NRR

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NRR

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The following parameters were calculated using the formulas in Silveira Neto et al., (1976): net reproductive rate (Ro-ratio between the number of females in two successive generations); mean generation time (T-mean number of days from the birth of the parents to the birth of offspring); daily intrinsic rate of increase (rm); and daily finite rate of increase ([lambda]).
We constructed age-stage, two sex life table to estimate life table parameters of the beetles and population dynamics parameters (r, the intrinsic rate of increase; I>> finite rate of increase; R0 the net reproductive rate, T mean generation time) using TWOSEX-MSChart (Chi, 1988, 2012a; Chi and Liu, 1985).
Population parameters are r, the intrinsic rate of increase; [lambda], the finite rate of increase; [R.sub.0], the net reproductive rate, and T, the mean generation time.
Furthermore, the means and standard errors of the intrinsic rate of increase (r), the net reproductive rate (Ro), the mean generation time (T) and the finite rate of population increase ([lambda]), were calculated by using the Jackknife method [23, 24].
The estimated net reproductive rate ([R.sub.0]) for the white abalone population at Tanner Bank in 2002, based on the model population, was 0.28 abalone per abalone lifetime.
In addition, a fertility life table was calculated by estimating the mean generation time (T), the net reproductive rate (Ro), the intrinsic rate of increase (rm) and the finite rate of increase ([lambda]).
The net reproductive rate ([R.sub.o] = [summation]mx.lx - mx: total eggs/number of females; lx: live specimens/total specimens), the average generation length (T = [summation]mx.lx.x / [summation] mx.lx), the innate capacity for increase (rm=log Ro/ T.0.4343) and the finite increase rate ([lambda] = antilog rm) were calculated (Silveira, Nakano, Barbin, & Nova, 1976).
Parameters Results Net reproductive rate ([R.sub.o]) 223.64 [female]/[female] Mean generation period (T) 36.50 d Intrinsic rate of natural increase ([r.sub.m]) 0.145 [female]/[female]/d Doubling time ([D.sub.T]) 4.78 d
Various life table parameters including the age-stage specific survival rate ([s.sub.xj], where x = age and j = stage), the age-stage specific life expectancy ([e.sub.xj], where x = age and j = stage; it gave the expected time that an individual of age x and stage j will live), the age-stage specific fecundity ([f.sub.xj]), the mean fecundity (F), which explained the contribution of an individual of age x and stage j to the future population, the age-specific survival rate ([l.sub.x]), the age-specific fecundity ([m.sub.x]), and the population parameters (r, the intrinsic rate of increase; [lambda], the finite rate of increase, [lambda] = [e.sup.r]; [R.sub.0], the net reproductive rate; and T, the mean generation time) were calculated according to Chi method [33].
Niewiarowski and Dunham (1994) recognized that, in species with multiple clutches, the net reproductive rate of a female who did not die until all clutches had been produced would be greater than the net reproductive rate of a female with the same annual mortality but who died midyear (i.e., between clutches).
For a given kernel, the minimum speed c of a rightward moving wave of invasion will depend upon the net reproductive rate [R.sub.0] [we have taken f[prime](0) = [R.sub.0]; see Eq.
eridania were calculated: net reproductive rate ([R.sub.0]), given by the ratio between the number of females in two successive generations; mean generation time (T), the mean number of days from the birth of the parents to the birth of the offspring; daily intrinsic rate of increase ([r.sub.m]); and daily finite rate of increase ([lambda]).