JadEco, LLC PO BOX 445 Shannon, IL 61078

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1 Introduction: With the assistance of Lake Holiday staff and volunteers, we were able to conduct an AC electrofishing survey on May 8, 27. Water temperatures were 2.3 C (8.5 F) and water clarity was decent at 29. Fish collection was performed at various areas around the lake, including previously sampled areas during past surveys. Fish population data was collected for a total of 5 minutes utilizing AC electrofishing equipment. Fourteen species were represented with,3 fish collected. Of those, 5 species were either undesirable or non-game species. As in previous surveys, data analysis consisted of catch per unit effort per species and total catch per unit effort. This provides information on the fish population density, and potential trends in the fishery. PSD s (proportional stock density) were also calculated on important game species to assist with understanding the size structure within the lake. The last metric analyzed was the relative weight (Wr). This metric provides information on length to weight relationships to better understand if your game fish are relatively fat, or relatively thin and potential changes in the predator / prey relationships and available forage. This information was then compared to previous surveys. Summary of Fisheries Data: The main comparisons made in this report are between spring 2 and spring 27 data. Seasonal variability may be observed when comparing various seasonal data. As with previous reports, there are several graphs at the end of this report comparing the multiple surveys across years and seasons. Overall catch per unit effort for spring surveys increased from 9. fish per minute in 2 to.5 fish per minute in spring 27. There was a large increase in CPUE for desirable species from.78 fish per minute in 2 to 8.9 fish per minute in 27. The objective overall CPUE is or more fish per minute and our collection was at.5 per minute. Undesirable species made up less than 29% of the catch rate during the spring survey. Previously, 3 of the catch rate (fall 2), 5 (fall 25), and (spring 2) were undesirable species. The trend has been an increase in collection of game species and a reduction in undesirable species. Largemouth bass and bluegill relative weights continue to show good condition for the bass and bluegill collected. The proportional stock density indicates an improvement in both the largemouth bass size distribution (more larger fish), and the bluegill size distribution. Both were above their objective ranges. Overall, the collection indicated an improving bass and bluegill fishery. Yellow bass were present again this spring, representing nearly 9% of the overall collection. These catch rates, size ranges, and average size have remained consistent year to year with spring surveys thus far. Phone: PO BOX 5 Shannon, IL 78

2 Common carp comprised.% of the total collection this spring in comparison to last spring, % during fall 25, and 3.% fall 2. This is the lowest carp collection we have observed through electrofishing. However, carp were collected at small sizes again this spring, indicating spawning and recruitment is occurring. As you are aware, along with taking up space or biomass, carp continually turn up the lake sediments releasing nutrients and negatively impacting aquatic plant growth, prey on game fish nests (eggs), and prevent beneficial aquatic plants from establishing. By removing carp, you can have a positive impact on the lake ecology as well as the fishery. The current carp removal efforts appear to be having an impact on the carp numbers. This effort should continue, especially since smaller carp are still being captured. Largemouth Bass: When evaluating the size structure of the fish population, we utilize a metric known as proportional stock density or PSD. This metric analyzes the size structure within the population. The proportion of fish greater than quality size (2 ) divided by the number of fish greater than stock size (8 ) provides the PSD value. A desired PSD range for largemouth bass is a value from to 7. The PSD for largemouth bass collected at Lake Holiday was above our objective range at 78 during the spring 27 survey. This is consistent with the previous spring survey at 79. Along with this, the RSD value (the proportion of fish greater than inches divided by the number of fish greater than 8 inches) was up from spring 2 () at 57. Spring PSD and RSD values have consistently been higher than the fall values. RSD5 and RSD were at 8 and 22 respectively for spring 27 (up from 33 and 8 the previous spring. The proportion of bass collected in the plus sizes in relation to stock size (8 and larger) has continually increased since 25, when comparing seasons. During fall 25, we observed RSD values at 7. Subsequent fall sampling provided values of 9. Spring 2 values were at 8, and 27 spring values were at 22. These numbers indicate that the proportion of largemouth bass inches or larger have trended upward since 25. Last fall our CPUE for largemouth bass was within our objective range with.2 fish per minute collected. The spring 27 survey was below our objective at.73 fish per minute, however, it was up from the spring 2 (.5) survey. Of those bass collected, sizes ranged from 3. to 8.7 during the survey, with an average size of 9.7. The bass collected under the 8 stock size comprised of the overall largemouth bass catch. It is possible multiple year-classes are represented under 8, but without age and growth studies, we can t be certain. Phone: PO BOX 5 Shannon, IL 78

3 The spring 27 average relative weights (Wr) for largemouth bass were very good at 99 and were within the objective range (9-). Relative weights ranged from 7 to 2 this spring. The average Wr was down slightly from the 2 spring survey (2). A Wr of 99 would indicate that the fishermen should continue seeing relatively fat, healthy bass during angling outings. During previous surveys, there was a low collection of largemouth bass between the to 7 inch sizes in both the fall 25 (%) and spring 2 (2) surveys. These sizes were better represented during the fall 2 survey with 3% of the collection comprised of bass between and 7 inches, and could be an indication of better spawning / recruitment. This higher percentage was observed again spring 27 with 3% of the bass collected were represented between and 7 in length, indicating good over winter survival and recruitment for the younger bass. This trend should be monitored during future surveys. These younger year classes should recruit into the larger sizes the next few years. This would help control the bluegill population as well as carp and other undesirable species. This should also increase our CPUE for bass in future surveys. Bluegill: The CPUE for bluegill collected spring 27 was.8 fish per minute, and was above our objective range of 2 to.5 fish / minute. This, however, was lower than the spring 2 collection at 9. fish per minute where we subsampled the bluegill population due to the high collection rate. Bluegills ranging from.9 to 8.3 with an average size of 5. collected. Average size was up from spring 2 of.8. The PSD for bluegill was at during this survey. This was above our objective range of 2-, and was up from spring 2 at 3. There was a high proportion of bluegill over the 7 length. The RSD7 values for bluegill (the number of fish larger than 7 divided by the number of fish 3 and larger) were at 29. Up from spring 2 (). Twenty-four percent of the bluegill collected were less than in length. Fifty-five percent of the bluegill collected were over. This would indicate some very good bluegill fishing for larger fish. The average relative weight for bluegill was at 93 with a range from 9-7 (desirable range between 9 and ). This was down from the 2 spring survey (99). Continue tracking bluegill relative weights and PSD data to better understand the bluegill size distribution. Future increases in creel limits may be warranted to balance the bluegill population. Crappie: The 27 spring sample provided data on crappie that were collected. While sizes ranged from 5.2 to 9.9 in length, the average was 8.8. Both black and white crappie were present in the survey. Recall from previous reports that electrofishing Phone: PO BOX 5 Shannon, IL 78

4 is not the ideal sampling method for crappie. However, we collected crappie at a rate of.9 fish per minute, which is excellent for electrofishing. This is up from the previous spring survey at.2 fish per minute. The average relative weight for both black and white crappie was at 9 for spring 27, which is down slightly from spring 2 at 9, and is at the lower end of the objective range. Both black and white crappie were represented in the sample, and once again the white crappie dominated the collection. As stated in previous surveys, crappie dominance can shift back and forth, but normally the black crappie dominate in populations were both are present. This is not the case for Lake Holiday at this time. Multiple size classes were represented in the spring 27 survey and the upcoming crappie fishing at Lake Holiday should be good. Other Species: Other sport fish species present during the spring 27 survey included channel catfish (), smallmouth bass (), and flathead catfish (). Undesirable, or nongame species present were common carp, yellow bass, white suckers, golden shiners, yellow bullhead, and green sunfish. Green Sunfish: Undesirable green sunfish were less abundant during this survey, compared to the spring 2 survey. Green sunfish were collected at a rate of 2.5 fish per minute in spring 2 and.9 fish per minute in spring 27. Green sunfish comprised less than 8% of the entire catch during this sample, where last spring they represented over 2 of the total collection. While green sunfish are native to Illinois, they are considered undesirable, or nondesirable species within sport fish populations. Consistent with the previous report, their large mouth allows them to compete with larger fish for prey and they eat eggs and young of other desirable species. Studies have shown them to be heavy predators on other fish species. Current creel limits include a 5 fish daily limit on sunfish. Anglers should be allowed to keep all green sunfish as opposed to being protected through creel limits. I anticipate this is in place due to the concern for misidentification of bluegill as a green sunfish. If this is the case, the Association should work towards education of the community on species identification. Even with allowing harvest, the numbers will be hard to control without predator pressure. I anticipate increased bass numbers will assist with reducing the green sunfish population. Smallmouth Bass: Smallmouth bass were collected at a rate of.5 fish per minute with fish collected. The smallmouth bass ranged from 8. to 3.9, with an average size of.5. The average condition of the smallmouth bass collected was low with relative Phone: PO BOX 5 Shannon, IL 78

5 weights at 89, down slightly from last spring and the Wr ranged between 8 and 3. Average relative weights for smallmouth bass have been higher at Lake Holiday during spring samples. Channel Catfish: Channel catfish were collected at a rate of. fish per minute with total fish collected. This is up slightly from the spring 2 survey at.35 fish per minute. Catfish ranged from. up to 2.. The average length of the catfish collected was.. The catfish average relative weight was within objective range, but was at the lower spectrum at 9. This is down from the previous spring survey at 98. Current creel limits have no restrictions on size or limit, and should not change. Flathead Catfish: During the spring 2 survey we collected one flathead catfish at 2.8 in length. The spring 2 survey provided data on 3 individual fish ranging in size from.9 to 23.5 with an average of 8.3. Yellow Bass: We collected yellow bass at a rate of 2.5 fish per minute with a total of 25 fish collected. The sizes ranged from.8 to with an average of 8.. This is consistent with the survey from spring 2. As discussed in previous reports, the spring collection rate is significantly higher than the fall and this is most likely due to the pelagic behavior of the yellow bass, being more off-shore. Yellow bass are considered a non-desirable species for Lake Holiday. They, too, are in competition for limited space and food that is needed by your sport fish population. The Association should encourage anglers to keep yellow bass and not release them back into the lake. This larger average size may help entice anglers to harvest them for table fare. You should continue to have fun angling events for yellow bass, such as your winter ice fishing events. Common Carp (rough fish): Along with the common carp collected, we also observed mirror carp. Our carp collection rates were much lower than previous collections with only 2 carp collected for a rate of.8 fish per minute. This rate falls within our objective of.25 fish per minute or less. Our collection last spring was at.5 fish per minute with a total of 73 fish collected. Sizes of carp collected this spring ranged from with an average size of The weights ranged from. lb to over 9.5 lbs with an average weight of 9 lbs. As stated in previous reports, continuing your efforts to remove carp is important to improving the gamefish fishery. We continually collect smaller carp (2.5 in this Phone: PO BOX 5 Shannon, IL 78

6 survey), and this indicates the carp are continuing to recruit into the fishery. Carp removal will be a continual effort for Lake Holiday. Recommendations: Creel Limits: Creel limit recommendations continue to remain as previously suggested: - Continue catch and release on the largemouth bass and smallmouth bass fisheries. - Keep the limit on green sunfish open, and not protected under the bluegill limits. Anglers should be able to decipher between bluegill and green sunfish through your educational program. - Place yellow bass as catch and remove species. - Place carp as a catch and remove species. - Current catfish creel limits have no restrictions on size or limit, and should not change. Please keep me updated on what is being done with the creel limits. Habitat Enhancement: As stated in the previous surveys, one of the most important things that can improve the bass fishery is improving habitat for young of the year survival and ambush for larger bass hunting grounds. The less energy a largemouth bass has to use to catch forage, and the bigger the forage base (or food packet ) the more the bass can put into growth and less energy into hunting. Strategic placement of quality structure throughout the lake will improve the fishery. With this being a multi use lake for more than fishing (ie swimming, boating, skiing), care should be taken to ensure any structures placed are placed safely for these multi uses. Many fishing clubs do collections for Christmas trees in the winter to be placed with concrete blocks. While these are a good effort, small structures like this are not going to greatly impact the fishery as a whole. Also, they break down quickly and can add nutrients to the lake that we do not want. Placement of larger cribs, and large hardwood brush are the best options. Other artificial materials that do not add nutrients can also be used to build fish structures for both shallow and deep water. Again, I can assist you with this design and concepts if needed. Please keep us updated with any work that is performed. This will help to better understand the fishery, and changes, as we move forward. The establishment of a quality native plant community would provide food and cover as well as water quality benefits to the lake and members. As plants establish, Phone: PO BOX 5 Shannon, IL 78

7 you should monitor for invasive non-native species and develop a lake management plan including aquatic plant management goals, objectives, and control. While native plants are beneficial to the lake, they have a tendency to grow in areas where they may be considered a nuisance (for example, around swim areas and boat docks). The association should develop a management program and educate the members on this program, as well as the need for quality native aquatic plants. During previous fall surveys, we have observed a planktonic algae bloom that appeared to be dominated by blue-green algae. Blue-green algae are known to have the capability of producing toxins that can be harmful to humans and animals. Native aquatic plants can help balance the use of nutrients, such as phosphorus and nitrogen, which would otherwise be available only to the planktonic algae. No bloom was observed in the spring 2 or spring 27 survey. Stocking: Largemouth bass: Our overall CPUE was still lower than our objective range of -2.5 fish per minute, but size ranges appear to be better represented again in spring 27. Forty-five percent of the bass collected were under 8 in length. It appears we are observing better recruitment and over winter survival in recent surveys and this trend needs to be monitored. The fall 27 survey will provide better insight. Refer back to the section on habitat enhancement. The best thing you can do for the bass fishery is to enhance the habitat available for these fish for young of the year nurseries as well as ambush structures that help them forage more efficiently. Habitat enhancement should help provide the needed cover to improve the recruitment to stock size, above 8. In turn, this would improve the catch per unit effort in time. Walleye: It is unlikely that the walleye are spawning in Lake Holiday, and in the past the fishery has been supplemented through a stocking program by the local club and possibly by purchasing hatchery-raised walleye. If walleye are a highly sought after species for Lake Holiday anglers, they will need to be stocked periodically to continue catching walleye. As stated in previous reports, if stocking does not occur, walleye fishing could drop dramatically once the age structure changes towards older, larger than fish that are kept in the creel limits or die of disease, spillway escapement, or old age. Stocking 5 walleye per acre at -9 would be recommended to maintain a year class for the walleye fishery. We recommend no more than walleye per acre stocked annually. Phone: PO BOX 5 Shannon, IL 78

8 The fall 2 report requested the volunteers collect netting data on walleye collected for the hatchery operation and the data forwarded on for review. If data was collected, please provide the information to JadEco for review of the walleye fishery. With all stocking options recommended, if budgetary constraints are a problem, stocking every other year may be an option, keeping in mind limited year-class strength and size gaps in the fish that may be observed by fisherman and their creel. Further review of water quality parameters such as temperature and dissolved oxygen profiles would help to better understand available habitat to the walleye throughout the year. Angler creel surveys would also provide data on if the stocked walleye are surviving. Monitoring the fishery through consistent data collection will be important to understand how the fishery is changing and what will be required in the future. Please keep us updated with current stocking programs and records to help us monitor trends in the fishery. Phone: PO BOX 5 Shannon, IL 78

9 Figure : Sampling Locations Table : Catch Per Unit Effort (CPUE) by species Species: Number Fish/Minute s* 7s* s* 7s* Largemouth Bass: Bluegill: 577** Black /White Crappie: Smallmouth Bass:.7.5 Walleye:..3 Channel catfish: Flathead catfish: 3.2. Carp: White sucker: Yellow Perch: n/a. n/a Yellow bass: White bass: n/a. n/a Redear sunfish: n/a n/a n/a n/a Green sunfish: 8** Yellow Bullhead: n/a n/a.3 Golden shiner: Total CPUE Gamefish CPUE only: *s = Spring 2 sample *7s = Spring 27 sample **Bluegill and Green sunfish subsampled at min. Obj. (fish/min) Below.25. plus Phone: JadEco, LLC PO BOX 5 Shannon, IL 78 jrush@jadecoconsulting.com

10 Table 2: Proportional Stock Density (PSD) Species: PSD Objective 7s* s* Largemouth Bass: Bluegill: 3 2- *7s = Spring 27 sample *s= Spring 2 sample Table 3: Relative Weight (Wr) Species: Wr (Ave) Range Objective s* 7s* s* 7s* Largemouth bass: Bluegill: Black / White crappie: Walleye: Smallmouth bass: Channel catfish *s = Spring 2 sample *7s = Spring 27 sample Table : Length Ranges by Species Species: Length: Average s* 7s* s* 7s* Largemouth Bass: Smallmouth Bass: Bluegill: Black /White Crappie: Walleye: Yellow perch: 5.5 n/a 5.5 n/a White Bass:.9 n/a.9 n/a Carp: Redear: Channel Catfish: Green Sunfish: Yellow Bass: Flathead Catfish: Golden Shiner: Yellow Bullhead: n/a 8. n/a 8. White Sucker *s = Spring 2 sample *7s = Spring 27 sample Phone: PO BOX 5 Shannon, IL 78

11 Bluegill Population Distribution Greater Than Stock Size - Spring Only 39% 3% % % 3% 2 % Spring 27 Spring Bluegill Number Collected > Stock Size 25 Number Collected Spring 27 Spring Phone: PO BOX 5 Shannon, IL 78

12 Bluegill Population Distribution > Stock Size % 3% 3% 39% 3% % 3% 3% 33% 2 % Fall 2 Spring 2 Fall 27 Spring Bluegill Number Collected > Stock Size Number Collected Fall 2 Spring 2 Fall 27 Spring Phone: PO BOX 5 Shannon, IL 78

13 Largemouth Bass Population Distribution > Stock Size % 2 9% 3% 9% 3% 9% 3% 9% 3% 3% 3% 3% 3% 3% 3% Spring 2 Spring 27 Largemouth Bass Number Collected > Stock Size 2 2 Number Colleted Spring 2 Spring 27 Phone: PO BOX 5 Shannon, IL 78

14 Largemouth Bass Population Distribution > Stock Size % 2 2 3% % 2 3% 3% 3% 3% % 3% 3% 9% 9% 9% 9% 3% 3% 3% 3% % 3% Fall Spring 2 Fall 2 Spring 27 Largemouth Bass Number Collected > Stock Size Number Colleted Fall Spring 2 Fall 2 Spring 27 Phone: PO BOX 5 Shannon, IL 78

15 Bluegill Population - Spring Only %.8% 3.3%.% 9.3% 5.3% 3.% 2.8%.% 28.3%.%.9%...% Spring 27 Spring % Bluegill Population 3.% % %.9%. 7.8%.% 9..8% % 9.3% 5.3%.% 2.8% 3.9% 3.9% %..% 8.% 28.3%....%...% Fall 2 Spring 2 Fall 27 Spring Phone: PO BOX 5 Shannon, IL 78

16 Largemouth Bass Population - Spring Only % 2 9% % % % % % % 8% % % % % % % Spring 2 Spring 27 Largemouth Bass Population 3 3 % Fall 25 Spring 2 Fall 2 Spring 27 Phone: PO BOX 5 Shannon, IL 78

17 Bluegill Frequency at Estimated Age % % 5.% %. % 8.%.. Estimated Age Class by Length Group 2 Spring 27 Spring Bluegill Frequency at Estimated Age 3.% % 7.% 2.% 29% 5.%.3%. %. 5.8%.9% % 3. 2.% 2.% 8.%.... Estimated Age Class by Length Group 25 Fall 2 Fall 2 Spring 27 Spring Phone: PO BOX 5 Shannon, IL 78

18 Largemouth Bass Frequency at Estimated Age % % %. 8..9% 2. 3.% Estimated Age Class by Length Group 2 Spring 27 Spring % Largemouth Bass Frequency at Estimated Age 3.3% %. 3.3%. 8.3%..% 8....% % 3.3%.. 3.3% 8..9% % Estimated Age Class by Length Group 25 Fall 2 Fall 2 Spring 27 Spring Phone: PO BOX 5 Shannon, IL 78

19 Carp Collected -Comparison Spring Only 3 25 Number Collected Spring 27 Spring Carp Collected -Comparison Fall/Spring 3 25 Number Collected Fall 2 Spring 2 Fall 27 Spring Phone: PO BOX 5 Shannon, IL 78

20 Crappie (Black and White) Population % %. 2.9% % 3.8% 2.3%. 32.% 53.8% Fall 2 Spring 2 Fall 27 Spring Crappie (Black and White) - Number Collected 5 8 Number Collected Fall 2 Spring 2 Fall 27 Spring Phone: PO BOX 5 Shannon, IL 78