Maturity and Fecundity of Walleyes from the Eastern and Western Basins of Lake Erie

1969 ◽  
Vol 26 (7) ◽  
pp. 1877-1888 ◽  
Author(s):  
David R. Wolfert
Keyword(s):  
Lake Erie ◽  
The Other ◽  
Western Basin ◽  
Eastern Basin ◽  
Total Length ◽  
Younger Age ◽  
Mean Diameter ◽  
The Mean ◽  
Egg Diameter ◽  
Accurate Indicator

Of 2427 walleyes (Stizostedion vitreum vitreum (Mitchill)) examined from Lake Erie in 1964–66, no females were mature at ages below III and all were mature at age V. All male walleyes from the eastern basin were mature at age II, and those from the western basin at age III. Females from the western basin matured at a shorter length and a younger age than those from the eastern basin. Males from the western basin, on the other hand, matured at a longer length and greater age than those from the eastern basin.Egg production, which was estimated for 60 walleyes from the eastern basin and 78 from the western basin, ranged from 48,000 to 614,000. The number of eggs increased rapidly with increase in total length, but the relation between fecundity and weight was almost linear. Walleyes from the western basin were much more fecund for any given length, weight, or age than those from the eastern basin. Weight was the most accurate indicator of fecundity. The mean diameter of eggs from 32 ripe walleyes was 1.72 mm. Little relation existed between egg diameter and length or age of fish.

scholarly journals Does behavioural thermoregulation underlie seasonal movements in Lake Erie walleye?

2018 ◽  
Vol 75 (3) ◽  
pp. 488-496 ◽  
Author(s):  
Graham D. Raby ◽  
Christopher S. Vandergoot ◽  
Todd A. Hayden ◽  
Matthew D. Faust ◽  
Richard T. Kraus ◽  
...  
Keyword(s):  
Lake Erie ◽  
Seasonal Migration ◽  
Central Basin ◽  
Behavioural Thermoregulation ◽  
Long Distance ◽  
Western Basin ◽  
Eastern Basin ◽  
Temperature Records ◽  
Thermal Preferences

Thermoregulation is presumed to be a widespread determinant of behaviour in fishes, but has not often been investigated as a mechanism shaping long-distance migrations. We used acoustic telemetry and animal-borne thermal loggers to test the hypothesis that seasonal migration in adult walleye (Sander vitreus) in Lake Erie is size- and (or) sex-specific and related to behavioural thermoregulation. Female walleye migrated out of the warm, shallow western basin earlier than did males and were 1.8 times more likely to be detected on acoustic receivers in the deeper and cooler eastern basin. The few fish that remained in the western basin were restricted to a smaller range of higher temperatures (≥20 °C) than those that migrated to the central and eastern basins (∼16–21 °C). However, temperature records from walleye in the central basin were nearly indistinguishable from those in the eastern basin, suggesting thermal preferences alone could not explain migration to the eastern basin. As such, our effort to understand the mechanisms that cause migratory behaviours has generated mixed evidence on the role of temperature and that factors like foraging opportunities may have synergistic roles in the migration.

Seasonal Distribution, Constitution, and Abundance of Zooplankton in Lake Erie

1969 ◽  
Vol 26 (9) ◽  
pp. 2459-2476 ◽  
Author(s):  
Charles C. Davis
Keyword(s):  
Chlorophyll A ◽  
Lake Erie ◽  
Seasonal Distribution ◽  
Severe Weather ◽  
The Other ◽  
Western Basin ◽  
Lake Morphology ◽  
Similar Series ◽  
Ice Conditions ◽  
Work Done

Zooplankton samples, collected by vertical hauls from near bottom to the surface, were obtained from 28 stations along the length of Lake Erie in October 1967. A partial similar series, confined largely to the Western Basin because of ice conditions, was collected in January 1968. The results of the analyses are tabulated as numbers of individuals per m3, and are discussed. Comparisons are made with results previously published for a comparable series of stations visited in July 1967.As in July, distinct differences were to be seen among the three major basins (Western, Central, and Eastern) in the October results. These differences are summarized. In July an expected decrease in zooplankton, such as would be predicted from lake morphology, amount of runoff from rivers, etc., occurred from west to east in the lake. In October, however, the zooplankton of the Western Basin was extremely impoverished, and the expected distribution of biomass was reversed. It is shown, on the other hand, from work done by others on samples taken from the same series of stations in October, that phytoplankton, chlorophyll a, and seston exhibited the expected distribution, emphasizing the danger of judging an ecosystem by the examination of only limited components of the community and at single periods of the year.In July the bulk of the zooplankters consisted of large cladocerans (especially daphnids) and copepods. In October there were much larger populations of rotifers and of small cladocerans (Bosmina, Chydorus). Copepods were relatively sparse. The January samples were characterized by greater numbers and a greater variety of diaptomids than in October, and the rotifers remained very important. All of the January samples contained many partially decayed microcrustaceans. This was interpreted as indicating a seasonal die-off associated with the very severe weather of the period.

An explorative study into the possible benefits of using humor in creative tasks with a class of primary five pupils

2014 ◽  
Vol 27 (2) ◽  
Author(s):  
Felicity Boyle ◽  
Niamh Stack
Keyword(s):  
Creative Thinking ◽  
The Other ◽  
Future Research ◽  
Spoken Dialogue ◽  
Explorative Study ◽  
Younger Age ◽  
Potential Benefits ◽  
The Mean ◽  
Creative Tasks ◽  
Modern Workplace

AbstractCreativity now occupies a legitimate place in the curriculum of U.K. schools. Research on the benefits of creativity and an acute awareness of its necessity in the modern workplace have both served to raise its profile. A number of researchers have investigated factors which are most likely to enhance creativity. Ziv (1983) in particular, has researched how humor can be used to promote creativity in adolescents. This study investigates the potential benefits of introducing humor before tasks which require a creative output from pupils of a younger age. The experiment tested the hypothesis that exposure to humorous stimuli in the form of a film cartoon would improve children's subsequent creativity scores in the Torrance Tests of Creative Thinking (2006). One group observed animated cartoons with humorous spoken dialogue while the other group observed animated cartoons without humorous content before test booklets were administered. The mean overall creativity score in the humorous condition (M = 59.43, SD = 13.11) was lower than the mean for the non-humorous condition (M = 67.00, SD = 8.98). Possible explanations for the results and directions for future research in this relatively new field, exploring the use of humor within education, are discussed.

A Phosphorus Budget for Lake Erie

1976 ◽  
Vol 33 (3) ◽  
pp. 564-573 ◽  
Author(s):  
N. M. Burns ◽  
J. D. H. Williams ◽  
J.-M. Jaquet ◽  
A. L. W. Kemp ◽  
D. C. L. Lam
Keyword(s):  
Total Phosphorus ◽  
Lake Erie ◽  
Central Basin ◽  
Phosphorus Retention ◽  
Western Basin ◽  
Eastern Basin ◽  
Phosphorus Budget ◽  
Natural Origin ◽  
Lake Bottom ◽  
Entire Lake

A budget for phosphorus retention in Lake Erie during 1970 has been drawn up. Phosphorus associated with sand-sized particles (> 63 μm) was excluded. Retention of apatite phosphorus (AP) and nonapatite phosphorus (NAP) within each of the three basins of the lake (Western, Central, and Eastern) was estimated in each case by two independent methods. The two estimates of retention of total phosphorus within the entire lake agreed to within 9.5% of their mean. The estimates of AP retention within the Western basin also agreed well. However, the input–output balance estimates of AP retention in the Central basin and of NAP retention in the Western and Central basins greatly exceeded the corresponding sedimentation values, while in the Eastern basin this pattern was reversed. The AP discrepancy was attributed to unobserved transport of AP from the Central to the Eastern basin via nearshore currents past Long Point, while the NAP discrepancies were largely attributed to eastward movement of NAP through the lake within about 2 m of the lake bottom. The total amount of phosphorus retained within the lake in 1970 was 41,000 metric tons, or about 92% of input. AP of natural origin and inert nature accounted for approximately 44% of the total phosphorus retained. A reduction in anthropogenic phosphorus input of about 15,000 metric tons/yr, as called for in the Great Lakes Water Quality Agreement, will reduce present annual NAP loading to close to pre-1850 values.

scholarly journals Fertilization and development of bovine oocytes grown in female SCID mice

Zygote ◽  
2005 ◽  
Vol 13 (4) ◽  
pp. 309-315 ◽  
Author(s):  
Shoichiro Senbon ◽  
Kyosuke Ishii ◽  
Yoshiyuki Fukumi ◽  
Takashi Miyano
Keyword(s):  
Chorionic Gonadotropin ◽  
Blastocyst Stage ◽  
Scid Mice ◽  
The Other ◽  
Cell Stage ◽  
Mean Diameter ◽  
Bovine Spermatozoa ◽  
The Mean ◽  
Equine Chorionic Gonadotropin ◽  
Bovine Oocytes

We previously reported that xenografted bovine secondary follicles developed to the antral stage in severe combined immunodeficient (SCID) mice. In the present study, bovine secondary follicles 100–240 μm in diameter were xenografted under the kidney capsules of female SCID mice for 6 and 8 weeks, and we examined the oocytes' fertilization and developmental abilities. Bovine follicles developed with prolongation of grafting and became significantly larger than those before grafting. Injection of equine chorionic gonadotropin (eCG) into host mice made some surviving follicles develop larger than the other follicles. Furthermore, bovine oocytes grew in the follicles, and the mean diameter of the oocytes was 100 μm or more at 6 and 8 weeks of transplantation. Bovine oocytes that had grown in eCG-stimulated SCID mice 8 weeks after grafting were subjected to maturation culture. Some of the oocytes that had grown to 110 μm or more matured to the second metaphase (7% of oocytes 110–119 μm and 44% of those >120 μm). When the oocytes were inseminated with bovine spermatozoa, 15% (6/39) formed a female and a male pronucleus, and 2 days after insemination 24% (18/75) of oocytes cleaved and 2% (2/75) developed to the 5- to 8-cell stage. However, no embryo reached the blastocyst stage. These results indicate that bovine oocytes grown in SCID mice could be fertilized but acquired insufficient competence for embryonic development in the present conditions.

Primary Production in Lakes Ontario and Erie: A Comparative Study

1974 ◽  
Vol 31 (3) ◽  
pp. 253-263 ◽  
Author(s):  
Walter A. Glooschenko ◽  
James E. Moore ◽  
Mohiuddin Munawar ◽  
R. A. Vollenweider
Keyword(s):  
Primary Production ◽  
Chlorophyll A ◽  
Lake Erie ◽  
Lake Ontario ◽  
Early Summer ◽  
Central Basin ◽  
Western Basin ◽  
Eastern Basin ◽  
Production Values ◽  
Rate Of Increase

Primary production values in Lake Ontario were low in winter, reached a maximum in midspring, declined during summer, and slightly increased in fall. Rate of increase of production for inshore waters (< 20 m depth) was greater especially in spring and early summer with a greater maximum reached earlier than in offshore waters. Assimilation numbers, mgC fixed/mg chlorophyll a per hour, in Lake Ontario were fairly constant over the lake with a yearly range of 1.2–1.6. Primary production showed a linear relationship to chlorophyll a concentration, as also occurred in Lake Erie.Lake Erie primary production varied in its three basins. Seasonally, in the Eastern Basin, production was highest in spring with a midsummer decline, and small peaks in fall. The Western Basin had a maximum in midsummer whereas the Central Basin had peaks in late summer and early fall. Assimilation numbers were highest in the Western Basin (up to 3.5 mgC/mg chlorophyll a per hour) and lowest in the mid-Central Basin and Eastern Basin with values of approximately 1.4 mgC/mg chlorophyll a per hour. A definite westerly increase of assimilation number was observed.Up to early summer, the two lakes were fairly equal in surface production but integral photosynthesis, mgC/m2 per hour was higher in Lake Ontario than in Lake Erie. The same was valid in November and December. In summer, Lake Erie was higher in production on both a mgC/m3 per hour and mgC/m2 per hour basis. For the period, April–December, Lake Ontario's total estimated yield was 170 gC/m2, whereas for Lake Erie values of 160, 210, and 310 gC/m2 were found for the Eastern, Central, and Western basins, respectively.

scholarly journals ECOSYSTEMS STATE OF EASTERN AND WESTERN BASINS OF SAKSKOE LAKE (CRIMEAN REPUBLIC)

2021 ◽  
Vol 7 (73) (1) ◽  
pp. 218-228
Author(s):  
V. V. Chaban ◽  
I. I. Rudneva ◽  
N. V., Guskova ◽  
V. G. Shaida
Keyword(s):  
Total Content ◽  
The Other ◽  
Water Bodies ◽  
Lake Ecosystem ◽  
Western Basin ◽  
Eastern Basin ◽  
Building Activity ◽  
Anthropogenic Processes ◽  
Basin Brine ◽  
Resources Exploitation

Sakskoe Lake is the most thoroughly studied water body in Crimea. Its therapeutic mud and brine are exploited by balneological treatment methods. During the two centuries, when the lake was used by humans, it was subdivided into seven water bodies by dams, with two of these bodies (Eastern and Western) being now utilized for medical purposes, and the other five being protective. The Eastern (currently exploited) basin is now used to produce therapeutic mud and brine. The bottoms of the saline basins are covered by sediments: an upper layer of black silt, which is underlain by gray, steel-gray, occasionally bluish silt, which is used as therapeutic mud. The lake is fed by surface and groundwaters. Retaining dams and flood embankments erected in nearby ravines preclude desalination of the lake with flood and rain waters. Seawater is pumped to the lake through channels to preclude its drying. A quay is now actively constructed around the lake and will likely notably affect its hydrological and ecological conditions. The aim of the present study was the comparative analysis of the chemical and physical characteristics of the Eastern and Western basins of the Sakskoe Lake at the period of intensive building activity on their coasts at the summer period of 2019. Brine samples were collected at two tested sites in each of the lakes. Water salinity was measured by a PAL-06S LTA GO (Japan) refractometer and was expressed in ‰. The pH and Eh of the waters and oxygen dissolved in them were determined in the laboratory by an Expert-001 (Econix-Expert Moexa CoLtd, Russia) analyzer, with the use of appropriate Volta (Russia) selective electrodes. Ions concentration was determined spectrophotometrically and by atomic absorption method. Various living stages of Artemia populations in two water bodies were studied according the standard microscopic methods. The obtained results demonstrated, that the total content of the cations in the brine of the Western basin was in 1,5-fold higher as compared with the data of the brine in the Eastern basin (108,4 and 71,2 g/l respectively). The values were directly correlated with the high salinity of the Western basin brine. The identical trend was shown for the anions concentration, which was significantly greatly in the Western basin related to Eastern one (193,14 and 125,41 g/l correspondingly), which was connected with the different hydrogeological conditions of the formation of the ecosystems of the tested water bodies. At the other hand, pH, salinity and Eh of the brine in the Eastern basin were lower than in the brine of the Western basin, while the concentration of dissolved oxygen was higher. In the brine of the Eastern basin of the lake all living stages of Artemia, including cysts, nauplia and adults were found, while in the Western basin only cysts were shown. Therefore, according the obtained results we could suggest, that anthropogenic processes which were taken place on the coasts of the Sakskoe Lake accompanied with the intensive building activity did not influence on the lake ecosystem. The further monitoring studies including the testing of the ions concentrations in the brine of two basins, Artemia populations state are required for the understanding the changes of the both ecosystems and the possible reasons of their changes. It is important for development of the optimization of the management of Sakskoe lake and its resources exploitation.

scholarly journals Kültür Koşullarında Astacus leptodactylus (Eschscholtz, 1823)'un Yumurta Verimliliğinin Belirlenmesi

2019 ◽  
Vol 7 (4) ◽  
pp. 646
Author(s):  
Gülşen Uzun Gören ◽  
Sedat Karayücel ◽  
Birol Baki
Keyword(s):  
Negative Relationship ◽  
Live Weight ◽  
Strong Relationship ◽  
Culture Conditions ◽  
Total Weight ◽  
Astacus Leptodactylus ◽  
Total Length ◽  
The Mean ◽  
Egg Diameter ◽  
The Relationship

In this study, it was aimed to determine there and fecundity by adapting crayfish (Astacus leptodactylus) obtained from Bafra Fish Lakes (Ulugöl-Samsun) in culture conditions. Crayfish obtained in November 2016 were stocked in tanks and egg and morphometric characteristics of female crayfish with carrying eggs were determined. Correlation analysis were used for the relationship between the determined parameters. The mean total weight and total length of crayfish were 41.79±3.00g, 10.72±0.22cm, respectively whereas the mean number and diameter of eggs were 156.40±33.24 and 2.50±0.12mm. There were positive strong relationship between total length and total weight of crayfish negative relationship was found between egg diameter and total number of eggs, egg diameter and total weight of eggs and egg diameter and number of eggs for per unit of live weight.

A Lakewide Study of Phytoplankton Biomass and its Species Composition in Lake Erie, April–December 1970

1976 ◽  
Vol 33 (3) ◽  
pp. 581-600 ◽  
Author(s):  
Mohiuddin Munawar ◽  
Iftekhar F. Munawar
Keyword(s):  
Phytoplankton Biomass ◽  
Lake Erie ◽  
Biomass Concentration ◽  
Horizontal Distribution ◽  
Size Analysis ◽  
Central Basin ◽  
Western Basin ◽  
Eastern Basin ◽  
Ceratium Hirundinella ◽  
Wide Range

Surface samples of phytoplankton were collected from April to December 1970 at approximately 4-wk intervals from 25 stations distributed over the entire lake. Taxonomic identification and enumeration was done by the Utermöhl technique. About 125–150 species were identified in each basin. "Less common" or rare species contributed significantly to the total phytoplankton biomass. The species comparison among the three basins indicated that species like Rhodomonas minuta and Cryptomonas erosa were perennial in all the basins. Aphanizomenon flos-aquae, Anabaena spiroides var. contracta, Coscinodiscus rothii, Actinastrum hantzschii, and Ceratium hirundinella were typical for the Western basin. Ochromonas spp. and Peridinium aciculiferum were common in the Central basin whereas Gymnodinium helveticum and G. uberrimum were characteristic for the Eastern basin.The diatoms contributed least in the Eastern basin (36%) but showed high percentage in both Central (55%) and Western (58%) basins. The phytoflagellates made important contributions in the three basins; highest percentage (41%) was in the Eastern basin. Phytoflagellate abundance increased from west to east and appeared to have a wide range of adaptability to different nutrient conditions. During July and August high biomass concentration but uneven horizontal distribution was observed. Phytoplankton biomass ranged between 0.8 and 13.2, 0.6 and 6.0, and 1.0 and 4.2 g/m3 in the Western, Central, and Eastern basins, respectively. The highest biomass of 13.2 g/m3 was in the Western basin during April. Inshore–offshore differentiation was observed in the Central and Eastern basins with many peaks in the inshore region. Size analysis of phytoplankton on a few stations showed that the nannoplankton [Formula: see text] comprised a major portion of phytoplankton biomass during spring and fall periods. Based on maximum biomass concentration the Lake Erie Western basin was classified as highly eutrophic, the Eastern basin as mesotrophic, and the Central basin between the mesotrophic and eutrophic conditions.

Mercury in the Surficial Sediments of Lake Erie

1976 ◽  
Vol 33 (3) ◽  
pp. 404-412 ◽  
Author(s):  
R. L. Thomas ◽  
J.-M. Jaquet
Keyword(s):  
New York ◽  
Lake Erie ◽  
Total Mercury ◽  
Central Basin ◽  
Surficial Sediments ◽  
Western Basin ◽  
Eastern Basin ◽  
Detroit River ◽  
Mercury Cell ◽  
Mercury Loading

In 259 samples of the topmost 3 cm of sediment taken from Lake Erie in 1971, total mercury values ranged from 8 to 2929 ppb [Formula: see text]. The highest levels were in the Western basin adjacent to the Detroit River, the rest of the lake showing increasing concentration from the coarser sediments of the Inshore Zone and cross-lake moraine sills out into the basin muds. A quartz correction was applied to compensate for texture and dilution by an inert constituent. The distribution of quartz-corrected mercury confirmed that the Detroit River is the predominant source of industrial mercury to the Western basin with subsequent transport across the Central basin to final sink in the Eastern basin. Further possible inputs were indicated from Erie, Pennsylvania and Buffalo, New York. Analysis of suspended sediment in the Detroit River showed no change in concentration between 1970 and 1974 with a mean 1974 level of 1060 ppb. Mercury loading was estimated at 7.2 m.t./yr to the sediments of the Western basin. A relationship was observed between total mercury and organic carbon, showing two distinct regressions: ’A’ with lower organic-bound mercury, is taken to represent the levels related to industrial and natural loadings existing prior to the introduction of mercury cell chlor-alkali plants; ’B’ applicable to highly contaminated sediments, is believed to be indicative of loadings derived from the chlor-alkali industry.

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