Big Indiana Bass

Bass In the News

• Nanosilver Migrates from Treated Fabric During Washing - An interesting article that mentions a study of silver nanoparticle effects on juvenile largemouth bass toward its end.
• Bill Dance thrives on saltwater - For those who like the bass man from Tennessee.
• Cold snap possibly helped native fish - Lots of dead fish in Florida, but it might be a good thing for native largemouths.
• February kicks off big-bass time in East Texas - Good to know it's pre-spawn somewhere in the U.S.
• Bigger bait is the key to catching bigger fish - At least if you're shiner fishing in Florida this time of year.
• Choke Canyon Sends 15-Pounder to Toyota ShareLunker Program - Another Texas giant caught over the weekend.

MN Length Limit Studies

I've posted about maximum length limits a time or two on this site, and now we have some new data out of Minnesota that looked at them closer. Mandatory Catch and Release and Maximum Length Limits for Largemouth Bass in Minnesota: Is Exploitation Still a Relevant Concern? by Carlson, et al. and set to be published in the Feb. 2010 issue of the North American Journal of Fisheries Management compared results from 9 lakes against each other, six with a catch and release only policy and three with a 12" maximum length limit.

From the Abstract: "We evaluated the response of Minnesota populations of largemouth bass Micropterus salmoides to implementation of 305-mm maximum total length (TL) limits (three lakes) and mandatory catch-and-release regulations (six lakes). Responses were compared with population trends observed in nine reference populations where largemouth bass harvest was regulated by prevailing statewide regulations. Increased harvest regulation generally improved largemouth bass size structure, but statistically significant improvements in size structure indices were detected in only a few individual lakes. Increased regulation of harvest did not appear to influence electrofishing catch per unit effort (CPUE; fish/h) of largemouth bass less than 381 mm TL. Electrofishing CPUE of fish greater than or equal to 381 mm TL (CPUE-381) generally improved after more stringent harvest regulations were in place, but improvements were only significant for two of the three lakes where a 305-mm maximum length limit was implemented. With the exception of one lake, increased harvest regulation did not appear to reduce largemouth bass growth rates. Improvements in size structure and CPUE-381 were rarely observed in reference lakes. Our results suggest that despite increases in voluntary catch and release of largemouth bass, angler exploitation is still an important factor regulating size structure in some Minnesota lakes, and more intensive harvest regulations can improve size structure in some populations."

Cover, Turbidity and Smallmouth Bass

A new study out looks at the importance of these two items and how they affect food selection in smallmouth bass. Effects of Turbidity and Cover on Prey Selectivity of Adult Smallmouth Bass by Carter, et al. found:

1. In clear water without cover, smallmouth preferred gobies over golden shiners and avoided northern crayfish.
2. As turbidity increased, the three species were all neutrally selected.
3. When cover was present, smallmouth bass selected golden shiners preferrentially over both gobies and crayfish in both clear and turbid conditions. This is possibly due to the shiners being a more open water fish and hence easier to find or capture. Both gobies and crayfish attempted to hide when cover was present.
4. Turbidity decreased the hourly consumption rate of smallmouth, which appear to be more negatively affected by such conditions when compared to largemouth bass.
5. Their study suggested that smallmouth could have difficulty feeding for up to two days following a turbidity pulse.

Fly Fishing: A Real Pain In the ...

Shoulder, not to mention the elbow and wrists. Turns out frequent fly fishermen suffer frequent pain from their endeavors. An interesting study documenting the upper body maladies associated with fly fishing.

Upper Extremity Pain Seen With Fly-Casting Technique: A Survey of Fly-Casting Instructors

Yearly Water Temps, Precip. and Solar Energy

 

Courtesy of Cicero Weather 

Hook'em or Shake'em: New Insights

It's the age old tourney dilemma, to hook fish in practice or to shake them. You'll find lots of opinions on message forums concerning this topic, as well as in magazine articles and professional bass angler interviews. It seems a large component of the pros say to shake'em, not wanting to stick fish they will need the next day or two of a tourney. But to this point it has been a purely personal decision based on experience and opinion. Finally, science takes a peek at this problem.

Appearing in the Sept. 2006 edition of the Journal of Fish Biology, 'Effects of angling on feeding by largemouth bass' by Siepker; Ostran and Wahl tested this out in the lab. Unfortunately, I don't have a journal subscription to the above mentioned reference journal, nor do I feel compelled to pay the $50 fee to view this article, but the abstract provides us with a good idea of the testing and the results associated with this experiment.

Largemouth bass were ran through a series of tests to determine how soon after being caught they would resume normal feeding. Fish appear to have been caught by hook and line, and then ran through two scenarios. The first was being held for a period in containment and then probably weighed or measured prior to being "released" to feed again. This would represent a bass held in a tourney type scenario. The second path was bass that were caught by angling but immediately "released" so they could recover and be observed for feeding resumption. The last group would have been the control group, fish that were most likely electrofished and then placed into their respective homes to be observed for feeding. The results  play out as you might expect, other than the interesting recovery times associated with each scenario.

The first to recover were the control group, which would resume normal feeding somehwere between 0-2 hours after release, almost unaffected. The next to recover were the immediate caught and released bass. This would be very similar to a practice day where you might hope to come back to the area and catch that same fish within the next day or two. These bass typically only needed between 6-11 hours to fully recover to the point of normal feeding resumption. In other words, in most cases they'd be ready to bite again the very next day.

The last group, the tourney simulated fish that were held in livewells after being caught and released at some later point, took longest to recover as you might expect. Interestingly though, the average time to resume normal feeding for these fish ranged from 13-18 hours. Again, these fish could most likely be caught again the very next day. Keep in mind that these were averages based around normal standard deviations, so while this would account for the majority of all bass tested, there were probably a few 'outliers' that ran longer or shorter for each group. Each fish is an individual and will react accordingly. That said, the results are pretty cool.

So shaking fish off in practice would appear to be a largely psychological thing based upon an anglers belief, confidence level or perception. Additionally, this in part explains why tourney release areas can be such good fishing spots, and why many times they are made off limits. This also explains why running to other ramp locations on a large lake with multiple ramps can be a good tourney strategy. Every angler has to fish and strategize around his own comfort level, and this study shouldn't necessarily change whatever that strategy is for you. However, it does chip away at the reasoning of those anglers who profess shaking fish off is the correct practice strategy for tourney fishing. 

More Asian Carp Science

I received a copy of this letter today which I found very interesting. I would suggest paying particular attention to the last paragraph, keeping in mind what we currently know about the effects of zebra mussells and snakeheads after living through their introduction to our waters and the resulting media attention/frenzy. You can search this site for some posts on those topics.

One thing that has been showing up in the media recently is that these fishes are river fish and not lake fish, and thus do not threaten the lake. That is barking up the wrong tree.

Bighead and silver carp are pelagic lake fish that happen to spawn in rivers.  When the fish were brought to the United States, that is one of the reasons that many people thought they would NOT live here – our river systems do not have the associated floodplain lakes that dominate the floodplain of the Yangtze River.  The last time I spoke to Yi Bolu (a pioneer in Asian carp research in China, and probably the most respected scientist in the field) before he died, he remarked "I STILL can't believe the carp do so well in North America without the access to lakes."  Asian carps in rivers in the USA live in low velocity areas on channel margins, lake-like low velocity river sections, and, when they can access them, associated floodplain wetlands.  They only use the higher velocity and turbulent areas for spawning and for migration to spawning areas or conduits between low velocity areas.  The fact that they can do so well in river systems without much lake access is a tribute to the adaptability of these fishes.

Asian carps are established in many lakes and reservoirs around the world.  When they are established, the adults are usually PELAGIC LAKE DWELLERS, not river dwellers, except to spawn.  

For example, about two weeks ago my colleague Dr. Tatrai of Hungary, who is working on trying to figure out ways to catch these fish out of Lake Balaton, caught dozens of huge silver and a few bighead carp from the open lake.  Lake Balaton is the largest lake in Eastern Europe, about 1/5 the area of Lake Erie, and is considered oligotrophic to mesotrophic. Counterintuitively,  the carp seem to live in the portion of the lake where plankton abundance is the lowest.  We don't know why this is so, although Dr. Tatrai has some hypotheses that seem astute. Nevertheless, it seems pretty clear that silver carp could do very well in water that is substantially less productive than Lake Balaton, because the fish in Lake Balaton are very, very fat.  I have seen thousands of silver carp from US Rivers, from South Dakota to Illinois to Louisiana, and I have never seen a single silver carp in the USA with condition factor as high as the AVERAGE Lake Balaton fish, or as large as the average fish captured by Dr. Tatrai (about 15 kg on average).

We don't know where the cutoff is in terms of productivity, and the Great Lakes, since the invasion of the mussels, are much less fertile (based on chlorophyll concentration) than even the most oligotrophic portions of Lake Balaton.  The portion of Lake Balaton where the carp are mostly caught  is similar in chlorophyll concentration to lake Erie just before the zebra mussel invasion (usually about 10 ug/L or a bit less).  Also, for reference, temperature regime in Lake Balaton is fairly close to that of Lake Erie.

We don't know for sure whether silver and bighead carp will cause substantial problems in the Great Lakes or not.  That is a very hard question to answer, and one could argue either side of that question convincingly.  There has been a tremendous amount of over-the-top hyperbole about what Asian carps are going to do the fishery of the Great Lakes.  But to say that they are "river fish" and not "lake fish" is incorrect, except that they are thought to need rivers for spawning and for a couple days for the incubation of the eggs and young larvae in the drift of the river.

Duane Chapman
Research Fisheries Biologist
USGS Columbia Environmental Research Center

Fishery Science In the Classroom

Since we reference so many studies on this site, many of which are carried out by graduate students and their professors, I thought this little piece was both timely and interesting.

UC Davis students get practical study of 'fish biology'

Asian Carp Controversy: In the News

If you've been following the news at all, you've probably seen some of the stories concerning Asian carp and the lawsuits between states that have been popping up. For those that haven't, here is a sampling from a variety of sources:

• Michigan AG to hold news conference on Asian carp - The state of Michigan is preparing to sue the state of Illinois over stopping any canal breach.
• Michigan Sues Illinois Over Asian Carp - The suit gets filed and goes straight to the Supreme Court.
• Fish Kill: Snapshots of Beginning - The start of a well detailed blog on the effort.
• Fish Kill: Day 2 - Not all Chicagoans are thrilled with trying to stop the carp.
• Fish Kill: A Hall of Famer's Take - Another opinion on the subject.
• Fish Kill: A Chicago Biologist's Help - New websites appear to address some of the information being spread.
• Fish Kill: Official Wrap-up - Another website and the official summary from the Asian Carp Rapid Response Workgroup.

Finally, several of our own IDNR biologists were sent over to help with the project. For a first hand glimpse and summary from one of our own, I give you the following:

ASIAN CARP ERADICATION ON THE CHICAGO SANITARY AND SHIP CANAL IN ILLINOIS

The permanent electric fish barrier (barrier IIA) on the Chicago Sanitary and Ship Canal (CSSC) was to be shut down for a few days for scheduled maintenance late in 2009.  In the summer of 2009 environmental DNA (eDNA) indicated that Asian carp may be in the Lockport pool of the CSSC and positioned very close to the permanent barrier.  Although intensive fish sampling using traditional sampling gear could not verify the presence of Asian carp, most felt the eDNA was a true indication of their presence in the reach of the canal.  The fear was that when barrier IIA was taken off-line for maintenance, the Asian carp present in the area would move above the barrier and become trapped between barrier IIA when it was turned back on and the aging original electric barrier (barrier I) located nearly ¼ mile above IIA.  Barrier I does not emit as strong of an electrical current and therefore is less effective in preventing further movement of Asian carp toward Lake Michigan.

It was determined by a panel of experts that the best course of action to prevent movement of Asian carp further up the CSSC was to perform an eradication in the CSSC beginning just above barrier I and continuing downstream to the Lockport lock and dam (approximately 6 miles).

As the plans for the eradication began to form, further eDNA analysis indicated that Asian carp were present north of the electric barriers in the Cal-Sag channel.  The fish were potentially only 6 miles from Lake Michigan should they elect to go through the O’Brien lock and dam and through the Calumet River.  Despite this further evidence it was still felt that the eradication in the Lockport pool was important to not allow further Asian carp above the barrier.

Four fisheries personnel were approved to assist for up to 5 days in the eradication project: Sandy Clark-Kolaks, Debbie King, Jamie Smyth, and I.  This was truly a basin wide project showing the importance of keeping another aquatic invasive species from entering the Great Lakes.  Obviously Illinois was well represented in the project with fisheries personnel and their Conservation Police.  Other agencies represented included Michigan, Wisconsin, Canadian agencies, Fish and Wildlife Service, USDA, EPA, USGS, Coast Guard, Great Lakes Fishery Commission, and I’m sure other agencies.  A few other states that could not send personnel were able to provide chemicals or money for the project.  In total, I was told that there were over 500 people reporting for duty for the project.

Most crews arrived for “Operation Silver Screen” on Tuesday 12/1/09 to be briefed on the project, get fitted for safety gear (chemical applicators), and begin preparing for the eradiation.  On Wednesday a fish salvage operation took place to remove desirable fish for restocking at a later time.  Electrofishing is not very effective on CSSC due to the steep channel walls and lack of habitat.  In addition, water quality is likely not conducive to the establishment of a quality fishery.  Few fish were salvaged and quality was perhaps even less than what was expected.  The only noteworthy catches were a 20 inch walleye and a smallmouth bass which were either good at holding their breath or didn’t mind too much living in water composed of 70% effluent from wastewater treatment plants.  Sandy and I participated in the salvage.

For much of the day on Wednesday the 5 shore-based rotenone application crews which included Jamie and Debbie were getting their stations set up and becoming familiar with running the equipment.  By late afternoon everything was in place and all equipment was supposed to be ready to dispense rotenone.

Rotenone application was set to begin at 6pm on Wednesday evening starting at the uppermost shore pumping station which was located just above barrier I.  The equipment wasn’t pressure tested ahead of time and blew a fitting immediately causing a 2 hour delay in the start of the project.  Once rotenone application began at 8pm Wednesday everything seemed to move very smoothly.  USGS applied a dye to the river ahead of the rotenone and tracked the plume in order to instruct the shore application stations when to begin pumping.  Off-channel connecting water and wide areas in CSSC which would not receive the flow of rotenone coming down the channel were treated by boat.  Sandy and I were on boat crews and began our work at 1am Thursday morning and worked until late in the morning.  Jamie and Debbie were on the most downstream shore pumping station and were able to begin pumping at around 3am Thursday.  Shore stations pumped rotenone for 8 to 10 hours.

Rotenone was detoxified using potassium permanganate.  Crews who are normally on Great Lakes tributaries killing sea lamprey were running the detoxification stations.  Detoxification took place below the Lockport lock and dam, in areas where the CSSC was leaking water into the Des Plaines River (it flows adjacent to CSSC), and in off-channel areas where CSSC flow would not flush the rotenone.

Dead fish were required to be removed in the project and I’ve been told that the new rotenone label set to come out soon will require this in all eradication projects.  Fish recovery crews were on the river as soon as fish began being affected by the rotenone and they were on the water at least prior to 1am when Sandy and I began our boat application jobs.  Fish came up very rapidly once the rotenone was applied, but shortly after they thrashed around at the surface they dropped to the bottom (30 foot of water).  An estimated 30,000 pounds of dead fish were collected as rotenone was being applied.  On Thursday afternoon a 20” bighead carp was recovered in the lower reach of the treatment area.  This is the first validation that eDNA was correct in identifying that Asian carp were present in the area.

Crews were planning to be busy cleaning up dead fish from Friday until early the following week.  First thing on Friday (20 degrees) a large contingent of people staged at CSSC to pick up fish.  Dead batteries in boats and frozen wheel bearings were the largest challenges that morning (did I mention how cold it was?).  Very few fish were at the surface or along the shoreline so pounds recovered were very low.  As a result of limited things to do (waiting for fish to bloat and float is about as exciting as watching paint dry) the four of us from Indiana were demobilized on Friday afternoon.

As of writing this summary, few fish came to the surface to be recovered.  Although water temperature in the canal is around 60 degrees (hot water discharge from power plant elevates the temperature) bacterial action did not cause fish to bloat and come to the surface.  Divers in the area of barriers I and IIA reported an abundance of fish on the bottom of the canal that were being feasted on by crayfish, so they are down there but they may never come to the surface.  Illinois was preparing for the recovery of perhaps 200,000 pounds of fish yet less than 50,000 pounds were removed.  Still only a single bighead carp has been found.

Barrier IIA was off-line for just 48 hours and maintenance checks indicated that it was holding up very well in its first 7 months of continuous operation.  The barrier will have to be taken down every 6 to 12 months for maintenance, but obviously Illinois hopes not to have to perform this same operation ever again.  The Army Corps is busy beginning to prepare for the installation of barrier IIB which will be adjacent to IIA.  They expect it will be done in September or October 2010.

Illinois has estimated the total cost of the project to be approximately $3,000,000.  Involvement from the four of us from Indiana was “donated” time to assist our neighbor.  Total costs for our involvement in the project was $3,880 for salaries, $416 for per diem, $396 for hotel, and $308 for gasoline.  Although we contributed a mere $5,000 to the project, I know that Illinois appreciates every bit of assistance provided by Indiana and all other agencies to help on this very important project.

Doug Keller
Aquatic Invasive Species Coordinator

Overwinter Gizzard Shad Mortality

A new study recently published takes a good look at the factors affecting gizzard shad overwinter survival. Overwinter Survival of Age-0 Gizzard Shad in Missouri Reservoirs Spanning a Productivity Gradient: Roles of Body Size and Winter Severity by Paul H. Michaletz reveals just how variable a food source gizzard shad can be in our reservoirs from year to year. Among the findings:

• Fall age-0 demographics did not vary consistently across a reservoir productivity gradient
• The variability in overwinter survivors among cohorts did not consistently decrease with increasing reservoir productivity
• Overwinter survival of age-0 gizzard shad was related to both fall age-0 demographics and winter severity

Michael surmizes that, "There is probably no single mortality factor; rather, multiple stressors probably interact to affect overwinter mortality of gizzard shad. These interactions are likely to operate through both density-independent and density-dependent processes. During severe winters,mortality probably operates in a density-independent fashion, whereas in more moderate winters density dependent processes may be more important."