I often wonder if smallmouth are afforded the angling protections they deserve. Smallmouth, unlike trout, stripers and a few other game fish in Missouri, are native.
I believe they undoubtedly symbolize the health of an Ozark stream. They are a remarkable species and a brute when it comes to tangling with one at the end of a line.
And now we have arrived at that time of year when they are hard at work, propagating their species. The smallmouth spawn has begun.
Affording smallmouth greater protections, especially during the spawn, is my subjective and biased opinion.
So first let me lay out the objective and quantifiable facts regarding the smallmouth spawn and effect angling pressure has during the spawn. Then maybe after taking a look, you’ll consider the smallmouth spawn a time to target trout and give smallmouth their privacy.
This spring water temperatures will warm to around 60 degrees and the spawn will begin. However, not all smallies in a given water body will not spawn simultaneously. Usually, the largest and oldest smallmouth spawn first. The spawning season is physically exhausting for them and takes weeks.
Therefore, in preparation, smallmouth feed heavily and aggressively during the pre-spawn period to fatten up and store as much energy as possible. When spawning temperatures arise, they transition out of feeding mode and make their way to the shallows to begin nest building.
The male selects a nesting site that is somewhat sheltered or protected from strong water currents. In an Ozark stream this will usually be at a depth of less than a meter. The nest might be within an undercut bank, root wad or just seemingly exposed.
The male more or less uses his tailfin like a broom, sweeping out a nest by brushing his caudal fin back and forth, and clearing any large substrate with his mouth. A concave bed will emerge with a diameter of about 2-3 feet. The process of nest building and maintenance can take anywhere from a few hours to two days to complete.
The male now anxiously awaits the arrival of a female. She will select a bed and deposit her eggs in the nest while the male then emits sperm. As many as 10,000 eggs can be deposited and potentially fertilized. After the female has deposited her eggs her role in the spawn is essentially over.
The male’s role has really only begun. For a brief period of time, these embryos are susceptible to abrupt fluctuations in water temperature, smothering from excess siltation (brought on by increased stream flow) and infection; there is little the male can do about these things.
He is active in fending off any opportunistic predators that might be looking to consume embryos, and later young fry, from his nest. There are several species of fish that would love to make a meal of young smallmouth fry.
The male guards his progeny only so long as necessary. But this can last between a couple weeks and a month. Eventually, the young fry disperse and abandon the relatively safe and familiar confines of shallow water structure, his job is done.
All of this occurs in a window of time that unfortunately sees a marked increase in angling pressure in the Ozarks. Active smallmouth nests can be observed from April 15 through June 15 in most Ozark streams.
Like me, this is a time when many of us are thinking about spending more time on the water. This increased activity might negatively impact the smallmouth spawn.
A large number of studies have been conducted to determine if angling pressure during this sensitive time period adversely affects the success of the smallmouth spawn. The overwhelming answer is yes, it does. There are several reasons for this and I will highlight just a few.
The first reason is the negative impact of harvesting smallmouth (even legally), especially males during this time period. If the male is not present to guard the nest the offspring essentially have zero chance of survival. The fry will be consumed by predators. But what about catch and release?
Well, research tells us that even this noble endeavor has significant negative consequences during the spawn. Two things are going to result if you catch a male that is actively nest guarding young.
Research has shown that even if you minimally play and handle the fish and return it to the water in a very brief period of time, that male will not nest guard as well. Males angled from a nest may come back to the nest but do not guard as actively as a male that was not removed from a nest.
Simply put, angled males are less defensive and the nest is more susceptible to predation.
However, let’s assume you played the fish for a bit too long and you took a few photos. If the time from hooked fish to time of released fish is greater than five minutes there is a 70 percent chance that the male will completely abandon his young. Same as if you had put him in the live well.
There is always a physiological cost to catch and release and it is most dangerous during the spawn. And this is only the direct effect on the father, not the young.
While you were catching the fish and releasing him, nearby bluegill were presented with a buffet of smallmouth fry in the unprotected nest. If this goes on for too long the male will eventually abandon his nest when there are not enough fry to be worth his time and effort. Sad but true.
So, timing is everything. Avoiding catching actively spawning smallmouth is of course the best approach if we want a healthier and sustainable smallmouth population. But I’ve heard several anglers tell me they wait until late May or even June to fish for smallies.
This may not always be enough. Through these studies and many others it has been shown that a male smallmouth will be more aggressive the older his offspring are. So at week four during nest guarding, a male is harder at work protecting his young than at week one.
For example, if a nest is fertilized in early May, than for some males, the most important stage in nest protection might be in June.
The evidence is clear, despite our good intentions, or how careful and how light we tread, catching smallmouth during the spawn (even late) is deleterious for the species. So what can be done and what should be done?
Well, we already have restrictions on harvesting smallmouth during most of the potential spawning times. But what might be necessary is the creation of no fishing zones or no fishing time periods.
Maybe we can identify important spawning habitat and close it down on some of the more well-known smallmouth streams during the spawn. Also, we could identify just a couple of weeks that are most critical to smallmouth survivorship and require all anglers to avoid smallmouth.
I know logistically and politically this might be next to impossible but it also might be what’s necessary to drastically improve smallmouth populations in certain streams.
In the meantime if we fish during the spawn, let’s fish responsibly. I think we can still get out and fish and have a successful spawn. To do this you need to understand the habitat in your stream.
Remember spawning fish will be shallow. Now would be the time to target those deeper pools where the females have retreated back to, post spawn.
It may not be easy, but maybe there are a few looking to get back to feeding after expending that energy during the spawn. Catching the girls later in the spawn should be fine since the males are now on their own.
And if nothing else, pinch the barbs and return any fish as quickly as possible to the water.
Remember, his nest is unguarded and he doesn’t have any time to pose for pictures.
By Ryan Combs