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Salim Heddam - One of the best experts on this subject based on the ideXlab platform.

  • use of optimally pruned extreme learning machine op elm in forecasting dissolved oxygen concentration do several hours in advance a case study from the klamath river oregon usa
    Environmental Processes, 2016
    Co-Authors: Salim Heddam
    Abstract:

    This study presents a new method called optimally pruned extreme learning machine (OP-ELM) for forecasting dissolved oxygen concentration (DO) several hours in advance. The forecast time horizon ranges from 24-h ahead (one day) to 168-h ahead (seven days). The proposed OP-ELM model is compared to the standard multilayer perceptron neural network (MLPNN) with respect to their capabilities of forecasting DO in the Klamath River at Miller Island Boat Ramp, Oregon, USA. To demonstrate the forecasting capability of OP-ELM and MLPNN models, we used a long-term data set of hourly DO data for a ten-year period, from 1 January 2004 to 31 December 2013, collected by the United States Geological Survey (USGS Stations No: 420,853,121,505,500 [Top] and 420,853,121,505,501 [Bottom]). For developing the models, we split the data set into a training subset (from 2004 to 2010) that corresponded to 70 %, and a validation (from 2011 to 2013) that corresponded to 30 % of the total data set. We investigated the performance and accuracy of the proposed two models for three different horizons, i.e., short-term, medium-term and long-term forecasting; a total of six different models (FM1 to FM6), having the same data sets as inputs, were developed for short-term (24 h to 48 h), medium-term (72 h to 96 h) and long-term (120 h to 168 h) horizons. Input variables used in the six models were the six antecedent DO concentrations at (t-5), (t-4), (t-3), (t-2), (t-1) and (t). The performance of the OP-ELM and MLPNN models in training and validation sets were compared with the observed data. To get more accurate evaluation of the results of the two models, the following seven statistical performance indices were used: the coefficient of correlation (R), the Willmott index of agreement (d), the Nash-Sutcliffe efficiency (NSE), the root mean squared error (RMSE), the mean absolute error (MAE), the bias error (Bias), and the mean absolute percentage error (MAPE). The study reveals that OP-ELM and MLPN provided good results and they were successful in forecasting DO at a high level of accuracy. The reliability of forecasting decreased with increasing the step ahead. The measures of model performance fell within the acceptable ranges for the two stations. Regarding the fact that researches on medium and long-term forecasting are relatively limited, the present work aims to build and provide a good early warning system capable of preventing DO depletion and the associated problems of anoxia and hypoxia in river. Furthermore, the proposed forecasting models, when implemented appropriately, could be reliably used in detecting future change in DO concentration in rivers.

  • modelling hourly dissolved oxygen concentration do using dynamic evolving neural fuzzy inference system denfis based approach case study of klamath river at miller island Boat Ramp or usa
    Environmental Science and Pollution Research, 2014
    Co-Authors: Salim Heddam
    Abstract:

    In this study, we present application of an artificial intelligence (AI) technique model called dynamic evolving neural-fuzzy inference system (DENFIS) based on an evolving clustering method (ECM), for modelling dissolved oxygen concentration in a river. To demonstrate the forecasting capability of DENFIS, a one year period from 1 January 2009 to 30 December 2009, of hourly experimental water quality data collected by the United States Geological Survey (USGS Station No: 420853121505500) station at Klamath River at Miller Island Boat Ramp, OR, USA, were used for model development. Two DENFIS-based models are presented and compared. The two DENFIS systems are: (1) offline-based system named DENFIS-OF, and (2) online-based system, named DENFIS-ON. The input variables used for the two models are water pH, temperature, specific conductance, and sensor depth. The performances of the models are evaluated using root mean square errors (RMSE), mean absolute error (MAE), Willmott index of agreement (d) and correlation coefficient (CC) statistics. The lowest root mean square error and highest correlation coefficient values were obtained with the DENFIS-ON method. The results obtained with DENFIS models are compared with linear (multiple linear regression, MLR) and nonlinear (multi-layer perceptron neural networks, MLPNN) methods. This study demonstrates that DENFIS-ON investigated herein outperforms all the proposed techniques for DO modelling.

Tim J. Langlois - One of the best experts on this subject based on the ideXlab platform.

  • Quantifying shark depredation in a recreational fishery in the Ningaloo Marine Park and Exmouth Gulf, Western Australia
    Marine Ecology Progress Series, 2018
    Co-Authors: J. D. Mitchell, Dianne L. Mclean, Shaun P. Collin, S. Taylor, G. Jackson, Rebecca Fisher, Tim J. Langlois
    Abstract:

    The authors thank all of the recreational fishers interviewed throughout the Boat Ramp surveys, without whom the study would not have been possible. Gratitude is also extended to the Department of Biodiversity Conservation and Attractions, Government of Western Australia, for supplying Boat Ramp visitation data, and to the US National Oceanic and Atmospheric Administration for providing SST data for this study. Peter Barnes from the Department of Biodiversity Conservation and Attractions provided local support and information relating to the fishery and the Ningaloo Marine Park. Thanks also go to Claire Smallwood and Karina Ryan from The Department of Primary Industries and Regional Development, Government of Western Australia, for their advice on Boat Ramp survey design. Brett Molony and Stephen Newman from the Department of Primary Industries and Regional Development also provided important background information on the recreational and commercial fisheries in this region, as well as useful feedback on the manuscript. Matias Braccini is thanked for offering guidance on the statistical analysis conducted in this study. Matt Gillett and Leyland Campbell from Recfishwest provided information on recreational fishing in Western Australia. Lastly, the authors thank Rory McAuley, Alastair Harry and Hannah Zilles from The Department of Primary Industries and Regional Development, Government of Western Australia, as well as 3 other anonymous reviewers, for providing feedback on the manuscript. This study was funded by the Australian Federal Government and The University of Western Australia, through an International Postgraduate Research Scholarship and Australian Postgraduate Award for J.D.M, with additional funding also received from the Jock Clough Marine Foundation.

Emma L. Johnston - One of the best experts on this subject based on the ideXlab platform.

  • Map of the Clyde Estuary study sites located on the south east coast of Australia.
    2015
    Co-Authors: Vivian X. Y. Sim, Katherine A. Dafforn, Stuart L. Simpson, Brendan P. Kelaher, Emma L. Johnston
    Abstract:

    Sites include Boating structures (B1—Boat Ramp 1, M—marina, J—jetty, B2—Boat Ramp 2) reference sites (R1-R9). All Boating structures and reference sites R7-R9 were located within the designated special purpose zone. Reference sites R1-R6 were located within the habitat protection zone of Batemans Marine Park.

  • Sediment infauna abundance and diversity in Batemans Marine Park.
    2015
    Co-Authors: Vivian X. Y. Sim, Katherine A. Dafforn, Stuart L. Simpson, Brendan P. Kelaher, Emma L. Johnston
    Abstract:

    Mean abundances (+/-S.E.) of (a) Polychaetes, (b) Amphipods, (c) Copepods, (d) Nematodes, (e) Nemerteans and (f) Taxa richness and (g) Total abundance comparing Boating structures within a special purpose zone to reference sites within special purpose and habitat protection zones in Batemans Marine Park. Sites include Boating structures (B1—Boat Ramp 1, M—marina, J—jetty, B2 —Boat Ramp 2) reference sites (R1-R9). White bars are reference sites and black bars are Boating structures.

  • Contaminant concentrations and environmental variables in Batemans Marine Park.
    2015
    Co-Authors: Vivian X. Y. Sim, Katherine A. Dafforn, Stuart L. Simpson, Brendan P. Kelaher, Emma L. Johnston
    Abstract:

    Mean (+/-S.E.) metal concentrations (μg/g) are shown for a) copper, b) lead, c)zinc and mean (+/-S.E.) d) silt content (% < 63 μm), e) temperature and f) salinity comparing Boating structures within a special purpose zone to reference sites within special purpose and habitat protection zones in Batemans Marine Park. Sites include Boating structures (B1—Boat Ramp 1, M—marina, J—jetty, B2—Boat Ramp 2) reference sites (R1-R9). White bars are reference sites and black bars are Boating structures.

J. D. Mitchell - One of the best experts on this subject based on the ideXlab platform.

  • Quantifying shark depredation in a recreational fishery in the Ningaloo Marine Park and Exmouth Gulf, Western Australia
    Marine Ecology Progress Series, 2018
    Co-Authors: J. D. Mitchell, Dianne L. Mclean, Shaun P. Collin, S. Taylor, G. Jackson, Rebecca Fisher, Tim J. Langlois
    Abstract:

    The authors thank all of the recreational fishers interviewed throughout the Boat Ramp surveys, without whom the study would not have been possible. Gratitude is also extended to the Department of Biodiversity Conservation and Attractions, Government of Western Australia, for supplying Boat Ramp visitation data, and to the US National Oceanic and Atmospheric Administration for providing SST data for this study. Peter Barnes from the Department of Biodiversity Conservation and Attractions provided local support and information relating to the fishery and the Ningaloo Marine Park. Thanks also go to Claire Smallwood and Karina Ryan from The Department of Primary Industries and Regional Development, Government of Western Australia, for their advice on Boat Ramp survey design. Brett Molony and Stephen Newman from the Department of Primary Industries and Regional Development also provided important background information on the recreational and commercial fisheries in this region, as well as useful feedback on the manuscript. Matias Braccini is thanked for offering guidance on the statistical analysis conducted in this study. Matt Gillett and Leyland Campbell from Recfishwest provided information on recreational fishing in Western Australia. Lastly, the authors thank Rory McAuley, Alastair Harry and Hannah Zilles from The Department of Primary Industries and Regional Development, Government of Western Australia, as well as 3 other anonymous reviewers, for providing feedback on the manuscript. This study was funded by the Australian Federal Government and The University of Western Australia, through an International Postgraduate Research Scholarship and Australian Postgraduate Award for J.D.M, with additional funding also received from the Jock Clough Marine Foundation.

Diana, Matthew J. - One of the best experts on this subject based on the ideXlab platform.

  • Surveys and investigations for sportfish management in lakes and rivers in Illinois
    Illinois Natural History Survey, 2013
    Co-Authors: Diana, Matthew J., Nannini, Michael A., Gring, Jeffery P., Garavaglia, James A., Wahl, David H.
    Abstract:

    Sportfishing in Illinois is a major recreational activity and source of revenue and proper management of fish populations is paramount to maintaining the quality of the resource. Many different management strategies can be implemented in an attempt to improve the fishery, often without adequate evaluation. Management decisions utilize techniques that may improve the fishery in a particular system. Management techniques often are implemented without being evaluated using scientific methods and instead are based on anecdotal evidence. It is important to evaluate management practices in order to further understand if they are producing the desired fishery and if the current management action addresses the factors that may be limiting to a fishery. Therefore there is a need for more intensive scientific evaluation of management techniques in order to provide managers with evidence that these techniques can be used to produce the desired benefits.Stocking is a common tool utilized in Illinois to increase largemouth bass populations. However survival of stocked fish has been documented to be low when stocked on top of natural populations. There are a number of techniques that need to be evaluated to determine if stocking survival can be increased. We continued evaluating stocking techniques to improve survival of stocked largemouth bass. Three lakes were stocked with largemouth bass, with half the fish stocked at the Boat Ramp and half dispersed throughout the lake and into woody or vegetated habitat. Very few stocked fish have been recaptured from any stockings conducted thus far regardless of method. No one stocking method experienced greater growth or survival and the increased handling may contribute to the low survival. CPUE of stocked fish in this experiment has been lower than observed in stockings conducted in previous studies we have conducted and we hope to observe greater survival in future segments in order to evaluate the success of these two stocking strategies.Muskellunge are commonly stocked in Illinois as there is no documented successful reproduction. It is unclear what stock of muskellunge is best suited to maximize growth and survival in Illinois waters. We conducted final sampling during this segment and in this report present final summary of growth and survival comparisons among the three stocks from Mingo, Pierce, and Sam Dale Lakes. We compare growth and survival of muskellunge from the Upper Mississippi River drainage stock, the Ohio River drainage stock, and the Illinois North Spring Lake progeny in these three Illinois lakes. Populations were sampled by electrofishing and modified fyke net surveys during spring. Data was compiled from all years to describe long-term trends in growth and survival of muskellunge stocks in Illinois. Across years and lakes, the Ohio River drainage stock and the Illinois population generally appear to have similar growth rates through adulthood. Few Upper Mississippi River drainage stock were available for growth comparisons. Analysis of body morphology indicates that fish from the Upper Mississippi River drainage are consistently leaner than those of the other stocks. Results from lake introductions suggest that after the first summer following stocking, the Ohio River drainage stock and Illinois population typically have similar rates of survival, both of which are higher than the Upper Mississippi River drainage stock. This pattern led to consistently lower survival of Upper Mississippi River drainage stock year classes to adulthood as well. The Ohio River drainage stock and Illinois population show similar survival both to adulthood and annually through adult age classes. The specific mechanism responsible for differences in survival rate among stocks is still unknown. Information on growth and survival of muskellunge stocks at varying latitudes will aid in source selection and optimization of limited hatchery resources. Based on these results, we recommend stocking Ohio River drainage or Spring Lake progeny in Illinois lakes. Mississippi River drainage fish will have lower growth and survival in Illinois than these two populations.In addition to largemouth bass and muskellunge, crappie are commonly stocked to enhance populations. Blacknose crappie have recently been used in stocking efforts because of their distinct mark and their ability to survive handling and hatchery truck transport. Blacknose are a type of black crappie that was originally stocked because the distinct mark and the low occurrence in the wild made it easy to identify stocked fish to evaluate stocking success. There has been some suggestion that blacknose crappie have potential growth and fitness advantages over black crappie, but this has been untested in the field. In addition, little is known about the interbreeding of blacknose crappie with native black crappie or the white crappie species. In this segment, we collected black, white and blacknose crappie from source populations in Illinois and established brood ponds at the Sam Parr Biological Station. In addition blacknose crappie were obtained from Tennessee to compare to the Illinois naturalized fish. In the next segment, we will stock and evaluate the relative growth of age-0 white, black, and blacknose crappie in experimental ponds. When rearing ponds are drained in the next segment, we will estimate abundance and growth of white, black, blacknose, and black x blacknose hybrid crappie as well as the prevalence of the black stripe in the blacknose and black x blacknose hybrid ponds. In addition, we aided in blacknose crappie brood stock collection for the Jake Wolf Memorial Fish Hatchery to establish rearing ponds. Fish reared at the hatchery will be used to stock the Illinois River in the Starved Rock Pool (RM 240) near Ottawa, IL. We will also evaluate the success of this stocking in the next segment. Harvest regulations are commonly employed by fisheries managers to protect overharvest of fish populations or manage size structure. There are a large variety of regulations used in Illinois with varying management goals. In this study, we continued to assess largemouth bass populations in lakes with varying harvest regulations. The default largemouth bass regulation in Illinois is no length limit with a 6 fish bag. This was by far the most common regulation, followed by a standard 14 inch 6 fish bag. We observed some evidence that lakes with slot limits had a greater number of memorable fish, but no significant differences in abundance in any size class of largemouth bass was detected. Lakes with restrictive regulations showed similar largemouth bass size structure and abundance as lakes allowingallharvest. Low harvest ratesor poor compliance to regulations may result in no differences and will be evaluated in future segments.We also began to examine crappie regulations in Illinois lakes and how they relate to crappie populations. We determined regulations for lakes with DNR data available in the FAS database resulting in 327 lakes (46 white crappie only, 137 black crappie only, and 144 with both. Most lakes had unregulated crappie populations. The most common regulation types were bag limits and length/bag limits. Bag limits ranged from 5 -30 fish per day and length limits were either 9 or 10 inches. We found that lakes with length/bag regulations have significantly higher CPUEs than lakes with bag limits or lakes with no regulations. CPUE of crappie from lakes with bag limits was not different than unregulated lakes.Length and bag regulations may be appropriate to utilize to increase the number of crappie in a lake. We will continue to examine crappie regulations and include information on size structure in future reports.Angling tournaments are becoming increasingly popular. Although most tournaments practice live release, there can be high delayed mortality or a variety of sub-lethal impacts of competitive angling tournaments on the individual fish. Previous research has focused on measuring and reducing the stress of individual fish caught in tournaments, but little work has focused on the effect of these practices on the entire fish population. In this study, we continued to assess tournament activity and make comparisons with largemouth bass populations in a number of lakes in Illinois.We contacted lake managers and tournament directors to obtain competitive bass fishing tournament results to quantify the level of tournament activity on a lake and relate it to largemouth bass populations. Information from tournaments conducted on 12lakes was used to evaluate varying tournament pressure in addition to 4 lakes with no tournaments activity. Tournament pressure (angler hours per acre) varied from 0 to 21.8 hours/acre and the mean number of tournaments a year was 19 (range 0 –57). Larger lakes tended to have larger tournaments with a higher number of participants, but lake size was not related to total tournament pressure or the number of tournaments. The CPUE of memorable sized fish in electrofishing samples was the only fish population variable that was related to tournament pressure. Lakes with higher tournament pressure had fewer memorable sized fish in electrofishing samples. We did not detect any changes in abundance or size structure of largemouth bass vulnerable to tournament angling (> 355 mm) or production of young-of-year fish related to tournament pressure. We will continue to collect tournament and largemouth bass population data on these lakes and add additional lakes to this analysis as part of future segments to further understand the influence of tournaments on largemouth bass populations.In addition we have conducted experimental tournament angling on Ridge Lake in order to determine how tournaments can effect reproduction, abundance, and growth of largemouth bass. In this segment, we conducted spring largemouth bass tournaments while fish were on the nest and compared the changes in the fish population to previous years with tournaments and years with no tournaments. We observed no consistent changes in young-of-year production or adult abundance for largemouth bass that was related to tournament activity in the spring. We will continue to alternate tournament and no tournament years to further evaluate the potential effects of tournaments on lake wide recruitment.In addition to stocking and regulations, habitat restoration is critical to managing sportfish populations. The lack of suitable habitat for sportfish spawning, feeding and cover from predators can greatly limit a population. Understanding the importance of habitat and how to manage habitat conditions is important to managers. We have continued to conduct habitat manipulations in a number of lakes in an attempt to enhance largemouth bass populations. We continue to evaluate vegetation plantings at Lake Paradise, drawdown and rotenone efforts at Dolan and Woods Lakes, and vegetation removal through chemical treatments at Airport and Stillwater Lakes. We have observed little change in largemouth bass populations at Lake Paradise due to difficulties in establishing vegetation. Woods Lake is currently drawn down and will be rotenone treated to remove gizzard shad and carp this winter. We will begin evaluating fish populations when it is allowed to refill. Dolan Lake was drawn down to encourage vegetation establishment and rotenone treated to remove gizzard shad and carp. Despite a rebound in the gizzard shad densities, carp have not reestablished in the lake and the vegetation cover has significantly increased coinciding with an increase in largemouth bass densities in this lake. Vegetation removal treatments at Airport Lake have not been entirely successful. We have not been able to document a decrease in vegetation density and therefore no changes in largemouth bass populations were observed. Stillwater Lake was successfully treated for vegetation and the lake has remained at a lower vegetation density following initial treatment. We have also been measuring vegetation density and cover in 11 lakes and evaluate how largemouth bass populations vary among different vegetation types, cover, and fluctuations.We observed few differences in catch rates for young-of-year or adult largemouth bass associated with vegetation cover or shoreline vegetation in 2012. Vegetation has traditionally been related to prey resources (benthic invertebrates, zooplankton, prey fish) however it was not significantly related in 2012. We will continue to evaluate trends in fish populations related to vegetation density in future segments.It is important to quantify habitat in a system in order to fully understand factors that may be limiting a fishery. In mid-sized rivers there is not a standardized method for evaluating habitat in Illinois. Research is needed to create a habitat evaluation method for mid-sized rivers and relate these habitat measures to fish populations.We initiated a project in this segment to address sampling needs for non wadable river habitat and relate habitat to fish communities. We have begun to develop and implement a technique using side scan sonar to map river habitat. We will be able to use this technique to quantify habitat types along with more tradition sampling methods. We will sample fish associated with each habitat type and evaluate relationships between them initially in the Kaskaskia River and expanding to other rivers in future segments.Reproduction and the survival of fish to adulthood can be influenced by a multitude of factors. Understanding variables related to recruitment of fish populations can aid in developing management strategies or identifying limiting factors in a system. Many management practices are focused on enhancing natural recruitment by reducing mortality through practices such as fishing refuges or escapement barriers. Fishing refuges can limit disturbance of fish populations during spawning and protect juvenile and adult fish from fishing mortality and may increase natural recruitment, but have not been well evaluated. We continued to assess two fishing refuges in Otter Lake to determine the potential benefits to spawning and survival of largemouth bass. We observed no differences in CPUE or seine catch of young-of-year or adult largemouth bass in closed refuge sites and sites opento fishing. The refuge has only been in place for 3 years and it may take more time to benefit the fish population. Previous research at Clinton Lake showed increases in largemouth bass numbers in refuge locations, but the results were not evident until after a few years. We will continue to follow changes in the largemouth bass population in Otter Lake to determine how they are influenced by closed fishing refuges. Emigration or “escapement” of sportfish from reservoirs over the impounding barrier is commonly viewed as a major limitation in the successful development of high density populations. Reports and anecdotal evidence suggest that this problem is particularly ubiquitous for muskellunge in the Midwest. However, little documented information exists on the patterns and magnitude of escapement, particularly for fish that occur in low densities such as muskellunge.In this segment, we continued to monitor muskellunge escapement in Lakes Mingo and Sam Dale. Both lakes have a PIT tag array installed on the spillway that will monitor the passage of any tagged fish. Muskellunge were captured in the spring during four weeks of fyke netting. We determined population estimates using mark recapture techniques and PIT tagged all muskellunge upon release.Despite observing high levels of spillway escapement in 2011 at Sam Dale, escapement was not observed in either lake in 2012. In 2012, there was little flow over the dams due to a dry summer season and we did not observe any escapement of muskellunge. Spring rain in 2013 has provided the potential of spillway escapement. We will download data from the receivers and report our observations in the next segment.In this segment, we began to evaluate crappie recruitment in a number of lakes. We initiated spring and fall electrofishing and fyke netting to assess white, black, and blacknose crappie populations. We collected fish for dissection and otolith reading to determine age, growth, and maturity status. We also collected samples to assess prey resources and predator abundance in each study lake. We collected monthly water quality, zooplankton, larval fish and seasonal benthic invertebrate samples. Vegetation was surveyed in June and August and water level was recorded. In future segments we will use this data to determine what factors are related to crappie recruitment and make recommendations for managing crappie populations.In order to assess sportfish populations and compare populations across Illinois, it is critical to use standardized gears that are efficient in collecting the targeted fish species. Standardized practices for population assessments in Illinois have traditionally been AC shoreline electrofishing. Alternative electrofishing gears using direct current have become more popular recently due to perceived greater efficiency for certain species of fish. There is a need to evaluate how catch rates vary between the AC and DC electrofishing inorder to compare historic data if gear changes are made. We conducted AC and DC electrofishing runs on four lakes in both spring and fall. Catch rates for largemouth bass, crappie, and bluegill were similar for both small and large fish between gears. We did observe greater catch rates for gizzard shad and common carp when using DC gear. We will continue to conduct AC and DC sampling and future analyses will focus on more species and the size of fish that is captured.IDNR Division of Fisheries U.S. Fish & Wildlife Serviceunpublishednot peer reviewe

  • Factors Influencing Largemouth Bass Recruitment: Implications For The Illinois Management And Stocking Program
    Illinois Natural History Survey, 2011
    Co-Authors: Diana, Matthew J., Nannini, Michael A., Deboom, Corey S., Mulhollem, Joshua J., Philipp, David P., Wahl, David H.
    Abstract:

    During the past segment, all activities outlined in the annual work plan were accomplished and within the specified budget. The goal of this study is to develop management strategies that maximize growth, recruitment, and harvest of largemouth bass Micropterus salmoides in Illinois impoundments. Largemouth bass are frequently stocked in many Illinois impoundments to compensate for variable recruitment. Even so, the long-term contribution of stocked fish to recruitment and harvest of natural bass populations is unknown and we are addressing these questions. In addition, information on the importance of rearing technique, size of stocked fish, forage base, cover, resident predators, physical-chemical conditions, and stocking stress in determining largemouth bass stocking success is needed to optimize use of hatchery produced fish. Because stocking is only one of several management options for this species, it is critical that additional information on factors limiting recruitment processes be identified.There was no new activity in Job 101.1 as final recommendations were presented in previous reports. In Job 101.2, we continued our evaluation of stocking success of largemouth bass. We conducted additional dataanalysis ina study comparing intensive and extensive rearing techniques. Intensively reared fish were raised in raceways and fed pellets, whereasextensively reared fish were raised in ponds and fed zooplankton and minnows. Extensivelyreared fish experienced better survival through the spring following stocking, but by the following fall (age-1) there was no difference in abundance between the two rearing techniques. We observed a high level of variation inthe number of fish producedinthe rearing ponds. Cost of rearing was much higher for the extensively reared fish for both hatchery ponds and lake side rearing facilities. Higher initial survival and larger size in the fall of extensively reared fish initially appears to justify the added cost. However, long term survival was low for both rearing types and very few stocked fish were recruited to the fishery. In this segment, we also continued to evaluate different stocking techniques to improve survival of stocked largemouth bass. Three lakes were stocked with largemouth bass, with half the fish stocked at the Boat Ramp and half dispersed throughout the lake and into woody or vegetated habitat. Very few stocked fish have been recaptured from any stockings conducted thus far regardless of method. We plan to continue additional stockings and adjust stocking time to minimize high temperatures and potential related mortality. CPUE of stocked fish in this experiment has been lower than observed in stockings conducted asprevious partsof this project and we hope to observe greater survival in the future in order to evaluate the success of these two stocking strategies.In Job 101.3, we evaluated the survival and reproductive success of stocked largemouth bass relative to resident populations. To determine the contribution of stocked fish, the MDH B2B2 allele was used as a genetic tag for fingerlings stocked into six study lakes. Once these fish were part of the reproducing population, it was possible to assess the reproductive success and recruitment of these stocked fish in five of the six lakes by comparing the pre-stocking with post stocking MDH B2 allele frequencies. We also looked at lake size and resident bass CPUE as a possible factors that may have influenced reproductive success. Stocked fish survival to adulthood was variable in the five study lakes, ranging from less than 10% to around 35%. Contribution of stocked fish to reproduction was also variable and was higher in small lakes than in larger ones. The density of resident bass as measured by CPUE had no relationship to the contribution of stocked bass reproduction in the lakes that we studied. Based on the proportion of stocked adults in the populations we could predict the change in the frequency of the MDH B2 allele to determine how reproductive success of stocked fish compared to wild fish. We found that reproductive success of stocked fish was similar to wild fish. Our results indicate that stocking is most likely to be successful in small lakes and that the genetic influence of stocked fish will persist in successive generations. In future reports, we will examine how prey availability could affect stocked largemouth bass condition and ability to secure good nesting sites differently than wild fish. In Job 101.4, we continued a multi lake experiment examining the influence of vegetation on largemouth bass recruitment. Lakes were divided into treatments by the vegetation management strategy. Two lakes (Stillwater and Airport) were treated for vegetation to reduce the vegetation present and yield more intermediate vegetation densities. The vegetation treatments were initiated in this segment and have been successful at reducing vegetation in Stillwater Lake, but not Airport Lake. Two lakes (Paradise and Dolan) experienced management to increase vegetation. Vegetation planting was initiated in 2008in Lake Paradiseand planting efforts continued in this segment. We areevaluating the success of different species of vegetation and the size of cage used. American pondweed has shown the greatest long-term survival and the large cages have been most effective in producing vegetation. In this segment, American pondweed was planted in 5 additional cages and a number of cages were expanded to promotethe spread of successful cages. We also evaluated fish and invertebrate communities associated with vegetated and non-vegetatedcages and observed higher densities of both fish and invertebrates in vegetated cages. Rehabilitation at Dolan Lake has continued to yield higher vegetation and reduced gizzard shad and carp numbers. There is some evidence of gizzard shad populations rebounding. Four lakes with experimental treatments and 7control lakes were monitored for fish populations, vegetation densities, and prey organisms and will be compared through time as the management experiment continues.CPUE of young of year largemouth bass was higher in lakes with greater vegetation densities, but differences were not significant. The density of larval gizzard shad was significantly correlated with the proportion of lake area and perimeter that was vegetated. No other lake conditions that were measured were related to vegetation density. We will continue to monitor vegetation, fish, and prey communities in the 11 research lakes to evaluate the role of vegetation management to increase largemouth bass recruitment.In this segment, we also continuedto examine patterns in abundance of young-of-year largemouth bass, other fish species, and associated biotic communities a mong vegetated, woody, and open lakeshore habitat types in two Illinois lakes. While we did not find significant differences in age-0 largemouth bass densities among the microhabitat types sampled in our enclosure surveys, we did find significant differences in the community composition and abundance of potentially important prey items (juvenile sunfishes, caddisflies, chironomids, stoneflies and cyclopoid copepods). Increases in abundance of potential invertebrate and fish prey in vegetated and wooded sites supports the idea that these habitats are important sources of littoral productivity. There is potential for dam escapement to influence largemouth bass recruitment. To assess dam escapement, we sampled downstream of the dam on two reservoirs, Ridge Lake and Forbes Lake via backpack electrofishing and seines. Some largemouth bass were observed in sampling below the dam at both Forbes and Ridge Lake following high water events however there were few fish in all sampling. The assessment of dam escapement is in the very early stages of implementation and evaluation and much more data is needed to draw conclusions about the effect of escapement on largemouth bass populations and recruitment. Additional data will be collected so that a baseline can be established in order to compare largemouth bass numbers after an increased discharge event to largemouth bass numbers during low flow periods. There is potential for angling to have a large influence on largemouth bass populations. Competitive tournament fishing for black bass has grown rapidly over the past several years. Previous work has shown high levels of mortality associated with these tournaments in other parts of the United States. However, little is known about the effects of tournaments on largemouth bass recruitment. In Job 101.5, we continued to examine effects of tournaments for largemouth bass. In this segment, we also continued monitoring largemouth bass spawning activities at Lincoln Trail Lake. Water clarity limited our ability to identify largemouth bass nests in spring 2011. We will continue to evaluate nesting activity, nest guarding behavior, vulnerability to angling, and nest predation in future segments. In this segment, we continued to conduct largemouth bass tournaments in alternating years on Ridge Lake to evaluate their effect on recruitment. A series of spring tournaments were conducted in 2007 and 2010 and largemouth bass populations were compared among tournament and non-tournament years. Initial results show no differences in recruitment between tournament and non-tournament years. In addition, no changes were observed in adult largemouth bass abundance or size structure. These results are preliminary and additional years will be needed to evaluate treatment effects. We are continuing a pond experiment examining the population effects of tournament angling during the spawning season on largemouth bass recruitment. In the current segment, we initiated the second year of the two-year study. Results from the first year indicate that tournament angling has a moderate effect on largemouth bass recruitment in terms of numbers, and a rather large effect on young-of-year largemouth bass biomass. After adjustment for summer zooplankton abundance, which was a significant covariate for largemouth bass recruitment, ponds in which tournament angling was conducted had approximately 22% less recruits and 64% less young-of-year biomass than control ponds. In the future segment, we will include data from the second year to strengthen results. In this segment we also continued to evaluate tournament activity on nine Illinois lakes as well as 5 control lakes with no tournaments. Tournament data was used to calculate total tournament angler hours per acre as well as catch rates and statistics on the sizes and types of tournaments on each lake. We evaluated the largemouth bass population in each lake by performing electrofishing transects in the spring. CPUE of young-of-year largemouth bass and largemouth bass over 14 inches was not correlated with tournament pressure (angler hours/acre). The mean number of fish weighed in at a tournament was correlated with CPUE of largemouth bass over 14 inches and was also correlated with lake size. Tournament lakes did not have reduced recruitment when compared to lakes with no tournament angling. Tournament lakes had higher CPUE of largemouth bass larger than 14 inches than control lakes, but it is difficult to separate the effects of tournaments from the size of the lake and the fact that tournaments may target lakes with more abundant adult largemouth bass. We will continue to collect tournament and largemouth bass population data in future segments to further evaluate and understand how tournaments influence largemouth bass populations. In Job 101.6, a portion of Clinton Lake that was closed to fishing was sampled to continue assessment of the effects of a refuge on largemouth bass populations. Electrofishing samples yielded a higher abundance of adult largemouth bass in the refuge than in the main lake. No increase in the number of largemouth bass has been observed throughout the lake. Sampling will continue at Clinton Lake to monitor largemouth bass populations for changes resulting from the refuge. We also continued sampling Otter Lake as an additional location to evaluate refuges. Electrofishing and seine samples were conducted in two refuge sites as well as three control sites. The refuge was closed to fishing in June 2010 and we initiated sampling for post refuge conditions. We also began assessing effects of harvest regulations on largemouth bass populations. In this segment, we expanded our database of lakes using the Fisheries Analysis System (FAS) containing electrofishing data from 2000-2007 collected by DNR biologists. We grouped lakes by regulation type into 7 groups; Bag by Size(Bag limit above and below a specified size), Catch-and Release (no harvest allowed), Standard (14” length limit, 6 fish creel), Lowered Bag (14” length limit, 14” length limit, 6 fish bag limit), Raised Length/Low Bag (>14” length limit,

  • Factors Influencing Largemouth Bass Recruitment: Implications For The Illinois Management And Stocking Program
    Illinois Natural History Survey, 2008
    Co-Authors: Diana, Matthew J., Nannini, Michael A., Deboom, Corey S., Parkos, Joseph J., Pope, Aloah J., Vanlandeghem Matthew, Olds Brett, Einfalt, Lisa M., Claussen, Julie E., Philipp, David P.
    Abstract:

    During the past segment, all activities outlined in the annual work plan were accomplished and within the specified budget. The goal of this study is to develop management strategies that maximize growth, recruitment, and harvest of largemouth bass Micropterus salmoides in Illinois impoundments. Largemouth bass are frequently stocked in many Illinois impoundments to compensate for variable recruitment. Even so, the long-term contribution of stocked fish to recruitment and harvest of natural bass populations is unknown and we are addressing these questions. Because stocking is only one of several management options for this species, it is critical that additional information on factors limiting recruitment processes be identified. In addition, information on the importance of rearing technique, size of stocked fish, forage base, cover, resident predators, physical-chemical conditions, and stocking stress in determining largemouth bass stocking success is needed to optimize use of hatchery produced fish. There was no new activity in Job 101.1 as final recommendations were presented in previous reports. In Job 101.2 we are assessing stocking strategies for largemouth bass. Supplemental stocking is a widely used management tool for increasing the standing stock of an existing population. We evaluated four sizes of stocked fish (50, 100, 150, and 200 mm) that were stocked in four lakes. Survival of stocked largemouth bass fingerlings to adult size was relatively low and ranged from 0 to 2.7 stocked fish per hour of electrofishing during the fall of 2007 and spring of 2008. Scales were collected from each adult stocked fish and will be aged in order to determine which year each fish was stocked and what size it was at stocking. We did not observe any stocked largemouth bass remaining in Woods Lake in 2007 or 2008, however there were stocked fish collected in Lake Charleston, Mingo and Homer. We observed very few stocked largemouth bass remaining and will conclude our sampling for long-term survival with this segment. Data from this segment were combined with previous segments in order to assess differences in growth and survival with varying stocking size. Despite initial differences in size and catch per unit effort (CPUE), all stocked bass were found in similar relative abundances and at similar mean size from the first summer after stocking throughout the following seasons. Cost analysis showed that growing bass to 150 or 200 mm increased the overall cost of producing and stocking largemouth bass without increasing survival. As a result, we recommend stocking four inch bass because small fingerlings do not survive well and no differences in long-term survival exist between medium, large, and advanced fingerlings. In this segment we also continued to evaluate long-term survival and growth of intensively and extensively reared stocked fish. Thus far, no differences in survival have been observed between intensively and extensively reared fish in any of the three study reservoirs. However, the relative survival of intensively and extensively reared largemouth bass did vary between lakes. We are no longer collecting significant numbers of stocked fish in any of the three lakes stocked with intensive and extensively reared fish and sampling was concluded in this segment. Scales were collected from adult fish in electrofishing samples and were aged during this segment by two independent readers. These age data will be used to assign a rearing type to each stocked fish that was collected and will be used to evaluate the long-term survival differences of the fish reared vifrom these different techniques in the next segment. Based on our results thus far, the usefulness of supplemental stocking as a management strategy will vary by individual lake. We initiated a new stocking experiment in this segment to examine the relative advantages of point and dispersed stocking of largemouth bass. We stocked four lakes by both stocking at the Boat Ramp and stocking into habitat at locations around the lake. We observed very low survival to the first fall for stocked fish regardless of stocking strategy. Future stockings will be needed to assess differences in survival and growth. In this segment, we also evaluated the long-term contribution of four-inch stocked largemouth bass from three annual stockings in 15 reservoirs. Stocked largemouth bass were marked with fin clips and sampled for five years. Contribution of stocked fish to the population was highest for young of year (21%) and juvenile bass (17%), but decreased dramatically in adult fish (5%). Catch per unit effort (CPUE) from electrofishing samples was also low for adults resulting in small contributions to the population. Our results suggest limited contribution of stocked fish to adult largemouth bass populations and the size of stocked fish in the first fall following stocking is related to higher CPUE of adult fish. Substantial mortality exists between the age-1 and adult ages of stocked largemouth bass which differs from wild fish that experience low mortality following the first fall. Additional research regarding the importance of predator and prey populations, habitat, and abiotic factors are needed to determine lake characteristics most favorable for stocking largemouth bass. The objective of Job 101.3 is to evaluate the survival and reproductive success of stocked largemouth bass to resident populations. To determine the contribution of stocked fish to a population, fingerlings were produced at the Little Grassy Fish Hatchery with the MDH B2B2 allele as a genetic tag. These genetically tagged fingerling were then stocked into six study lakes. Once these fish reached sexual maturity, it is possible to assess their reproductive success and recruitment to the population by comparing the pre-stocking MDH B2 allele frequencies with the post-stocking MDH B2 allele frequencies. Young-of-the-year produced in 2007 were collected from each of the six study lakes and their allele frequencies determined for the MDH B2 allele. Although it is still early to fully evaluate the effects of stocking, five of the six lakes do show an increase in the MDH B2 allele. Stocking contribution appears to be high in small lakes, but relatively low in larger ones. Further yearly sampling is needed to fully evaluate the long-term impacts of stocked fingerlings in these populations and to fully assess the costs and benefits of largemouth bass stocking programs. In Job 101.4, we assessed which abiotic and biotic factors are associated with variation in recruitment of largemouth bass to age 1. We used the results from previous segments to construct lake-specific regression models of largemouth bass recruitment and then tested their accuracy with data from this segment (2007 year class). In general, differences among lakes in mean recruitment were related to survival of young-of-the-year (YOY) to fall, implying that year class strength differences are set prior to winter. For each individual lake, reproductive output (i.e., spawning stock abundance, peak YOY density) or abundance of larval and juvenile bluegill sunfish were included in models predicting recruitment strength. Lakes where bluegill abundance was not included in recruitment models had very productive bluegill populations; therefore, recruitment in these systems was not limited by prey fish abundance. These models generally over- viiestimated abundance of age 1 recruits in the 2007 year class, but were accurate at predicting if a lake would have either below or above average year class strength. For all year classes examined, YOY largemouth bass exhibited a negative relationship between abundance and growth. Future work involving improvement of habitat availability (i.e., aquatic vegetation) may improve growth rates by increasing the number of YOY individuals that can be sustained by the environment. We also began to evaluate the influence of vegetation and woody habitat on young-of-year largemouth bass and other fish. We sampled 6 enclosures on Lincoln Trail, 3 with vegetation, and 3 without. We observed greater average densities of largemouth bass, bluegill, and all other fish in the vegetated enclosures compared to the non-vegetated enclosures. These differences however were small and we plan to continue this work in Lincoln Trail and expand to additional lakes. We also expanded our analysis of the influence of vegetation and woody debris to largemouth bass recruitment. Lakes were mapped for composition and abundance of vegetation and woody habitat. We observed no direct correlations with vegetation and woody habitat with young-of-year largemouth bass abundance in the fall. In future segments, we will expand these analyses to incorporate additional years of data and evaluate the interaction between vegetation and woody habitat.In this segment, we also identified 13 lakes to include in a multi lake experiment examining the effects of manipulating vegetation on largemouth bass populations. We have identified two low vegetation lakes where we will increase aquatic vegetation. In spring of 2008, we began planting vegetation in fish enclosures in Lake Paradise. Five species of vegetation were planted in varying size and array of enclosures. We will evaluate the different types of enclosures and vegetation species in order to assess the vegetation planting as well as make management recommendations on planting techniques. In fall of 2006 through spring of 2007, Dolan Lake was drawn down and rotenone was applied to reduce carp and gizzard shad abundance and expose the seed banks in an attempt to increase vegetation and sportsfish production. These lakes are being monitored for changes in the fish community. We also began monitoring three high vegetation lakes where we will decrease vegetation levels (Airport Pond, Kakusha Lake, and Stillwater Lake). An additional 8 lakes will be treated as control lakes where no vegetation management will occur. The control lakes vary in vegetative cover from low to high and will be coupled with experimental lakes. We began monitoring these lakes before vegetation treatments to evaluate the effects on largemouth bass recruitment and the fish community. These studies will allow us to make recommendations on vegetation management in order to increase largemouth bass recruitment in Illinois reservoirs. We also began monitoring dam escapement of largemouth bass during high water events. We have observed largemouth bass moving over the dam at Forbes and Ridge Lake. This project is in the initial phase and we will continue to evaluate fish passage during high and low flows to evaluate if escapement can effect largemouth bass recruitment. There is potential for angling to have a large influence on largemouth bass populations. In particular, competitive tournament fishing for black bass has grown rapidly in the United States over the past several years. Previous work has shown high levels of mortality associated with these tournaments in other parts of the United States. viiiIn Job 101.5, we continued monitoring largemouth bass spawning activities at Lincoln Trail Lake. Largemouth bass appeared to prefer cobble, pebble and gravel nesting substrates. Spawning date for young-of-year largemouth bass surviving to the fall was disproportionately skewed towards nests from later in the spawning season in most years. Nesting frequency was also compared to existing water quality parameters. Frequency of new nests was directly related to water temperature. Spawning activity decreased when temperature decreased and no spawning was observed at temperatures under 50o F. Total number of nests was not related with the number of recruits. However, adult standing stock was related to the total number of recruits indicating a stock recruitment driven system. We continued to monitor largemouth bass tournaments in order to assess if reproductively active males are being preferentially caught. Data from three of the four lakes examined suggests that this may be the case during both spring tournaments and the post-spawning period. Information provided by tournament angler surveys suggests that the culling and release of smaller males for larger females is minimal and not skewing sex ratio estimates. Additional research to determine the implications of angling bass from the nest on the overall bass population and year class strength are needed. We continue to determine sex and ages of largemouth bass in lakes with varying fishing exploitation. We will examine how angling activities influence sex specific characteristics such as growth, longevity, and age of maturity. Using this data, we will be able to make predictions about how angling will affect recruitment of largemouth bass. In this segment, we also began to monitor largemouth bass tournaments at Bloomington and Evergreen Lakes in order to assess tournament related mortality and stress related physiology at different times of year. Livewell simulation experiments were also initiated to assess the influence of water temperature and dissolved oxygen on fish exposed to tournament conditions. In addition, pond experiments were implemented to evaluate how holding cages can influence mortality and stress response estimates in the tournament experiments. Results from these experiments will be used to assess the potential impacts of tournament fishing on largemouth bass populations and used to make management recommendations regarding tournament procedures. In Job 101.5, we also conducted a controlled pond experiment at the Aquatic Research Facility in Champaign, IL to assess the effects of angling on largemouth bass recruitment. We tested the effect of brood reduction on young-of-the-year recruitment, and found that predation on largemouth bass nests during catch and release angling events did reduce the number and biomass of YOY surviving later in the first year of life. We will repeat this experiment in 2008 to increase experimental replication so that statistically significant trends may be detected if present. We also conducted a field experiment on Ridge Lake, holding largemouth bass angling tournaments during the spawning season – the first time Ridge has been open to angling during the spawning season since at least 1996. We detected slightly lower than average YOY densities in fall sampling for 2007, indicating that angling during the spawning season and concomitant brood predation may be influencing YOY recruitment later in the first year of life. Data collection and analysis on Ridge Lake will continue in future segments to further explore the relationship between angling and recruitment in a more natural system, while pond experiments will continue to allow for controlled examination of specific, angling-related mechanisms influencing recruitment. ixIn Job 101.6, a portion of Clinton Lake that was closed to fishing was sampled to determine the effects of a refuge on largemouth bass populations. Electrofishing samples yielded a higher abundance of adult largemouth bass in the refuge than in the main lake. Some increase in the number of largemouth bass has also been observed throughout the lake. Sampling will continue at Clinton Lake to monitor largemouth bass populations for changes resulting from the refuge. We also began sampling Otter Lake as an additional location to evaluate refuges. Electrofishing and seine samples were initiated in two proposed refuge sites as well as three control sites. We plan to implement the refuge after several years of monitoring pre refuge conditions in the lake. We also began assessing potential study design and lakes for monitoring effects of harvest regulations on largemouth bass populations. Initial lakes were selected to compare the effects of regulations on largemouth bass populations. INHS study lakes have regulations from standard 14and 15-inch length limits to varying slot limits. We will employ FAS data in future segments to supplement the initial study lakes used in this analysis. We will be specifically targeting assessments of how size limit regulations may influence angler decisions to choose between harvest and release, and how those cumulative decisions may alter population size structure over time. These data can then be used to guide future discussions about various management experiments that might be implemented.none listedunpublishednot peer reviewe