Overview Pros and Cons of MMH Status of Six T & E Fish Species in Northern Illinois Lakes EA 2009 Incidental lh Harvest tc Catch of fth Those Species

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1 Mechanical Macrophyte Harvesting, What s the Catch? Ken Cummings EA Engineering, Science, and Technology Deerfield, Illinois SE NALMS Conference May 2012 Columbus, GA

2 Overview Pros and Cons of MMH Status of Six T & E Fish Species in Northern Illinois Lakes EA 2009 Incidental lh Harvest tc Catch of fth Those Species Summary/Conclusions: What Have We Learned? How to Minimize Adverse Effects of Regular Harvesting

3 Harvesting - 101

4 Pros of MMH Pros and Cons Results in immediate open areas Efficient i and can be targeted t Can improve fish habitat and fishing success No chemicals needed Macrophytes remain intact creating habitat Removes plant biomass and can reduce sedimentation rate

5 Cons of MMH Pros and Cons (cont.) Resuspends sediments Removes critters (macroinverts, frogs, turtles, fish, etc.) Non-selective, short-term term solution Expensive up to $900/acre for a private contractor up to $115K/harvester, plus maintenance

6 EA 2009 Study Objectives Determine status & incidental harvest catch of six T & E fish species in three northeast IL lakes:» Pugnose shiner (Notropis anogenus)-e» Blacknose shiner (N. heterolepis)-e» Blackchin shiner (N. heterodon)-t)» Banded killifish (Fundulus diaphanus)-t» Northern starhead topminnow (F. dispar)-tt» Iowa darter (Etheostoma exile)-t

7 Study Locations West and East Loon Lakes Bangs Lake

8 Study Locations (cont.) Three Well Vegetated Glacial Lakes in Lake County, IL Max. Depth Dominant Lake Size (acres) (ft) Macrophyte East Loon* EWM West Loon EWM Bangs EWM * Illinois Natural Areas Inventory y( (INAI) Site Advanced Identification (ADID) Wetland

9 Threatened and Endangered Species Distribution Target species found primarily in northern states. All six T&E spp. collected historically from NE IL, including Loon Lake. Some species are locally abundant in lakes in northeast IL. Page and Burr 2011 Page and Burr 2011 Lyons 2011

10 T & E Species (cont.) Life History & Habitat All six target species prefer clear, calm, moderately vegetated waters. Spawning varies, but generally occurs between April and early August.

11 Methods Study conducted in July of 2009 Non-intensive Study Seining Conducted at five to seven locations within each lake to determine status of target sp.

12 Methods (cont.) Seining (cont.) Two to six hauls were conducted at each location using a 30 ft bag or a 10 ft. straight seine Relative abundance determined for non-target species whereas target species were counted.

13 Methods (cont.) Harvesting Hrs. of Harvesting/Lake (4-14 runs) Representative of Typical Harvesting Practices Typically in 3-6 6ftW Water Depth All Aquatic Macrophytes Collected were Examined

14 Results - Loon Lake Combined, 16 species were collected by seining and harvesting in East and West Loon Lakes: Seining Only Harvester Only Both Methods C. Mudminnow Iowa darter Grass pickerel Blacknose shiner Blackchin shiner Bluntnose minnow Banded killifish Lake chubsucker Green sunfish Pumpkinseed Golden shiner Warmouth Bluegill Largemouth bass Black crappie Yellow perch Total Sp

15 Loon Lake Seining Results Status of Target Species Seining yielded three of the six listed species. Numbers Collected Species West Loon East Loon Total Blacknose shiner Blackchin shiner Banded killifish Total

16 Target Species Loon Lake Harvester Results Iowa darter was the only listed species collected harvesting in Two specimens were collected at harvester run # 4 in WLL. Seining at Locs. 1 & 2 = 44 blackchin shiners YET 3 harvester runs (22 min; >850m of shoreline) = 0 blackchin shiners

17 Loon Lake Harvester Results (cont.) All Species: Raw Numbers & % Abundance Species West Loon East Loon Lakes Combined # % # % # % Bluegill LM bass Warmouth Y. Perch Iowa darter <1 G. pickerel 1 <1 1 <1 2 <1 Blk. Crappie <1 Golden shiner <1 Total Species 6 5 8

18 Harvester Catch Rates (#/hour) for the Dominant Fish and All Fish Combined- Loon Lake No. of Indiv viduals/hou ur W. Loon E. Loon Bluegill LM bass Warmouth Y. Perch Total

19 Harvester Catch Rates (#/40 hours) for the Dominant Fish Collected in Loon Lake 12.0 (1,000s) No. of In ndividuals/4 40 Hours ( Bluegill LM bass Warmouth Y. Perch W. Loon E. Loon

20 Results - Bangs Lake 16 species were collected by seining and harvesting in Bangs Lake: Seining Only Harvester Only Both Methods G. Pickerel* Lake chubsucker* Yellow bullhead* Blackchin shiner Golden shiner Pumpkinseed Iowa darter* Bluegill Blacknose shiner Johnny darter Largemouth bass Bluntnose minnow Least darter* Spotfin shiner Yellow perch Banded killifish* Total Sp * represented by only one or two individuals

21 Bangs Lake Seining Results Status of Target Species Seining yielded three of the six listed species: Species Total Blacknose shiner 19 Blackchin shiner 41 Banded killifish 3 Total 63 Most (52 %) were collected at Location 2, which yielded 8 of 19 blacknose shiners and 25 of 41 blackchin shiners.

22 Bangs Lake Harvester Results All Species: Raw Numbers (56 min) and Percent Abundance Species # % Bluegill LM bass 7 8 Blackchin shiner 5 6 Yellow bullhead 1 1 Iowa darter 1 1 Total Again, Few T&E Fish Collected Harvesting Compared to Seining

23 Harvester Catch Rates (#/hour) for the Dominant Fish and All Fish Combined- Bangs and Loon Lakes uals/hour No o. of Individ W. Loon E. Loon Bangs Lake Bluegill LM bass Total 7

24 Summary/Conclusions Diverse, Healthy Fish Communities in all Lakes 30 to 50 % of All Species Encountered were Collected by Harvesting Two of Six Listed Species (i.e., Iowa Darter and Blackchin Shiner) Collected Harvesting, but Low Numbers Iowa Darter Only Listed Species Collected Exclusively by Harvesting Bluegill & Largemouth Bass Dominated the Harvest Catch in all Lakes Harvester Avoidance of Some Listed Species Likely Based on Catch Data and Field Observations Harvesting Practices May Affect Catch Rates

25 Summary/Conclusions (cont.) Some T & E species (others) are susceptible to harvesting, BUT additional studies will be required to evaluate which is creating more of an impact.

26 Limiting Negative Effects of Harvesting Know When and Where Species of Concern Spawn and Limit Harvesting During Peak Spawning Periods Limit Harvesting in Densely Populated Areas or Areas of Preferred Habitat Incorporate Least Impact Harvesting Practices Know What s in Your Lake and Where!

27 Acknowledgements SE NALMS Loon Lakes Management Assoc. Village of Wauconda EA Colleagues: Mike Kacinski & Ashton Schardt Lake County Health Dept. References Madsen, J. D Advantages and disadvantages of aquatic plant management techniques. North American Lake Management Society; from LakeLine, v. 20, no.1, pp Gettys, L. A., W. Haller, and M Bellaud. Biology and control of aquatic plants-a a best management practices handbook Aquatic Ecosystem Restoration Foundation, Marietta, Georgia

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