Unnatural Selection causing fish to get smaller

[MoCarp]

1 hour ago, tjm said:

Did anyone keep records of the prey species available to stream predators in the 19th or 20th centuries, when the fish reportedly grew so large? 

My mind tells me that there were lots more crawdads in the Elk River tributaries in the '50s than there are now, I believe there were lots more crawdads in the '80s than there are now. Where as a small boy I caught scads of crawdads and even my kids caught some, I don't recall seeing any in several years. I'm sure there are still some there, but so few that they aren't usually seen. 

 

 

I noticed that the crawfish population in the elk river drainages are not as good as when I was younger...try catching some for bait

you don't see the slab rocks that were in the creeks, people hauled them out for land escaping etc or gravels silted over the areas...perhaps prime crawfish habitat has degraded over the years...old timers always said the old holes have been filling in...sad to say not many old river rats still around that knew the drainage from way back

[Guest]

 

Deleted.

 

[fishinwrench]

2 hours ago, siusaluki said:

 

 

That is typical behavior for bass in any lake that has gizzard shad, threadfin shad, alewives, or any other schooling preyfish.....Just because you've been fishing the banks your whole life doesn't mean they weren't out there before.

I realize that, but shad are everywhere.  There's no need to suspend out over bare structureless deep water just to feed on shad.  The shallow flats are full of forage, shad of all sizes included.  Matter of fact it is easier for LM bass to get a belly full of shad there than it is out in the middle of the lake.

[tjm]

6 hours ago, MoCarp said:

I noticed that the crawfish population in the elk river drainages are not as good as when I was younger...try catching some for bait

you don't see the slab rocks that were in the creeks, people hauled them out for land escaping etc or gravels silted over the areas...perhaps prime crawfish habitat has degraded over the years...old timers always said the old holes have been filling in...sad to say not many old river rats still around that knew the drainage from way back

I believe  the crawdad loss is for reasons other than rocks and gravel, saw some odd looking crayfish in the '90s for a few years and then near none since. I suspect exotics took over then eventually died out, no proof. Think Indian Creek still holds good numbers of crawdads, it did a  few years ago.  It doesn't flow from Ar or a golf course either and that may make a difference.

My point was, is there evidence that those streams can support a great number of larger fish? Won't the predators outnumber the prey at some point?

I have fished, waded, swam in the two sugar creeks since the mid '50s and I see probably ten times fewer fishermen on the whole drainage than there were back when. More floaters on the Elk/Cowskin, but really few fishers and they mostly go back where they came from after the weekend, imo, any loss of fish quality/size / quantity is unrelated to the consumption. I grew up with stories of seining those streams with hog wire and two teams of horses, hauling a wagon load of fish at a time; the old ones didn't fish for sport.

Heard anecdotes of hand catching cats over fifty pounds out of those creeks too. It may be our modern methods keep us from seeing the real big fish or that mans desire for green grass is killing the streams' historic character. 

[MoCarp]

2 hours ago, siusaluki said:

 

 

That is typical behavior for bass in any lake that has gizzard shad, threadfin shad, alewives, or any other schooling preyfish.....Just because you've been fishing the banks your whole life doesn't mean they weren't out there before.

perhaps more shore oriented prey are less available than before?

15 minutes ago, fishinwrench said:

I realize that, but shad are everywhere.  There's no need to suspend out over bare structureless deep water just to feed on shad.  The shallow flats are full of forage, shad of all sizes included.  Matter of fact it is easier for LM bass to get a belly full of shad there than it is out in the middle of the lake.

perhaps shad are not so nutritious as say bluegills /greensunfish/crayfish/ or heaven forbid baby buffalo or baby carp?

3 minutes ago, tjm said:

I believe  the crawdad loss is for reasons other than rocks and gravel, saw some odd looking crayfish in the '90s for a few years and then near none since. I suspect exotics took over then eventually died out, no proof. Think Indian Creek still holds good numbers of crawdads, it did a  few years ago.  It doesn't flow from Ar or a golf course either and that may make a difference.

My point was, is there evidence that those streams can support a great number of larger fish? Won't the predators outnumber the prey at some point?

I have fished, waded, swam in the two sugar creeks since the mid '50s and I see probably ten times fewer fishermen on the whole drainage than there were back when. More floaters on the Elk/Cowskin, but really few fishers and they mostly go back where they came from after the weekend, imo, any loss of fish quality/size / quantity is unrelated to the consumption. I grew up with stories of seining those streams with hog wire and two teams of horses, hauling a wagon load of fish at a time; the old ones didn't fish for sport.

Heard anecdotes of hand catching cats over fifty pounds out of those creeks too. It may be our modern methods keep us from seeing the real big fish or that mans desire for green grass is killing the streams' historic character. 

I know that the influx of the "newly american" harvesting fish in the drainage or perhaps crawfish too? rusty craws are a problem yet they run off from all the golf courses in Arkansas can't be good for the little lobsters...yet again more studies are needed

[tjm]

Not enough access for new Americans to do any harm, city parks and the few MDC access points don't have much effect on the streams as whole, mostly they only benefit the folks wealthy enough to go boating. No public access on Little Sugar. But golf grass isn't the only source of nutrient, there is a zillion acres of fescue that was not here at all before 1970.

In your search for bait did you see many madtoms or sculpin? I don't do as much as I once did but my limited searches show them scarce also.

[Haris122]

 I think nowadays in ocean fisheries that seems to be the big trend, since the fish that grow fast but mature slow, tend to get caught as they reach or exceed the minimum size before they can pass their genes on enough. So the genetics of cod for example, end up trending towards fish that grow slower and reach maturity faster. That way they reproduce more often before they reach the minimum size to be kept. If that similarly affects fish around here though is a different story.

[MOPanfisher]

There are many things that affect habitat, from removal of the riparian vegetation and farming right up to the channel edge, to heavy reliance on fertilizers and pesticides. I know a couple places on a local creeks I used to fish as a kid, that dad would point to and say we used to dive off that big Rock, this was the swimming hole.  At that time it was only about 3 feet deep, but it used to be over your head, that is happening  in many places.  Frogs and crayfish are often referred to as indicator species, they are very succeptible to things like pesticides and chemistry changes in the water.  Frogs used to be everywherewhen I was a kid, now it's difficult to find enough to be worth the trouble.

[MoCarp]

On 10/12/2017 at 10:41 AM, tjm said:

Not enough access for new Americans to do any harm, city parks and the few MDC access points don't have much effect on the streams as whole, mostly they only benefit the folks wealthy enough to go boating. No public access on Little Sugar. But golf grass isn't the only source of nutrient, there is a zillion acres of fescue that was not here at all before 1970.

In your search for bait did you see many madtoms or sculpin? I don't do as much as I once did but my limited searches show them scarce also.

I don't see as many madtoms, in fact can't remember the last time I saw one, guys used to rig a metal net on a long pole to dip them out of the gravel on the elk river drainage...a bit of micro fishing at night might be in order.....used to be a bunch to sculpins in RR...since the holes are less deep.....unsure of them ether they might frown on a long handled net ar the park....

27 minutes ago, MOPanfisher said:

There are many things that affect habitat, from removal of the riparian vegetation and farming right up to the channel edge, to heavy reliance on fertilizers and pesticides. I know a couple places on a local creeks I used to fish as a kid, that dad would point to and say we used to dive off that big Rock, this was the swimming hole.  At that time it was only about 3 feet deep, but it used to be over your head, that is happening  in many places.  Frogs and crayfish are often referred to as indicator species, they are very succeptible to things like pesticides and chemistry changes in the water.  Frogs used to be everywherewhen I was a kid, now it's difficult to find enough to be worth the trouble.

chytrid fungus has devastated amphibians world wide, crawfish have been less diverse, I know some of the same creeks in Jasper co. have less depth than before, old timers tell me the same thing, so its been going on a while, I know of a spring on a creek crossed by I44 that was buried during road /bridge work and that section is VERY different since..personally I feel they should restore the creeks by the bridges, even if it means dredging out the influx of gravel 12 months later...their attempts to keep soil and gravels from washing in is a joke...no oversight on this at all

[tjm]

I'm not sure that the gravel infill either helps or harms over the long term, it has been happening a long long time, that's part of the karst geology as I understand it; most of the gravel is sucked into the streams from hilltop sink holes, isn't it? There are sink holes where there were none fifty years ago and more numerous holes where they were back when, do the hundreds of earth tremors that we experience each year have something to do with this?  I own about a quarter mile of limestone bluff and the leaching of minerals/formation of stalactites etc. is visually obvious over time, how does this chemically affect the streams? 

When I look at a creek and see no mounds of mussel shells, no hellgrammites , no numbers of crayfish I don't expect to see numbers of large fish and I don't believe catch and release will improve the food base. I suspect that over a long period the catch and release and the size limits won't make a real difference. 

During the last sixty, or perhaps the last thirty, years (or maybe this is a thousand year trend) there has been some change in the water chemistry that is harming the life forms? Frogs, there are more in my yard and field than on the creek and I've not heard a bull frog in decades. So is it unnatural that selection that predators are adapting to a less bountiful prey base?