POPULATION DYNAMICS OF SEPEDON FUSCIPENNIS (DIPTERA: SCIOMYZIDAE)

1972 ◽  
Vol 104 (11) ◽  
pp. 1735-1742 ◽  
Author(s):  
James W. Eckblad ◽  
Clifford O. Berg
Keyword(s):  
Population Dynamics ◽  
Population Density ◽  
Negative Binomial Distribution ◽  
Overlapping Generations ◽  
Negative Binomial ◽  
Larval Survival ◽  
Population Estimates ◽  
Net Production ◽  
Mark Release Recapture ◽  
Larval Crowding

AbstractAdults of Sepedon fuscipennis Loew were sampled periodically throughout the summers of 1969 and 1970 in a backwater habitat. Several overlapping generations of this common marsh fly were present during both summers, and its population density reached a unimodal peak both years. Population estimates based on mean number per sweep agreed well with mark–release–recapture data. These estimates showed a reasonably good fit to the negative binomial distribution and indicated that aggregation of the flies probably is due to some heterogeneity in the environment. Flies lived more than 3 months in laboratory cages, and each female laid an average of 191 eggs.Estimates were made of larval survival and net production for discrete cohorts followed in the field. The survival and production rates of larvae were greater when small snails were abundant in the habitat and much greater when the larvae were fed once before being released. Survival was not decreased perceptibly by the degree of larval crowding tested (50 larvae compared with 25 in an area of 254.34 cm2).

scholarly journals Population dynamics of Cosmoclopius nigroannulatus Stal (Hemiptera, Reduviidae) in tobacco culture

2002 ◽  
Vol 62 (4b) ◽  
pp. 819-826 ◽  
Author(s):  
S. M. JAHNKE ◽  
L. R. REDAELLI ◽  
L. M. G. DIEFENBACH
Keyword(s):  
Population Dynamics ◽  
Population Ecology ◽  
Population Estimates ◽  
Daily Survival Rate ◽  
Porto Alegre ◽  
Individual Number ◽  
Mark Release Recapture ◽  
Culture Cycle ◽  
The Individual

The role of predators influencing populations of insects considered as pests is extremely important for agroecosystems. The population ecology of Cosmoclopius nigroannulatus, a predatory reduvid associated with the tobacco culture was investigated aiming to study the population dynamics of adults, along the culture cycle. In an experimental plot of approximately 300 m², in Porto Alegre (30°0'S; 51°13'W), RS, Brazil, 270 tobacco plants were grown; each plant identified by alphanumeric coordinates. Using the mark-release-recapture method, daily samplings were done from August to December 1999, and three times a week from this date until April 2000. The adults were captured by hand, marked, sexed and released on the same plant they were captured. The individual number and plant coordinate were registered. Population estimates were analyzed by the Fisher-Ford method. In 107 sampling occasions, 604 individuals were marked, 273 males and 331 females. Three generations of C. nigroannulatus were registered during the culture cycle. The colonizing generation was represented by 14 males and 15 females (a sex ratio of 0.48), the first by 109 males and 137 females (0.44) and the second by 150 males and 179 females (0.46). The estimated daily survival rate varied between generations decreasing from 98% in the colonizing generation to 87% in the second. The observed longevity or permanence time in the experimental area varied significantly among generations, being at about 40 days in the colonizing generation, 13 days in the first and 5 days in the second. It was observed that as the population increases, the survival and/or permanence time in the area decreases, suggesting a relation between this and a decline in the available resources probably with an associated increase in intra-specific competition.

Sequential Sampling for the Imported Cabbageworm, Pieris rapae (L.)

1966 ◽  
Vol 98 (7) ◽  
pp. 741-746 ◽  
Author(s):  
D. G. Harcourt
Keyword(s):  
Negative Binomial Distribution ◽  
Binomial Distribution ◽  
Negative Binomial ◽  
Pieris Rapae ◽  
Sequential Sampling ◽  
Sampling Time ◽  
Field Conditions ◽  
Population Estimates ◽  
Population Means ◽  
Considerable Saving

AbstractSequential sampling, in which decisions depend upon the accumulated results of a series of observations, leads to considerable saving of time and money. A sequential plan, based on the negative binomial distribution and providing for population estimates in three infestation categories, was drawn up for use in control of the imported cabbageworm, Pieris rapae (L.), on cabbage. An appraisal of the plan under field conditions showed that it reduced the sampling time by 75% while rating the infestation correctly in 94 of 100 cases. With the six discrepancies, population means lay between the limits set for the infestation categories.

Population dynamics, production, and prey consumption of fathead minnows (Pimephales promelas) in prairie wetlands: a bioenergetics approach

1998 ◽  
Vol 55 (1) ◽  
pp. 15-27 ◽  
Author(s):  
W G Duffy
Keyword(s):  
Population Dynamics ◽  
Population Density ◽  
Pimephales Promelas ◽  
Standing Stock ◽  
Prey Consumption ◽  
Fathead Minnows ◽  
Prairie Wetlands ◽  
Net Production ◽  
Commercial Harvest ◽  
Two Populations

I assessed the population dynamics of fathead minnows (Pimephales promelas) in prairie wetlands and developed a bioenergetics model to estimate their production and prey consumption. I sampled populations in four wetlands weekly from late May through June and biweekly during July and August using a Kushlan 1-m2 throw trap. I imposed commercial harvest on two populations; the other two populations served as controls. Weekly population density estimates ranged from 52 000 to 356 000 ·ha-1 during early June and from 5400 to 19 700 ·ha-1 in late August. Simulated commercial harvest did not influence population density, mortality rates, or size of fathead minnows. Standing stock biomass differed among wetlands sampled, ranging from 144 to 482 kg ·ha-1 in early June and from 1 to 33 kg ·ha-1 during late August. However, differences were attributed to differential predation pressure rather than harvest pressure. Net production during the period ranged from 71.5 to 202.7 kg ·ha-1. Daily net production was greatest in early June (2.6-13.5 kg ·ha-1 ·day-1) and then declined during July and August (0.1-1.2 kg ·ha-1 ·day-1). Total mass of prey consumed by fathead minnows ranged from 332.7-1104.8 kg ·ha-1 among wetlands.

REQUIRED SAMPLE SIZE FOR EARLY INSTAR LARVAE OF SPRUCE BUDWORM,CHORISTONEURA FUMIFERANA(LEPIDOPTERA: TORTRICIDAE), IN NEWFOUNDLAND

1983 ◽  
Vol 115 (11) ◽  
pp. 1523-1527 ◽  
Author(s):  
E. J. Dobesberger ◽  
K. P. Lim
Keyword(s):  
Population Density ◽  
Sample Size ◽  
Negative Binomial Distribution ◽  
Binomial Distribution ◽  
Negative Binomial ◽  
Choristoneura Fumiferana ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Early Instar

AbstractRequired sample size was determined for early instar (2nd to 4th instar) larvae of spruce budworm,Choristoneura fumiferana(Clem.). Larval counts on mid-crown 45 cm branch tips and whole branches of balsam fir,Abies balsamea(L.) Mill., were described in terms of the negative binomial distribution. The values of commonkfor the branch tip and whole branch sample units were 1.550 and 1.636, respectively. The required sample size at densities greater than or equal to one appears feasible. It is recommended that the 45 cm branch tip be used to estimate population density of early instar larvae in Newfoundland.

Niche Sharing in Intertidal Mollusks and Decapods in Rocky Shore of Easter Island

2019 ◽  
Vol 53 (5) ◽  
pp. 417-422
Author(s):  
P. De los Ríos ◽  
E. Ibáñez Arancibia
Keyword(s):  
Spatial Distribution ◽  
Negative Binomial Distribution ◽  
Binomial Distribution ◽  
Rocky Shore ◽  
Negative Binomial ◽  
Null Model ◽  
Easter Island ◽  
Published Data ◽  
Distribution Analysis ◽  
Field Works

Abstract The coastal marine ecosystems in Easter Island have been poorly studied, and the main studies were isolated species records based on scientific expeditions. The aim of the present study is to apply a spatial distribution analysis and niche sharing null model in published data on intertidal marine gastropods and decapods in rocky shore in Easter Island based in field works in 2010, and published information from CIMAR cruiser in 2004. The field data revealed the presence of decapods Planes minutus (Linnaeus, 1758) and Leptograpsus variegatus (Fabricius, 1793), whereas it was observed the gastropods Nodilittorina pyramidalis pascua Rosewater, 1970 and Nerita morio (G. B. Sowerby I., 1833). The available information revealed the presence of more species in data collected in 2004 in comparison to data collected in 2010, with one species markedly dominant in comparison to the other species. The spatial distribution of species reported in field works revealed that P. minutus and N. morio have aggregated pattern and negative binomial distribution, L. variegatus had uniform pattern with binomial distribution, and finally N. pyramidalis pascua, in spite of aggregated distribution pattern, had not negative binomial distribution. Finally, the results of null model revealed that the species reported did not share ecological niche due to competition absence. The results would agree with other similar information about littoral and sub-littoral fauna for Easter Island.

ANALISIS RISIKO OPERASIONAL MENGGUNAKAN PENDEKATAN DISTRIBUSI KERUGIAN DENGAN METODE AGREGAT

2011 ◽  
Vol 10 (2) ◽  
pp. 1
Author(s):  
Y. ARBI ◽  
R. BUDIARTI ◽  
I G. P. PURNABA
Keyword(s):  
Negative Binomial Distribution ◽  
Binomial Distribution ◽  
Negative Binomial ◽  
Financial Institution ◽  
Expected Value ◽  
Insurance Companies ◽  
Limited Data ◽  
Loss Distribution Approach ◽  
Potential Loss ◽  
The Impact

Operational risk is defined as the risk of loss resulting from inadequate or failed internal processes or external problems. Insurance companies as financial institution that also faced at risk. Recording of operating losses in insurance companies, were not properly conducted so that the impact on the limited data for operational losses. In this work, the data of operational loss observed from the payment of the claim. In general, the number of insurance claims can be modelled using the Poisson distribution, where the expected value of the claims is similar with variance, while the negative binomial distribution, the expected value was bound to be less than the variance.Analysis tools are used in the measurement of the potential loss is the loss distribution approach with the aggregate method. In the aggregate method, loss data grouped in a frequency distribution and severity distribution. After doing 10.000 times simulation are resulted total loss of claim value, which is total from individual claim every simulation. Then from the result was set the value of potential loss (OpVar) at a certain level confidence.

scholarly journals On the Accuracy of the Generalized Gamma Approximation to Generalized Negative Binomial Random Sums

Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1571
Author(s):  
Irina Shevtsova ◽  
Mikhail Tselishchev
Keyword(s):  
Negative Binomial Distribution ◽  
Binomial Distribution ◽  
Law Of Large Numbers ◽  
Negative Binomial ◽  
Infinite Divisibility ◽  
Random Sums ◽  
Generalized Gamma ◽  
Second Moments ◽  
Large Numbers ◽  
Generalized Negative Binomial Distribution

We investigate the proximity in terms of zeta-structured metrics of generalized negative binomial random sums to generalized gamma distribution with the corresponding parameters, extending thus the zeta-structured estimates of the rate of convergence in the Rényi theorem. In particular, we derive upper bounds for the Kantorovich and the Kolmogorov metrics in the law of large numbers for negative binomial random sums of i.i.d. random variables with nonzero first moments and finite second moments. Our method is based on the representation of the generalized negative binomial distribution with the shape and exponent power parameters no greater than one as a mixed geometric law and the infinite divisibility of the negative binomial distribution.

Sign in / Sign up

Export Citation Format

Share Document