Vilbig Bass Club Lake Survey
March 21, 1995

Lake Biologist Bob Lusk Surveys Lake Vilbig

Taken from the Bass Club Bulletin, Vol 2, Issue 4, April 1995.

On March 21, Mr. Bob Lusk (the highest priced lake biologist we could find), and Mr. Walter Bassano III (Mr. Lusk's assistant, who appeared far more capable than Mr. Mark Palmer's assistant), with the able assistance of Paul Miles (our August Club President), Marty Tackett (our V-President, Club Expert on Bass, twice Angler of the Year), and David Kern (Past President, Club Medicine Man and Correspondent), conducted the long awaited lake fish survey. The Vilbig Bass Club agreed to pay for this $750 survey from the Stocking Fund.

The survey began at 9:50 AM from the boat ramp at Diamond Lane. Marty and Paul set off in one boat with instructions to seine 5 banks, classify and count each species of fish they caught. They did this by going to a target bank and anchoring one end of the seine there, then taking the gas powered boat and letting out 100 ft. of seine, eventually bringing the other end back to another point on the bank. Marty and Paul would then both get into the water and slowly bring the seine into the bank by hand.

Paul says many of the bass seemed to know that they were being hauled in. They would head straight for the seine, shoot out of the water and over the seine...sometimes four at a time. Since the mesh was large, the fish counted were mostly bass, yellow bass and bluegills. Seining 5 sites would take these able volunteers until noon to accomplish. They count fish better than they count money (Remember the door prizes at the banquet?).

Bob, Walter and David rode in the electrofishing boat and their first task was to set up two gill nets, one across open water 7 ft. deep on the north side of the peninsula, the other across water that was 18 ft. deep out from Centennial's property. The purpose of the gill net was to confirm the types and numbers of open water, moving, pelagic fish (fish that tend to stay around the middle of the water column at its deepest point). Common pelagic fish are white bass, yellow bass, gizzard shad, gar and carp. These fish tend to move around a lot and sometimes do not turn up in electrofishing.

After an hour, the nets were checked and found to be loaded with carp, gar, large 10 in. gizzard, a crappie, a sand bass and a catfish mixed in to boot. It took another hour to empty the nets after which Bob Lusk pronounced that he had seen what he need to see. We have large carp and large gizzard shad. We don't seem to have small carp or small gizzard shad, a clue to what has been happening in the lake.

The rest of the day was spent electrofishing with everyone in the boat rigged to produce 240-300 volts of potential to move 7-10 amps of current in an area about 20 ft. in diameter and about 6 ft. deep. Marty and Paul were in the front of the boat to dip up the stunned fish. David was in the middle of the boat to empty the fish from the dip nets into the livewell. Bob and Walter were in the back controlling the boat and working the electrofish equipment.

One bass was shocked up with a bluegill's head sticking out of his mouth. The blugill must have just been swallowed when the electrodes made Mr. Bass gag. Mr. Bass coughed up this confused bluegill into the livewell where it was counted and released in pretty beat up shape. That is one fish with a story to tell.

Bob Lusk checked the stomach contents of another bass and found a yellow bass and crawfish inside. He did this by poking two fingers down the bass' gullet and gently squeezing its belly with his other hand. Out popped a yellow bass. That black bass left the boat glad to be alive but cheated out of a meal.

Tom Root (The Club Gypsy and Gadfly) arrived on the scene in the afternoon and followed us around. Occasionally we would miss netting a bass or carp we had shocked up. Tom would just move in behind, scoop them up and bring them to us. Some mischievous spirit made him think in would be a neat prank to put one of those carp into Ben Thomas's half submerged sailboat when we passed by. Remind you of Grumpy Old Men?

By 5 PM we had caught, weighed, measured and recorded 100 largemouth bass. A public lake usually yields about 15 bass per hour. We were shocking up from 20-25 bass per hour which was a good rate according to Mr. Lusk. Most were native bass, but we appear to have a strong presence of the Florida bass strain in the lake. Many fish had pure Florida-like markings (mottled patterns above the lateral line, 3 warpaint like stripes on the head). A whole lot of bass had Florida hybrid markings prompting Mr. Lusk to remark that we probably did not need to buy any more Florida bass for the sake of introducing them here. They are here and in good numbers. Many bass were injured and scarred with commorant (water turkey) inflicted wounds. There was no sympathy in the boat for these federally protected birds.

We shocked up over 100 carp and gar with such ease that it became clear to us that this was THE way to control undesirable fish populations. Some of us are seriously considering the feasibility of building a electrofishing boat to be used as a lake management tool. All shocked fish were counted. Here are some comments on the other species we saw.

GHOST MINNOWS (Silversides): Visually observed these in good numbers in the reeds along the banks.

BLUEGILL: WE did not see enough bluegill. The bluegill we found were mostly native bluegill in a 5-7 inch range. It takes a bass over 15 inches to feed on bluegill this size. Bluegill are really important in the scheme of things, first because they are a favorite bank hugging food source for bass, and second, they are a favorite gamefish for youngsters too impatient for bass fishing.

CRAPPIE: The crappie had not yet moved out of the deep waters so we only caught four whites all day. However, we do know that they are there in good numbers.

YELLOW BASS: These exist in great numbers. Although they prey on the smaller forage fish which we need, the yellow bass are small enough to be suitable forage for most of the bass. In fact, one bass had a yellow bass in its stomach to prove it. Most of us do not care for the yellow bass and consider them a nuisance. Evidently they are serving a useful function of feeding the bass.

THREADFIN SHAD: We saw thousands of threadfin shad. Threadfin shad are the smaller yellow tailed shad. They are only 1-3 inches in length and live about 2 years. The presence of threadfin shad is good since they are a size that can be eaten by most of the predator fish.

GIZZARD SHAD: We have TOO MANY large, 10" plus gizzard shad.Gizzard shad grow large and live about 8 years. The gill nets filled up with them. We did not find any small gizzard shad. Mr. Lusk says that when you find only large fish in a species, it means that there has been an overpopulation of this species. When this happens they begin releasing a pheromone which shuts down reproduction. What does this mean? It takes a 20" bass or larger to be able to eat a shad this size. Therefore our biggest bass have plenty to eat, but we don't have many of those. Most of our smaller bass have to duke it out for the less abundant smaller forage. These abundant large gizzard need to be thinned in numbers so that they will begin reproducing again, making SMALLER gizzard shad available to most of the rest of our bass. Large gizard shad are very prolific when they do reproduce. One 10" gizzard shad can release over 200,000 eggs.

CARP: In 1905,carp were introduced into the US by none other than Teddy Rooseelt. They were brought from Germany as a means to control certain kinds of moss. Now they are everywhere in the country. We must have shocked up over 100 of them since this is the time of year for them to be in shallow water. These were large 8-20 lb. carp, no small carp. What does this mean? Again, large carp have overpopulated the lake and they live forever without a predator. Although they go through the motions, they are not reproducing. We need to reduce their numbers for two reasons. First, so that they will begin reproducing again and provide smaller carp into the food chain for bass to eat. Second, the spot they occupy in the food chain could be occupied by another more desirable gamefish, like channel catfish.

PARASITES: Bob Lusk pointed out several parasites which are normal for our waters. First there were the small leeches that can be found in the mouths of some bass. Then there was a translucent worm with an anchor shaped head imbedded in the side of one bass. This is called an anchor worm. Some bass had small round yellow spots imbedded in the base of their tail fins. These are called yellow grub worms and its host is a snail. When these get to be a problem you can stock Redear sunfish which feed on the host snails.

GOOD ENVIRONMENT NEWS: Two Rainbow Darters were found. These are the small 2-4 inch long bottom hugging fish that end up in our minnow traps under our docks. They cannot survive in waters or mud with even the slightest toxicity. A translucent microscopic shrimp called grass shrimp were found on the north side of the peninsula. They also are very sensitive to toxins. Large, old gizzard shad, which we have an over abundance of, are also very sensitive to toxins in the water. These all indicate that our mud and waters are environmentally stable and mostly toxin free. If we ever see large gizzard shad or the darters dying, this would be a red flag.

Mr. Lusk plotted the weights and measurements of the 100 bass on a graph. The resulting curve was compared to standard weight and measurement data. Then he tallied the numbers of bass in specific length categories.

Main Observations and Conclusions

1) All bass except those over 20" are underweight compared to standard.

2) Most of our bass fall into the 11-15 inch range. This is where growth stops since their numbers are too great for suitable forage available.

The 11-15 in. bass population should be thinned in numbers. The forage suitable to this size bass should be increased. This is the bottleneck. A smaller number of these bass need to eat more, get fatter and grow to approach 20" where they can tap into the large gizzard shad that are abundantly available.

Data Collected

# inches weight
1 4 0
2 6 0.13
3 6 0.06
4 6 0.06
5 6 0.06
6 6 0.06
7 6 0
8 7 0.13
9 7 0.13
10 7.3 0.25
11 7.5 0
12 7.8 0.13
13 8 0.19
14 8 0.19
15 8.3 0.19
16 8.5 0.19
17 8.5 0.19
18 9 0.38
19 9 0.19
20 10 0.25
21 10.5 0.5
22 10.8 0.44
23 10.8 0.44
24 10.8 0.38
25 11 0.44
26 11.3 0.63
27 11.5 0.69
28 11.5 0.56
29 11.5 0.56
30 11.8 0.94
31 11.8 0.63
32 11.8 0.63
33 12 0.69
34 12 0.69
35 12 0.69
36 12 0.69
37 12 0.69
38 12.3 0.75
39 12.3 0.75
40 12.5 0.88
41 12.5 0.81
42 12.5 0.75
43 12.5 0.75
44 12.5 0.75
45 12.5 0.75
46 12.5 0.69
47 12.8 0.88
48 12.8 0.81
49 13 0.94
50 13 0.88
51 13 0.81
52 13.3 0.81
53 13.5 1.13
54 13.5 1
55 13.5 1
56 13.5 0.94
57 14 1.38
58 14 1.13
59 14 1.13
60 14 1.06
61 14 1.06
62 14 1
63 14 1
64 14 0.94
65 14.3 1.31
66 14.3 1.25
67 14.3 1.13
68 14.5 1.44
69 14.5 1.25
70 15 1.44
71 15 1.44
72 15 1.38
73 15 1.38
74 15 1.25
75 15 1.19
76 15 1.19
77 15 1.19
78 15.5 1.63
79 15.5 1.5
80 15.5 1.38
81 16 1.75
82 16 1.69
83 16 1.56
84 16.3 1.81
85 16.5 1.88
86 17 2.5
87 17 2.19
88 17 1.88
89 17.3 2.25
90 17.5 2.56
91 18.5 3
92 18.5 2.63
93 19 3.69
94 19 3.38
95 19 3.19
96 19 4.19
97 19.5 3.69
98 19.5 3.56
99 21 5.44
100 21 5.13

Recommendations

1) HARVEST BASS IN THE 11 TO 15 INCH SLOT. That also means release bass over 15 inches, and release bass under 11 inches (these can be eaten by larger bass). As much as 25 lbs per year per lake acre can be selectively harvested.

2) REMOVE CARP AND LARGE GIZZARD SHAD. To the extent this is possible, fewer large carp and large gizzard shad may start them reproducing again making small gizzard shad and small carp available to the pool of suitable bass forage. We might consider building an electrofish boat in order to accomplish this. Large gizzard shad might be traded for bluegill.

3) STOCK 4-5 INCH COPPERNOSE BLUEGILL. This increases the best bass bank hugging forage and improves fishing for the kids around the lake. Cost for 5,000 would be around $.40 each in the spring

4) INCREASE WATER FERTILITY. Adding fertilizer ($500 worth) to the lake will increase phytoplankton at the bottom end of the food chain. A visibility of 18-24 is desirable

5) FEED THE FISH. Homeowners might begin feeding fish off of their docks. A commercial floating fish food would work

6) CONTINUE OUR FISH LOGGING AND DATA COLLECTION. Monitor results and adjust management strategy as needed.


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