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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Fish population analysis of four selected borrow pit lakes in east- central Indiana

Kirby, Edward B. January 1980 (has links)
Fish populations from four borrow pit lakes were evaluated for growth, condition, and composition. Information obtained from this study was used to formulate management possibilities to improve the sport fishery in these lakes. This study was conducted on four borrow pit lakes in Delaware and Grant Counties along Interstate 69 in eastcentral Indiana from April, 1976 to October, 1976.Growth data revealed that largemouth bass from Cardinal, Dumpert's, and Walter's Lakes did not reach harvestable size (12 in.) until they were 4 or 5 years old. Bass from all three lakes averaged approximately 62 mm for the yearly increment of growth. Bluegill from Cardinal and Walter's Lakes reached harvestable size (5 in.) by age four while bluegill from Dumpert's Lake were 3 years old when they reached harvestable size. Bluegill averaged 26 mm and 28 mm respectively for Cardinal and Walter's Lakes while Dumpert's Lake averaged 42 mm for the yearly increment.Condition data revealed that only the age five bluegill from Dumpert's Lake were classified in good condition. There were no largemouth bass classified in good condition whereas only age five through seven bass in Walter's Lake were classified in average condition.Growth rates for bass and bluegill were less than most values given in the literature with Dumpert's Lake having the fastest growing bass and bluegill. Bluegill was the dominant species captured from all lakes except Cardinal Lake where gizzard shad was the dominant species. Bluegill and largemouth bass averaged 65% and 12% of the population respectively when young-of-the-year fish were included. This study revealed that these lakes should be able to support a warm-water sport fishery with proper management techniques.
2

Population trends of major near-shore fish species in Indiana waters of Lake Michigan

Sapp, Shawn A. January 1999 (has links)
The purpose of this research was to determine population trends of major nearshore fish species in Indiana waters of Lake Michigan from 1984 to 1998 to gain insight into species dynamics. Index trawl samples were collected twice monthly from June through August at three locations. Trends of catch-per-unit-effort (CPUE) were investigated for the most abundant species: yellow perch (Perca flavescens), alewife (Alosa pseudoharengus), spottail shiner (Notropis hudsonius), rainbow smelt (Osmerus mord iz), and bloater (Coregonus hoyi). Trawl catch of yellow perch, alewife, and spottail shiners at sites M, K, and G were strongly correlated suggesting similar fluctuations. Young-of-the-year trawl catch revealed that insight to population dynamics of species was not always reliable. Trawl CPUE of > age 1 fish provided insight to dynamics of the major species at all sample locations with strong trend similarities between sites. No strong major species interactions were found using simple linear correlations. / Department of Biology
3

An evaluation of the potential forage fish populations in Indiana waters of Lake Michigan, 1973 vs. 1984-86

McKeag, Kevin J. January 1987 (has links)
The potential near-shore forage fish populations were investigated by bottom trawling during the months of June through August of 1984-86 in Lake Michigan, near Michigan City, Indiana. Data were collected on the six moat common species including: yellow perch (Perca flavescens); alewife (Aloes pseudoharenqus); rainbow smelt(Osmerus mordax); bloater (Coreaonus,hovi); spottail shiner (Notroois hudsonius); and trout-perch (Perconsis omiscomavcus). Results of the 1984-86 sampling period were compared with data for 1973 in an attempt to document changes in population density, species composition, annual catch, seasonal abundance, and population structure.The total trawl catch for all species increased nearly seven-fold since 1973 even though sample methods and collection effort were unchanged. A dramatic increase in yellow perch abundance was primarily responsible for the elevated levels sampled for all species from 1984-86.The species composition of the catch shifted since 1973. In 1973, spottail shiners were the most abundant species (41%) and trout-perch and alewives were the next most abundant species comprising 20% and 17% of the catch, respectively. Yellow perch, which comprised only 12% of the catch in 1973, increased to 81% of the catch in 1986. Bloater also showed a great increase in relative importance since 1973 when they were rare in the catch. Other species, including alewife, were relatively minor components of the total catch each year from 1984-86. The trawl catch results revealed that alewife and trout-perch declined 71% and 87%, respectively, comparing 1973 with 1984-86. During the same period, yellow perch increased 72-fold and bloater over 3000-fold. By comparison, the spottail shiner population was stable with no long-term changes, but rainbow smelt populations fluctuated widely.Seasonal abundance of adult fish (age I or older) generally decreased from June to August for each fish species and year sampled with the exception of yellow perch which peaked in July of 1973, and in August of 1985-86. Young-of-the-year fish were generally captured in late July and August.Population structure changes were evaluated by examining pooled length-frequency data. Yellow perch length-frequency distributions indicated that strong year classes were produced every year from 1983 to 1986. The 1985 year class was well over twice as large as any of the other years sampled. Spottail shiner and rainbow smelt length-frequency distributions remained approximately stable since 1973, while alewife length-frequency distributions fluctuated annually. Capture of bloaters was almost entirely limited to June, and consisted primarily of age I+ fish in 1984-86.These results reveal significant changes have occurred in the potential near-shore forage fish populations in Indiana waters of Lake Michigan since the early 1970's. Although several factors may be involved in the shifts noted, the major contributing factor is likely predator-prey interactions as a result of salmonid predator density.
4

An analysis of the population dynamics of the yellow perch in Indiana waters of Lake Michigan

Stettner, Craig R. January 1989 (has links)
Age, growth, and abundance data were collected on yellow perch, Perca fla vescen, in Indiana waters of Lake Michigan in 1987 and 1988. The data collected were compared to data on yellow perch in Indiana waters of Lake Michigan dating back to 1975.Changes in growth, mortality, and abundance between 1975 and 1988 were clearly illustrated by the data. Growth has decreased; back-calculation indicates that "quality" (> 200 mm) perch in 1975 were about age II, however, "quality" perch in 1988 were over age V. Annual mortality values produced from following a cohort or comparing age classes indicate that mortality has decreased since 1981, most sharply in 1987 and 1988. Changes in growth and mortality are likely resultant of large changes in abundance. Indices of abundance (biomass and catch-per-uniteffort) reveal that the yellow perch population has become much more dense in the late 1980's than the 1970's and early 1980's. The percentage of quality perch has decreased, however, the abundance of quality perch has increased and peaked in 1988. / Department of Biology
5

Simulated forecasting of yellow perch (Perca flavescens) relative population density for Indiana waters of Lake Michigan : responses to varying harvest and alewife density

Cwalinski, Tim A. January 1996 (has links)
The yellow perch, (Perca flavescens), is an important commercial and sport fish in Indiana waters of Lake Michigan. The population is currently managed by temporary restrictions of commercial harvest. A computer simulation model was developed to examine the effects of various constant harvest quotas and alewife densities on yellow perch relative numbers.Model design is based on the SLAM II simulation language incorporating a FORTRAN biological subroutine. The age-structured population model includes measured or predicted biological characteristics of the dynamic pool model. Recruitment is based on a preestablished three-dimensional Ricker stock-recruitment function including alewife (Alosa pseudoharengus) species interaction as a constant or stochastic factor. Sex-specific natural mortality rates were established through life history parameter analysis and the von Bertalanffy growth factors. Density-dependent growth is incorporated into each year of a model run and fluctuates with the simultaneous density of fish. Constant levels of commercial harvest ranging from 0 to 700,000 kg were used in 20-year forecasts. Initial conditions for model runs were 1984 and 1994 trawl CPUE levels when yellow perch were at high and low levels, respectively according to standardized sampling. Response variables were examined as mean catches over each forecast length and included: age 2 fish, spawning stock (z 190 mm), and total catch > age 1.Alewife densities had a tremendous impact on mean catches of the response variables. Highest catches under any forecast period occurred when alewife was considered absent from the system. Catches declined as alewife density was increased as a 20-year constant under each harvest regimen.Catches of spawning size fish were maintained at highest levels for all forecast periods when harvest was set to zero. Catches of young fish were moderate with this harvest regimen if initial catch conditions were high such as in 1984. Catches of young fish were always higher in the absence of a commercial fishery if initial catch conditions were low such as in 1994. Low to moderate harvest quotas could maintain moderate levels of young fish for the forecast length if initial model conditions were high. However, these quota levels for the 1984-2004 forecast length resulted in lower mean catches of spawning size fish as compared to the no commercial fishery regimen. The best case scenario for all response variables when initial catch conditions were low was under a no commercial harvest regimen. / Department of Biology
6

The fish population of an east-central Indiana borrow pit lake with management implications

Brown, Forrest C. 03 June 2011 (has links)
The fish, invertebrate, and macrophyte communities of Dumpert's Lake, a borrow pit located in northwest Delaware County, Indiana were studied in 1979 and 1980. Data obtained from this study were used to evaluate the potential for quality fishing, to identify sport fish production problems, to assess largemouth bass food habits and habitat utilization, and to consider management options.Bluegill dominated the July and September, 1980 fish collections at 69 and 84 percent, respectively. The growth rates for age II and older bluegill indicated mortality rates above 55 percent. Stocklength (3 in., 76 mm) was.attained at annulus 2 and quality-length (6 in., 152 mm) was reached at age III+. The overall average annual growth increment was 48 mm (1.9 in.). Bluegill were in good condition by overall average K at capture (2.05) and at annulus formation (1.91). Corresponding mean Relative Weight (Wr) values were 106 and 107, respectively.Largemouth bass comprised 23 and 14 percent, respectively, of the July and September, 1980 fish collections. Bass attained stock-length (8 in., 200 mm) by age II+ and an additional 1.5-2.0 years (age III+ or older) was required to attain quality-length (12 in., 300 mm). Growth rates and length-frequency distribution verified mortality rates in excess of 60 percent for all age groups of stock-size bass. Average yearly growth was 70 mm (2.8 in.). Condition was poor by overall average K at capture (1.27) and at annulus formation (1.22). The overall mean Wr was 89 for the respective K values.A stock structure index, Proportional Stock Density (PSD), indicated an unbalanced largemouth bass and bluegill population. Bluegill PSD was 78 with largemouth bass PSD at 27.Radio telemetry observations for two largemouth bass monitored from late May to mid-July, 1980 indicated relative inactivity by observed displacement (98 and 366 m) with respective home ranges of 0.01 and 0.12 ha. Extensive use of shoreline cattails was noted at 79 and 84 percent of the respective locations. All observations were over lake depths of 0.5-0.9 m. Two bass tracked from late July to mid-September, 1980 were more active by displacement (1401 and 1429 m) with home ranges of 0.92 ha for both fish, and similar utilization of submergent pondweeds (46 and 50 percent, respectively). One bass was always observed over lake depths of 1.0 m or greater. The other bass was observed in shallow water (0.5-0.9 m) for 50 percent of the observations.Fish occurred more frequently (71 percent) in stomachs of largemouth bass ranging from 195-247 mm than in stomachs (11 percent) of bass 253-347 mm total length. Insects dominated the diet of the larger fish by percent in volume and weight (66 percent) compared to the smaller stock-size bass (21-22 percent). Odonata was the most frequent insect taxa in the diet of the smaller bass at 29 percent and Ephemeroptera was the dominant insect taxa (33 percent) in the diet of the larger fish.Epifaunal macroinvertebrates were more diverse by taxa compared to macroinvertebrates from three benthic habitats which were about equal in diversity by taxa. Zooplankton diversity by taxa was also similar among the benthic habitats. Macroinvertebrate density showed a trend of seasonal increase for the 1979 summer period, while distinct biomodal peaks for zooplankton abundance occurred in early July and late August, 1979 for vegetated and nonvegetated littoral zones.Najas flexilis, Potamogeton nodosus, and P. pusillus dominated the submergent macrophyte community in 1979. The overall mean seasonal dry weight biomass of macrophytes was 110 g/m2 (114 g/m3 ). Macrophyte control was recommended for improving the sport fishery.Ball State UniversityMuncie, IN 47306
7

Population analysis and food habits of the yellow perch, Perca flavescenes (Mitchill), in Indiana waters of Lake Michigan, 1984-86 / Population analysis and food habits of the yellow perch.

Gallinat, Michael P. 03 June 2011 (has links)
Yellow perch, Perca flavescens (Mitchill), were collected by trawling and gillnetting in Indiana waters of Lake Michigan near Michigan City, Indiana. Sampling was conducted during the months of June, July and August from 1984 through 1986.Growth rates and length-weight relationships were found to be considerably lower than those reported previously. Males declined 38 mm at age I, 55 mm at age II, 56 mm at age III and 35 mm at age IV comparing 1986 to 1976. Females showed similar declines for the same period at 40 mm for age I, 58 mm at age II, 66 mm at age III and 53 mm at age IV. The primary reason for the decrease in growth appears to be due to the current high population density of yellow perch in Indiana waters of Lake Michigan.Maturation of males for 1986 appears to be slower than that of 1984. All male perch were mature by age III in 1984. However, only 68x of the males were mature at the same age in 1986. In 1984, 94% of the females were mature by age IV while 86% were mature at the same age in 1986.Differences in maturation rate may be a reflection of the reduced growth rates. Size at maturity was found to be similar for both sexes in 1984 and 1986. All females were mature by 230-239 mm in 1984 and 220-229 mm in 1986. All male perch were mature at 180-189 mm in 1984 and 220-229 mm in 1986.Total estimated average annual percent mortalities of 79, 58, 66 and 55 were calculated for combined sexes from age composition analyses end trawl catch data for 1976 and 1984-86. Yellow perch production for 100 fish was estimated for June through August using the Allen curve method. Biomass of substock ( <130 mm), stock ( >129 mm) and quality fish (200 mm or larger) were estimated using Proportional Stock Density to investigate population structure. The Allen curve biomass models were modified to more accurately reflect the trawl catch density data as an index of population changes in 1976 compared to 1984-86. Theoretical biomass for the substock component increased 23 fold from 1976 to 1986. Biomass of the stock sized fish was estimated as 15 times greater in 1986 compared to 1976. Quality fish biomass varied from year to year with the average for 1984-86 estimated as 14 times greater than 1976. The most apparent factor now influencing deterioration of growth and resultant quality of the population is decreased mortality/increased survival with increase in biomass. If the low mortality rates observed for 1984-86 remain unchanged, the data indicate continued population density increases will result in even lower growth rates, and a population dominated by a higher percentage of small, non-quality fish.Food habit analyses for 1984 were compared to a diet study of yellow perch in 1972 for the study area. Zooplankton increased from 0.4x in 1972 to 9% of the volume in 1984 for 100-175 mm perch. This trend may reflect an increase in zooplankton populations in response to the population decline of the planktivorous alewife. Young-of-the-year yellow perch made up 85% of the stomach volume for 176-225 mm perch in 1984 while none were found in samples for 1972. This clearly shows yellow perch are resorting to cannibalism resulting from excessive intraspecific competition.Diet analyses by month revealed alewife eggs were moat important during peak abundance in June and July. Yellow perch (YOY) and Pontocoreia affinis became important during August. Analysis by size interval showed zooplankton and insects (primarily Chironomidae) were important to the diet of perch in the 30-59 mm (YOY) size interval. Copepoda were important by percent volume until approximately 60 mm when the zooplankton component switched to Cladocera. Data for 60-119 mm (age I+) fish indicates alewife eggs were important during June but insects became increasingly more important during July and August. Diversity in food items consumed diminished with increase in size as diet of 120-159 mm (age II+) yellow perch consisted largely of fish. Increases in percent volume of rainbow smelt in June and July, and Y0Y perch in August for age II+ and older perch compared to younger/smaller fish may be related to increased capture success. Diet of fish larger than 160 mm (age III+ and older) consisted almost entirely of rainbow smelt and Y0Y yellow perch.Ball State UniversityMuncie, IN 47306
8

Population structure and dynamics of alewives and spottail shiners in Indiana waters of Lake Michigan, 1984-1996

Tonello, Mark A. January 1997 (has links)
The population dynamics of alewives Alosa pseudoharengus and spottail shiners Notropis hudsonius were investigated in Indiana waters of Lake Michigan from 1984-1996. Insights to population dynamics of both species were found by applying age and growth information to length-frequency distributions of index trawl catches within and between years. Both alewife and spottail shiner populations showed general increasing trends over the period, reaching peak levels in 1996. Interaction potential was examined for alewives, spottail shiners, and the yellow perch Perca flavescens, another important nearshore species. Trends in relative catches of these species were correlated to provide insight to possible interactions. There appears to be negative relationships between alewife and yellow perch populations, as well as between yellow perch and spottail shiner populations. No relationships were found between alewife and spottail shiner populations. / Department of Biology
9

A computer simulation model for the yellow perch population in the Indiana waters of Lake Michigan

Allen, Paul J. January 2000 (has links)
A computer simulation model was developed to examine the effects of various levels of alewife densities, harvest, and bycatch rates on yellow perch Perca flavescens relative densities in Indiana waters of Lake Michigan. The model utilized STELLA® Research software to develop the age-structured population model to include measured or predicted biological characteristics of density-dependent growth, recruitment, and mortality.The model was validated by simulating historically documented yellow perch catch per unit effort (CPUE) from 1984 - 1998. A strong linear relationship (R2= 0.70) between the model predicted CPUE values and the actual CPUE values was found. Twenty year model projections were performed using 1998 yellow perch trawl CPUE as starting values. Alewife abundance was established as either constantly high, constantly low, or allowed to fluctuate randomly and forecasts made used the average of 100 runs. Harvest was imposed on the yellow perch population at 20, 40, and 60% rate levels for fish >_ 200 mm coupled with bycatch at20, 40 and 60% rate levels for fish ranging from 165 - 200 mm.Alewife abundance was the major factor determining the relative abundance of the yellow perch population. On average, constantly high alewife abundance with no harvest or bycatch resulted in projected continuing suppression of yellow perch abundance from 1998 levels. The model predicted the population to rebound using constant low and random alewife abundance with no harvest or bycatch to approximately 1,100 fish/h and 700 fish/h, respectively.The model revealed harvest to have a generally negative impact on the yellow perch population. Increasing harvest and bycatch rate levels resulted in the suppression of projected increases in yellow perch relative abundance. Additionally, increasing harvest and bycatch rates resulted in greater predicted declines in yellow perch abundance. / Department of Biology
10

Selected population characteristics of smallmouth bass and rock bass in a three county area of the West Fork of the White River, Indiana from 1991-1994

Foy, Joseph P. January 2000 (has links)
Several population characteristics were calculated for smallmouth bass Micropterus dolomieui and rock bass Ambloplites rupestris populations on the west fork of the White River in Randolph, Delaware, and Madison counties, Indiana and were compared to other populations. When compared to streams of similar size in Indiana that were sampled with the same methods, relative abundance (CPUE) of smallmouth bass was average (18.9-35.0 fish/hour) while rock bass were two to ten times more abundant (44.3-53.0 fish/hour). Age analysis and back calculation of length at age were only performed for smallmouth bass. These results indicated strong year classes were cyclical and smallmouth bass growth was above average for Indiana streams, but average for streams of the Midwest. Proportional stock density values were average for smallmouth bass (28-39%) and slightly below average for rock bass (17-33%). Strong weight-length models were also found for both species and relative weight values were optimal. / Department of Biology

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