Introduction: JadEco, LLC PO BOX 445 Shannon, IL 61078

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1 Introduction: was contacted to collected data on the fishery for Lake Holiday. AC Electroshocking was conducted at 2 locations on September 28, Fish population data was collected for a total of 100 minutes utilizing AC electrofishing equipment. 549 fish were collected with 14 species being represented. 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. Summary of Fisheries Data: Over all, the collection indicated a decent fishery at Lake Holiday for anglers. For those game species collected, the relative weight and PSD s indicated a healthy population of sport fish, however, the catch per unit effort (CPUE) for bass and bluegill were under the desired objectives. The overall CPUE for all fish collected was under the objective of 6 fish per minute. Over 47% of the fish collected were from nongame species and indicates a large biomass of nongame fish in Lake Holiday. These nongame species consisted primarily of carp, green sunfish, and yellow bass. When isolated from the rest of the collection, desirable sport species CPUE represented less than 3 fish per minute with a total of 288 fish collected. The desired range is over 6 fish per minute. Lake Holiday has a limited carrying capacity of fish for the lake. It can only support a specific biomass of fish. This can be represented by desirable species such as bass and bluegill or nongame species. Carp, green sunfish, and yellow bass represent much of the biomass at Lake Holiday. Along with the competition for space, carp, green sunfish, and yellow bass directly compete with other desirable sport fish for food. By reducing their biomass, or converting them to a desirable species (stocking of predators that can and will eat these nongame fish), you can improve the angling experience on the lake. Along with taking up space or biomass, carp continually turn up the lake sediments releasing nutrients, prey on game fish nests (eggs), and prevent beneficial aquatic plants from establishing. As you are aware, by removing them, you can have a positive impact on the lake ecology as well as the fishery. The current carp removal efforts, once successful, should have a big impact on the sport fish population at Lake Holiday.

2 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 (12 ) 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 40 to 70. The PSD for largemouth bass collected at Lake Holiday is within the objective range at 47. Along with this, the RSD14 value (the proportion of fish greater than 14 inches divided by the number of fish greater than 8 inches) was at 27. A desired RSD14 range for Largemouth bass is 10 to 20. This indicates a good portion of the bass collected were at the 14 or greater size. We collected largemouth bass from 3 to almost 17 during the survey, with an average size of only 5.5. In proportion to the rest of the bass collected, we had a very high collection rate of young of the year bass ranging in size from 3 6 and this collection represented 76% of the entire bass catch (hence the 5.5 average size). Only 16 largemouth bass were collected over 8 in length. The catch per unit effort (CPUE) on largemouth (.67 fish/minute) was under the targeted range of fish/minute. The average relative weights (Wr) for largemouth bass fell within the objective range at 95 (Range 90110). This would indicate that the fishermen are usually seeing relatively fat, healthy bass during angling outings. The average weight of largemouth over 12 was at 1.6 pounds, which appear to be consistent with the tournament totals that we reviewed. Bluegill: The CPUE for bluegill was at 1.54 fish per minute, which is under the objective range (24.5 fish/minute). Bluegills ranging from 1.2 to almost 8 were collected with the average size at 3.1. The PSD for bluegill at Lake Holiday was at 31, and falls within objective ranges between 20 and 60. The RSD7 values for bluegill (the number of fish larger than 7 divided by the number of fish 3 and larger) is at 21 and is over the desirable range of 5 to 20. Nearly 70% of the bluegill collected were young of the year fish. The average relative weight for bluegill was at 97 (desirable range between 90 and 110). Crappie: While electrofishing is not the ideal sampling method for crappie, we collected both black and white crappie during the survey. In general, this would indicate a decent population of crappie present. The average size crappie was over 8 ½ in length and was over 1/3 of a pound. The relative weight for both black and white crappie was nearly 100, indicating a population of fat and healthy crappie at Lake Holiday.

3 With both black and white crappie were represented in the sample, the black crappie were dominant. This can cycle back and forth between black and white crappie, but normally the black crappie dominate in populations were both are present. The upcoming crappie fishing at Lake Holiday should be very good. We did not collect multiple year classes, however. Other Species: Other sport fish species present included walleye, channel catfish, white bass, smallmouth bass, and red ear sunfish. Along with these, nondesirable green sunfish were very abundant during this survey. The green sunfish collection represented 34% of the total collection. The average relative weight for green sunfish was over 101, indicating the health and condition of the green sunfish is very high and plenty of forage available to them. The average size of green sunfish was over 4 with the range from 2 to over 7 ½ in length. While green sunfish are native to Illinois, they are considered a nondesirable species within sport fish populations. 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 15 fish daily limit on green sunfish. Green sunfish should be a catch and remove species 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. If this is the case, the Association should work towards education of the community on species identification. The smallmouth bass ranged from 3 to nearly 15. If smallmouth bass were not stocked within the last couple of years, this would indicate successful spawning and recruitment of smallmouth bass is occurring. The smaller fish in the sample indicate successful spawning occurred at Lake Holiday this year as well as over winter survival of last year spawn. The channel catfish population appears to being doing very well at Lake Holiday. With the low numbers of largemouth present in our sample, this isn t a surprise. Heavy bass populations can suppress recruitment of channel catfish through predation, and this doesn t appear to be happening at Lake Holiday. Catfish ranged from 12 up to 27 and nearly 9 pounds. The average length of the collection was over 17. The catfish average relative weight was very good at 107. A heavy population of large channel catfish such as at Lake Holiday is probably feeding heavily on a fish diet as well. Current creel limits have no restrictions on size or limit, and should not change. While no flathead catfish were collected, one fish was seen but unable to be netted.

4 A total of 8 yellow bass were collected ranging in size from 3 ½ to nearly 8 in length. This would indicate a successfully reproducing population of yellow bass at Lake Holiday. Yellow bass are considered a nondesirable species for Lake Holiday. They, too, are in competition for limited space and food that is needed by your sport fish population. Any yellow bass caught should not be released back into the lake. Recommendations: Creel Limits: The association should begin and educational program for their members on proper fish identification. We can discuss educational opportunities at your request. At this time, white bass and yellow bass are present. Bluegill, red ear, and green sunfish are all present. Smallmouth and largemouth bass are both present. Channel catfish and flathead catfish are both present. With these species all being present, the membership should know how to identify them, and the association can do this through news articles with color pictures and creel limit signs with color pictures and easy identification characteristics. Continue catch and release on the largemouth bass and smallmouth bass fisheries. Change the limit on green sunfish to be open, and not protected under the bluegill limits. 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. At this time, Lake Holiday has much species diversity with 10 of the 14 species being predators: Largemouth and smallmouth bass, walleye, white bass, yellow bass, black and white crappie, flathead catfish, channel catfish, and yellow perch. All of which are competing for food and space against one another at one stage of life or another. The data collection indicates a good number of bass spawning occurred in 2015, but further surveys will determine over winter survival as well as recruitment for those able to evade predation. This seems to hold consistent with the bluegill as well. Further, and possibly more extensive, data collection may be needed to fully understand this fishery. Habitat Enhancement: 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

5 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. I can assist you with this design and concepts if needed. To my knowledge, the Association is working towards establishing native aquatic plants in the lake. This effort will be greatly improved once the carp population is reduced, and the water clarity improved. During the limited time electrofishing in this survey, we were able to collect over 350 pounds of carp, with a CPUE (.59) over double the accepted collection rate of.25. We are aware the association is making a concerted effort towards carp removal using a commercial fisherman and other options using telemetry and targeted netting. Other opportunities would be carp fishing tournaments or bow fishing tournaments as well as educational efforts to the community to remove carp when caught, and do not release them back into the lake. 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, you should monitor for invasive nonnative 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. At the time of the survey, the community was experiencing a planktonic algae bloom that appeared to be dominated by bluegreen algae. Bluegreen 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. Stocking: 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 hatcheryraised walleye. If walleye are a highly sought after species for Lake Holiday anglers, they will need to be stocked periodically to continue catching walleye. If stocking does not occur, walleye fishing will drop dramatically once the age structure changes towards older, larger than 16 fish that

6 are kept in the creel limits or die of disease, spillway escapement, or old age. With the current trends, a limited stocking of walleye would be recommended, with a focus on trying to balance the bass and bluegill populations. Once again, there is competition for food and space amongst these predators. At this time, stocking rates should not exceed 10 per acre if walleye are stocked. Stocking of largemouth bass can be done, however, hatchery bass are not as well adapted to survival as naturally spawned largemouth bass that have grown on the local forage base and adapted to available cover. The current stocking program by the fishing club consists of minnow rearing largemouth bass in the hatchery pond, and then releasing them. These fish may have a better chance of survival, as they are able to grow to a larger size, and evade many of the predators in the lake until fall. To our knowledge, the hatchery rearing pond was used to raise walleye in the past, and it is currently used for largemouth bass. If the leadership determines walleye to be a desired species, and stocking performed, the pond could be used alternately to stock walleye one year, and largemouth bass the following until the largemouth bass population is within objective ranges for catch per unit effort. 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. No other predator stocking, such as muskie, should occur at this time. Muskie are a supplemental species used to reduce some of the over population of bluegill, or to convert gizzard shad biomass (when present) to another sport species. In the absence of gizzard shad, studies have shown that muskie will target bluegill as a primary forage base. At this time, our bluegill catch per unit effort is below our target objective, and does not need added pressure. Gizzard shad were not collected in this survey, and likely are not present in the lake. Gizzard shad are not a desirable species for Lake Holiday.

7 Figure 1: Sampling Locations Table 1: Catch Per Unit Effort (CPUE) by species Species: Number Fish/Minute Objective (fish/min) Largemouth Bass: Bluegill: Black /White Crappie: Smallmouth Bass: Walleye: Channel catfish: Carp: Below 0.25 Yellow Perch: Yellow bass: White bass: Redear sunfish: Green sunfish: Golden shiner: Total CPUE plus *Gamefish CPUE only: Phone: JadEco, LLC PO BOX 445 Shannon, IL jrush@jadecoconsulting.com

8 Table 2: Proportional Stock Density (PSD) Species: PSD Objective Largemouth Bass: Bluegill: Black Crappie: White Crappie: Table 3: Relative Weight (Wr) Species: Wr (Ave) Range Objective Largemouth bass: Bluegill: Black / White crappie: Walleye: Smallmouth bass: Channel catfish Carp: Green sunfish: Table 4: Length Ranges by Species Species: Length: Average Largemouth Bass: Smallmouth Bass: Bluegill: Black /White Crappie: Walleye: Yellow perch: White Bass: Carp: Redear: Channel Catfish: Green Sunfish: Yellow Bass:

9 Frequency at age (largemouth bass) Frequency at Age Frequency at age (bluegill) Frequency at Age