A highly aggressive species of fish has been found in Lake Tahoe, and environmental scientists are afraid the nonnative invader will gobble up native fish and ruin decades of work to improve water clarity, researchers said Tuesday.
A smallmouth bass was recently spotted by a team of researchers from the University of Nevada, Reno. The native of the Mississippi River basin was 13 inches long and ripe with eggs, indicating that the fish are reproducing and have probably already spread around the mile-high lake.
"It really shocked us. You can think of it this way: There is a new bully in the neighborhood," said Sudeep Chandra, a university limnologist who was working with the California Department of Fish and Game on a study of invasive species when the discovery was made six weeks ago. "It's a type of species that we know when introduced into cold water lakes tend to do very well and they tend to prey on native species."
The Department of Fish and Game has been working with Chandra and his team of researchers in an attempt to remove nonnative species from the lake. Their joint study found that introduced species such as largemouth bass, bluegill and catfish have hurt water quality by excreting nutrients that cause algae blooms. Asian clams have caused similar chaos.
Smallmouth bass, known scientifically as Micropterus dolomieu, aren't rare. They have been moved all over the United States since 1825, when construction of the Erie Canal extended their range into central New York state.
The problem is that they are ferocious predators that are likely to feed on Tahoe's native redside dace, suckers and chub.
Studies of introduced smallmouth bass have already shown that they have devastated trout populations on the East Coast. Tahoe's lake, brown and rainbow trout could also be in jeopardy. The alien fish could hamper efforts by the U.S. Fish and Wildlife Service to re-introduce native Lahontan trout to the Sierra lake.
The joint study documented a 58 percent decline in native fish caused just by largemouth bass, bluegill and catfish. The smallmouth bass could make things worse, said Kevin Thomas, a Fish and Game environmental scientist who co-wrote the invasive species study.
"We've had reports of smallmouth bass before, but now we've 100 percent confirmed its presence in Lake Tahoe," Thomas said.
Water quality is a big deal at Lake Tahoe, which has gotten warmer and murkier over the years. The clarity of the second-deepest lake in the nation has steadily worsened since 1968, when scientists began measuring how deep a white disk remained visible from the surface.
It was 64.4 feet last year, the second-lowest level ever, according to the UC Davis Tahoe Environmental Research Center, which is in charge of the annual measurements. That's compared with 102.4 feet 43 years ago.
E-mail Peter Fimrite at pfimrite@sfchronicle.com.
I find it interesting how they believe bass are the cause of poor water clarity?
Not to mention they found a spawning bass 6 weeks ago!
They're welcome to load them up in a truck and take them to Belleville lake :P
Having spent some time in the Tahoe area, it is a beautiful area and the people there are passionate about protecting it. Can't blame them for their zeal. Lake Tahoe averages, averages 1000 ft. deep with the deepest part of the lake being a little over 1600 ft. deep. There is enough water in Lake Tahoe to cover the state of California with one foot of water. It never freezes because of its depth. Temperature ranges from 44 to 68 degrees. It has 72 miles of shoreline.
In my trips out to Tahoe, I've heard that there are those who claim that there were smallmouth in it, especially down at the south end. It's rocky looking smallie water around the whole lake. There are bass in reservoirs near the lake that people could catch and carry. Despite my love for smallie fishing, I can't blame their concern over people putting non native fish in the lake.
They don't use any salt on any of the roads out there because of their concern for the lake and they get a lot of snow.
Tahoe is considered a high dessert. Very little rain, idyllic temperatures during the summer, no flies or mosquitoes, etc. If you have never been there, put it on your bucket list.
If they are willing to pay my way, I'll truck on out there and help alleviate the problem. ;D
Road trip!
eyes closed fo sure, i say the more smallies the better ;D
I can't imagine Smallmouth causing water clarity issues. Especially of a fish that thrives in the clear waters of LSC and Erie. I do understand their concern over a non-native species of fish, however their fishing will get better. Imagine a B.A.S.S. Event or FLW Event on Lake Tahoe. I have been out there several times and love the area. I would love to go back and fish for smallies, especially if they get big. The lake never freezes so that means the fish could grow all year round. Next world record smallie could come out of that lake in years to come. I actually wonder if the smallies got in there through tributaries that flow into the lake from other lakes in the area. I am sure more research has to be done.
BD ;D
Quote from: UAWBigDog on August 20, 2011, 09:13:43 PM
I can't imagine Smallmouth causing water clarity issues. Especially of a fish that thrives in the clear waters of LSC and Erie. I do understand their concern over a non-native species of fish, however their fishing will get better. Imagine a B.A.S.S. Event or FLW Event on Lake Tahoe. I have been out there several times and love the area. I would love to go back and fish for smallies, especially if they get big. The lake never freezes so that means the fish could grow all year round. Next world record smallie could come out of that lake in years to come. I actually wonder if the smallies got in there through tributaries that flow into the lake from other lakes in the area. I am sure more research has to be done.
No 2 strokes allowed on Tahoe. BASS couldn't get every competitor into a 4 stroke boat for an even there.... logistical nightmare.
BD ;D
Are Lake, Brown, and Rainbow trout native to Lake Tahoe?
About the only fishing I've seen them do on Tahoe is for a salmon they call a mackinaw. They fish them deep and the pictures always show them with their stomachs out of their mouths.
Lots of people out in the Western states consider bass to be an invasive species on many waters. Some people also think if you don't catch trout on a fly only, you're some type of loser. Some people probably even still believe the moon is made of cheese. Different strokes or something or other.
But anglers shouldn't have their own private stocking programs either. Not a good idea.
I used to go swimming in Lake Tahoe when I was a child. The water was pretty clear there. Bass are the most fun to fish for, but in California they do tend to take over, so even though it is no great loss from a fisherman's standpoint to lose some catfish, from an ecological standpoint it is a shame.
I don't think they have trout in Lake Tahoe but the water is cold enough.
Any introduction of a new species should be considered carefully and often not done. But we humans sure have introduced a zillion things in a zillion places.
Quote from: Waterfoul on August 20, 2011, 02:44:31 PM
If they are willing to pay my way, I'll truck on out there and help alleviate the problem. ;D
May have to get some bigger Shot weights Waterfoul!
If it doesn't freeze because of the depth, why does Superior freeze? Well used to I think, Global warming and all.
The average temp for Tahoe stays above 44 degrees. Plus to average 1000 feet deep you don't find much shallow water. I'm sure they get a little shoreline freeze, but a lot less than you would think.
Out there they don't use salt on any of the roads. They do require chains to go over many of the passes, and if you don't have them they turn you around. They get so much snow that they can't just push it off the road. They plow to the middle and scoop it, or use a big snowblower type truck.
Even though they don't use salt the roads get down to asphalt and dry in a hurry, because when it snows it snows, but then it gets bright blue and intense sun. With as much sun as they get the black asphalt melts the residual pretty fast. They rarely get a cloudy day if it isn't snowing. Most days are bright blue skies. All this direct sun during the winter, and the amount of water in the deep lake, (enough water in Lake Tahoe to cover the whole state of Cali with one foot of water.) keeps the shoreline almost iceless. It's an idyllic area.
The Tahoe area is considered a high dessert. At lake level you are at 6,000 ft. You'd be surprised at how much difference the elevation makes as you drive up to one of the many ski areas around the Tahoe bowl. Snow depths really vary from lake level to the ridges.
A picture from early June of this year and a You Tube video that shows how fast the drop falls off.
http://www.youtube.com/watch?v=c_fY7vluqHo
Quote from: chrisvmo on August 26, 2011, 03:22:12 AM
Quote from: Waterfoul on August 20, 2011, 02:44:31 PM
If they are willing to pay my way, I'll truck on out there and help alleviate the problem. ;D
May have to get some bigger Shot weights Waterfoul!
I can pour up to one ounce!!! Let me at em!
Oh, and I didn't see any of those terrible small mouth in that video....
They're in the shallow end.
When they said 'high altitude dive' I was expecting someone to be jumping off a cliff into the lake!
Lake Superior is one big lake. It's average depth is about 480 feet, whereas Tahoe averages 1,000 ft. There is enough water in Superior to cover all of North and South America with one foot of water. Tahoe holds enough to do the same to the state of California.
As to its freezing: according to a study by professors at the University of Minnesota Duluth, Lake Superior may have warmed faster than its surrounding climate.[13] Summer surface temperatures in the lake appeared to have increased by about 4.5 °F (2.5 °C) since 1979, compared with an approximately 2.7 °F (1.5 °C) increase in the surrounding average air temperature. The increase in the lake's surface temperature may be related to the decreasing ice cover. Less winter ice cover allows more solar radiation to penetrate the lake and warm the water. If trends continue Lake Superior, which freezes over completely once every 20 years, could routinely be ice-free by 2040.[14] These warmer temperatures can actually lead to more snow in the lake effect snow belts along the shores of the lake, especially in the Upper Peninsula of Michigan.
Ok now that I have had a history lesson on lake tahoe. I'm still shocked that bass cause poor water clarity?
I personally find this hard to believe.
My guess is the declining water clarity is more a cause of the developwmnts around lake tahoe, lawn fertilizers, global warming and more algea.
Why is the bass getting the blame. What do bass do that trout don't do?
Orvis folks like their fish in the seven inch range and the bass just get too big for their 9 weights. ;D