning fish. There’s a non-zero chance of negatively impacting the fishery for future generations. There are plenty of other fish to catch and other times to target these smallies. Let them do their thing!