muddy water ramblings....

Since the rivers are all a mess it seems like as good a time as any to do a little studying. Forgive the disjointed and hop scotch writing, Its more a collection of things I find interesting than a polished piece of writing...

In Japan the smallmouth bass has been described as the “world’s most disastrous invasive species” . Numerous methods to remove them have been considered, as their introduction is a major concern for the conservation of native biodiversity. Invasive bass constitute a “serious biohazard,” and several studies on biodiversity in Japan promote their eradication in Japan. Numerous studies have found that in lakes and streams anywhere smallmouth bass have been introduced they completely change the dynamics of baitfish populations within a few years.

A study done by the University of Wisconsin found that bass greatly prefer crayfish with smaller claws. And that crayfish with large claws were approached with much greater caution and often involved the bass circling the crayfish at length for some time trying to attack it from behind. And it was found that if the crayfish acted aggressively with the claws up defensive posture that we have all been trained to look for in out plastic imitations, the bass quite often just swam off and looked elsewhere for an easier meal. There are about a billion youtube videos out there of guys throwing crayfish into aquariums with bass. What does the bass do? He sucks it in, blows it out, then repeats as often as necessary till he either kills it or renders it helpless enough to eat. Three studies, one done on the New River in W VA and one done in central Ohio and one done on the Current and Jack's Fork in Missouri found that smallmouth bass targeted crayfish in the one to two inch range and the one done in Ohio found they preferred a crayfish that was 1 1/4 inches long over one that 1 1/2 inches long! And bigger smallmouth seem to be even more selective than smaller bass. In fact one study done in the Ozarks found that big smallmouth were even more likely to take a crayfish UNDER 1 1/4 inches long than other sized bass!

According to the study, Associations of turbidity and diet in smallmouth and spotted bass and creek chubs of the Scioto River, "it is possible that there may have been a switch to crayfish at high turbidity levels." But the same study quickly states that this is not conclusive but it is food for thought.

One study done on the Current River in Missouri I found very interesting. They first seined and measured the baitfish in the river The average size minnow in the river was between an inch and an inch anda half long. But the average size minnow eaten by smallmouth was three and a half inches long. It was felt that smallmouth preferred larger baitfish but didn't pass up an of the smaller ones they could catch.

And there is a study that was done on the Columbia River that I find really fascinating, especially for anyone interested in targeting larger smallmouth bass. In this study it was determined that for smallmouth less than 250 mm long crayfish were far and away the most important food item. But smallmouth in the 250 to 300 mm range ate more sculpin (up to half of their diet) than any other food item and that smallmouth over 300 mm ate more suckers (52%) than any other food item.

So what can we conclude from all that? To me it means a couple things. There is a reason that tubes and rebel craws are standard smallmouth bass lures, they imitate small crayfish that smallmouth bass love. Don't use that big plastic texas rigged craw with the huge claws on it. I don't care if you caught a five pounder on it twelve years ago. If I fished a piece of an old sock on a jighead long enough I might catch a monster, that doesn't mean it's the best thing to use. If you do use one of those big plastic craws you just might be selecting for smaller smallmouth bass as well since the bigger bass are the ones most likely to eat a craw smaller than 1 1/4 inches long. And I feel these validate something I've felt in my gut after 40 years of river fishing, that grubs and swimbaits will catch you bigger smallmouth year in and year out in rivers than tubes will. And on the whole I think river fishermen use crayfish baits that are way too big and minnow baits that are way too small. If you are trying to catch a big one that is.

And here are a couple things I gleaned from the amazing book Lunker! by Bob Underwood. Bob was an accomplished diver, photographer and avid fisherman. He conducted tons of experiments on bass and observed the results both by diving and thru the use of large aquariums. Some things I found interesting...
Bass caught out of a school that were released unharmed quickly rejoined the school. Those bass were sometimes re-caught. But bass that were injured and were bleeding were not accepted back into the school and the entire school would swim away to avoid them. As long as bass were released unharmed the bass would often continue to bite. But if a bass was injured to the point that it's skin was broken the entire school would shut down and not bite. Oddly enough something like a puncture wound inside the mouth didn't affect the fishing unless the fish was injured to the point of bleeding.  He felt injured bass released some kind of scent that alerted other bass of danger. He then conducted experiments of baitfish and found that the same thing held true for other fish species as well. Maybe it isn't so much a case of replacing a bait with a livelier one as it is replacing it with one giving off a new and stronger "danger" scent. He also removed a tiny bit of skin off of the back of a bass and hooked it on the treble of a plug. That scared the heck out of bass and they avoided the lure drastically.

According to the In-Fisherman book Smallmouth Bass most of the time unless the fish is extremely thin or full of eggs you can get a really close estimate of the fishes weight by multiplying length x length x length and then dividing by 1600. For example 18 x 18 x 18 = 5832. 5832 divided by 1600 = 3.6 pounds or 3 lbs ten ounces. which makes your average 20 incher right at five pounds. No idea if it works for largemouth but i'd think it would be slightly different.

Smallmouth bass have been introduced to Africa, Europe and Russia, as well as both east and west across Canada. The initial expansion of smallmouth bass range took place in the mid-1800s, to central New York State through the Erie Canal, then across the United States as far as California. They were introduced into California in 1874  and transplanted into the New England states in the late 1800s. Smallmouth bass are now found in all states except Florida, Louisiana and Alaska.

High water and smallmouth bass....
During wintertime flooding one study found that smaller smallmouth bass were often killed but that wintertime flooding did not seem to affect the population of larger smallmouth bass. And another study found that early springtie flooding before the spawn actually seemed to improve that years success in spawning. (possibly by washing away silt?) But of course major flooding right in the middle of the spawn was a disaster.

Up to 20 percent of adult smallmouth bass do not spawn during any given year. It was found in one study that these fish do not begin develop eggs and that whether or not they will spawn seems to be predetermined sometime the year before though scientists are not sure how this process takes place. For me that means I just go on fishing like I always do and avoid the moral dilemma of chasing spawning bass. During any given year up to 40% of all smallmouth bass nests fail but a successful nest may ultimately produce about 2,000 fry.  Some bass repeatedly home to the same nesting site each year, and over 85% of these return to within 130 meters of where they nested in previous years.

Usain Bolt in a race ran nearly 28 miles per hour which is twice as fast as a smallmouth can swim. Smallmouth bass are not built for speed but instead for quick acceleration.

A 2001 survey by TWRA biologists reported the lengths of the smallmouth bass populations in Tennessee streams. Many of the populations surveyed had a low abundance of quality-size bass. The average proportional stock density was 34, meaning that only 34 percent of the stock length fish (over 7 inches) in the population were over 11 inches long. they also reported in 2001 on Dale Hollow there was an estimated 106,228 smallmouth caught and 12,227 kept.

 In streams, smallmouth bass can live to be 15 years of age, and attain a maximum length of about 21 to 22 inches. The average stream smallmouth bass grows to 14 inches in length by age 6

And yeah we all know the world record smallie weighed eleven pounds fifteen ounces but the most amazing part to me is that the fish was twenty seven inches long. Imagine a twenty seven inch smallmouth.