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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

Movements of tagged yellow perch, Perca flavescens (Mitchell), in Indiana waters of Lake Michigan during 1980 and 1981

Meade, Richard January 1982 (has links)
During 1980 and 1981 respectively, 2425 and 4028 yellow perch 150-359 mm were Floy-tagged from June through August at four sites in Indiana waters of Lake Michigan. Most of the 6453 perch were tagged from mid-June to early August and almost 90% were less than 210 mm.An overall recapture rate of 3.2% (204 fish) was obtained by April 1, 1982. Site recapture rates were positively related to the numbers of fish tagged. Slightly over 92% of all fish were tagged at sites M and K and 94.5% of all recaptures originated from these two sites. Second season recaptures accounted for 25.5% of all recaptures. Peak recapture rates occurred in July. Sources of recaptures were 67.6% from sport fishermen, 25.5% from commercial fishermen, and 6.9% from Indiana Department of Natural Resources, Ball State University trawl catches and other sources.Most recaptured perch were in the 150-229 mm length interval, but an apparent size selection by both commercial and sport gear existed towards 180-229 mm perch. The recapture of large numbers of 150-159 mm fish indicated survival of small perch was not an important factor influencing size selection. Information on sizes of fish recaptured by sex and age was insufficient for evaluation.Although straight line movements of up to 166 km occurred, most fish remained near the original tagging sites. Distances traveled were similar for fish from all tagging sites in 1980, 1981 and for second season recaptures. Over 76% of all fish were recaptured in Indiana waters and about 86% traveled less than 32.0 km from the original tagging sites. The majority (64%) of fish leaving Indiana waters were captured nearby at New Buffalo and Union Pier, Michigan. About 68% of all recaptures were received within 60 days of release. Even though considerable variability was evident in the distances traveled with time, no seasonal trends were observed for perch of various sizes.Simple regression analysis of data for combined years revealed only 27% of all variation in distance traveled by perch was accounted for by the time at large (days) prior to recapture. Multiple regression analysis revealed the time at large was more important than fish length in relation to distance traveled, accounting for 27.3% and 0.2% of the explained variability, respectively. Data including second season recaptures more accurately represented these relationships and indicated these variables were poorly related to distance traveled. Examination of residuals showed a dramatic and statistically undesirable increase in unexplained variability was associated with far ranging fish. Other factors should be considered in future multiple regression analyses.Indiana yellow perch stocks appear to be fairly discrete entities. The majority of fish tended to remain periods of at least one year.
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 Lake Michigan alewife aging methodologies, growth, and stock separation

Labay, Steven R. January 2005 (has links)
Ageing methodologies of Lake Michigan alewife were evaluated as a precursor to growth and condition investigations of alewife stocks. Four commonly used aging tissues were evaluated including: otoliths, scales, vertebrae, and opercles. Otoliths were significantly more precise than other structures in all analyses. The accuracy of age determinations given by otoliths was corroborated through length frequency analysis. Total processing time was highest for scales. Whole otolith methodology was used to age alewives from Indiana, Michigan, and Wisconsin based on precision, accuracy, and time efficiency. A trend of higher median lengths and weights in young fish from the Green Bay, Wisconsin site was identified. Older fish grew faster in the main-lake sample sites near Pentwater, Michigan and Indiana waters. The Indiana population had the highest condition factor (K), while Wisconsin had the lowest, with Michigan in between. An overall temporal decline in condition of alewife was identified when compared with historical studies. This is a consideration that may influence salmonid stocking decisions because the alewife serves as their primary food. / Department of Biology
4

Fluctuating abundance of yellow perch and their relationship to growth in southern Lake Michigan, 1984-2004

Headley, Heath C. January 2006 (has links)
The relationship between yellow perch Perca flavescens abundance and growth rates were evaluated in the Indiana waters of Lake Michigan from 1984 to 2004. Relative abundance values were taken from trawl catch per unit effort (CPUE), while growth rates were determined by back-calculation. Abundance CPUE during the mid 1980's, was approximately one order of magnitude higher when compared to the 1990 to 2004 period. Growth rates were inversely related to relative abundance and were sexually dimorphic, with females growing faster than males. Regression analysis indicated approximately half of this observed variation in growth was due to abundance, and was most apparent with the smaller and younger fish. Both intraspecific competition and physiological changes associated with maturity are plausible explanations for the relationship. / Department of Biology
5

Population analysis of yellow perch, Perca flavescens (Mitchill), in Indiana waters of Lake Michigan

Asbury, Gregory E. 03 June 2011 (has links)
Yellow perch, Perca flavescens, were collected by trawling and gillnetting at 5m in a study area near Kintzele Ditch in Indiana waters of Lake Michigan. Sampling was conducted during the months of June, July and August in 1976 and 1977.Population characteristics were analyzed and compared to other studies. Growth rate and length-weight tended to be higher than in previous studies dealing with the Great Lakes, however, no specific reasons were identified. Growth differed between sexes, with females showing faster and more prolonged growth in older age fish. Significant overlap in ages I, II and III was apparent in both sexes, with growth differences evident between sexes of the same age. Virtually all (99%) age I male perch were mature, while only 15% age I females were mature. Approximately half of the age II females were mature with most age III females mature. Males were all mature at 150mm while females were all mature at 260mm.Sex ratios varied between samples, but were near unity for the combined sample period. No trends were apparent during the summer season for sex ratios in sex segregated populations.Catch-per-unit effort (CPE) remained relatively high during the entire sampling period. Lower CPE was noted with lower water temperatures. Sample variability was high throughout the sampling period, possibly due to gear selectivity, non-random distribution of individuals and repeated disturbances of the same area. When young-of-the-year were collected, their numbers were less variable than for older perch, a likely consequency of greater vulnerability to sample gear.The trawl tended to select for a wider range of sizes and greater total number of fish. The gill net consistently selected for larger fish. Neither method employed alone appeared capable of sampling the entire size range of fish.Differences in percent age in trawl and gill net samples were apparent with the gill net selecting for older fish. The trawl tended to sample a wide age range of fish.Comparison of data collected in Indiana and Michigan waters suggest fundamental differences in population structures. Indiana populations lacked significant numbers of larger, older fish which were adequately represented in samples from Michigan waters. Commercial harvest of perch in Indiana waters appears to be involved in the population structure differences.Ball State UniversityMuncie, IN 47306
6

Yellow perch Perca flavescens gonadal development and spawning in the Indiana portion of Lake Michigan during 2009

Walters, Justin T. 24 July 2010 (has links)
Yellow perch Perca flavescens spawning was evaluated in southern Lake Michigan during 2009 to determine the timing, location, and extent of spawning activity. Maturity state (i.e., pre-spawn/post-spawn), gonadosomatic index (GSI), mean length, length frequency distributions, and sex group proportions were also evaluated. No egg skeins were discovered during the study. The GSI decreased during the duration of the spawn. Spent females were larger than pre-spawn females. Following the spawning season another assessment was conducted to determine whether differences existed in the spawning and post-spawning population demographics. Abundance, length frequency distributions, proportions, and relative stock density were evaluated. Abundance of fish in the post-spawning period increased six-fold and paralleled a shift in length frequency distribution to larger median size. An increase in the proportion of females and relative stock density from the spawning period to post-spawning period was discovered. These data infer adult fish were spawning elsewhere, and then migrating to Indiana. / Department of Biology
7

Yellow perch, Perca flavescens, behavior in the Indiana waters of Lake Michigan in 2009, 2011 and 2012

Starzynski, David A. 20 July 2013 (has links)
The Indiana waters of Lake Michigan were sampled weekly from May until August in 2009, 2011, and 2012 to determine the extent of yellow perch reproduction and the role Indiana waters play in yellow perch life history. Experimental gill nets were used to collect fish before, during, and after the spawning season from randomly selected sites along the Indiana shoreline. Yellow perch were then taken to an onshore processing station where they were weighed, measured, and visually examined to determine sex and maturity. Maturity stages of adult yellow perch were used to estimate the timing and duration of yellow perch spawning. Yellow perch population demographics were also compared to determine if different groups of yellow perch were present before and after the spawn. My data suggests that yellow perch spawning is strongly influenced by temperature and that Indiana waters are seasonally used by adult yellow perch for feeding. / Department of Biology
8

Trawl and gill net selectivity of yellow perch in southern Lake Michigan, 1993-2006

Thomas, Nathan D. January 2007 (has links)
Selectivity of trawl and experimental gill nets was determined for yellow perch taken from southern Lake Michigan in 1993 to 2006. Gill nets were comprised of 51-, 64-and 76-mm size mesh and showed female modal lengths of 205-, 245-, and 295-mm, respectively, while values for males were 200-, 230-, and 267-mm. Differences between females and males increased with mesh size and was significant. Comparison of nine anterior morphometric features of female and male fish indicated no differences in shape were identified that would cause the disparity in selectivity. Rather, differences in male and female selectivity were more likely due the variant population size structure of the local population sampled, with females the larger sex. A new method to estimate trawl selectivity was developed using a modified catch-curve analysis, which showed a maximum selectivity length value (1.0) of 190-mm for females and 170-mm for males. However, trawls fail to capture larger yellow perch when compared to gill nets using based on length-frequency distributions. Revealing such gear biases may lead to more efficient capture methods, resulting in improved sampling and quantitative assessment of fish populations. / Department of Biology
9

The influence of abiotic factors on gill-net catch rates and the evaluation of mortality rates for yellow perch in southern Lake Michigan

Rydell, Joseph J. January 2008 (has links)
I determined differences in yellow perch gill-net catch-per-unit-effort (CPUE) at two depths (10 and 15 m) in the Indiana waters of Lake Michigan during June, July, and August from 1989 to 2006. I evaluated the abiotic factors of water temperature, water clarity, wave height, and wind direction to determine whether they influence the differences in yellow perch CPUE. This study suggests that yellow perch in southern Lake Michigan may select habitat based on water temperature during the summer, moving in response to thermocline changes. We also evaluated mortality rates for two distinct periods (1984-1994 and 2000-2007) in order to identify the response of the population to changes in exploitation. Yellow perch during 1984-1994 (high exploitation) and 2000-2007 (low exploitation) displayed an increase in mortality for fish of harvestable size. In addition, during 2000-2007 (low exploitation) we identified that female yellow perch reached exploitable size earlier in life than males. / Department of Biology
10

Comparison of gill-net and trawl catch of the inshore fish community in southern Lake Michigan / Comparison of gill net and trawl catch of the inshore fish community in southern Lake Michigan

Michaels, Samuel B. 24 July 2010 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / Department of Biology

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