Since the mid-1980s, Meramec River watershed fisheries biologists havenoticed something interesting. It began almost imperceptibly, but has since gained plenty of strength. In some locations, it has completely changed things; in others, things remain normal. Some anglers have noticed it, too.
What is this phenomenon? Jet boats? Success of plastic lures? No, it seems many Meramec River watershed streams have become the Spot for spots. Spotted (Kentucky) bass, that is!
Spotted bass are not native to the Meramec River basin. Fisheries biologists hadn’t documented their presence until 1985 captures in the Meramec River, around Pacific, and in Big River at House Springs in 1986. Populations in the lower Meramec and Big Rivers became established by 1990 and began to move upstream, into other streams, most notably-- the Bourbeuse. Today, spotted bass occur in portions of many major Meramec River watershed streams. Some streams, like Meramec, Bourbeuse, and Big rivers have spotted bass in the lower third of their lengths.
Ok, but is this a problem?
In streams where they are native, like in southeastern and southwestern Missouri, spotted bass do well, coexist with other black bass, and provide good fishing. However, in much of the Meramec River basin, spotted bass rarely seem to reach 12", grow slowly, and may compete with native smallmouth and largemouth bass. They also hybridize with smallmouth bass and now outnumber smallmouth and largemouth in lower Big and Meramec rivers. All these things add up to trouble, if you like smallmouth and largemouth fishing in Meramec watershed streams.
Under normal statewide regulations, few Meramec watershed spotted bass grow to legal harvest size. Their growth rates are slower than smallmouth and largemouth. Also, for unknown reasons, few seem to survive past eleven inches. In addition, since they grow slower than smallmouth or largemouth, they are free to reproduce longer, prior to being available for legal harvest. Due to the 12" length limit, anglers must throw back most spotted bass they currently catch, which allows those fish to increase their numbers. At the same time, smallmouth and largemouth (due to faster growth) may be harvested, outside of existing special management areas, sooner than spots.
Do spots compete with native smallmouth and largemouth bass?
In these locations historically, smallmouth bass were the dominate black bass and spotted bass did not exist. Now, spots are king and overall numbers of smallmouth are shrinking. Some similar trends may be appearing for largemouth in the middle Meramec River. Spotted bass diet is similar to that of smallmouth bass. So, competition for food and space could be happening.
Spotted bass hybridize with Big and Meramec River smallmouth bass and have been genetically analyzed. In some cases, the hybrids are fertile, which would allow them to breed with other fertile hybrids, smallmouth, and/or spotted bass to create - who knows what. Will this continue?
What brought on this invasion of spots? Why did it change now? How far will it go? What can be done to correct the change? Good questions, unfortunately, there are not many definitive answers.
Non-native critters expand their ranges for a variety of reasons (like,accidental or purposeful stocking), but the ultimate culprit might be overall reduction in the quality and amount of smallmouth habitat. Think about Meramec River watershed streams over the last 30 years. Have you noticed any changes? More gravel, fewer deep pools and chutes? More erosion? Floodplain filling? Add impacts of urban sprawl (stormwater management, erosion, non-point pollution, etc.) and you begin to see a pattern.
Habitat loss, on a watershed basis, began when the land was settled, and timber harvested. Lack of soil erosion practices allowed the Ozarks’ thin, rocky soils to flow into small streams. This gravel is now making its way through larger streams, filling deep holes along the way. Stream side trees were the next to go, destabilizing streambanks. Some farming practices and poorly treated septic systems helped to compromise water quality. Gravel dredging destabilizes channels and ruins habitat. Most recently, dumping of stormwater and other development practices increase erosion. Has the Meramec basin incurred enough of this abuse to encourage spotted bass to invade its streams? It’s possible. Some say - probable.
Spotted bass movement could involve other habitat variables or be a simple function of building large populations in nearby watersheds that then spilled over into the Meramec. In any event, it seems clear that spotted bass populations began to grow in the lower Meramec and moved upstream from there.
In general, spotted bass seem to favor habitats that look like run down smallmouth habitat. Cut banks, slower currents, and downed trees all hold some smallmouth in the absence of spots. But, these seem to be prime spotted bass locations in Meramec streams, now. Since we are not sure why this spotted bass invasion is taking place, predicting how far it will go is impossible. But, most biologists think that stream reaches with good smallmouth habitat will continue to be dominated by smallmouth, while degraded habitats are ripe for spots.
What can be done?
The most immediate and easier fix involves relaxing protections on spotted bass. Beginning March 1, 2002, all streams that flow into the Meramec River (including Big, Bourbuese, Huzzah, Mineral Fork, and Courtois and their tributaries) will have a new spotted bass fishing regulation - no length limit and daily limit of twelve. In other words, MDC is saying, "Hey anglers, take some Meramec watershed spotted bass, PLEASE!" Perhaps, increased harvest will slow this spotted bass juggernaut and help ensure native smallmouth and largemouth remain the dominant black bass in the watershed.
When was the last time MDC asked anglers to harvest MORE fish?!? Well, here is your chance to help bass fishing and enjoy a meal of fish at the same time. For this regulation to succeed, anglers must be able to identify spotted bass and be willing to harvest small ones. Spotted bass do not look like smallmouth bass, but do resemble largemouth bass. Both are green fish and have a dark horizontal stripe on their sides. However, there are several differences largemouth and spotted bass which can be easily learned including: jaw length, rows of spots, cheek scales, and tongue patch.
A largemouth’s jaw extends well past the back of their eye, unlike the spotted bass’ jaw which only extends to the back of the eye. Spotted bass have rows of disconnected spots along their sides, under the dark horizontal stripe. Largemouth do not. Scales behind the eyes of largemouth bass are nearly as large as those behind the gill openings. On spots, the scales are much smaller than the ones behind the gills. Finally, all spotted bass have a small, rough tongue patch (like sandpaper). If no tongue patch exists, it is a largemouth bass. Using all these characters will ensure good identification. But, if you are unsure, you can just release the fish.
The larger, more permanent fix involves improving the habitat. That can be most appropriately handled by putting together a watershed plan to address the concerns listed previously. Throwing in a few boulders or other habitat improvement structures won’t get it done. This planning process would need to involve everyone: anglers, floaters, developers, farmers, municipalities, agencies, etc.. The plan would identify the watershed’s problems and devise solutions. Obviously, that’s a much larger effort.
Spotted bass have made their move into the Meramec watershed. And they seem to have a pretty good foothold; making the Meramec and its tributaries the Spot for spots. However, anglers will be given the opportunity to help slow or reverse this trend. All anglers need to do is: learn how to identify spotted bass and warm the grease in the fry pan.
