Why Everything You Know About Bluegill Management is Wrong---INTERESTING ARTICLE BRINGS UP MANY GOOD POINTS

[Slip Sinker]

Why Everything You Know About Bluegill Management is Wrong

BY MATT MILLER

OCTOBER 15, 2015

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Bluegills are prone to overpopulation. This is accepted knowledge among many anglers.

If you don’t catch and keep a lot of bluegills out of a pond, you’ll often hear a fisherman say, the bluegills will overrun the place. You’ll soon have a pond full of runty, stunted fish.

This is why the bag limits for bluegills are typically very liberal – it is not unusual to be able to keep 25 fish a day. It’s the angler’s duty to catch and eat as many as possible – keep the herd in check, if you will.

It sounds good, but current research suggests it’s wrong.

In fact, research conducted by Andrew Rypel, research biologist with the Wisconsin Department of Natural Resources, suggests the opposite: that liberal harvest limits on bluegills actually decreases the size of fish.

“Fish Here Aren’t As Big As They Used to Be”

Bluegills are often the first fish many anglers encounter (including me). They are common in farm and urban ponds. They’re the fish kids catch with a Mickey Mouse rod, a bobber and worms.

In the spring, many anglers target them on their spawning beds, where the biggest males are often easy to catch (see yesterday’s blog for the full details on this spectacle).

Bluegills are also popular because they’re tasty. Anglers call them and similar-sized species – crappies, perch, other sunfish – panfish. They’re the perfect size to fit in a frying pan.

Rypel and his colleagues in Wisconsin noticed something over the years: Anglers reported decreasing size of bluegills and other panfish. Of course, conventional angling wisdom would suggest the solution to this would be to harvest even more bluegills. After all, decreasing size is a sign of overpopulation.

Research tells a different story.

Rypel analyzed size trends going back to the 1940’s, and found that bluegills (and other panfish species) steadily declined in size over a 70-year period.

Researcher Andre Rypel (right)  first encountered bluegills as many of us do: as a young kid, fishing.

“The regulations are relatively liberal,” he says. “I thought one possibility might be that we were fishing them too hard. As we looked at the data, we found that evidence of bluegills becoming stunted because they were overpopulated was not as common as previously thought.”

Fishing pressure, particularly on spawning beds where bluegills are most vulnerable, can be intense. And that pressure may be decreasing the size of fish.

In response to the trend, the Wisconsin DNR reduced the bag limit to 10 fish on 10 lakes as a test. Researchers, including Rypel, analyzed fish size before and after the regulation.

They found that fish size increased on average a half-inch on maximum size and .8 inch on mean size.

That may not sound like much, but consider that a typical bluegill is six or seven inches, and a really large one is ten inches.

Rypel published the findings in the North American Journal of Fisheries Management.

A New Experiment in Bluegill Management

The next phase of the project is to implement new management strategies on 100 Wisconsin lakes. One third will have a reduced limit of 10, one third will have a reduced limit of 5, and one third will have a reduced bag limit only during the spawning season.

The management regimes will run for ten years. “We’re going to find out what different regulations can do for panfish size,” says Rypel.

The good news is that bluegill size rebounds when fishing pressure decreases. A study by Rypel in collaboration with researchers at the University of Wisconsin-Milwaukee, School of Freshwater Sciences found that the reduction in size was not likely due to a shift in genetics, as has been shown to be the case in some other prominent studies on fishing pressure.

Anglers have, in general, been reluctant to embrace size limit reductions. Rypel points out that the limit reductions may actually result in more meat harvested. That may seem counterintuitive, but it’s true. “As bluegills get bigger in length, they get exponentially bigger in weight,” he says. “So if you catch a few larger bluegills, you often get more meat than if you caught a bunch of smaller ones.”

There is still a lot biologists don’t know about bluegills. New research will likely call for more changes in fishing regulation, but Rypel acknowledges that science is only one part of fisheries regulation.

“Regulations are a blunt instrument,” he says. “They cannot account for all aspects of fisheries management. If they get too complicated, they become much more difficult to enforce. We want regulations that are easy to understand and easy to enforce. There are trade-offs. In this case, reducing the bag limit could help the resource tremendously while still meeting the expectations of anglers.”

And while the bluegill may seem an unlikely symbol for global fisheries management, what Rypel says applies to large commercial fisheries as surely as it does the local farm pond. Regulations are only ever partly about science, and they can never fully account for the complexity of a fishery.

The key for resource managers is to use sound science to create regulations that work best – for fish and for people.

“Bluegills have the opportunity to get bigger with a relatively minor shift in fishing regulations,” says Rypel. “Our research is providing the evidence that it benefits anglers, too. The findings seem counter-intuitive to many anglers, who have long believed that smaller bluegills was a sign of overpopulation. But perhaps our long-term studies can convince them that lower bag limits can mean better fishing, and bigger panfish fillets for the fish fry.”

TAGS: Field Notes, Fish, Fisheries, Nature + People, NaturePop, Weird Nature

 

Matt Miller is director of science communications for The Nature Conservancy and editor of the Cool Green Science blog. A lifelong naturalist and outdoor enthusiast, he has covered stories on science and nature around the globe. Matt has worked for the Conservancy for the past 14 years, previously serving as director of communications for the Idaho program. More from Matt

[DAVID L EITUTIS]

Free range trophy ? THAT MUST BE THE OPPOSITE OF Richmond Mill ?!

[Tony Livingston]

I'll bite.

1) There  are no guarantees of catching trophy fish, even when the variables you mention are controlled in the fashion you mentioned, LOFR. It doesn't work that way. If it did, we would see trophy bluegills coming out of the many thousands of farm ponds scattered across the country.

2) Absolutely correct that there is no one management style that will apply to every BOW. However, releasing the largest size class males may yield positive dividends, and will not hurt a thing.

3) Let's take the tree example one step further. You raise trees, and by your reckoning the mature trees are closer to the end of their life cycle, and should be harvested. Makes sense to me also. But let's add a wrinkle...let's say you have a couple trees that are exceptional, a step above your other, mature trees. And through the years, you've noticed that the nuts from those particular trees are producing saplings that show all the signs of becoming exceptional trees in their own right., Now, do you cut those parental trees down for their lumber, or do you allow them to continue to produce exceptional saplings, for an even better future harvest? That's why bluegills are not trees.....you can get a perfectly serviceable 2 x 4 from a less than exceptional tree, the same as you can carve an acceptable filet from a smaller bluegill. But when you catch that exceptional male bluegill, can you tell what it's prodigy are capable of? That's why it's better to err on the side of conservancy.

4) Free range. Back to the trees and the lumber. Let's compare my local box store lumberyard to a public BOW.  The lumber is the bluegill, and the  lumberyard is public water. I need a 2 x 4, so I head to town and pick one up. And yes, I have to find the right stack, and sort through many lesser 2 x 4's in order to find a few quality specimens. And then I post on Facebook about what I endured trying to find those awesome 2 x 4's, in that public lumberyard, before someone else got them first. But I persevered, and have the beautiful lumber to show for my efforts. Now, suppose I need a few 2 x 4's, but instead of going into the public lumberyard, I decide to harvest some of my fine trees and mill them into lumber myself. Still end up with beautiful boards, but when I get on Facebook to post my photos, do I have a little more to be proud of then if I had simply gone to the public lumberyard and sorted through the community stack?  I grew those trees, tended to them, nurtured them, and harvested them in such a fashion as to yield beautiful results. I have an idea about what the lumber in the public yard went through to become great boards, but I had no hand in it....I simply knew how to sort through the stack.

Both efforts will yield great results, and I have actually done both....but one provides me a greater satisfaction than the other.

[Slip Sinker]

Ok , let's stir this up a bit,  not one management style will work for all bodies of water,

First of all I didn’t write the article … It was basically written to improve the overall fisheries by developing studies and conclusions to improve an overall declining fishery the past decades by improving or amending antiquated regulations and fishery practices in Missouri.

I live in Michigan with 11,000 lakes… I know first hand regulations don’t fit every governed BOW. There are just too many. Considering 25 panfish per day is a blanket regulation for all 11,000 lakes. That regulation alone will not fit everybody of water in itself.

The study proclaims that the decline in panfish size and quality is due to over harvest and suggests slot limits and lowered creel numbers. That being said it is a given the first group of fisherman to jump all over this is the catch/keepers. Yet if you think about it the studies and article were written for them not trophy hunters or catch/releasers. They are the majority of license holders. The solution is to immediately reduce creel numbers to raise the eventual average size of the B’Gill. And we all know the meat on a bluegill is increased exponentially as its length is increased. All positive … catch fewer fish with more meat. I don’t understand the argument. I like what Missouri is doing it would project positive results for every fisherman not just catch and keep. Texas has proven just that with their LMB slot limits… It has moved forward in a positive direction. I wish my state would follow.

If a study suggests in your state that overall declining quality of fishing was because of overharvest and nothing was being done about it at what length would a catch/keeper jump lakes because the avg size was in the decline and too small. Should the states DNR allow to even let that happen? As we as license holders should not allow.

With the expressed interest in B’Gill lately it’s just not a harvest and eat fish anymore… the direction B’Gill fishing is moving is in the direction of a true game fish also… I like that. With its gaining popularity I’m in agreement also with any regulation to benefit the catch/keeper as well as the catch/releaser.

My personal management style depends on the body of water I'm on, yes I care about the size of fish I catch and catching big fish is more fun than catching little fish, and I do not want to destroy the resource but on the other hand you have got to remember that this is a renewable resource.

If you read the article carefully studies show declining sizes through time…regulations are being proposed to curb and reverse that decline. The renewable resource is being fished down by advanced and refined shared fishing processes accelerating that decline. Just a few knowledgeable anglers could drastically fish down a system leaving all anglers dissatisfied in any body of water.

I raise trees at my farm and the big trophy trees are the mature trees and those are the ones that are ones that are at the end of their life cycle and therefore they are the ones that need harvesting

Just the reverse is needed… these are fish...the big ones need to be put back in the water especially the males. These are the soldiers mainly responsible to pass on the big B’Gill gene. Who doesn’t like big gills!?  They fertilize the eggs, and guard the nest from any lesser form male. They suppress the reproductive urge in smaller male fish to devote their energy for growth just as Tony validates.

LOFR I grew up in the Old School Rules of fishing.

“Keep the big ones because they are going to die anyway throw back the small ones they need to grow to replenish the stock.”

 When in actuality big ones are more easily filleted verses the small ones.

What is the minimum length of a gill that you prefer on the electric knife?

Trophy hunters need to bite the bullet and cough up the cash to produce their own pond  and control the population of the bass to bluegill ratio, control the feeding program , and control the fishing  pressure  to guarantee that they will have trophy fish every time they go fishing, you know , just like Richman Mills.

This is the part I really don’t get… the B’Gills belong to anyone that pays his or her license. If one chooses to release instead of catch/keep that is their own right of choice as resident of their state. The catch/release fisherman is usually a conversationalist such as i that replenishes the environment better or just the same as first encountered. Why would you suggest removing catch/release from the game. They take nothing away from the catch/keep fisherman.

I try to benefit the sport anyway I can. Posting a discussion such as this seems only to move in a forward direction… even just for knowledge base.

[DAVID L EITUTIS]

HOW TRUE SLIP !!!!! ESPECIALLY when ya go outta state and support another states DNR, Seems only fair to me sepcially with the ridiculous rates they charge for outta state liscenses......

[Slip Sinker]

believe it or not i have never paid for an out of state license yet... i would love to fish Florida eventually as a regular routine somewhere in the near future.

[carl hendrix]

ok; from a country boy; point of view...as a kid growing up;; we had horses; cows; hogs; you name it. to get a better breed of  animal; you had it bred to; a really good blood line; and hoped ; its young was a exceptional  offspring ! so; why not in fish as well?? seems logical doesnt it??  the down ; side of genitcs is;; once they get- just so old;; it has a reverse effect on farm animals;; causing off spring; to be lesser.. ( good thing to know; in case you guys didnt ).. so;; when would it be ( safe) to harvest; bigger ; male blue gill?  how do you  recognise; when their time is done??     and about this tree thing;; Tony; and LOFR;; if yo uguys ever find out where I can get some;; paw-paw trees;; let me know;; I want a couple !!  in case you didnt know it;; paw-paw trees; grow a banana type fruit; full of seeds;; the Lewis and Clark; expedition;; survided  on them for a long period of time !!

[Slip Sinker]

Carl i was an aquarist and i raised African Cichlids fish as a hobby for years... i was literally devastated when my choice breeding pair of Electric Yellow Labs finally expired.. their genes were exceptional. they passed on top tier fry till their last days. i believe that would be the same in any fish even B'Gill.

[Tony Livingston]

Oh yeah, I've eaten many a paw-paw!

[Slip Sinker]

i had no idea what that was...

[Slip Sinker]

further of my research indicates that once the damage is done it becomes more of a situation to fix than the effort required to prevent the problem.

[Lord of the Fly , Rods]

Ok , there is a new school of genetic thought out there that yall bluegill genetic scientist might need to look into, those big males are big males because they haven't been caught yet,and are passing on their genetic traits , well let me tell you a secret, those big genetic males have procreated with females that also have  the same big genetic chromosomes,that they received from their male contributor,  and it takes two to Tango,   so yall need to not harvest the big females either.  As a mater of fact all Bluegill have these genetic , what they need is age to achieve there maximum potential so if I was a Trophy Fisherman I would strive to let them achieve their maximum potential before I tried to harvest them ,and if that means not harassing the wildlife  by catch and release  and accepting the mortality with that practice, that's what you should strive for, you can't have your cake and eat it too.Let me ask yall genetic scientist how do you know the difference between the mature fish that have good genes and the mature fish that got fat from having a good life and have never been caught ? Bluegill's  need genetics , nutrition and age to become a big bluegill ,so they have genetics  they just need nutrition and age , so start feeding them , get them fat and sassy, then don't catch them till their mature . NOTE; I don't pull off my  tomatoes  off the vine until they are fat and ripe . Big male bluegill had a Moma that contributed half of that big males DNA.  I thought Bluegill Big Bluegill was a Forum to include all schools of thought  to promote a better understanding of promoting  bluegill fishing ,these are my ideas base on my 55 years experience of catching bluegills.   Just a little food for thought . LOFR

[Tony Livingston]

As a point of reference, I don't harvest exceptional females either. But, science has proven that it is the male bluegills who impact the size hierarchy the greatest, not just by virtue of genetics, but by their very presence! A six inch male BG doesn't recognize whether or not the 9" male sitting on a nest in front of him has the genetic makeup to grow into a trophy, he just knows that he's smaller than that guy, and therefore needs to continue growing in order to have a shot at claiming a prime nesting spot and attracting suitable (prime) females. If those nine inch male bluegills are removed by angling, then suddenly there may become no reason for that little six incher to continue growing, or at least he doesn't have to exceed nine inches....he's a lot closer to being the largest size class of male present strictly by virtue of eliminating the competition!

Studies have shown where sub-dominant (smaller) male bluegills have become mature and sexually active in just a COUPLE WEEKS after removing the dominant males from the environment. Nature will not tolerate a vacuum, she will promote those smaller bluegills to breeding capability to ensure survival of the species, NOT to try and grow larger. Once a BG becomes sexually active, their growth slows dramatically. That's why current thinking advocates for release of the largest size class of male bluegills. Just a half dozen female BG will provide enough reproductive material to sustain the population of a one acre pond, and while they do contribute genetic material, the simple fact is it is the males, not the females, who play a role In determining the size hierarchy.

I think some of the confusion revolves around the use of the word "trophy". There's a huge difference between a big bluegill, and a trophy bluegill. The recommendation to release the largest size class of males comes from scientific study intended to ensure viable populations of big bluegills, NOT trophy bluegills. Obviously the definition of trophy is variable, and dependent upon many things. What I might consider a trophy class  might just be a big bluegill to some. Trophy bluegills are in a class far removed from big bluegills. I've fished lots of water that contained big bluegills, but have never had the privilege of fishing where what I would consider trophies, are plentiful. I tend to see it like building a racecar....the car needs a multitude of components in order to go fast. But even after all those components are assembled there is still room for improvement by applying a good tune, to ensure all of the other components are working to their highest potential. Tuning is like genetics....it's the icing on the cake, the final nudge needed to promote greatness. I've grown 10-11" bluegills right from stock purchased off the traveling fish truck....certainly not likely to have optimum genetics...but they weren't trophies in my opinion. They were just big bluegills.

Great water quality, abundant forage, adequate predator/prey ratio, protection from harvest....all of these are needed to grow both large bluegills as well as trophy bluegills. That's why they are more important than genetics, from many standpoints. Genetics is what will nudge a big bluegill over into trophy status. But most state agencies, and even anglers themselves, are far more concerned with big bluegill populations than they are trophy gills. That's why it's important to release those larger males...not so much for genetics, but for the role they play in subduing the smaller fish. I don't believe trees and tomato plants work that way.

And I do in fact know several folks who do NOT fish in their trophy BG ponds. Matter of fact, we're stocking one of our ponds this spring with an eye towards harvest...a food for the table, pond. One where we can go and catch, not trophy bluegills, but big bluegills for the dinner table. That way we can provide the potential trophy pond some peace and quiet.

Here at BBG we ARE open to all methods and harvest strategies, provided they are done in a legal manner. But we also consider ourselves stewards of the environment, as well as a library of sorts regarding cutting edge and current practices where bluegills are concerned. We do advocate for harvesting wisely, and respecting the resource. We can be more than photos...we SHOULD be more than photos.