Posted on 06/17/2015 7:53:48 PM PDT by nickcarraway
A study of lakes in Connecticut reveals that recreational angling pushes largemouth bass to evolve.
Fishing a lake may, over time, make the fish in that lake harder to catch. A new studysuggests that recreational fishing, aka angling, causes evolutionary changes over the course of decades. Largemouth bass living in waters popular with anglers have been adapting to become less active. New generations of increasingly timid fish may eat less and be less likely to bite.
“When your grandfather told you the fishing was better back in his day, it’s possible he was right,” says Jan-Michael Hessenauer, who reported the finding online June 3 in the journal PLOS ONE.
Now a graduate student at the University of Connecticut in Storrs, Hessenauer caught his first fish as a child, using a wooden pole his dad made. He spent his youth fishing for fun at his uncle’s cottage on a lake and in the cold streams of northern Michigan.
In the fall of 2012, a year after coming east, Hessenauer went fishing for largemouth bass in Connecticut’s Amos Lake and Gardner Lake — for the sake of science, not sport. In the early part of the 20th century, people ate their catches, but recent decades have seen the rise of catch-and-release, and now most fish are thrown back.
Curious about how this activity has affected the bloodlines of the fish in those two lakes, Hessenauer captured some baby bass using nets and electric stunners. For comparison, he also collected babies from two reservoirs owned by water companies that have long prohibited fishing. After raising fries from both sites in an isolated pond for 10 months, he and his team then measured how much oxygen the fish consumed when at rest. This provides a proxy for metabolic rate, which relates to how active a fish is.
The lake-born bass had slower metabolisms. Animals tend to inherit their metabolisms from their parents, so this discrepancy between reservoir and lake fish could be an example of evolution in action.
For a fish living in a placid reservoir undisturbed by anglers, having a high metabolism — and thus a more aggressive demeanor — would be a good thing. Bolder males are better at defending their nests from other males and critters intent on gobbling up their eggs or newly hatched young. Their protected offspring would be more likely to survive and grow into bold males that are themselves more likely to pass on their DNA to their offspring.
But for a fish trying to get by in waters teeming with sportsmen, being aggressive could actually be a bad thing. A pugnacious fish would be more likely to strike an angler’s hook and disappear — leaving its progeny defenseless for a short time or forever, depending on whether the fish gets thrown back into the water and whether it survives the ordeal. Such fish would also be more likely to go after a wriggling worm on a hook in pursuit of food outside of the spawning season. In short, fishing pressure allows the meek to inherit the lake.
“The fish adapt in the face of a new predator, humans, and evolve to become less aggressive,” said David Philipp, an angler-turned-biologist who chairs the board of directors for the Fisheries Conservation Foundation in Champaign, Illinois.
Philipp spent decades showing that fish can be bred to become more or less aggressive. In the 1980s he invited anglers to cast in ponds he had seeded with bass. When fish that were caught three or more times were mated, generation after generation, their family line gained a higher metabolism. Fish that were caught once or not at all gave rise to another lineage with a lower metabolism. The new study is the first to suggest this change in metabolism under natural conditions–though Hessenhauer can’t be 100 percent sure that differences between the lakes and reservoirs other than fishing levels could be to blame.
What the change means for the lifestyles of bass remains an open question. Creatures born with slower metabolisms tend to mature and give birth at a younger age.
Like lions or eagles or crocodiles, bass are apex predators at the top of their environments, so changes in the diets of bass could also have a trickle-down effect on the other inhabitants of their ecosystem. Hessenhauer and his colleagues calculated that a 2-pound (0.9-kilogram) fish from one of their angled lakes would eat about 0.5 fewer Calories per day of the fishing season than reservoir-born fish. That means more of the bass’s prey can survive. Which means less of the prey’s prey can survive. And so on, and so forth.
“Although this change in caloric consumption might seem small, once you multiply it by the number of individuals in the food web it has the potential to make some relatively substantial changes,” said John Post, a biologist who studies trout at the University of Calgary in Alberta, Canada, and wasn’t involved in the new study.
Whether other kinds of large fish in other lakes in other places are evolving is unknown. Bass in New England may experience more pressure to adapt than their peers elsewhere. Species inhabiting lakes in the South, for instance, can have a longer breeding season that provides more chances to reproduce. They also tend to live in larger populations that dilute the impact of fishing on each fish.
“We need more research to see how things differ by location,” said Hessenhauer. But even though the impacts of evolution on lake fish remain far from definitive, he encourages managers of lakes to consider how much pressure is being put on their fish. The big catch-and-release tournaments popular with anglers may, in the long run, have repercussions on the tournaments themselves.
Bwahahahaha!
This is poppycock. Bass attack what looks like food and evolution has nothing to do with it; it is the nature of the bass. I fly fish for bass and it has to do with how good I present the eats to the fish. I do fine.
I was wondering where you get your 1/16 ounce line. Seems a little light to me. :=)
That was 16th oz Roostertails...6 lb line...My bad....*L*
I guided trout fishing for many years in the Great Smokey Mtns Nat’l Park...
Not only did we catch trout, but there was Rock Bass, Smallmouth Bass and what we called “hornyheads” a kind of chub that grew to about 10 inches...
They were good eating in the spring only...
maybe the slower, more timid fish haven’t gotten caught at the rate of the wiley crazy fish, or some such nonsense,.
Forget lures! Try throwing sticks of dynamite into the water while standing directly on the shore - or maybe even while sitting in your parked car. Don't trouble yourself about getting a fishing license - you're a sportsman! If any nosey game warden should appear and question your activities, mouth off to him! Oh, and better get liquored up, first!
Follow my advice, and I guarantee you an unforgettable vacation experience in Oklahoma!
Regards,
*ROFL*
“I guarantee you an unforgettable vacation experience in Oklahoma!”
LOL,
Yes, with a free visit and tour to the local jail.
I'm a bass player and my bass has never attacked anything.
Small mouth bass from a river are THE BEST! Lots of fight in them. We would use the lightest line (4 to 6 lbs) and lightest rods possible casting a small “Mister Twister” - little yellow rubber thing with the wiggly tail and a flasher. They eat crawdads - so that is a good color too. Cast up and across the river, get next to the rocks and into the backwater behind the big rock.
Get your tackle once you are down there at a local shop - they’ll know what works.
EPA to issue order to ban transgum in worms! ;^}
What idiocy.
Its called fishing pressure. A lake with a lot of pressure MAY be tougher to catch fish in. Not always.
But as fish change their behavior so too do anglers change their tactics and tackle.
Try a Senko. It’s “idiot” proof.
If that fails, throw a spinner bait.
It’s obvious that decades of catch-and-release have allowed the bass to tell their nightmare stories of micro-agressions to their chirren, who are reacting by becoming slobs who won’t fight. It’s not like they can burn down their neighborhood or something. Logical conclusion: watch the little squigglies on the ends of those funny lines go by and just flip ‘em off.
And, apparently, less aggressive bass have an advantage. Must be pretty heavily fished area.
Thanks to all of you guys. I KNEW the freepers would know what to do! And thanks for the links. Around the 6th of July I’ll let you know how I did.
One more question. I assume I cast and slowing reel it in keeping the lure a foot or two under water?
I like to cast it upstream and reel it in slow - just enough to keep the spinners moving. They like to be up against the rocks to hide. And probably more near the bottom. That time of year it might be warmer and they may like the deeper pools - but I don’t know. Even then though - fish on the edges of the current. The fish are in the calm water against a rock, waiting for the current to bring them a meal.
Again - talk to the local tackle shop.
Thanks.
Smallmouth Bass love Helgramites. They live under rocks in the creeks. But as far as tackle a nice six foot spinning reel with six pound line and some inline spinners such as Rooster Tails or Mepps Aglia should get you started. I could spend all day discussing this but these are just the basics. LOL. You can fish from bank. If it is shallow, wade in the shallow and throw into the deep pools.
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