Mysis diluviana population and cohort dynamics in Lake Ontario before and after the establishment of Dreissena spp., Cercopagis pengoi, and Bythotrephes longimanus

2011 ◽  
Vol 68 (5) ◽  
pp. 795-811 ◽  
Author(s):  
Ora E. Johannsson ◽  
Kelly L. Bowen ◽  
Kristen T. Holeck ◽  
Maureen G. Walsh
Keyword(s):  
Gravid Female ◽  
Food Resource ◽  
Fish Predation ◽  
Mortality Rates ◽  
Zooplankton Biomass ◽  
Bythotrephes Longimanus ◽  
Lake Productivity ◽  
Cercopagis Pengoi ◽  
Before And After ◽  
Food Concentrations

We investigated population responses of Mysis to ecosystem changes induced by invasion of dreissenids and predatory cladocerans, Cercopagis and Bythotrephes . Lake productivity declined as dreissenids invaded the offshore region. Whole-lake mysid biomass was compared before (early 1990s) and after (2002–2007) the invasion period; it declined 40%–45%. Abundance of young mysids and presence of a summer cohort increased with summer, epilmnetic, nighttime zooplankton biomass (i.e., food biomass index). Cercopagis + Bythotrephes biomass was negatively correlated with this index, implicating them in the mysid decline. Eggs per gravid female increased with autumn, total-water-column zooplankton biomass, reflecting the greater use of hypolimnetic waters by adults. Reproductive success was below replacement during the period 2002–2005. First-year mysid growth rate was maintained while population abundance declined, suggesting selection for individuals that feed effectively at low food concentrations. Mortality rates in the first and second years were dependent on cohort density, indicating that competition for food limited abundance in the first 2 years. Fish predation indices (smelt and alewife combined) were correlated positively with mortality rates and negatively with abundance in the third year. Thus, mysids cannot support as many fish in invaded compared with non-invaded lakes. They may also not be a stable food resource; unusual cohort losses occurred in some years.

Replacement of herbivore zooplankton species along gradients of ecosystem productivity and fish predation pressure

1995 ◽  
Vol 52 (4) ◽  
pp. 733-742 ◽  
Author(s):  
Dag O. Hessen ◽  
Tom Andersen ◽  
Bjørn A. Faafeng
Keyword(s):  
Fish Community ◽  
Zooplankton Community ◽  
Fish Predation ◽  
Zooplankton Biomass ◽  
Predation Pressure ◽  
Lake Productivity ◽  
Herbivorous Species ◽  
Main Determinants ◽  
Average Size ◽  
Zooplankton Communities

In general the pooling of major taxa did not provide a basis for classifying zooplankton communities in 342 large Norwegian lakes, as neither cladocerans nor calanoids varied systematically with lake productivity or fish predation pressure. At the species level, most herbivorous cladocerans and calanoids, which constituted three quarters of the metazoan zooplankton biomass, differed in their preference for lake productivity and fish community and could be distinctly grouped according to these variables by canonical correspondance analysis. The analysis pointed out one oligotrophic and one eutrophic specialist among the herbivorous cladocerans, while two of the calanoids were oligotrophic specialists. The biomasses of cladocerans, calanoids, or daphnids were poorly correlated with both lake productivity and fish predation, whereas shifts in average size and species distribution could be attributed to these variables. At low lake productivity, chemical variables such as pH and Ca, as well as the species' physiological adaptations, appear as the main determinants for the competitive advantage and relative success of herbivorous species. Fish community composition changes with increasing lake productivity, but only at very high fish predation intensity (cyprinid communities) did the effects of predation become the main determinant of the zooplankton community, superimposed on the lake productivity.

scholarly journals Impact of the 2017 Child and Adult Care Food Program Meal Pattern Requirement Change on Menu Quality in Tribal Early Care Environments: The Food Resource Equity and Sustainability for Health Study

2019 ◽  
Vol 4 (Supplement_1) ◽  
pp. 12-22 ◽  
Author(s):  
Susan B Sisson ◽  
Kaysha Sleet ◽  
Rachel Rickman ◽  
Charlotte Love ◽  
Alexandria Bledsoe ◽  
...  
Keyword(s):  
Native American ◽  
Best Practice ◽  
Food Resource ◽  
Saturated Fat ◽  
Health Study ◽  
Healthy Weight ◽  
Early Care ◽  
Adult Care ◽  
Nutrient Analysis ◽  
Before And After

ABSTRACT Background Native American (NA) children have a high prevalence of obesity contributing to lifespan health disparities. Dietary intake is important to promote healthy weight gain, growth, and development. In 2017, the USDA enforced changes to the Child and Adult Care Food Program (CACFP). The CACFP provides reimbursement to qualifying Early Care and Education (ECE) programs that serve foods that uphold the program's nutrition requirements. Objective This study had the following 2 objectives: 1) Describe a novel index to evaluate ECE menus based on revised CACFP requirements (accounting for food substitutions) and best practices for 3- to-5-y-old children, and 2) analyze CACFP requirement and best practice compliance and nutrient changes in 9 NA ECE programs before and after enforcement of the revised CACFP requirements. Methods This longitudinal study is within a larger community-based participatory research study. Menus and meals served were evaluated for 1 wk at each of 9 programs before and after enforcement of the revised meal patterns. Nutrient analysis, CACFP requirement and best practice compliance, and substitution quality were evaluated. Differences were determined using a paired t-test or Wilcoxon matched test. This trial was registered at clinicaltrials.gov as NCT03251950. Results Total grams of fiber consumed increased (5.0 ± 1.2 compared with 5.9 ± 0.8 g, P = 0.04) and total grams of sugar consumed decreased (53.8 ± 12.6 compared with 48.4 ± 7.9 g, P = 0.024), although room for further improvement exists. Although total grams of fat remained unchanged, grams of saturated fat significantly increased (7.8 ± 1.4 compared with 10.5 ± 3.4, P = 0.041). Other nutrients remained unchanged. Overall CACFP requirement and best practice compliance scores improved, although this finding was not statistically significant. No significant changes in food quality associated with substitutions occurred. Conclusions This study provides early evidence to support the beneficial impact of the revised CACFP requirements. Understanding barriers to compliance within rural NA communities would be an important next step in enhancing the health of vulnerable children.

scholarly journals Analysis of mortality from diarrheic diseases in under-five children in Brazilian cities with more than 150,000 inhabitants

2009 ◽  
Vol 25 (5) ◽  
pp. 1093-1102 ◽  
Author(s):  
Juraci Vieira Sergio ◽  
Antônio Carlos Ponce de Leon
Keyword(s):  
Mortality Rate ◽  
Time Trends ◽  
Sharp Decrease ◽  
Mortality Rates ◽  
The North ◽  
Indicator Variables ◽  
Before And After ◽  
Geographic Regions ◽  
Annual Mortality ◽  
Children Under 5

This study analyzes mortality from infectious diarrheic diseases in children under 5 years of age in Brazilian municipalities with more than 150,000 inhabitants, excluding State capitals. The annual mortality rates by municipality from 1990 to 2000 were analyzed using a multilevel model, with years as first level units nested in municipalities as second level units. The dependent variable was the yearly mortality rate by municipality, on the log scale. Polynomial time trends and indicator variables to account for differences in geographic regions were used in the modeling. Time trends were centered on 1995, so they could be modeled differently before and after 1995. From 1990 to 1995 there was a sharp decrease in mortality rates by diarrheic diseases in most Brazilian municipalities, while from 1995 to 2000 the decrease was more heterogeneous. In 1995 the North and Northeast of Brazil had higher mortality rates than the Southeast, and the differences were statistically significant. Most importantly, the study concludes that there was an important difference in the pattern of mortality rate decreases over time, comparing the country's five geographic regions.

scholarly journals ICU mortality rates in patients with sepsis before and after the Surviving Sepsis Campaign

Critical Care ◽  
2015 ◽  
Vol 19 (Suppl 1) ◽  
pp. P15 ◽  
Author(s):  
J Melville ◽  
S Ranjan ◽  
P Morgan
Keyword(s):  
Mortality Rates ◽  
Surviving Sepsis Campaign ◽  
Icu Mortality ◽  
Before And After

Mortality of First-Feeding Postlarval Walleye (Stizostedion vitreum) in Culture Ponds

1993 ◽  
Vol 50 (9) ◽  
pp. 1835-1843 ◽  
Author(s):  
Thomas A. Johnston ◽  
J. A. Mathias
Keyword(s):  
Critical Period ◽  
Mortality Rates ◽  
Predation Pressure ◽  
Stizostedion Vitreum ◽  
Exogenous Feeding ◽  
Natural Lakes ◽  
First Feeding ◽  
Zooplankton Density ◽  
Food Concentrations ◽  
Order Of Magnitude

We examined mortality rates of postlarval walleye (Stizostedion vitreum) at the onset of exogenous feeding in extensive culture ponds. Food concentrations (≥49 zooplankters∙L−1) were apparently sufficient to support successful first feeding, and no critical period of starvation mortality was evident at this stage of life. The highest observed mortality rates were associated with interspecific or intraspecific predation pressure. At low predation pressure, mean survival from stocking to the 12-mm stage was 87% in 1988 and 90% in 1989, and instantaneous mortality rates were an order of magnitude lower than those reported for postlarval walleye in natural lakes. Mortality rates calculated over the early postlarval period (stocking to 12 mm; 9–11 d) were similar to those calculated over the entire culture period (88–107 d) when predation pressure was low. At low predation pressure and 49–159 zooplankters∙L−1, there was no significant relationship between postlarval mortality rates and zooplankton density. The condition of first-feeding postlarvae captured from the pond with the lowest mean zooplankton density (49∙L−1) was significantly higher than that of postlarvae deprived of food for 48 h. Starvation is probably not a major cause of postlarval morality when zooplankton densities are ≥50∙L−1.

scholarly journals Differences in infant and child mortality before and after the Great East Japan Earthquake and Tsunami: a large population-based ecological study

BMJ Open ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. e022737 ◽  
Author(s):  
Ai Tashiro ◽  
Kayako Sakisaka ◽  
Etsuji Okamoto ◽  
Honami Yoshida
Keyword(s):  
Regression Analysis ◽  
Mortality Rate ◽  
Child Mortality ◽  
Coastal Zone ◽  
Ecological Study ◽  
Mortality Rates ◽  
Population Based ◽  
North Eastern ◽  
Infant And Child Mortality ◽  
Before And After

ObjectivesTo examine associations between access to medical care, geological data, and infant and child mortality in the area of North-Eastern Japan that was impacted by the Great East Japan Earthquake and Tsunami (GEJET) in 2011.DesignA population-based ecological study using publicly available data.SettingTwenty secondary medical areas (SMAs) in the disaster-affected zones in the north-eastern prefectures of Japan (Iwate, Fukushima and Miyagi). Participants: Children younger than 10 years who died in the 20 SMAs between 2008 and 2014 (n=1 748). Primary and secondary outcome measures: Multiple regression analysis for infant and child mortality rate. The mean values were applied for infant and child mortality rates and other factors before GEJET (2008–2010) and after GEJET (2012–2014).ResultsBetween 2008 and 2014, the most common cause of death among children younger than 10 years was accidents. The mortality rate per 100 000 persons was 39.1±41.2 before 2011, 226.7±43.4 in 2011 and 31.4±39.1 after 2011. Regression analysis revealed that the mortality rate was positively associated with low age in each period, while the coastal zone was negatively associated with fewer disaster base hospitals in 2011. By contrast, the number of obstetrics and gynaecology centres (β=−189.9, p=0.02) and public health nurses (β=−1.7, p=0.01) was negatively associated with mortality rate per person in 2011.ConclusionsIn 2011, the mortality rate among children younger than 10 years was 6.4 times higher than that before and after 2011. Residence in a coastal zone was significantly associated with higher child mortality rates.

Fish predation on neritic ctenophores from the Argentine continental shelf: A neglected food resource?

1996 ◽  
Vol 27 (1-3) ◽  
pp. 69-79 ◽  
Author(s):  
H.W. Mianzan ◽  
N. Mari ◽  
B. Prenski ◽  
F. Sanchez
Keyword(s):  
Continental Shelf ◽  
Food Resource ◽  
Fish Predation

scholarly journals Cascading effect of exotic fish fry on plankton community in a tropical Andean high mountain lake: a mesocosm experiment

2017 ◽  
Author(s):  
Yimy Herrera-Martínez ◽  
Juan César Paggi ◽  
Camilo Bernardo García
Keyword(s):  
Inorganic Nitrogen ◽  
Fish Predation ◽  
Zooplankton Biomass ◽  
Mountain Lakes ◽  
Mountain Lake ◽  
High Mountain ◽  
Exotic Fish ◽  
High Mountain Lake ◽  
Cascading Effect ◽  
Ceriodaphnia Quadrangula

<p>Fishless Andean high mountain lakes may be vulnerable to fish invasion because they tend to be small, oligotrophic and contain low zooplankton diversity. During the first decades of the twentieth century, rainbow trout, <em>Oncorhynchus mikiss</em>, was introduced in South America, and stocking of juvenile stages (fry) in lakes continues today. However, their effect on plankton in these lakes has been little studied. We performed a mesocosms experiment to assess effects of trout of different ontogenetic stages on zooplankton and phytoplankton in a tropical-Andean high mountain lake. The presence of trout fry resulted in declines in several large zooplankton taxa, increases in chlorophyll <em>a</em> and dissolved inorganic nitrogen (DIN). Our results showed that small fry consume large copepods (<em>Colombodiaptomus brandorffi</em>) at a faster rate than larger fry, and also consumed medium sized copepods (<em>Tropocyclops prasinus</em>) that are not affected by the larger trout fry. Fish of both sizes consumed <em>Ceriodaphnia quadrangula</em>, a midsize cladoceran. Fish predation had weak effect on the phytoplankton biomass, but we found a correlation between zooplankton biomass and phytoplankton richness, and significantly larger cell of the alga <em>Peridinium</em> in the presence of fish. Our results indicate that trout introduction produces cascading ecological and phenotypic effects on the plankton communities of tropical mountain lakes, similar to those observed in temperate latitudes.</p>

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