Fisheries Management Plan

Fisheries Management Plan 2005-2014 Lake Mary, Douglas County Dow ID #: 21-092 1

Fisheries Management Plan Region Area DOW# County Lake Class Acreage NW Glenwood F116 21-092 Douglas Mary 27 SA 2,371 LA 1,020 Quick Reference Survey and Stocking Schedule Year Inventory Walleye Stocking Special Assessment Other 2005 Community Assessment WAE: Fall YOY 2006 Fry*-2,040,000 WAE: Fall YOY 2007 WAE: Popn Assmt Fall YOY 2008 Fry*-2,040,000 WAE: Fall YOY 2009 Resurvey WAE: Fall YOY 2010 Fry*-2,040,000 WAE: Fall YOY 2011 WAE: Popn Assmt Fall YOY 2012 Fry*-2,040,000 WAE: Fall YOY Creel Survey** 2013 Community Assessment WAE: Fall YOY 2014 Fry*-2,040,000 WAE: Fall YOY Plan Redraft * Fry will be stocked in alternate years. Dependent upon fall electrofishing catches of YOY walleye, fingerlings may also be stocked in any given year. (Please refer to stocking plan in Direct Fish Management section) ** Creel scheduling is dependent upon funding and staffing 2

NA-01570-01 Fisheries Management Plan Region Area DOW# County Lake Class Acreage NW Glenwood F116 21-092 Douglas Mary 27 SA 2,371 LA 1,020 DNR Mission Statement: Our mission is to work with citizens to conserve and manage the state's natural resources, to provide outdoor recreation opportunities, and to provide for commercial uses of natural resources in a way that creates a sustainable quality of life. Introduction and Plan Purpose The DNR Division of Fish and Wildlife manages, protects, and regulates Minnesota s fish and wildlife resources. The Section of Fisheries is responsible for managing and sustaining the diverse fisheries in Minnesota's 5,400 game fish lakes and 15,000 miles of streams and rivers. Scope and complexity of fishery management issues, funding and administrative constraints, and mandates for efficacy and accountability necessitate a planned, systematic approach to fisheries management programming. Area Fisheries professionals prepare fisheries plans for most, if not all, fishable lakes and streams with public access and active fish management allocations. Lake-specific fisheries management plans serve as a delivery mechanism for applying the DNR mission, goals, and strategic programming to field operations. The plans serve as the basis of annual work plans and operating budget development. The lake-specific fisheries management plans also ensure directed, systematic application of management programs and activities, which in turn facilitates program evaluation and accountability. Written fisheries management plans ensure continuity in service delivery and afford customers, local units of government, and other land and natural resource management entities with an over-view of fisheries resource and habitat conditions, as well as an understanding of the actual or potential influence of land use activities on water quality and fisheries sustainability. Lastly, plan development provides a critical avenue for public input and involvement into resource issues, management strategies, and program integration. Fisheries management plans are crafted to address key performance areas and reflect natural resource management principles established in the Department s Strategic Conservation Agenda 2003-2007. Those guidelines include: Enhance communication and working relationships with core natural resource constituents; give particular attention to hunters and anglers Cooperate with other agencies, local units of government, citizens, and stakeholders to effectively manage and sustain natural resources Provide for sustainable economic use of our natural resources Make resource and land-use decisions at the local level 3

Integrate planning and budgeting across area, regional, and state organizational levels Adapt the DNR organizational structure to more effectively and efficiently deliver services Use sound scientific principles, accurate information, and state-of-the-art technology in managing natural resources Model the sustainable use of natural resources in our work 4

Narrative Ecosystem Trends or Concerns Principle fish management concerns relate to habitat instability and degradation. Water clarity has declined steadily for at least 15 year (Attachment 1). Average summer Secchi measurements have varied as much as 4.0 ft. Summer water clarity averaged less than 5.0 ft in 2000 and 2003. Lake Mary is relatively shallow in comparison to other large lakes in Douglas County. Approximately half of the surface area is less than 15.0 feet in depth. Water level has been dynamic, fluctuating more than 3.0 ft within a year (Attachment 2). Divergence in habitat conditions is evident in fish community shifts and recruitment variability. Northern pike and to a lesser extent, walleye, benefited from periods of high water. Changing predator abundance and size distribution stimulates compensatory shifts throughout the gamefish community. The end results of habitat instability include variable gamefish catches and age distribution among surveys. Significant fish community shifts can be projected to accrue with sustained degradation of water quality. Fish survey statistics depict some modest community changes, but certainty of data interpretation is undermined by inter-basin fish movements and noise introduced by climatic instability. Existence and sustained presence of tullibee within the Lake Mary fish community is surprising given the basin s eutrophic state and shallowness. This coldwater fish species will likely be lost with increasing eutrophy. Despite indications of an increasingly unsuitable habitat, tullibee persist. There is suspicion that these fish may be seasonal migrants from connected basins such as Lake Andrew. Yellow bullhead are most abundant in lakes with good water quality. Black bullhead abundance can be expected to increase rapidly with degradation of water quality. The relative capture ratio of yellow and black bullhead during surveys may serve as a sensitive indicator of increasing eutrophy (Schupp and Wilson 1993). Yellow bullhead captures from Lake Mary greatly exceeded that of black bullhead in early surveys through 1993. Total bullhead catches during recent surveys has diminished. Black bullhead catches increased to exceed that of yellow bullhead in the 2001 survey. Gillnet catches of common carp in 2005 were the highest recorded since 1982. This population expansion may be a combined result of water quality degradation and a June 2003 flood event during the peak of the common carp spawning period. Lastly, bluegill sunfish catches have declined over time. The increased relative percentage of adult fish tends to suggest recruitment of young bluegill has diminished. Causative factors could include loss of vegetated habitat, water level instability during nesting periods, or greater exploitation by predators. Observations of undesired habitat and fish community changes should not be extrapolated to suggest Lake Mary s fishery is facing collapse. There is reason for concern, but survey statistics and interpretations should not be extrapolated to suggest the lake s fishery is poor or in a state of collapse. Lake Mary continues to support excellent and diverse fishing opportunities. It remains among the most productive lakes within the Glenwood Management Area. Species-specific gamefish narratives 5

follow. Summary survey statistics and state of the population in respect to management objectives are described in Attachment 3. 6

Gamefish Population Assessments Walleye: Walleye remain abundant. Gillnet captures in 2005, averaged 13.5 walleye/net. Gillnet CPUE has varied from 10.0-23.3 fish/net among surveys dating back to 1982. For reference, the interquartile range of expected walleye catches for Lake Class 27 basins is 3.3 8.8 fish/gillnet. Population abundance is sustained through natural recruitment and supplemental stockings. Fall electrofishing surveys have been conducted annually since 1992 in order to estimate numbers of young-of-year walleye and thus, future year class strength (Attachment 4). Surveys are completed in advance of fingerling stockings to afford segregation of contributions from natural reproduction and fry stockings from that of fingerling stockings. Electrofishing statistics and age distribution of gillnet captures document that some variable level of natural recruitment occurs most years. Strong natural year class established in 1999 contributed to elevated catches of walleye captured in the 2001 survey. With awareness that contributions from natural recruitment or fry stockings cannot be differentiated, age structure of survey catches provides clear evidence that year class strength is greater in those years fry are stocked. Annual recruitment rate from alternate year fry stockings is more variable than that of annual fingerling stocking, but performance of fry stockings has outpaced contributions of fingerlings. Success of biannual fry stocking and natural recruitment variability pose some interesting fishery management challenges. Growth rate is density-dependent. In response to good, near consecutive age groups established in 1996, 1998, 1999, and 2000, a four-year-old walleye captured in the 2001 survey averaged 15.1 inches in total length. At a lesser density and biannual spike in recruitment, walleye captured during the 2005 survey averaged 16.9 inches in total length at age-4. Recruitment variability or unpredictability and density-dependent growth impacts confound fit and potential function of harvest management strategies. Size structure of 2001 and 2005 populations is near optimal to reasonably balance demands of consumptive and quality fishing interests. PSD is at or above 50. Forty-eight percent of stocksize captures were within the range of 15.0 20.0 inches in length. Nine percent of stock-size captures exceeded 20.0 inches. Three memorable-size walleye (> 25.0 inches) were recorded in 2005 catches. Northern pike abundance and age distribution have great influence on fish community dynamics, overall productivity, and walleye recruitment. Climatic variability appears to dictate pike recruitment and population abundance. Pike catches swelled to a high of 14.1 fish/gillnet in 1987 in apparent response to heavy precipitation and high water levels from 1985 1987. Population abundance dropped sharply with onset of an extended drought period from 1988 1991. Pike catches have been highly variable during the past four surveys. Gillnet CPUE was 11.5 pike/net in 2001, but only 2.5 pike/net in 2005. Age and size distribution reflect recruitment variability between surveys. PSD among capture samples has ranged from 10 to 44. Age and growth statistics from recent survey catches proved contrary to expectations. Average growth of pike caught during the 2001 survey was faster than that of pike making up the 2005 population sample even though abundance indicators were much 7

higher. Older individuals in the 2005 catch averaged only 25.6 inches in total length at age-7. Differential growth among surveys may be attributable to prey availability. Yellow perch catches in 2005 were low. Northern pike have a comparatively short longevity. Age distribution of recent survey catches has been truncated at age-7. In response to slowing growth and high natural mortality rate, few preferred-size (> 28.0 ) pike have been recorded during the last five surveys. RSD-P has not exceeded 4. Anglers will be encouraged to increase exploitation of small pike. There are not likely to grow much larger and greater harvest may result in better walleye recruitment. Black crappie: Crappie can support a significant portion of total annual fishing pressure and harvest. Annual recruitment variability tends to define annual yields and fishing quality. Similarly, age and size distributions of survey catches are shaped by survey timing in relationship to preceding year class strength. Despite variability in recruitment, average trapnet catches have remained within the interquartile range of normal for Lake Class 27. Graphic representations of trapnet catches among surveys suggest contributions from periodic good year classes may not be as great through the 90s. Crappie growth is typically above average. Given opportunity to grow, crappie can attain memorable-size (12.0 inches and larger) at or near age-6. Thirty-nine percent of black crappie captures during the 2001 survey exceeded 10.0 inches in length. Harvest regulation may have potential to improve and sustain a more consistent fishery. However, crappie fishing potential will be minimized to maximize walleye densities. Angler exploitation can be very heavy with recruitment of a strong year class to the fishery. Pressure is greatest during early spring and winter months. Periods of concentrated harvest have stimulated requests for restrictive harvest regulation. The Lake Mary Association forwarded a request to stock crappie to remedy harvest pressures. Based on modest population abundance, irregular recruitment, and acceptable growth, a reduced daily bag or minimum length limit may have potential to sustain harvest over a longer period of time. Given boom or bust fishery characteristics, non-compliance rate can be projected to be high when those periodic strong year classes growth to harvestable size. Largemouth bass: Electrofishing catches have varied from 24.7 86.7 largemouth bass/hour among surveys. Catches during the 2005 daytime survey averaged 44.6 fish/hour. Based on age distribution of captures, dissimilar catches can largely be attributed to annual recruitment variability. Additional noise may be induced by divergence in total sampling effort among surveys. Catch statistics tend to describe a moderate population density of medium-size bass. PSD of electrofishing captures averages 61. The relative percentage of 15.0-inch and larger bass has ranged from 6 27, dependent upon age structure. Growth is near normal. Older captures averaged 15.0 inches in total length at age-7. Captures of preferred-size and larger bass in the 2005 survey was lower than anticipated. Lower than expected RSD-P in 2005 would appear to be related to poor recruitment in 1995-1997. No eight-, nine-, or 10-year-old bass were captured. Bluegill: Survey statistics since 1982 depict a long-term decline in population abundance. While a net decline in population density is desirable to improving growth and fishing quality, expressed as average size caught, a sustained decline is indicative of less suitable habitat conditions or significant shifts in fish community structure. Gamefish community shifts included reduced northern pike abundance, a modest increase in yellow perch standing stock, 8

irregular largemouth bass recruitment, and potentially a net decrease in crappie recruitment. None of these community shifts would seem significant enough to suppress a very prolific population such as bluegill. Lower population abundance may be a function of habitat changes induced by water quality degradation or climatic instability. From a positive perspective, growth rate has improved. Older individuals in the 2005 population sample exceeded the management objective of 7.0 inches in total length by age-6. The relative percentage of preferred-size (> 8.0 in.) does not reflect faster growth. Only five of 2005 captures exceeded 8.0 inches in total length. Anglers likely exert sufficient exploitation of larger bluegill to suppress potential size distribution. Limiting Factors Water clarity is declining. Causative factors are uncertain, but fisheries impacts are becoming evident and there is no doubt of ramifications of sustained degradation. Fish community diversity will lessen. Submergent vegetation will become increasingly limited. Population abundance of gamefishes reliant upon vegetative habitat and sight-feeders such as largemouth bass and northern pike can be projected to decline. Walleye recruitment may increase. Undervalued fishes such as common carp and black bullhead will come to dominate total fish biomass. Occasional winterkill has been noted to occur in Little Mary during extended snow coverage and low water level. Excessive fishing pressure may be limiting size and age distribution of bluegill, black crappie, and walleye. Natural and induced changes in water level may have negatively impacted certain fish populations. Empirical observations depict a negative correlation between northern pike recruitment and low water level. Quality of recreational fishing experiences is periodically impaired by wind, water level, access shallowness, and increasingly, competing water sports. Resort accommodations have lessened with conversion of resorts to shared community developments allowing permanent or seasonal placement of RV s. Social Considerations Lake Mary is a popular fishing destination for area residents and tourists. Total angling effort averaged 89,170 hours (92.9 hours/ha) in 1986, 1987, 1988, and 1991. Angling effort was lower in 1989 and 1990 (66.9 hrs/ha) when low water levels rendered the north public access unusable. Forty-two percent of total angling pressure was directed towards walleye. The Lake Mary Sportsmen's Club was very active in fish management issues, especially walleye stocking and roughfish removal. This entity evolved into the Lake Mary Association, which remains active in lake and fisheries management issues. Key fisheries interests include walleye and black crappie stocking, harvest management, habitat protection, and common carp control. The Lake Mary Association worked diligently to mitigate an ill-suited planned unit development on the west shoreline. Through cooperative efforts, an 800 ft common dock was denied and the 9

decision was upheld in court of law due to poor site suitability. The group challenged land application of sewage sludge from the Alexandria Lakes Area Sanitary District. The Association was instrumental acquisition of the Lake Mary AMA. Primary concerns have come to focus on declining water quality and low water level. The Douglas County Ditch Inspector was challenged for cleaning or opening up ditches draining to Lake Mary. The Association championed extension of ALASR sewer service around the lake. Multiple requests to increase lake level have been forwarded through the Division of Waters. A six-inch plate was added to the sill of the carp trap to accommodate an increase. Water level manipulation proved derisive among Lake Association membership. The Lake Mary Association sustains a standing request to increase lake level another six inches, but would like to increase depth by 18 inches. Working relationships have been stressed at times based on issues, perspectives, and leadership changes. Adversarial interactions revolved around walleye stocking methodology and water level manipulation. The Association or some members were displeased with the Section of Fisheries reluctance to support an additional water level increase due to concerns of emergent vegetation losses and structural inadequacy of the carp trap to hold further head. Recent Association initiatives have focused on degradation of water quality and need to control or remove common carp. They have sought reconstruction of the east Lake Mary trap and collective operation of the outlet trap. Some are frustrated by reluctance of the Section of Fisheries to enjoin in this effort. An estimated 75% of anglers interviewed during six years of creel research in the 80 s, were patrons of a resort. Ten resorts were in operation at that time. This group of business owners formed a Resort Association. Opportunities for non-local anglers to stay and fish from a traditional fishing resort are becoming increasingly scarce. The traditional fishing resort is quickly being transformed into RV cooperatives or timeshares due to high shoreland property values and taxes. The Douglas County Board of Adjustment has heard three proposals to convert existing resorts on Lake Mary into such cooperatives where RV or mobile home owners will have opportunity to purchase the footprint of their existing campsites. This action greatly increases residential density, docking sites, and potential profits for the sellers. Some Lake Association members have expressed opposition to these resort conversions. ALASD sewer lines have now been extended around the perimeter of Mary and Andrews Lakes. Presence of sewer hook-ups will likely serve as a growth engine to stimulate further development around the lake. Extensive commercial development continues on the south side of Alexandria. It is reasonable to project associated and significant residential development south and west of current city limits within the confines of Latoka, Andrew, and Mary lakes watersheds. There is imminent need to review and as needed, revised County land use ordinances to minimize impacts to water quality. Lake Mary is very exposed to wind and wave fetch. Even modest southerly winds can impair recreational boating and fishing experiences on the main lake. Anglers and recreational boaters tend to concentrate into Little Mary to escape wind and waves. Concentrated surface water uses 10

in this small portion of the lake undermine enjoyment and safety of anglers at anchor. Surface water zoning may become increasingly necessary to accommodate recreational demands. Integrated Management Opportunities Key threats to diverse, sustainable fishing are degrading water quality and resultant habitat changes. Lake Mary was specifically identified in redraft of the Douglas County Comprehensive Local Water Plan as a special concern and priority action item because of the basin s sustained decline in water quality. Water quality deterioration proves inconsistent with expectations of extension of central sewer service around the lake and elimination of septic discharges to the lake. There is need to better understand nutrient loading and sources to stem accelerated eutrophication. Remedial initiatives must include Lake Mary Township officials; Douglas County governmental departments to include Lake and Resource Management, Ditch Authority, and SWCD; the Lake Mary Association; ALASR; MPCA; and DNR Divisions of Waters and Fish & Wildlife. Collaborative efforts should be initiated promptly. Fisheries Management Programming Long-term management expenditures have been relatively traditional in scope. Programming focus has broadened with recognition and need to prevent non-sustainable degradation of water quality and sensitive fisheries habitats. Program activities and various achievements from previous plans include: Well documented gamefish stocking records date back to 1945. Historical records indicate stockings were occurring as early as 1915. Early stockings included all primary cool- and warm-water gamefishes. Supplemental walleye stockings have been sustained. Various spawning areas were posted to No Fishing beginning in 1944. This practice was discontinued with documentation of limited use and lack of species-specific needs for protection. State and contract roughfish control efforts were initiated in the winter of 1956-57. Periodic ( 18 of 34 years) removal efforts were conducted through 1990. Common carp and bullhead comprised the greatest total biomass of roughfishes harvested. An estimated 421,300 lbs of common carp and 225,400 lbs of bullhead were harvested during time frame. The greatest carp harvest occurred in early 1965. Over 116,000 lbs or 50 lbs/surface acre was removed. Total annual yields over 18 years of effort averaged 9.8 lbs of carp and 5.2 lbs of bullhead per surface acre. An initial standardized fisheries survey was completed in 1955. Thirteen fish community or specialized fisheries research assessments have followed. Annual fall electrofishing assessments have been sustained since 1992 in order to evaluate and project the relative year class strength of young walleye stemming from natural reproduction or fry stocking. Cooperative ventures have also included completion of a radio-telemetry study to locate important walleye spawning areas and acquisition of the South Lake Mary AMA. Faced with evidence of sustained, undesirable changes in water quality and habitat attributes, traditional management programming should be considered secondary to watershed management initiatives directed at reducing pollutant loading and restoring water quality. Causes of recent water clarity declines are not overtly evident. Section of Fisheries financial allocations and 11

authority to influence land use decisions or changes is limited, but energies must be directed into collaborative efforts to inventory land uses, identify pollutant sources, and address causes. Inventory and planning should be initiated and completed prior to large-scale development within the watershed. Important in-lake habitat attributes should be recognized and preserved from degradation or infestation of harmful exotic aquatics. Shoreline restoration or retrofit measures should be promoted. Fisheries management programming should also include initiatives to enhance fishing quality, address seasonal over-exploitation, and ensure safe, enjoyable fishing experiences. Inventory Water quality monitoring should be expanded to collect water from natural and structural inlets to document runoff volumes and pollutant loadings in order to prioritize remedial actions. The GIS lakeshed database layer should be fully complemented with other critical watershed information such as landuse, soils, ownership, drainages, ditches, etc. to better visualize and model changes in water flow, nutrient loading, and other impacts of development and landuse changes. A pictorial history of the lake would be useful in visually portraying cumulative habitat changes such as loss of emergent vegetation. Recreational use, fishing pressure, and harvest information may greatly aid in regulatory decision-making and management investments on the lake. Work load permitting, it may prove useful to conduct specialized netting assessments. Such assessments would greatly enhance the information available in formulating any decisions to implement restrictive harvest regulations. Fall electrofishing surveys should be sustained indefinitely to measure natural recruitment of walleye, determine success of fry stockings, or justify fingerling stockings. References Heiskary, S. A. and C. B. Wilson. 1989. The regional nature of lake water quality across Minnesota: an analysis for improving resource management. Journal of the Minnesota Academy of Science 55(1): 71-77. Schupp, D. and B. Wilson. 1993. Developing lake goals for water quality and fisheries. Lake Line, December Issue. Wendlandt, J. 1998. Location of preferred walleye spawning habitat in Lake Mary as determine by radio telemetry. Minnesota Department of Natural Resources, Division of Fisheries Study IV Report, Job 427, Sportfish Restoration Act Project F-29-R(P)-18, Study 566. 12

Management Goals Protect Lake Mary and its aquatic resources from human-induced degradation in order to maintain a thriving community of native gamefishes. Influence fish community structure and biomass to maintain optimal harvestable yields of walleye without inordinate repercussions on other gamefish populations and fishing diversity. Sustain, and as possible, enhance angling experiences and recreational opportunities. 13

چ Management Objectives Desired Water Quality & Habitat Attributes Water quality indices characteristic of lakes within the upper 75th percentile distribution for the North Central Hardwood Forest ecoregion (Heiskary and Wilson 1989), i.e. - Mean summer, Secchi transparency greater than 2.2 meters (7.2 ft), - Summer, epilimnetic total phosphorous conc. < 35 ug/l, - Chlorophyll a concentrations < 15 ug/l over 80% of the summer Continued absence of aquatic exotics not already naturalized within the lake Rooted aquatic macrophyte growth to a depth of 15 feet and a 25% reduction in number or littoral area impacted through aquatic plant management permitting Critical walleye spawning habitat identified and protected from degradation. Preservation or cooperative restoration of at least 5.0% (3,100 ft) feet of shoreland habitat Desired Social, Economic & Aesthetic Attributes A recreational suitability classification of fully supporting swimmable and fishable uses. Continued appreciation of lakeshore property values High quality fishing experiences with primary emphasis on sustaining a consumptive walleye fishery. Sustain an open water harvest of all gamefish species in excess of 13.0 lbs/acre, with an average catch rate of 1.0 fish/hour. Continued presence and vitality of fishing resorts operating in a traditional format. Desired Gamefish Population/Fish Community Attributes Sustained presence and proliferation of northern cisco (tullibee) and rock bass Consistent, sustained natural recruitment of walleye Best appropriate fish community structure to optimize energy flow, growth, and harvestable yields of walleye without non-sustainable impacts to other gamefish populations and fishing diversity. 14

Species-specific Subgoals for Gamefishes Walleye: Sustain optimal yields of harvestable-sized fish. Desired population objectives for abundance, size distribution, growth, and fishing success are: - Gillnet catch rate near 15 fish per net night - PSD and RSD-P values of 50 and 15, respectively - Growth rate of 14.5 inches at age 3 - Average walleye catch rate of 0.15 fish/hour Northern pike: Act on opportunities to minimize annual recruitment and increase angling mortality to sustain a lower population density, minimize biomass of competing predators, and maintain above average densities of young-of-year and yearling yellow perch. Optimal population statistics would reflect: - Gillnet catch rate of 5 or less - PSD of 50 or greater with at least 10% of the stock-size captures greater than 28.0 inches - Minimal growth rate of 21.0 inches at age-4 Yellow perch: Sustain appropriate densities of YOY and age-1 prey to optimize walleye growth and provide some modest fishing opportunity. Desired population characteristics my reflect: - Average gillnet catch rate of 20 or more fish/net - PSD within the range of 10-20 Bluegill: Sustain a relatively low-density population of fast growing fish to support a consumptive fishery and minimize bluegill and yellow perch interactions. Optimal population statistics may reflect: - Average trapnet catches within the range of 10-15 fish/net - PSD within the range of 50-70 - Growth rate 7.0 inches or greater by age-6 Largemouth bass: Sustain a high quality fishery described as medium densities 15.0-inch and larger bass. Desired population characteristics include: - Population densities yielding an electrofishing catch rate within the range of 40 60 fish/hour - PSD of 60 or greater with 20% of stock-size fish in capture samples exceeding 15.0 inches - Growth rate of 15.0 inches (preferred-size) at or before age-6 Black crappie: More accurately describe population structure and community dynamics. In light of primary management emphasis on walleye and difficulty sampling this population, management objectives will reflect historical averages, i.e. - Mean summer trapnet catches of 1.2 or more fish/net - 20% of stock-sized individuals in capture samples at or exceeding 10.0 inches - Growth of 10.0 inches at age-5 15

Operational Plan Habitat Management A. Seek support of shoreline residents in adopting a no net loss policy of emergent aquatic macrophytes, particularly hardstem bulrush. As opportunities arise, assist property owners interested in developing shoreline buffer strips and restoring aquatic plants via the Douglas County Lakescaping Project. B. Monitor watershed or shoreline developmental proposals submitted through the Douglas County Board of Planning and Adjustment permit review process, and as warranted, promptly initiate action or provide recommendations to ensure that environmental concerns and aquatic resource issues are appropriately addressed. C. Step up environmental review coordination among the Lake Mary Township officers, Lake Mary Association, SWCD, Land and Resource Management, and DNR to broaden and enhance environmental review process and coordination, unify messages forwarded to decision-makers, and enhance political clout in effectively protecting the lake from inappropriate land use. D. Monitor and react to DOW/APM permit requests to minimize or prevent detrimental environmental damages. Conduct follow-up investigations of every third DOW or APM permit issued to assess compliance with permitting terms. E. Ensure sensitive habitat or landscape features within the shoreland management zone are accurately described and assertively recognize those features and protection strategies in land use permitting. F. Periodically re-assess the existing condition and potential use of gamefish spawning areas, and if appropriate, identify enhancement options to tributary flowages from the north (Sunset Bay) and from Lake Andrew. Assess spawning use and egg deposition in relationship to water level. G. Identify eroding shoreline and encourage actions to correct and stabilize such areas. H. Monitor tributaries or ditch channels and as necessary address seasonal barriers to walleye spawning movements. I. Champion listing Lake Mary on the MPCA Impaired Waters listing to generate attention and allocation of resources to watershed management or water quality improvement initiatives. J. Work with Technical Support Services and Division of Waters to lay groundwork for sustained requests and administrative support to raise the water level of Lake Mary. Preliminary work should include structural assessments of the physical integrity and capacity of the trap infrastructure to support greater head pressures if additional plating is attached to the trap. Discussions should also address outlet modifications should the roughfish trap be removed in lieu of a low head outlet structure. Fishing & Trip Satisfaction Enhancements A. Encourage acquisition or relocation of the north access to a site with deeper water. B. Promote use or extension of the DATA snowmobile trail system to facilitate walking or biking along the east shoreline. Such enhancements should be considered in advance of residential development. C. Work with the Lake Mary Association, Douglas County Water Patrol, and Trails and Waterways to mark boulders posing navigation hazards between Little Mary and the main 16

basin. D. Promote adoption of a slow-no visible wake surface water ordinance within Little Mary Lake to address safety concerns, optimize fishing experiences, and reduce potential silt resuspension and algal blooms in the shallow sub-basin. E. Act on opportunities to promote and sustain fishing resort accommodations. Direct Fish Management A. Act on opportunities to manage northern pike reproduction and recruitment. Options may include periodic restrictions to preferred spawning habitat. B. Further refine walleye stocking to increase stocking efficacy, sustain management objectives, and reasonably satisfy the consumptive demand placed on this fishery. The stocking plan include: Continue walleye fry stockings in alternate years (2006, 2008, 2010, etc) at a rate of 2,000 fry/littoral acre (2,040,000 fry). All stocked fish should be chemically marked to allow for differentiation of stocked fish from natural recruits. Fall electrofishing assessments will continue on an annual basis. Based on assumptions that young-of-year walleye catches reflect actual density of young walleye and probable recruitment, the mean of young-of-year catch statistics from all previous surveys will be utilized as a trigger value to program additional contingency stockings. The grand mean of average catch rates calculated from the last 15 surveys is near 50 YOY walleye/hour of electrofishing effort. Should fall, electrofishing yields fall below the trigger value in two consecutive electrofishing surveys, fingerlings will be stocked at a rate up to 1.0 lb/littoral acre (1,020 lbs) immediately following the second annual electrofishing survey. C. Maintain the West Lake Mary roughfish trap structure and barrier panels in operable condition pending necessity of a last line of defense against Asian carp or other exotic gamefish immigration into Mary, Pocket, and Andrew lakes. Dependent upon Association volunteer support to operate the trap and minimial kill of gamefishes, issue Class B permits and provide materials to roughfish removal operations. Harvest Management A. Evaluate probable biological responses and angler support for pursuing harvest regulations that have the greatest potential to optimize fishing quality and fish community structure. Species of interest would likely include walleye and black crappie. Walleye harvest management would have to be flexible in order to properly respond to recruitment variability and density-dependent growth impacts. B. Promote harvest of small northern pike and release of some portion of large pike to enhance fishing quality and increase total annual mortality of young pike. C. Work with the Lake Mary Resort Association to co-develop and implement a "catch and release" educational promotion and/or a resort-based fishing contest designed to promote the lake s diversified angling opportunities, i.e. Lake Mary Summer Safari. D. Seek funding to conduct a year round creel survey to be incorporated in conjunction with standardized netting surveys. 17

Inventory, Evaluation, & Planning A. Take advantage of Water Plan action items to enjoin a collaborative of local government officials, resource management staff, and citizenry to promptly enjoin and develop monitoring strategies and a guiding water quality improvement plan. B. Sustain standardized netting assessments every four years. Fish community assessments will be programmed for 2005 and 2013. A lake resurvey will be scheduled for 2009. C. Dependent upon updated information needs, indications of a problem occurrence, recruitment uncertainties, complement standard survey timing with special walleye population assessments every two years, i.e. 2007 and 2011. D. As seasonal workloads permit, supplement standardized netting with special spring or fall trapnetting assessments to better evaluate the black crappie population. E. Identify important northern pike spawning areas and assess potential and feasibility to structurally manage access to preferred habitat during the spawning period. F. Acquire the upper Long Prairie River lakeshed database from the Division of Waters and cooperatively expand database layers to include land use, drainage, existing and drained wetlands, feedlots, sensitive and unique landscape features, soil types or classifications, ALASD sludge applications, etc., to enhance watershed-scale land management planning and decision-making. G. Research and solicit old aerials, photographs, or historic accounts that depict early landscape and habitat characteristics and changes over time to better assess and visualize cumulative impacts of development. H. Promote and support an expanded water quality monitoring program to include collecting water samples from ditches, tributaries, and discharge pipes to better characterize nutrient delivery, quantities, and source. Testing should encompass flowage from Pocket and Mud lakes. I. Seek cost-efficient means to measure recreational use, fishing pressure, and angling yields. In absence of more cost efficient measures, pursue funding to conduct year round creel surveys in advance of management plan redraft. J. Periodically re-assess the existing condition and potential use of gamefish spawning areas, and if appropriate, identify enhancement options to tributary flowages from the north (Sunset Bay) and Lake Andrew. Assess spawning use and egg deposition in relationship to water level. K. Work with the Lake Association to identify and catalog undeveloped shoreline parcels abutting important fisheries habitat, determine ownership, and promote actions to perpetually preserve these areas from development. L. Encourage the Lake Association to sustain biennial Eurasian water milfoil inspections. M. Work with the Lake Mary Association to develop and periodically distribute a questionnaire from which to identify issues, prioritize lake management programs, and generate a measure of management effectiveness or quality of recreational pursuits afforded by the lake. N. Redraft the Fisheries Management Plan in 2014 or as justified with compelling reasoning. Incorporate specifics of the revised Douglas County Land Use Plan, Lake Association goals, and Watershed Management Plan initiatives. چ 18

Management Milestones Sustained, positive and productive working relationships with the Lake Mary Association Formation of a Lake Mary water quality improvement work group and initiation of focused diagnostic studies geared to determine cause and source of water quality impairment Successful application for a Clean Waters Partnership grant to formalize and fund water quality improvement efforts Completion of a comprehensive digitized watershed database to aid in developmental planning and decision-making Revision of the Douglas County Land Use Plan and Shoreland Management Ordinances to guide developmental growth, protect important fish and wildlife habitats, and minimize runoff and pollutant loading from the watershed چ Potential Plans A. Conduct periodic creel and recreational use surveys to assess fishing pressure, document harvest, quantify fishing satisfaction, etc. in order to assess changes attributable to management initiatives, formulate outcome-based objectives, and generate information from which to justify program expenditures. Survey design should encompass other connected basins to optimize information gained and costs. Cost: $24,000/survey B. Provide funding and technical assistance in a two-year comprehensive water quality monitoring program to include diagnostic evaluations of total nutrient and pollutant loading from private and public drainage systems. Cost: $ 20,000 C. Provide technical support and funding assistance to Douglas County, Lake Mary Township, the Lake Mary Association, or local cooperatives to influence and affect protective land use changes within the watershed and shoreland management zone. Project opportunities may include ditch buffers, manure management, wetland restorations, redirection or treatment of runoff waters in road ditches, shoreline buffers, etc. Cost: $ 50,000 D. Commensurate with sustained catches above management objectives and an understanding of fish movements, act on opportunities to periodically restrict northern pike from important spawning areas. Cost: $1,000 19

E. Dependent upon opportunity and manpower, conduct specialized trapnetting assessments in the spring or fall in those years surveys are scheduled, as a means to effectively sample of black crappie and characterize abundance, growth, and age and size distribution. F. Form partnerships to acquire or negotiate conservation easements on additional undeveloped shoreland areas adjacent to essential or unique near-shore fisheries habitat. Cost: $1,200/shoreline foot G. Develop a pilot project to provide landscaping assistance and funding to shoreland property owners who would be willing to retrofit existing properties to protect water quality. Projects could include shoreline buffers, restoration of wetland areas to retain runoff water and trap pollutants, reduced impervious surfacing, construction of infiltration trenches or temporary ponding sites, regrading, etc. Cost: $ 10,000/project H. Conduct an angler exploitation evaluation to determine the influence of harvest on age and size distribution of black crappie and bluegill. Cost: $ 10,000 I. Dependent upon public support and necessary to prevent over-exploitation, prescribe and implement harvest regulations to sustain fish community balance, achieving management objectives, and improving fishing quality. Species-specific harvest regulation considerations might include, but are not limited to reduced bag limits or size restrictions on walleye, black crappie, or bluegill, or northern pike. J. If availability or condition of spawning habitat is determined to be limiting to consistent walleye recruitment, protect, restore, and/or create artificial spawning substrate. Cost: $50,000 * Potential plans include management activities that may be considered or implemented pending social acceptance, cooperative partnerships, positive cost/benefit analyses, funding, and labor requirements to accomplish and evaluate the specific task. چ 20

Mgmt Classs. Walleye-Centrarchids Primary Species Mgmt Walleye Ecological Class Wae-Centrarcids Secondary Species Mgmt Bass/Panfish/N. pike FOR CENTRAL OFFICE USE ONLY Area Supervisor's Signature Date Entry Date Year Resurvey / / Regional Supervisor's Signature Date Stock Species - Size - Number per Acre Pr/Sec.. Other Lakes in Class 27: Minnewaska, Andrew, Irene, Darling, Moses, Reno Schedule Year Beginning Population Manipulation Yes No Year Development Yes No Year Creel or Use Survey Yes No Year Other 21

Attachment 1 Water Quality Summary: Lake Mary Physical Information DNR Lake ID number: 21-0092 County: DOUGLAS Ecoregion: NCHF Basin: UM Hydrologic Unit Code: 7010108 Surface Area: 2395 (acres) Maximum depth: 34 (feet) Water Quality Data Summary Total Phosphorus Mean: 29 ppb Total Phosphorus Minimum: 5 ppb Total Phosphorus Maximum: 40 ppb Years for which data has been collected Chlorophyll-a Mean: 9.5 ppb Chlorophyll-a Minimum: 1 ppb Chlorophyll-a Maximum: 25 ppb Secchi Disk Mean: 2.1 meters Secchi Disk Minimum: 0 meters Secchi Disk Maximum: 4 meters Carlson Trophic Status Total Phosphorus: 53 Chlorophyll-a: 53 Secchi Disk: 49 Overall Trophic Status: Eutrophic Water Quality Assessment Data Quality: Excellent Aquatic Recreation Use Support: Fully Supporting 22

Attachment 2 Water Level Data Lake Mary, Douglas County Period of record: 07/28/1955 to 05/24/2006 # of readings: 228 Highest recorded: 1371.3 ft (11/01/1986) Lowest recorded: 1365.99 ft (01/25/1989) Recorded range: 5.31 ft Average water level: 1368.54 ft OHW elevation: 1369.1 ft Datum: 1929 (ft) 23

Attachment 3 Population Summaries: Lake Mary, Douglas County, Lake Class 27 Gamefish Survey Catch Rates Growth Size Structure Walleye Fish/Gillnet 27 24 21 18 15 12 9 6 3 0 Objective: 15.0/Gillnet 23.3 19.3 17.5 18 16.2 13.9 12.8 13.3 13.5 10.2 10.4 10 Actual & range of expected catches '82 '85 '86 '87 '88 '89 '90 '91 '93 '97 '01 '05 Year of Survey Objective: 14.5 at age-3 2005 Average 13.8 at age-3 Objective: PSD > 50 RSD-P > 15 2005 Captures PSD: 57 RSD-P: 9 Northern pike Fish/Gillnet 24 20 16 12 8 4 10.1 Objective: < 5.0/Gillnet 12.3 12.5 14.1 9.3 6.8 6.1 5 4.7 4.2 Actual & range of expected catches 11.5 2.3 Objective: 21 by age-4 2005 Average 20.8 at age-4 Objective: PSD > 50 RSD-P > 10 2005 Captures PSD: 18 0 '82 '85 '86 '87 '88 '89 '90 '91 '93 '97 '01 '05 Year of Survey Yellow perch Fish/Gillnet 50 45 40 35 30 25 20 15 10 5 0 Objective: > 20.0/Gillnet Actual & range of expected catches 15 15.2 6.8 7.8 7.9 7.3 9.8 2.7 2 2.7 2.9 0.4 '82 '85 '86 '87 '88 '89 '90 '91 '93 '97 '01 '05 Year of Survey Objective: -- 2005 Average -- Objective: PSD of 10-20 2005 Captures PSD: 14 24

Objective: 40 60/Hour Objective: < 5.0/Gillnet Attachment 3 Continued Population Summaries: Lake Mary, Douglas County, Lake Class 27 Gamefish Survey Catch Rates Growth Size Structure LM Bass Fish/Hour 120 100 80 60 40 20 Objective: 40-60/hr 50 24.7 89.4 44.7 Objective: 15.0 at age-6 2005 Average: 14.5 at age-6 Objective: PSD > 60 RSD-P > 20 2005 Captures: PSD: 58 RSD-P: 6 0 1993 1997 2001 2005 Year of Survey Black Crappie Fish/Trapnet 5.0 4.0 3.0 2.0 1.0 0.0 Objective: > 1.2/Trapnet 3.2 2.7 2 2.1 1.8 1 1 1.1 0.8 0.9 1 0.7 Actual & range of expected catches '82 '85 '86 '87 '88 '89 '90 '91 '93 '97 '01 '05 Year of Survey Objective: 10.0 at age-5 2005 Average: Insufficient sample size Objective: RSD-P > 20 2005 Captures: PSD: 78 RSD-P: 22 80 60 54.2 Objective: 10-15/Trapnet Objective: 7.0 by age-6 Objective: PSD > 50 Bluegill Fish/Trapnet 40 20 31.9 38.6 37.1 33.7 33.2 23.7 20.8 19.1 Actual & range of expected catches 10.2 12.6 12.5 2005 Average: 7.5 at age-5 2005 Captures: PSD: 40 RSD-P: 3 0 '82 '85 '86 '87 '88 '89 '90 '91 '93 '97 '01 '05 Year of Survey 25

Attachment 4 Fall, Young-of-Year Walleye Catches Lake Mary, Douglas County Electrofishing CPUE Year (walleye/hour) 1990 4.0 1991 -- 1992 18.5 1993 0.0 1994 54.0 1995 12.0 1996 79.0 1997 6.0 1998 30.0 1999 56.8 2000 70.0 2001 53.7 2002 117.0 2003 0.8 2004 219.5 2005 5.0 2006 158.1 Running Mean 55.3 26

Fish Management Plan Progress/Comment Sheet Region Area DOW# County Lake Class Acreage NW Glenwood F116 21-092 Douglas Mary 27 SA 2,371 LA 1,020 Date Action Category: Inventory Achievements/Observations/Comments Date Action Category: Stocking & Other Direct Fish Management Achievements/Observations/Comments Northern pike Date Date Date Date Date Action Category: Habitat Protection/Enhancement Achievements/Observations/Comments Action Category: Harvest Management/Regulations Achievements/Observations/Comments Action Category: Education Achievements/Observations/Comments Action Category: Cooperation/Integration Achievements/Observations/Comments Action Category: Other Achievements/Observations/Comments 27

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