Biomass of Freshwater Crustacean Zooplankton from Length–Weight Regressions

1985 ◽  
Vol 42 (8) ◽  
pp. 1380-1390 ◽  
Author(s):  
David A. Culver ◽  
Mary M. Boucherle ◽  
David J. Bean ◽  
James W. Fletcher
Keyword(s):  
Seasonal Variation ◽  
Body Length ◽  
Lake Erie ◽  
Lake Ontario ◽  
Dry Weight ◽  
Crustacean Zooplankton ◽  
Adult Males ◽  
Freshwater Crustacean ◽  
Males And Females

We present equations for calculating dry weight from body length for 14 common and widely distributed taxa of crustacean zooplankters; these were generated by regression from weights of individuals chosen from the range of lengths observed for each taxon, usually three replicate weights at each of five lengths. We include regressions for ovigerous and nonovigerous cladocerans, plus nauplii, early copepodites, and adult males and females for the copepods (30 length–weight relationships) and individual weights for given stages of copepods. We calculated the seasonal variation in crustacean biomass for a station in the Bay of Quinte, Lake Ontario, and for each of the three basins of Lake Erie. Biomass was dominated by Cladocera for both lakes, with Copepoda predominant in the spring. Mean individual dry weights varied seasonally for all taxa, confirming previous findings.

Zebra Mussels as Biomonitors for Organic Contaminants in the Lower Great Lakes

1996 ◽  
Vol 31 (2) ◽  
pp. 411-432 ◽  
Author(s):  
Michael E. Comba ◽  
Janice L. Metcalfe-Smith ◽  
Klaus L.E. Kaiser
Keyword(s):  
Great Lakes ◽  
Organic Contaminants ◽  
Lake Erie ◽  
Soft Tissues ◽  
Lake Ontario ◽  
Dry Weight ◽  
Zebra Mussels ◽  
Organic Contamination ◽  
Contamination Levels ◽  
St Lawrence River

Abstract Zebra mussels were collected from 24 sites in Lake Erie, Lake Ontario and the St. Lawrence River between 1990 and 1992. Composite samples of whole mussels (15 sites) or soft tissues (9 sites) were analyzed for residues of organochlo-rine pesticides and PCBs to evaluate zebra mussels as biomonitors for organic contaminants. Mussels from most sites contained measurable quantities of most of the analytes. Mean concentrations were (in ng/g, whole mussel dry weight basis) 154 ΣPCB, 8.4 ΣDDT, 3.5 Σchlordane, 3.4 Σaldrin, 1.4 ΣBHC, 1.0 Σendosulfan, 0.80 mirex and 0.40 Σchlorobenzene. Concentrations varied greatly between sites, i.e., from 22 to 497 ng/g for ΣPCB and from 0.08 to 11.6 ng/g for ΣBHC, an indication that mussels are sensitive to different levels of contamination. Levels of ΣPCB and Σendosulfan were highest in mussels from the St. Lawrence River, whereas mirex was highest in those from Lake Ontario. Overall, mussels from Lake Erie were the least contaminated. These observations agree well with the spatial contaminant trends shown by other biomoni-toring programs. PCB congener class profiles in zebra mussels are also typical for nearby industrial sources, e.g., mussels below an aluminum casting plant contained 55% di-, tri- and tetrachlorobiphenyls versus 31% in those upstream. We propose the use of zebra mussels as biomonitors of organic contamination in the Great Lakes.

Sex Ratios and Lengths of Adult Sea Lampreys (Petromyzon marinus) from a Lake Ontario Tributary

1974 ◽  
Vol 31 (1) ◽  
pp. 122-124 ◽  
Author(s):  
I. C. Potter ◽  
F. W. H. Beamish ◽  
B. G. H. Johnson
Keyword(s):  
Narrow Range ◽  
Sex Ratios ◽  
Petromyzon Marinus ◽  
Lake Ontario ◽  
Sea Lamprey ◽  
Adult Males ◽  
Sea Lampreys ◽  
Males And Females ◽  
The Mean ◽  
Humber River

The mean lengths of adult males and females of the sea lamprey (Petromyzon marinus) migrating into the Humber River from Lake Ontario in each of the years 1968–1972 varied little, and were similar to those found by other workers in recently established populations in the upper lakes. In contrast, the ratio of males to females, which lay within the narrow range of 1:1 to 1.26:1, was similar to those reported for long-established populations.

Occurrence and Seasonal Variation of Tributyltin in Marinas on Lake Ontario, Canada

2000 ◽  
Vol 35 (4) ◽  
pp. 681-692 ◽  
Author(s):  
Fan Yang ◽  
R. James Maguire
Keyword(s):  
Seasonal Variation ◽  
Surface Sediment ◽  
Reference Site ◽  
Lake Ontario ◽  
Dry Weight ◽  
Antifouling Agent ◽  
Survey Results ◽  
Butyltin Compounds ◽  
Dissolved Phase ◽  
Total Concentrations

Abstract A survey of five marinas and one reference site on Lake Ontario, Canada, was conducted to investigate the occurrence and variation of tributyltin (TBT) levels in water between April and December of 1998. The survey results revealed the presence as well as seasonal trends of TBT in these marinas. The TBT concentrations in water were found to coincide with boating activity. The level of TBT generally rose in summer when the boating activity was high, and the highest level of TBT found was 14 ng Sn/L. On average, 92% of the TBT was in the operationally defined “dissolved phase” in the waters analyzed. The butyltin compounds were also found in surface sediment and paint chips from some non-aluminum hulled pleasure boats, with total concentrations of butyltin species (including dibutyltin and monobutyltin) ranging from 59 to 570 ng Sn/g dry weight, and from 0 to 146 μg Sn/g, respectively. The results clearly indicated that TBT in the marina waters primarily originated from antifouling paint on pleasure boats, even though the use of TBT as an antifouling agent was regulated in 1989.

Somatic characteristics and reproduction of common vole, Microtus arvalis (Microtus arvalis

Biologia ◽  
2010 ◽  
Vol 65 (6) ◽  
Author(s):  
Ivan Baláž
Keyword(s):  
Sea Level ◽  
Body Length ◽  
Common Vole ◽  
Reproductive Season ◽  
Adult Males ◽  
Microtus Arvalis ◽  
Foot Length ◽  
Hind Foot ◽  
The Common ◽  
Males And Females

AbstractReproduction potential and biometry of somatic characteristics of the common vole Microtus arvalis were evaluated and discussed. The results were processed on the basis of an extensive material (2,171 individuals) from the whole territory of Slovakia (315 sites situated at altitudes from 100 to 1500 m above sea level). Among the somatic characteristics studied, the highest variability was found in body length and the smallest in hind foot length. Highly significant differences were also found between the foot length of adult males and females. Populations of M. arvalis at low altitudes were less numerous than at higher altitudes. Altitudinal differences in average embryo numbers in female uteri as well as differences in follicle length in males during the reproductive season were also observed.

Species identity and aqueous calcium concentrations as determinants of calcium concentrations of freshwater crustacean zooplankton

2006 ◽  
Vol 63 (5) ◽  
pp. 1007-1013 ◽  
Author(s):  
Adam Jeziorski ◽  
Norman D Yan
Keyword(s):  
Body Weight ◽  
Seasonal Variation ◽  
Important Determinant ◽  
Crustacean Zooplankton ◽  
Species Identity ◽  
Uptake Rates ◽  
Ca Uptake ◽  
History Of ◽  
Freshwater Crustacean ◽  
Positive Correlations

Calcium (Ca) is a major component of the crustacean zooplankton carapace. As crustacean zooplankton obtain most of their Ca from lake water, taxa with high Ca demands may be negatively affected if environmental Ca concentrations fall below thresholds necessary for adequate Ca uptake rates. Currently, Ca concentrations are falling in many soft-water lakes with a history of acid deposition, both within Canada and globally. Hence, there is a need to identify species with high Ca demands. We analyzed Ca concentrations of eight crustacean zooplankton taxa from nine lakes spanning a 0.4–35 mg·L–1 Ca gradient. Our objectives were to determine (i) if both species identity and lake Ca concentrations are determinants of zooplankton Ca concentration and (ii) if zooplankton Ca concentration varies seasonally. Large differences in Ca concentrations were observed among taxa. Levels in Daphnia sp. ranged from 2% to 8% of dry body weight, whereas levels in copepods and non-daphniid cladocera were much lower at 0.2%–0.4%. Seasonal variation in zooplankton Ca concentration was negligible, but positive correlations with lake Ca concentration were detected, with up to twofold differences in Ca concentration between lakes in three of the eight species. Species identity was the most important determinant of crustacean zooplankton Ca concentration.

Sexual dimorphism in the baiji, Lipotes vexillifer

1992 ◽  
Vol 70 (8) ◽  
pp. 1484-1493 ◽  
Author(s):  
Gao Anli ◽  
Zhou Kaiya
Keyword(s):  
Sexual Dimorphism ◽  
Body Length ◽  
Young Female ◽  
The Body ◽  
Analysis Of Covariance ◽  
Adult Males ◽  
Genital Aperture ◽  
Condylobasal Length ◽  
Males And Females ◽  
Width Measurements

Dimorphism was detected in body length and in skull dimensions of the baiji, Lipotes vexillifer. The age of a sample comprising 22 females and 14 males was estimated. A single-phase Laird growth model was fitted to the body length versus age data for females. Two curves were required for the males, one for those with 4 dentinal growth layer groups (GLGs) and another for those above that age, i.e., with more than 4 GLGs. Males and females have about the same growth rate until they have about 4 GLGs, after which males grow more slowly than females. Sexual dimorphism was also found in 9 external measurements, based on t-tests. Analysis of covariance showed that once the effect of body length was removed, only 1 of the 9 measurements, from the tip of the upper jaw to the genital aperture, differed significantly between males and females. Differences in skull measurements resulted mainly from an early slowdown in the rate of longitudinal growth of the male, before the increase in body length slowed. Females and males could be correctly sexed by discriminant analysis using the body length, condylobasal length, and zygomatic width, and also the condylobasal length, width of the rostrum at the base, and the zygomatic width, except for one young female. Eight skull length measurements were greater in adult females than in adult males after the effect of body length was removed, and five skull width measurements were greater in males when the effect of condylobasal length was removed. Asymmetry in the position of the blowhole and in skew of the skull is pronounced and is independent of body length and sex.

scholarly journals Toxicological Indices of Wistar Rats Fed Formulated Chaw of Telfairia occidentalis Planted on Crude Oil Contaminated and Remediated Soil

2022 ◽  
Vol 8 (2) ◽  
pp. 36-43
Author(s):  
Reginald C Ohiri ◽  
Eugene N Onyeike ◽  
Augustine A Uwakwe
Keyword(s):  
Crude Oil ◽  
Wistar Rats ◽  
Dry Weight ◽  
Adult Males ◽  
High Concentration ◽  
Telfairia Occidentalis ◽  
Polycyclic Aromatic ◽  
Males And Females ◽  
Viable Seeds ◽  
Serum Amylase Activity

Toxicological indices of wistar rats fed formulated chaw of Telfairia occidentalis planted on crude oil contaminated and bioremediated soil was studied. Farmland, measuring 18 m2 was divided into three lots of 4 m2 and 2 m space was allowed between each lot (A, B and C). Two lots were polluted, subjected to 16 weeks of bioremediation and viable seeds of T. occidentalis were planted and grown for 28 days. The harvested vegetable leaves were analyzed. Leaves from natural attenuated soil showed high concentration of both aliphatic and polycyclic aromatic hydrocarbons with values of 9.34+0.03 mg/kg and 9.18+0.05 mg/kg for C36 and Fluoranthene respectively, while the bioaugmented soil had Lead as the highest heavy metal with a value of 0.10+0.02 g/100g. Four groups, of 9 rats each (totalling 36 rats) of adult males and females, wealing males and females were subsequently sub-grouped into 3 and allowed to acclimatize for a period of 1 week. These animals were fed formulated rat chaw of 50% dry weight of T. occidentalis, from the three lots (control, bioaugmented and natural attenuated soil) for a period of 28 days. Assay of animals’ toxicological index showed elevated concentrations of alkaline phosphatase, alanine and aspartate aminotransferases, urea and creatinine in their sera. A slight increase in serum amylase activity was recorded, while concentrations of their haemoglobin and Packed Cell Volume (PCV) reduced. The obtained results from these biomarkers were confirmed by the histopathological sections of the animal organs.

Status and conservation of Mewari and Jaisalmeri camels in India

2007 ◽  
Vol 40 ◽  
pp. 87-101 ◽  
Author(s):  
S.C. Mehta ◽  
B. Bhardwaj ◽  
M.S. Sahani
Keyword(s):  
Body Length ◽  
Development Programme ◽  
Adult Males ◽  
Hilly Terrain ◽  
Livestock Species ◽  
The Status ◽  
Males And Females ◽  
Optimum Production ◽  
Average Adult

SummaryThe Mewari and Jaisalmeri breeds of camel are among the four major breeds of Indian camel. The Mewari breed is known for the production of milk and its adaptability to the hilly terrain of the Aravali hills in south Rajasthan whereas the Jaisalmeri breed is known for its riding and race potential. A total of 320 camels from 16 herds in eight villages belonging to three districts of the major breeding tract of the Mewari camel were covered. The population of the Mewari camel was estimated to be 16 221 heads with a 28% decline in the last five years. The extent of cross breeding was estimated to be 36%. The average adult Mewari camel had a 193 cm height at wither, 194 cm heart girth and 158 cm body length. Adult Mewari camels produce about 700 grams of hair per annum and the females produce 5–7 litres of milk per day. An integrated rotational grazing pasture development programme could be of great use in maintaining the Mewari camels with diverse livestock species under optimum production.To define the status of the Jaisalmeri camel, an investigation encompassing 1 760 camel breeders belonging to the 181 villages distributed over the entire strata of the tract was carried out. The population of the Jaisalmeri camel was estimated to be 118 083 heads with a 31% decline in the last five years. An adult Jaisalmeri camel had a 199 cm height at wither, 211 cm heart girth and 156 cm body length. Adult males and females weighed 593 and 519 kg, respectively. Emphasis should be placed on making the breedable males of the breed available throughout the strata and on improving the utility of the breed for in-situ maintenance of genetic diversity in the breed.

Seasonal Abundance of Crustacean Zooplankton and Net Plankton Biomass of Lakes Huron, Erie, and Ontario

1974 ◽  
Vol 31 (3) ◽  
pp. 309-317 ◽  
Author(s):  
N. H. F. Watson ◽  
G. F. Carpenter
Keyword(s):  
Lake Erie ◽  
Dry Weight ◽  
Lake Huron ◽  
Seasonal Abundance ◽  
Crustacean Zooplankton ◽  
Average Weight ◽  
Calanoid Copepods ◽  
Western Basin ◽  
Saginaw Bay ◽  
Western Lake

Crustacean zooplankton concentrations (numbers per m3) in the upper 50 m found in lakewide cruises during all or most of the seasons on lakes Ontario and Erie in 1970 and on Lake Huron in 1971 showed that the species of zooplankton crustaceans present in the three lakes were generally identical, although the times of maxima and relative species compositions differed. Calanoid copepods were most abundant and diverse in Lake Huron and western Lake Erie. Cyclopoids and cladocerans were most abundant in lakes Erie and Ontario and in the Saginaw Bay region of Lake Huron. The most abundant cyclopoid throughout the year in all three lakes was Diacyclops bicuspidatus thomasi; Tropocyclops prasinus and Acanthocyclops vernalis were abundant especially in lakes Ontario and Erie, respectively. Cladocerans were most numerous in lakes Erie and Ontario. Numbers of individuals fluctuated markedly through the season with maxima in the spring or summer months in all three lakes.Biomass values (ash-free dry weight) were highest in Lake Erie, especially the Western Basin, and in Saginaw Bay of Lake Huron. Although numbers of crustaceans/m3 were much lower in Lake Huron than in Lake Ontario, net biomass values were similar. This was due to the greater size and average weight of crustaceans in Lake Huron samples. Inshore waters of lakes Ontario and Huron and all three basins of Lake Erie were subject to greater fluctuations in concentrations of crustacean zooplankton and net biomass values than in the pelagic waters of lakes Ontario and Huron.

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping data

2010 ◽  
Vol 27 (2) ◽  
pp. 85-91 ◽  
Author(s):  
Martin Šlachta ◽  
Jan Frelich ◽  
Tomáš Tonka
Keyword(s):  
Seasonal Variation ◽  
Spatial Variation ◽  
Dry Weight ◽  
Seasonal Distribution ◽  
The Other ◽  
Pitfall Trapping ◽  
Other Hand ◽  
Nested Anova ◽  
Species Groups ◽  
Dung Decomposition

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping dataAn analysis of data on the dry weight biomass of coprophagous beetles in standardized dung (4.5 l) was conducted in order to characterize the spatial and the seasonal distribution of the beetles' biomass in cattle pastures and to elucidate their function in dung decomposition. Nested Anova with factors of farm, site (nested in farm), seasonal period and year was used to evaluate the effect of these factors on the biomass of four functional species groups: the dung dwellers ofScarabaeidae(subfamilyAphodiinae), the dung dwellers ofHydrophilidae, the small tunnellers ofScarabaeidae(subfamilyCoprinae) and the large tunnellers ofGeotrupidae. The spatial variation of biomass (between the sites and the farms) was insignificant (P>0.05) in the two dung-dweller groups and in the large-tunnellers group. On the other hand, a significant (P<0.05) seasonal variation of biomass was found in all but the large tunneller group. In dung dwellers, the spring biomass was formed mainly by two species,Aphodius prodromusandA. sphacelatus. In summer, most of the biomass was accounted for bySphaeridium lunatum, S. scarabaeoidesandA. rufipes. In the two tunneller groups,Onthophagus fracticornis, Geotrupes stercorariusandG. spinigerformed a majority of the biomass in dung.

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