A Population Model of Astrocaryum Mexicanum and a Sensitivity Analysis of its Finite Rate of Increase

1984 ◽  
Vol 72 (3) ◽  
pp. 977 ◽  
Author(s):  
D. Pinero ◽  
M. Martinez-Ramos ◽  
J. Sarukhan
Keyword(s):  
Sensitivity Analysis ◽  
Population Model ◽  
Finite Rate ◽  
Rate Of Increase

Biotic interactions and the population dynamics of the long-lived columnar cactus Neobuxbaumia tetetzo in the Tehuacán Valley, Mexico

1999 ◽  
Vol 77 (2) ◽  
pp. 203-208 ◽  
Author(s):  
Héctor Godínez-Alvarez ◽  
Alfonso Valiente-Banuet ◽  
Leopoldo Valiente Banuet
Keyword(s):  
Population Dynamics ◽  
Matrix Models ◽  
Biotic Interactions ◽  
Positive Interactions ◽  
Elasticity Analysis ◽  
Finite Rate ◽  
Tehuacán Valley ◽  
Columnar Cactus ◽  
Tehuacan Valley ◽  
Rate Of Increase

The giant columnar cactus Neobuxbaumia tetetzo (Coulter) Backeberg is the dominant species of a vegetation type locally called "tetechera" that occupies ca. 400 km2 in the Tehuacán Valley. As a way to analyse the role of biotic interactions on the population dynamics of this species, we conducted an elasticity analysis, using matrix models elaborated from field data, to determine the finite rate of increase and the critical stages of the life cycle that were related to the biotic interactions occurring during these stages. Although the estimated finite rate of increase did not differ from unity there were significant differences between the actual and predicted size distributions. Elasticity analysis showed that survivorship was the most important life-history parameter to the finite rate of increase. Because survivorship depends on the presence of nurse plants, our results emphasise the importance of positive interactions on the population dynamics of long-lived columnar cacti.Key words: biotic interactions, Cactaceae, deserts, matrix models, population dynamics.

BIONOMICS OF BLATTISOCIUS KEEGANI (FOX) (ACARINA: ASCIDAE), A PREDATOR ON EGGS OF PESTS OF STORED GRAINS

1967 ◽  
Vol 45 (6) ◽  
pp. 1093-1099 ◽  
Author(s):  
Philip S. Barker
Keyword(s):  
Life History ◽  
Life Cycle ◽  
Female Offspring ◽  
Finite Rate ◽  
Rate Of Increase ◽  
Stored Grains ◽  
History Of ◽  
Cryptolestes Turcicus

The life history of Blattisocius keegani (Fox) was studied at 60, 72, and 80 °F, and at relative humidities (r.h.) of 70 to 75% and 95 to 100%. A life cycle of 6 to 7 days was found at 80 °F. Oviposition was studied at 80 °F and 70 to 75% r.h.; the finite rate of increase (λ) was 3.33 female offspring per female per week. Approximately three Cryptolestes turcicus (Grouvelle) eggs were required to rear one B. keegani to adulthood at 80 °F and 70 to 75% r.h. Female B. keegani that consumed one C. turcicus egg per day were able to oviposit. The hosts investigated included eggs of six species of beetles, and two species of mites that infest stored grains.

The response of a predator, Hypoaspis aculeifer (Canestrini) (Acarina:Laelapidae), to two species of prey

1969 ◽  
Vol 47 (3) ◽  
pp. 343-345 ◽  
Author(s):  
Philip S. Barker
Keyword(s):  
Prey Species ◽  
Tyrophagus Putrescentiae ◽  
Finite Rate ◽  
Hypoaspis Aculeifer ◽  
Rate Of Increase

The effect of two prey species, Tyrophagus putrescentiae (Schrank) and Glycyphagus domesticus (de Geer), on the oviposition of the predator Hypoaspis aculeifer (Canestrini) was studied. The H. aculeifer females fed on T. putrescentiae laid more eggs and lived longer than those fed on G. domesticus. Predators fed on G. domesticus laid more eggs per day and had a shorter mean generation than predators fed on T. putrescentiae. The greatest finite rate of increase of H. aculeifer was obtained when G. domesticus was the prey.

Evaluation of an experimental wolf reduction and its impact on deer in Papineau-Labelle Reserve, Quebec

1992 ◽  
Vol 70 (8) ◽  
pp. 1595-1603 ◽  
Author(s):  
François Potvin ◽  
Hélène Jolicoeur ◽  
Laurier Breton ◽  
Rolland Lemieux
Keyword(s):  
Reduction Rate ◽  
Management Tool ◽  
Finite Rate ◽  
Rate Of Increase ◽  
Wintering Area ◽  
Current Context ◽  
The Mean ◽  
Four Blocks

From 1984 to 1986, 56 wolves were removed by aerial shooting from two reduction blocks in Papineau-Labelle Reserve: the mean reduction rate was 71% in RB1 and 40% in RB2, compared with 17 and 9% for two untreated blocks (UB1 and UB2). Corresponding mean wolf densities in the four blocks at the end of winter were 0.6, 1.2, 1.6, and 1.7 wolves/100 km2, respectively. Each year, wolf numbers returned to their former level in the subsequent winter in RB1, mainly through immigration. Three blocks were each associated with a large deer wintering area containing 1400–1700 animals before the wolf reduction. The deer yard in RB1 reached a population of 4200 deer, a 1.32% finite rate of increase per year, compared with annual rates of 1.15–1.18% in UB1 and RB2. The harvest of bucks was not affected by the wolf reduction. The number of fawns per 100 does in the harvest was higher in RB1 than in UB1 in 1985 and 1986. We do not recommend wolf reduction as a management tool in the current context, as deer numbers increased markedly, even where no control was applied, as a consequence of mild winters.

Development, survival and reproduction of a potential biological control agent, Lasioseius japonicus Ehara (Acari: Blattisociidae), on eggs of Drosophila melanogaster (Diptera: Drosophilidae) and Sitotroga cerealella (Lepidoptera: Gelechiidae)

2020 ◽  
Vol 25 (8) ◽  
pp. 1461-1471
Author(s):  
Lixia Xie ◽  
Na Zhang ◽  
Xinran Wu ◽  
Kai Liu ◽  
Chenlin Liu ◽  
...  
Keyword(s):  
Generation Time ◽  
Intrinsic Rate ◽  
Reproductive Rate ◽  
Intrinsic Rate Of Increase ◽  
Sitotroga Cerealella ◽  
Finite Rate ◽  
Net Reproductive Rate ◽  
Rate Of Increase ◽  
Survival And Reproduction ◽  
The Mean

Lasioseius japonicus is a species of soil-dwelling predatory mite with great potential for controlling insect pests and has a broad application prospect in biological control. This study was conducted under indoor conditions to explore the development, survival and reproduction of L. japonicus on two diets. Through the construction of two-sex life table of L. japonicus, it was revealed that, when it preyed on eggs of Drosophila melanogaster, the intrinsic rate of increase (r) was 0.2614 d-1, the net reproductive rate (R0) was 57.76 offspring, the finite rate of increase (λ) was 1.2988 d-1, and the mean generation time (T) was 15.49 d. When preying on eggs of Sitotroga cerealella, the intrinsic rate of increase (r) of L. japonicus was 0.1560 d-1, the net reproductive rate (R0) was 20.96 offspring, the finite rate of increase (λ) was 1.1690d-1, and the mean generation time (T) was 19.41 d. In addition, the life expectancy and population growth trend of L. japonicus were simulated based on the above two alternative prey species. The results showed that feeding on the eggs of D. melanogaster is more beneficial to the growth and reproduction of L. japonicus.

scholarly journals Biotic potential and reproductive parameters of Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) in the laboratory

2019 ◽  
Vol 79 (3) ◽  
pp. 488-494 ◽  
Author(s):  
A. Specht ◽  
V. F. Roque-Specht
Keyword(s):  
Intrinsic Rate ◽  
Reproductive Rate ◽  
Intrinsic Rate Of Increase ◽  
Reproductive Parameters ◽  
Finite Rate ◽  
Net Reproductive Rate ◽  
Biotic Potential ◽  
Rate Of Increase ◽  
The Mean ◽  
Lepidoptera Noctuidae

Abstract In this study we evaluate the biotic potential and reproductive parameters of Spodoptera cosmioides (Walker, 1858) under controlled conditions (25 ± 1 °C, 70 ± 10% RH and 14 hour photophase). Females, on average, (14.433 days) did not live significantly longer than their male counterparts (13.100 days). The mean durations of the pre-oviposition, oviposition and post-oviposition periods were 2.767, 10.600 and 1.067 days, respectively. The mean fecundity of females was 5,073.533 eggs and the mean fertility was 5,021.027 larvae. On average, females copulated 1.167 times. Fecundity was positively correlated with the number of copulations (r = 0.583, P <0.001). The number of copulations, however, was negatively correlated whit the duration of the pre-oviposition (r = -0.560, P = 0.007) and oviposition (r = -0.479, P = 0.048) periods, and overall longevity (r = -0.512, P = 0.031). The biotic potential was estimated at 6.547 x 1021 individuals/female/year. The net reproductive rate (Ro) was 2,193.722 times per generation and the mean generation time (T) was 46.407 days. The intrinsic rate of increase (rm) was 0.166, with a finite rate of increase (λ) of 1.180, per week.

Abundance, Distribution, and Rate of Increase of Feral Goats in Western Australia.

1993 ◽  
Vol 15 (2) ◽  
pp. 334 ◽  
Author(s):  
CJ Southwell ◽  
GS Pickles
Keyword(s):  
Western Australia ◽  
Standard Error ◽  
South Australia ◽  
Aerial Survey ◽  
Mortality Data ◽  
Abundance Distribution ◽  
Finite Rate ◽  
Rate Of Increase ◽  
Feral Goat

Aerial survey of 1.2 million km2 of Western Australia in 1987 and 1990 indicated minimum feral goat populations (� standard error) of 363,000�44,000 and 596,500�41,200 respectively. The observed rate of increase over the three-year period was r = 0.17, corresponding to a finite rate of increase of 18% per annum. In the period between the surveys an average of 187,000 goats were known to be commercially harvested each year. The observed rate of increase is below maximum potential rates of increase predicted theoretically for goat-sized mammals and derived from age-specific fecundity and mortality data for feral goats in South Australia.

Population growth performance of Panonychus ulmi Koch (Acarina: Tetranychidae) on different fruit trees

2021 ◽  
Author(s):  
Ismail Kasap ◽  
Remzi Atlihan
Keyword(s):  
Population Growth ◽  
Host Plants ◽  
Prunus Avium ◽  
Panonychus Ulmi ◽  
Intrinsic Rate Of Increase ◽  
Pest Species ◽  
Finite Rate ◽  
Net Reproductive Rate ◽  
European Red Mite ◽  
Rate Of Increase

The European red mite, Panonychus ulmi (Acari: Tetranychidae) is an important pest species on deciduous plants in Turkey, especially on apple. In this study, development, survival, and reproduction of European red mite, P. ulmi were studied on different host plants under laboratory conditions (25±2 °C,% 60±10 RH and16:8 L:D photoperiod). Population performance of P. ulmi was obtained on its different host plants including apple (Malus communis L.), quince (Cydonia oblonga Mill.), cherry (Prunus avium L.), and sour cherry (Prunus cerasus L). The life history raw data of P. ulmi were analyzed by using the age-stage, two-sex life table. Results indicated that the highest net reproductive rate, intrinsic rate of increase, and finite rate of increase as well as the longest mean generation time, were obtained on apple cv. Starking delicious. The population projection simulated by using life tables based on the 0.025th and 0.975th bootstrap results of the finite rate of increase displayed the same trend with population growth parameters. Results suggested that apple cv. Starking Delicious was the favorable host for P. ulmi, however, there is potential for the pest to become a serious pest on other host plants tested under favorable conditions.

Population dynamics of northern white-tailed deer during mild winters: evidence of regulation by food competition

2000 ◽  
Vol 78 (5) ◽  
pp. 764-776 ◽  
Author(s):  
André Dumont ◽  
Michel Crête ◽  
Jean-Pierre Ouellet ◽  
Jean Huot ◽  
Jean Lamoureux
Keyword(s):  
Population Dynamics ◽  
Survival Rates ◽  
Food Competition ◽  
Finite Rate ◽  
Mortality Pattern ◽  
Rate Of Increase ◽  
Wintering Area ◽  
Probability Of Death ◽  
Low Levels ◽  
Two Populations

We studied white-tailed deer (Odocoileus virginianus borealis) at the northeastern limit of their range after their density had decreased as a result of harsh winters aggravated by coyote predation. We compared two populations wintering in adjacent areas. In the Lac Témiscouata wintering area (LTWA), deer and browse density averaged 10 animals/km2 and 127 000 deciduous twigs/ha compared with 20 deer/km2 and 68 000 twigs/ha, respectively, at the Pohénégamook wintering area (PWA). For 75 radio-collared deer, the probability of death was highest during the short spring migration and remained elevated in winter, whereas fewer deaths occurred in summer and none during autumn migration. PWA deer had a higher mortality rate than did LTWA animals and died mostly in winter, from predation, starvation, and collision equally. Based on observed survival rates, we estimated that the finite rate of increase averaged [Formula: see text]1.25 and [Formula: see text]1.00 for LTWA and PWA populations, respectively. At PWA, we examined 129 carcasses to determine the mortality pattern of deer. Among adults, we did not detect significant differences related to sex. Starvation and predation affected more fawns and old deer than prime animals, whereas collision appeared to be nonselective. Most cases of starvation occurred after the beginning of March, when body reserves dropped to low levels. We conclude that competition for winter forage regulated PWA deer during the study.

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